To the best of our knowledge, it is still unknown how perceived limb heaviness affects rehabilitation adherence. As rehabilitation adherence is very important for the functional recovery of patients with stroke, it is important to explore the relationship between perceived limb heaviness and rehabilitation adherence.We retrospectively reviewed the data of patients with consecutive stroke recruited in the CIRCLE study. The influence of age, gender, time from onset to enrollment, educational background, hypertension, diabetes, Modified Rankin Scale (MRS), and National Institutes of Health Stroke Scale (NIHSS) on rehabilitation adherence was analyzed. Multiple linear regression analysis was used to examine the association between perceived limb heaviness and rehabilitation adherence changes.B = −9.681 ± 1.494, p < 0.05) and R2 was 0.332 and 0.074 if the muscle strength of the upper limb and perceived limb heaviness were included in the model and the model was without perceived limb heaviness, respectively.A total of 108 participants completed the study. About 40 (37.0%) participants felt limb heaviness. The mean scores on the Medical Research Council (MRC) scale for the upper affected limb strength were 3.05 ± 1.7, and the mean score on the exercise adherence questionnaire (EAQ) was 34.27 ± 8.9. Univariate analysis showed that rehabilitation adherence levels differed in upper limb muscle strength and whether they perceived limb heaviness. After adjustment for independent predictors, we found that perceived limb heaviness was associated with rehabilitation adherence (By identifying patients with stroke with limb heaviness, it led to lower levels of motor functional rehabilitation adherence. We must pay more attention to limb heaviness and provide effective interventions to improve rehabilitation adherence and promote patient recovery. Stroke is the leading cause of mortality and disability worldwide, with low- and middle-income countries (LMICs) accounting for 89% of all stroke-related disability-adjusted life-years . Many guAdherence is defined as “the behavior of a patient in accordance with medical instructions” . AdherenHowever, rehabilitation was often hampered by low adherence rates . As a reAdherence to rehabilitation in stroke is influenced not only by disease-specific factors, such as spasticity, fatigue, and paresis, but also by psychosocial factors –15. PercLimb heaviness is also one of the perceptual phenomena, where patients with stroke experience the affected limb as feeling heavier . ResearcIn this study, we retrospectively reviewed data from patients with consecutive stroke recruited into the CIRCLE study  Clinica. InclusiAll subjects had provided written informed consent before participating in the study, and the protocols had been approved by the human ethics committee of The Second Affiliated Hospital of Zhejiang University. All clinical investigations were conducted in accordance with the principles outlined in the Declaration of Helsinki.All participants received the questionnaire on perceived limb heaviness and functional rehabilitation adherence. Demographic data  were collected from medical records. We also collected the Modified Rankin Scale (MRS) and the NIHSS.Muscle strength of the affected limbs was assessed by the Medical Research Council (MRC) Scale. Biceps brachii and triceps brachii were accessed to represent the upper limb muscle and quadriceps femoris was assessed to represent the lower limb muscle. All patients with stroke had three attempts, and the best result was considered the outcome.Perceived limb heaviness has two questions, asking participants to agree or disagree with the statement, “My limbs can become very heavy.” “My limbs can become very heavier than the other side” . ParticiThe EAQ was developed based on the exercise guidelines for patients with stroke in the USA, which is based on a large number of references , with a Data analysis was conducted using SPSS 24.0. All statistical tests were two-tailed, and an alpha of 0.05 was taken to indicate significance. Descriptive statistics were used to report the demographic and clinical characteristics of patients with stroke, including age, gender, time from onset to enrollment, educational background, hypertension, diabetes, limb muscle strength, NHISS, MRS, perceived limb heaviness, and EAQ scores. Categorical data, such as gender, educational background, hypertension, diabetes, and perceived limb heaviness, were examined by individual Chi-squared tests, and group differences between continuous variables, such as age, time from onset to enrollment, muscular strength of the limbs, NHISS, and MRS, were examined by analysis of variance (ANOVA) and nonparametric tests.p > 0.10 for exclusion).Limb muscle strength, perceived limb heaviness, and EAQ scores were examined using multiple linear regression analysis, which was used to examine the association between perceived limb heaviness and rehabilitation adherence changes with backward stepwise selection  that could affect rehabilitation were excluded. Three patients with stroke were discharged within a week. Two patients with stroke were declined to participate. In addition, one patient was excluded because the patient was transferred to the intensive care unit. As a result, 108 subjects with stroke were enrolled in the present study .Approximately 73.1% of the participants were men, with a mean age of 62.10 ± 13.3 years. The mean time from onset to enrollment was 5.22 ± 2.4 days. The mean score of the MRC scale was 3.05 ± 1.7 and 3.64 ± 1.4 for the upper limbs and the lower limbs, respectively. The mean NHISS was 6.59 ± 3.5. The mean MRS was 3.85 ± 0.4. Comorbidities were hypertension (67.6%) and diabetes (25.9%).The mean EAQ score was 34.27 ± 8.9. About 40 (37.0%) patients with stroke felt limb heaviness. Demographic characteristics of the 108 patients with stroke are summarized in R2 was 0.332 and 0.074 in case of the model with upper limb muscle strength and perceived limb heaviness and the model without perceived limb heaviness, respectively  perceived limb heaviness, as an explanatory variable, is independently associated with a greater change in rehabilitation adherence; (2) limb muscle strength may not affect rehabilitation adherence, which means that the rehabilitation adherence level did not vary with muscle strength; and (3) demographic data and functional status may not affect the rehabilitation adherence level.The results of this study showed us an interesting conclusion that the perception of limb heaviness as a common symptom after stroke is strongly related to rehabilitation adherence . Limb heThe research also found that the rehabilitation adherence level may not have a relationship with limb muscle strength. These results differed from previous studies in which muscle problems were a factor , 17. Thep = 0.405; p = 0.626) and probably because most of the participants were men (73.1%), the imbalance in the men–women ratio may not result in differences in rehabilitation adherence levels. Rehabilitation adherence levels were not different in MRS (p = 0.850). Low levels of rehabilitation adherence would worsen their ability in ADL performance. However, ADL before rehabilitation may have little effect on adherence. About 78.7% of patients with stroke in our study had moderate and high adherence after week 1 (p = 0.251). A reasonable explanation was that the effects of a neurological deficit on rehabilitation adherence were less apparent in the acute stage.In addition, the difference in the level of rehabilitation adherence did not differ among ages  and the medical and health science and technology planning project of the Zhejiang province (2019320070).The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Advances in Rehabilitation Science and Practice.We at SAGE are excited to announce to our readers and authors several ambitious changesto Rehabilitation Process and Outcome. The title of the journal will be changing toThe journal aims to capture cutting-edge research and developments in the clinicalpractice of rehabilitation in medical conditions affecting adults and children. We willpublish innovations from the field of neurorehabilitation, musculoskeletal conditions,sports sciences, trauma, chronic pain, cardiopulmonary rehabilitation, stroke,rehabilitation technology, outcome measurement and other areas related torehabilitation.Apart from researchers in the field of rehabilitation, this journal is also aimed at awide variety of clinical specialists in the field – physicians specialising in Physicaland Rehabilitation Medicine ,physiotherapists, occupational therapists, nurses, psychologists, speech and languagetherapists, dieticians, support workers and other allied healthcare professionalsworking in the area of rehabilitation for chronic conditions. The journal is also likelyto attract articles from related fields like Neurosciences, Orthopaedics and Trauma,Palliative care, Geriatrics, Cardiology and Respiratory Medicine.Advances in Rehabilitation Science and Practice will continue to retainits focus on processes and outcomes in rehabilitation but wishes to expand its remit tobasic sciences, clinical trials, qualitative research, clinical interventions, patientand public involvement, as well as health services and policy research. Apart from ourcontinued emphasis on original research, systematic review and clinical trials, thejournal aims to have the following special featuresLong COVID: Mechanisms, Treatments and Outcomes iscurrently open for submissions)Special Issues focusing on a particular area of interest  by the author,institution or research funder of the accepted manuscript.Advances in Rehabilitation Science and Practice publisharticles with a direct impact on improving care for patients with chronic conditions andand make a difference to their function and quality of life.We are delighted to welcome the newest members of the Senior Editorial Team, who havejoined us to manage the expanded scope of the journal, facilitate a robust peer-reviewprocess, manage special issue editions and shape our strategic vision. They come fromvarious rehabilitation disciplines and have an impressive track record in basic scienceresearch and clinical practice. Some of them have championed translational research andare keen to see Advances in Rehabilitation Science andPractice become the go-to journal in the fascinating area of rehabilitationresearch and clinical practice. We welcome your suggestions to make the journal highlyimpactful and improve the lives of individuals with rehabilitation needs, to whom thisjournal is dedicated.We acknowledge the presence of other journals in this space doing the same but trulybelieve we have the ambition and the right team to build our reputation from here andbecome one of the most reputable journals in the field. This is an exciting phase of ourgrowth and our vision to see


The androgen receptor (AR) signaling pathway is critical for growth and differentiation of prostate cancer cells. For that reason, androgen deprivation therapy with medical or surgical castration is the principal treatment for metastatic prostate cancer. More recently, new potent AR signaling inhibitors (ARSIs) have been developed. These drugs improve survival for men with metastatic castration-resistant prostate cancer (CRPC), the lethal form of the disease. However, ARSI resistance is nearly universal. One recently appreciated resistance mechanism is lineage plasticity or switch from an AR-driven, luminal differentiation program to an alternate differentiation program. Importantly, lineage plasticity appears to be increasing in incidence in the era of new ARSIs, strongly implicating AR suppression in this process. Lineage plasticity and shift from AR-driven tumors occur on a continuum, ranging from AR-expressing tumors with low AR activity to AR-null tumors that have activation of alternate differentiation programs versus the canonical luminal program found in AR-driven tumors. In many cases, AR loss coincides with the activation of a neuronal program, most commonly exemplified as therapy-induced neuroendocrine prostate cancer (t-NEPC). While genetic events clearly contribute to prostate cancer lineage plasticity, it is also clear that epigenetic events—including chromatin modifications and DNA methylation—play a major role. Many epigenetic factors are now targetable with drugs, establishing the importance of clarifying critical epigenetic factors that promote lineage plasticity. Furthermore, epigenetic marks are readily measurable, demonstrating the importance of clarifying which measurements will help to identify tumors that have undergone or are at risk of undergoing lineage plasticity. In this review, we discuss the role of AR pathway loss and activation of a neuronal differentiation program as key contributors to t-NEPC lineage plasticity. We also discuss new epigenetic therapeutic strategies to reverse lineage plasticity, including those that have recently entered clinical trials. Prostate cancer is the second leading cause of cancer-related death in men in the United States with an estimated 34,500 deaths predicted for 2022 . Since tHowever, even though ARSIs prolong survival, resistance is nearly universal, and there are limited treatment options once tumors become resistant. Resistance to ARSI treatment may be broken down into two major categories: AR signaling-dependent and AR signaling-independent . MaintenAn AR signaling-independent state is defined by reduced reliance on the AR and activation of other factors, such as MYCN and AURKA that promote cell survival . One sucA key challenge in developing effective treatments for patients with advanced prostate cancer is inter- and even intra-patient tumor heterogeneity –25. Therde novo NEPC comprises less than 1% of newly diagnosed prostate tumors, therapy-induced (t)-NEPC emerging after ARSI treatment represents approximately 20% of CRPC tumors in recent biopsy studies ; PTEN and RB1 loss (DKO); or PTEN, RB1, and TP53 loss (TKO)  . Comparess (TKO) . DKO andss (TKO) . The aututations . This su, et al. , Ku, et , et al. .RB1 and TP53 loss was provided by Park, et al., who sought to identify factors that cooperate to promote NEPC , RB1-short hairpin RNA, overexpression of c-Myc, and overexpression of BCL2  is known to demethylate lysine 4 on histone H3 and lysine residues on several non-histone proteins, including TP53, E2F1, DNMT1, and HIF-1α . LSD1 mall lines . CollectLSD1 called LSD1+8a that was specifically expressed in NEPC vs. adenocarcinoma in PDX models and metastatic biopsies  expression in both amphicrine and NEPC tumors (The restrictive element-1 silencing transcription factor (REST) is a repressor of neuronal differentiation . REST haC tumors . BAF53B C tumors . The excC tumors –113. CytC tumors . InteresC tumors . FinallyC tumors . We founC tumors . FurtherC tumors . Collectde novo NEPC from adenocarcinoma , and blood markers  as enrollment criteria. Several other therapeutic trials have focused on specific clinical markers to enrich for patients with “aggressive variant prostate cancer” (AVPC), though this clinical classification likely includes a mixture of tumor subtypes that may or may not be AR-driven.PTEN, RB1, and TP53. Given the key role these genes play in both suppressing lineage plasticity and proliferation  enrolling AVPC used mutations or loss of function events in the tumor suppressors feration , 61, enrferation –63, 117.via non-invasive methods. Molecular imaging may be one promising avenue. Radionuclide scans using tracers conjugated to prostate specific membrane antigen (PSMA) and dihydrotestosterone (DHT) have been widely studied in prostate cancer (89Zr)-labeled DLL3 targeting antibody that specifically detected neuroendocrine PDXs in vivo  via morphology and immunofluorescence staining  . MYCN isAnother targeted agent, rovalpituzumab tesirine (an antibody drug conjugate against DLL3), was tested in a phase I/II trial (NCT02709889) that included 18 patients with NEPC and found an objective response rate of 10% . There aMultiple phase I-II studies have tested epigenetic targeted agents in CRPC. The majority of completed and ongoing trials of epigenetic targeted agents recruited from the general CRPC population and were not specifically focused on NEPC, thus making it difficult to determine the effectiveness of these agents in this molecular subset.As stated previously, there are marked DNA methylation differences between adenocarcinoma and NEPC tumors, and DNMTs have been implicated as key lineage plasticity factors . While DHDAC regulate AR activity  and haveAs previously discussed, BET bromodomain proteins are chromatin readers that cooperate with several transcription factors, including the AR and E2F1 , 143. SeOther epigenetic targets are also being assessed in ongoing trials. The histone demethylase LSD1 is being studied in a phase I/II study that includes neuroendocrine tumors (NCT02712905). Inhibitors of EZH2 are also being tested in ongoing trials alone or in combination with ARSIs (NCT04986423). Notably, a phase I trial of DS3201 (EZH1/2 inhibitor) and ipilimumab is specifically recruiting AVPC in addition to other genitourinary cancers (NCT04388852).The current focus of t-NEPC research is how to identify these tumors more accurately and treat them more effectively once they develop after ARSI treatment. However, identification of tumors at greatest risk of ARSI-induced AR pathway loss and t-NEPC lineage plasticity before these changes occur may lead to better outcomes. Indeed, recent reports indicate that significant heterogeneity exists in tumors that have undergone lineage plasticity , which mPTEN, RB1, and TP53). Single cell assays such as ATAC sequencing paired with RNA sequencing may provide information about the baseline gene expression program of distinct cell populations and their capacity to turn on other gene expression programs, including those linked with NEPC lineage plasticity. Spatial profiling may help to unravel immune and microenvironmental contributions to lineage plasticity and will be crucial for understanding the communication and cooperativity of different cell populations present in a tumor. Inclusion of non-invasive assays using CTCs or cfDNA may help facilitate serial collection of samples that may give clues about risk of NEPC lineage plasticity that do not require invasive, repeated sampling of patients.Understanding lineage plasticity risk requires a longitudinal assessment of patients with matched assays (before treatment and at the time of progression). We do not yet know the best measures of risk of NEPC lineage plasticity, and there are no markers that exist to risk-stratify patients. Therefore, we believe it will be important to measure several factors that may contribute to NEPC lineage plasticity risk: genomic, epigenomic, and microenvironmental features. Whole genome or whole exome DNA sequencing can identify genomic loss of known tumor suppressor genes  that incorporates many of the aforementioned assays in an effort to improve our ability to identify those at greatest risk of developing t-NEPC after ARSI treatment. Once studies establishing markers of lineage plasticity risk are completed, prospective validation will be necessary. It is our hope that improvements in non-invasive detection through blood-based assays or molecular imaging will hasten completion of such studies and improve our ability to identify those at greatest risk of developing t-NEPC. The next critical step will be to develop clinical trials testing drugs that suppress induction of an NEPC program or that maintain AR expression and signaling. We believe that epigenetic therapies may be a particularly promising approach for these patients.Both genetic and epigenetic changes play a key role in therapy-induced AR pathway loss and t-NEPC lineage plasticity. Understanding mechanisms by which t-NEPC lineage plasticity occurs and markers that indicate this transition has taken place are critical for making progress for this group of patients. We predict that combination clinical trials with ARSIs + lineage plasticity-modifying epigenetic therapies alone or with other targeted agents will be critical for making progress. Advances in detection of lineage plasticity risk will be important to prevent this newly appreciated, aggressive form of ARSI resistance from happening in the first place.WKS, AMM, TCW, and JJA conceived the article. WKS, AMM, TCW, CM, and JJA reviewed the literature and wrote the first draft of the manuscript. WKS made the figure. TCW made the table. WKS, ZD, CM, JAY, and JJA edited the manuscript.This work was supported by National Cancer Institute (NCI) R01 (CA251245); The Pacific Northwest Prostate Cancer Specialized Programs of Research Excellence (SPORE) NCI P50 CA097186; the Michigan Prostate SPORE NCI P50 CA186786; the NCI Drug Resistance and Sensitivity Network NCI P50 CA186786-07S1; NCI Training Grant T32 CA009676; NCI Training Grant 5-T32 CA180984-07; NCI Training Grant T32 CA009357; Department of Defense Idea Award (W81XWH-20-1-0405); National Comprehensive Cancer Network (NCCN)/Astellas Pharma Global Development Award; a Prostate Cancer Foundation Challenge Award; and a Sheppard Family Foundation Sheppard Scholar Award.JJA reports consulting and speaker’s fees from Astellas Pharma, consulting fees from Dendreon, consulting fees from Merck, consulting fees from Bristol Myers Squibb, and research support to his institution from Astellas Pharma, Zenith Epigenetics, and Beactica.The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Medical rehabilitation is a valuable component to restore physical and mental health, to prevent social isolation and to ensure a return to work. Due to the demographic change and the still increasing number of Post-Covid-19 patients, the demand for rehabilitation is still increasing. Latest, the COVID-19 pandemic elucidated that especially people from lower socio-economic backgrounds are disproportionally affected by health crisis. The aim of this study was to determine the influence of socio-demographic and socio-economic factors on quantitative exercise therapy in medical rehabilitation and to clarify the divergence of existing research findings. In our study we used data from 824.606 rehabilitation cases  and investigated the role of age and gender, marital status, social status and location towards inequalities in access to medical rehabilitation. Multiple linear regression and effect size calculation were used to show associations and to discuss the relation to clinical relevance. We were able to show a highly significant difference (P < 0.001) in access to exercise therapy in our study group. Patients aged 65+, women, single or widowed people, rehabilitants of low socioeconomic status or people located in the new federal states in Germany received shorter and less frequent exercise therapy. There are differences of up to 3.5 hours of treatment duration and 4.25 treatments per week, when disadvantaged social factors accumulate. However, despite the presented differences, the received treatments for the disadvantaged groups are still in the range of suggested minimum therapeutic requirements by the German Federal Pension Insurance. We could show a significant difference in rehabilitative therapy, which is solely based on social factors. There is an urgent need to draw special attention to the here discussed inequalities in access to medical rehabilitation for socially disadvantaged population and the overarching impact on society.• The social inequality in medical rehabilitation to the detriment of the socially disadvantaged population that we have identified must give rise to clear changes in order to establish social justice.• Equal opportunities and health quality assurance that address the individual needs of each patient should be the focus of socio-medical, policy development.


In a recent communication, Maselli and colleagues  supporteThese authors based their proposal on two studies. One is a randomized controlled trial (RCT) carried out in an academic emergency department (ED) in Canada, which randomized 78 people who accessed the ED for a minor MSKD. One group was evaluated by a physical therapist following a nurse triage under the supervision of an ED physician, and patients of the other group were evaluated by the ED physician . PatientRegardless of all of the biases related to the cited papers, it should be noted that they both analyzed populations from countries supporting the advocacy for direct access to PT, not for clinical reasons but for political and economic convenience ,5. AdditAs for the issue regarding the areas of autonomy of the physical therapists, in Italy, their involvement in prevention, care, and rehabilitation activities for people with disabilities, is always secondary to both the diagnoses and prescriptions performed by the physicians, including in private practices . It shouConcerning “Figure 1”, presented by the authors in favor of the direct access to PT, there are two conceptual/practical mistakes: the first mistake is in the referral to a medical specialist  for “further investigation ”, which is not the routine  ,10. The In our opinion, the most limiting aspect of the paper of Maselli et al. is the support of a dated “one-man show” approach , which contrasts with the modern interdisciplinary and multimodal approach  ,10,11,12Finally, we want to remind these authors that the concept of multidisciplinary rehabilitation approach is the basis of strengthening rehabilitation all over the world, as claimed by the WHO Rehabilitation 2030, a call for action .


Prostate cancer (PCa) is the second leading cause of cancer-related death in the US. Androgen receptor (AR) signaling is the driver of both PCa development and progression and, thus, the major target of current in-use therapies. However, despite the survival benefit of second-generation inhibitors of AR signaling in the metastatic setting, resistance mechanisms inevitably occur. Thus, novel strategies are required to circumvent resistance occurrence and thereby to improve PCa survival. Among the key cellular processes that are regulated by androgens, metabolic reprogramming stands out because of its intricate links with cancer cell biology. In this review, we discuss how cancer metabolism and lipid metabolism in particular are regulated by androgens and contribute to the acquisition of resistance to endocrine therapy. We describe the interplay between genetic alterations, metabolic vulnerabilities and castration resistance. Since PCa cells adapt their metabolism to excess nutrient supply to promote cancer progression, we review our current knowledge on the association between diet/obesity and resistance to anti-androgen therapies. We briefly describe the metabolic symbiosis between PCa cells and tumor microenvironment and how this crosstalk might contribute to PCa progression. We discuss how tackling PCa metabolic vulnerabilities represents a potential approach of synthetic lethality to endocrine therapies. Finally, we describe how the continuous advances in analytical technologies and metabolic imaging have led to the identification of potential new prognostic and predictive biomarkers, and non-invasive approaches to monitor therapy response. The unique dependency of PCa cells on androgen/androgen receptor (AR) signaling for their growth and survival is the basis for androgen deprivation therapy (ADT) as the first-line treatment in advanced disease. While ADT is initially effective, patients will eventually relapse within 18-24 months with a more aggressive form of the disease known as metastatic, castration-resistant prostate cancer (mCRPC), which is still incurable.Prostate cancer (PCa) is the most commonly diagnosed cancer and the second leading cause of cancer death in the US,3. However, their benefit is not long-lasting due to the occurrence of resistance mechanisms. These include AR gene/enhancer amplification, AR mutations leading to promiscuity, androgen-independent AR activation, coactivator overexpression, intratumoral de novo androgen synthesis, and overexpression of AR variants (AR-Vs), in particular AR-V7. Expression of AR-V7, which can now be reliably measured in circulating tumor cells, has become a critical biomarker for therapeutic decision-making. AR degradation through proteolysis targeting chimeras (PROTAC)  is currently under investigation to overcome mechanisms of castration resistance (CR)-9. While this approach is showing promising results, the downside of PROTAC-based therapy is the potential risk of developing neuroendocrine-like PCas, which are a very aggressive and fatal subtype.Despite ADT-induced castrate levels of circulating androgens, the AR signaling is still functional in CRPC, and AR remains the major target of ongoing therapeutic efforts. Currently in-use second-generation AR signaling inhibitors, which include the FDA-approved AR antagonist enzalutamide and the steroid synthesis inhibitor abiraterone acetate, have significantly improved CRPC patient survival and quality of life,11.While acquired knowledge on AR-mediated mechanisms of resistance has driven the design of AR-focused, more effective treatments, it has also raised awareness that AR-indirect and/or independent mechanisms may contribute to CRPC. In this context, evidence for PCa metabolic heterogeneity paralleling genomic and transcriptomic heterogeneity and the role of metabolic reprogramming in the acquisition of CRPC features have started to emerge-15. Finally, we provide a contemporary perspective on the emerging role of metabolomics and state-of-the-art metabolic imaging in identifying prognostic and predictive biomarkers. The goal of this review is to call attention on the role of metabolic reprogramming in CR, and on the need for carefully designed clinical trials to evaluate metabolic interventions alongside endocrine therapies.In this review, we describe how androgens modulate cancer metabolism and lipid metabolism, in particular, and how their deregulation sustains resistance to endocrine therapies. We explore the interplay between oncogenes, tumor microenvironment (TME), and cancer metabolism in promoting disease progression and CR. We then discuss the potential of targeting metabolic vulnerabilities to overcome resistance to endocrine therapies and the role that diet/obesity may play in PCa progression. The latter shows significantly different features between normal and PCa cells. Normal prostate cells accumulate zinc, which inhibits the enzyme m-aconitase required for the conversion of citrate to isocitrate in the tricarboxylic acid (TCA) cycle. The process is sustained by androgens that favor zinc uptake and results in a truncated TCA cycle with secretion of a high quantity of citrate, a major component of the prostatic fluid. In PCa cells, zinc is no longer accumulated, and citrate can be oxidized via TCA cycle to produce energy and anabolic substrates, including acetyl-CoA for de novo lipogenesis. Androgens regulate lipid metabolism mostly by promoting the expression and activation of sterol regulatory element-binding proteins (SREBPs), a family of transcription factors that bind to the promoter regions of genes involved in the synthesis, uptake and transport of fatty acids (FAs). Direct AR-binding sites have also been identified in the promoter region of FA synthase (FASN) gene, and a recent genome-wide analysis has suggested that AR direct regulation may extend to many other lipogenic enzymes. Thus, a combination of direct and indirect mechanisms is likely to be involved in AR-mediated control of FA metabolism.Androgens regulate cellular homeostasis, tissue differentiation, and maintenance of secretory functions of normal prostate cells. In PCa, however, the androgen/AR axis drives PCa cell growth and survival through the transcriptional regulation of many cellular processes, including cellular metabolism. Genetic/pharmacological perturbation of the AR axis confirmed androgen-regulation of lipid synthesis, largely via increased synthesis of FAs and cholesterol. The overexpression of lipogenic enzymes favors the production of lipids as building blocks for new membrane synthesis, fuel, storage, intracellular signaling and post-translational modifications of oncogenic proteins, and it provides the maintenance of redox balance and response to DNA damage-26, sustaining the fitness of cancer cells and their survival in a hostile microenvironment characterized by hypoxia and limited vascularity.Overexpression of lipogenic enzymes and accumulation of lipids has been documented in PCa cell lines, animal models, and human tissues using different methodologies, including biochemical approaches, radiolabeled tracers, nuclear magnetic resonance spectroscopy, histological staining, Raman spectroscopy and mass spectrometry (MS) imaging (MSI),29. The works of Watt et al., Tousignant et al. and Schlaepfer et al. were particularly instrumental in elucidating the role of androgen-mediated FA uptake and FA oxidation (FAO) in both PCa development and progression, with high expression of androgen-modulated FA transporters in the metastatic setting,31. In this context, it has also emerged that there is crosstalk between FA uptake, FAO and de novo lipogenesis, where a synergistic antitumor effect is achieved by their concurrent targeting,32. Moreover, Itkonen and coworkers identified enoyl-CoA-isomerase 2 (ECl2), a novel AR target involved in FAO, which was found overexpressed in PCa samples and associated with poor outcome.Following this initial observation, androgens have been reported to stimulate the expression of a multitude of enzymes involved in lipid synthesis, binding, uptake, transport and oxidation, thereby influencing the entire lipid profile of PCa cells in a fine-tuned mannerThese findings suggest a scenario where lipid metabolism in PCa is highly dynamic. It is likely that AR coordinates its actions with other transcription factors or oncogenes to establish or fine-tune specific metabolic programs. A better understanding of the androgen-mediated modulation of lipid synthesis/oxidation cooperation is crucial in the design of effective targeted therapies.de novo lipogenesis supports PCa development providing building blocks for membrane synthesis and signaling. Once tumors outgrow their vasculature network, oxygen and nutrients accessibility is compromised and PCa cells may favor FAO to support their viability. After dissemination, when oxygen and nutrients may again be available in the metastatic niche, PCa cells may adapt again their metabolism to favor aerobic glycolysis,35, while FAO and de novo lipogenesis still remain highly active .It is possible that . Thereafter, the overexpression of lipogenic enzymes in mCRPC has been documented using several human PCa datasets, especially in mCRPC overexpressing AR-V7 and resistant to treatment with AR signaling inhibitors . FASN was among the top ten genes overexpressed in AR-V7-high mCRPC, suggesting an interplay between AR-V7 expression and lipid metabolism deregulation. This was confirmed by AR cistrome analysis showing AR-mediated reactivation of FA synthesis during the progression to CRPC and the involvement of AR-V7.In 2004, Ettinger and coworkers for the first time observed increased expression of FA transcriptional modulators and lipogenic enzymes in the transition from hormone-sensitive to androgen-independent PCaet al. demonstrated the involvement of CPT1, the rate-limiting enzyme for FAO initiation, in CRPC onset and anti-androgen resistance through histone acetylation. These new findings have opened a scenario, still not completely characterized, where both FA synthesis and oxidation contribute to CR in a fine-tuned mannerIn 2019, the role for FAO in mediating CR also emerged. Joshi de novo lipid synthesis-43. Likewise, Schlaepfer et al. reported a significant decrease in AR-FL and AR-V7 as a result of FAO inhibition, highlighting for the first time the existence of a feed-forward loop also between FAO and AR signaling. These new findings have shifted the clinical perspective of targeting lipid metabolism in CRPC. Inhibitors of lipid metabolism are no longer merely repressors of an effector arm of AR oncogenic function, but they now offer a non-canonical approach to inhibit AR signaling and potentially overcome resistance to current standard of care, as we discuss below The original idea for a one-way regulation of lipid metabolism by androgens has been profoundly revised when groups including ours were able to achieve AR full-length (AR-FL) and AR-V7 downregulation following genetic and/or pharmacological inhibition of key lipogenic enzymes and transcription factors , suggesting the existence of a mutual regulation between AR and  (a phenomenon known as the Warburg effect). The use of aerobic glycolysis, which is energetically unfavorable, provides cancer cells with anabolic precursors for a rapid proliferation while still fulfilling energy demand, and thus providing a selective advantage to adapt and thrive in harsh environments. Moreover, lactate, once considered merely a waste product, is now considered a key oncometabolite involved in angiogenesis, migration/invasion, metastasis formation, immune evasion, and drug resistance. The discovery of a Warburg phenotype in tumors set the rationale for the use of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) in the diagnostic/prognostic clinical setting. However, unlike most solid tumors, primary PCa typically does not exhibit aerobic glycolysis and 18F-FDG-PET has shown limited utility in PCa detection. Glycolytic features have been nevertheless reported in high-risk PCa, where the acquisition of a Warburg phenotype marks a more aggressive disease. Pertega-Gomes et al. indeed observed a positive association between mRNA and protein levels of key glycolytic enzymes with worse clinicopathological features and biochemical recurrence (BCR). Accordingly, Choi and coworkers found high levels of lactate exporter monocarboxylate transporter 4 (MCT-4) protein in Gleason score (GS) 5 specimens, and again association with shorter time to develop BCR and CR. Accordingly, high intraprostatic 18F-FDG uptake in high-risk PCa patients was reported as an indicator of shorter BCR free survival and shorter time to CR following radical prostatectomy. These data support the potential use of preoperative 18F-FDG PET/CT as a non-invasive tool to distinguish patients in whom timely neo-adjuvant and adjuvant therapies should be explored.In 1920, the German biochemist Otto Warburg reported a marked increase in aerobic glycolysis whereby cancer cells increase consumption of glucose and its conversion to lactate even in the presence of oxygenet al. reported increased mRNA and protein expression of key glycolytic enzymes, including lactate dehydrogenase A (LDHA) and MCT-4 in mCRPC human specimens. Similar results were observed in the metastatic/CR TRAMP murine model by Bok and coworkers using hyperpolarized (HP) 13C magnetic resonance spectroscopic imaging (MRSI) and multi-parametric 1H magnetic resonance imaging (MRI).The acquisition of a Warburg phenotype in mCRPC has been actively studied. Pertega-Gomes . While evidence for the same mechanism occurring in human mCRPC still need to be provided, these preliminary findings suggest a role for aerobic glycolysis in PCa progression/CR establishment and support the exploration of targeting LDHA and MCT transporters as new therapeutic opportunities for mCRPC, as discussed below.The first mechanistic explanation for a Warburg phenotype in the metastatic setting was provided by Diedrich and coworkers using a preclinical model of bone metastasis. According to the authors, bone marrow-enriched fat cells promote aerobic glycolysis in metastatic PCa cells via oxygen-independent HIF-1α activation and consequent induction of glycolytic enzymesAltogether, FA and glucose metabolism rewiring appears to be a recurrent feature associated with CR and resistance to ADT/AR signaling inhibitors, calling for the need of testing glycolysis and lipid metabolism modulators in combination with standard of care, as discussed below.. Discordant results were, however, reported by Zacharias et al. using in vivo HP MRSI, as well as lactate measurements ex vivo. The authors reported increased lactate production in AR-dependent CRPC PDX models compared to AR-negative neuroendocrine PDX models, highlighting the need for further experimental work to fully elucidate the role of aerobic glycolysis in NEPC and the clinical potential of therapeutic approaches that target it.The role of aerobic glycolysis in neuroendocrine PCa (NEPC) has been the object of recent investigations. This very aggressive and lethal PCa subtype presents unique features, including loss of AR signaling during neuroendocrine transdifferentiation after treatment with AR-targeting anti-androgens, resulting in CR. Using patient-derived xenografts (PDXs), tumor tissues and gene expression data, Choi and coworkers reported enhanced glycolytic features associated with increased lactic acid production/secretion in NEPC. MCT-4 expression silencing in NEPC NCI-H660 cells was reported to inhibit cell proliferation, suggesting that elevated glycolysis coupled to excessive MCT4-mediated lactic acid secretion may be clinically relevant to NEPC. Consequently, targeting MCT4 might be worth testing as a new therapeutic strategy for NEPC. Unfortunately, other studies did not confirm sarcosine as a biomarker for aggressive PCa, most likely due to the technical difficulties to accurately measure sarcosine, and the difference in the study population. Thus, improvements in sarcosine detection and a careful design of prospective studies are still strongly needed before this biomarker can be used in precision medicine.The advent of metabolomics technologies has allowed for the unbiased interrogation of cancer metabolism and the identification of metabolic pathways involved in CR, previously uncharacterized. In 2013, the group led by Chinnaiyan used high-throughput liquid and gas chromatography-based MS (LC/GC-MS) to profile the metabolome of 262 clinical samples . Metabolic profiling was able to distinguish clinically localized PCa from mCRPC. Importantly, sarcosine, an N-methyl derivative of the amino acid glycine, emerged as a differential metabolite highly increased in mCRPC, and detectable non-invasively in urine. The authors went further to demonstrate AR binding to the promoter of the gene of glycine N-methyltransferase, the enzyme that coverts glycine into sarcosine, suggesting an interplay between AR and the sarcosine pathway. The year after, Shafi and al. reported an increase in glutaminolysis and reductive carboxylation in CRPC cell lines harboring AR-V7, suggesting their potential involvement in the resistance to endocrine therapies. More recently, the group of Freedland combined metabolomics and lipidomics in patient serum and identified reduction in steroid synthesis, ketogenesis and hyperglycemia as prominent hallmarks of ADT treatment, suggesting the potential use of restricted ketogenic diets in improving ADT-linked comorbidities. Altogether, these findings support a scenario where metabolic pathways other than FA and glucose metabolism may be altered in CRPC, suggesting the involvement of a more complex metabolic network in the acquisition of CR.Following this first study, several groups have investigated the metabolic changes that support CR acquisition. In 2014, Kaushik and coworkers used a combination of targeted MS and metabolic phenotyping and identified nineteen metabolites that were altered in androgen-independent compared to androgen-dependent cell lines. These altered metabolites mapped to a highly interconnected network of biochemical pathways that describe UDP glucuronosyltransferase activity and were associated with time to treatment failure. All these genetic alterations have been associated with resistance to endocrine therapies through different mechanisms, including metabolism reprogramming, highlighting the tight link between genetic drivers, metabolic alterations and CR. CR following PTEN loss has been associated with alterations in the metabolic flux of glycolysis, glutaminolysis, branched-chain amino acid catabolism and FA metabolism. The latter has gained special attention since Chen et al. demonstrated that co-deletion of PTEN and promyelocytic leukemia protein (PML) activates mitogen-activated protein kinase, resulting in a SREBP-dependent lipogenic program that promotes mCRPC. Concordantly, HFD triggered SREBP-dependent lipogenesis and induced metastasis in the nonmetastatic PTEN knockout (KO) model and further enhanced metastasis in the PTEN/PML KO model, suggesting the lipogenic program as an underlying rheostat toward metastatic PCa progression. More recently, PTEN loss has been associated with CR via intratumoral androgen synthesis triggered by the KT-RUNX2-OCN-GPRC6A-CREB signaling axis, resulting in the overexpression of the CYP11A1 and CYP17A1 genes.Genomic analyses showed the molecular heterogeneity of mCRPC. The most common alterations are AR amplifications/mutations (63%), p53 loss (53%) PTEN loss (50%), MYC amplification (18%), PI3K mutations (< 15%), BRAC1 and BRAC2 mutations (14.6%),61. MYC is overexpressed early in the disease and amplified in about 20% of mCRPC, and its transcript levels are increased in AR-V7-high bone metastases,62,63. MYC is an androgen-independent, AR-dependent targeted gene, whose protein overexpression induces androgen-independent PCa growth in preclinical models. Recently, two studies showed MYC involvement in AR-V7 stabilization and in the regulation of alternative splicing, linking MYC with the acquisition of resistance to endocrine therapies,66. In 2015, Mills and coworkers demonstrated MYC regulation of phosphoribosylaminoimidazole carboxylase (PAICS) and inosine monophosphate dehydrogenase 2 (IMPDH2), enzymes involved in de novo purine biosynthesis. High expression levels of the PAICS and IMPDH2 genes were reported in mCRPC, while IMPDH2 inhibition with mycophenolic acid sensitized the response to AR signaling inhibitors, suggesting a potential role for PAICS and IMPDH2 in mediating the resistance to endocrine therapies.The oncogene c-MYC  is a well characterized master metabolic regulator. MYC controls a wide range of metabolic pathways, including glycolysis, glutaminolysis, FA metabolism (both synthesis and oxidation) and protein synthesis,69. p53 was reported to directly bind to the promoter region of SREBP-1, inducing gene silencing and de novo lipogenesis inhibition. p53 inactivation was also associated with alterations in glucose, FA, oxidative phosphorylation, glutathione metabolism and inhibition of AR activity. In 2018, Maughan and coworkers showed that p53 status in the primary PCa is predictive of inferior response to AR signaling inhibitors in mCRPC, suggesting that p53 loss-associated metabolic alterations might be involved in the acquisition of resistance to AR signaling inhibitors.p53 is a tumor suppressor able to revert many of the metabolic effects exerted by MYC through inhibition of genes associated with glucose uptake, pentose phosphate shunt and nucleotide synthesis pathway. Whether BRCA 2 mutation status affects the response to AR signaling inhibitors is still an object of investigation. It has been reported that breast cancers harboring BRCA 1 mutations manifest a Warburg-like phenotype, which might also characterize BRCA 2-mutated mCRPC. Future investigations are required to explore this aspect.PCa patients carrying BRCA 2 mutations become resistant to ADT faster than non-carriersAs lipid metabolism rewiring, in the form of increased FA and cholesterol synthesis, uptake and oxidation, is a hallmark of mCRPC and resistance to endocrine therapies, efforts have focused on tackling enzymes and transporters involved in these processes.. This reality has recently changed with the development of TVB-2640, an orally available inhibitor of the FASN β-ketoacyl reductase domain. A phase I clinical trial has been recently completed proving the safety and efficacy of the drug in patients with advanced solid malignancies (NCT02223247). Combined with paclitaxel, TVB-2640 proved to be beneficial in heavily pretreated breast cancer patients, while the non-orally available analog TVB-3166 has shown promising results in preclinical models of mCRPC-80. Phase II trials are now investigating TVB-2640 in several solid tumor types  FASN, the key enzyme in the synthesis of FA palmitate, is certainly the most studied and the best characterized therapeutic target. However, despite the positive results in the preclinical setting, off-target effects, poor solubility and pharmacokinetics, and untoward side effects, including important weight loss, have hampered the clinical translationin vitro models through metabolic reprogramming and results in reduced protein expression and transcriptional activity of both AR-FL and AR-V7. Interestingly, FASN inhibition in mCRPC cells harboring AR-V7 downregulated especially the variant, suggesting a distinctive interplay between AR-V7 and de novo lipogenesis. Mechanistically, FASN inhibition triggered the activation of the endoplasmic reticulum stress response, resulting in reduced protein synthesis. Our analysis also demonstrated consistent inhibition of MYC and the MYC-mediated transcriptional program, following FASN suppression. As mentioned above, MYC promotes CR and AR-V7 stabilization and competes with AR for binding to AR-regulated genes. Thus, the opportunity to repress AR/AR-V7 and MYC signaling simultaneously is particularly attractive in the mCRPC setting. In vivo, IPI-9119 reduced the growth of AR-V7-driven mCRPC xenografts and human mCRPC-derived organoids. IPI-9119 and enzalutamide combination induced higher mCRPC cell growth inhibition than single treatment. Thus, FASN targeting represents a non-canonical approach to inhibit AR/AR-V7 signaling and to improve the activity of AR signaling inhibitors. In human mCRPC, FASN was co-expressed with AR-FL in 87% of metastases and with AR-V7 in 39% of bone metastases. In patients treated with enzalutamide and/or abiraterone, FASN/AR-V7 double-positive metastases were found in 77% of cases, providing a compelling rationale for the use of FASN inhibitors in mCRPCs. We envisage that IPI-9119 could be combined with AR signaling inhibitors in AR-V7-negative CRPC to delay/overcome resistance. Alternatively, FASN inhibition could be undertaken in tumors (AR-V7-positive) once resistance has already emerged and further therapeutic options are scarce. Carefully designed clinical trials are required to establish the therapeutic timing, combinatorial regimens and the suitable population to treat.In the context of mCRPC, our group characterized a new small-molecule FASN inhibitor (IPI-9119) and demonstrated that selective FASN inhibition antagonizes the growth of mCRPC in .Inhibition of HMGCR, a key enzyme in the mevalonate pathway for sterol biosynthesis, is currently being tested in a phase 3 clinical trial. This double-blind placebo-controlled trial, currently recruiting patients, is designed to test whether atorvastatin (an HMGCR inhibitor) delays the development of CR during ADT in metastatic or recurrent PCa (NCT04026230). In the preclinical setting, HMGCR inhibition with simvastatin enhanced the efficacy of enzalutamide-based therapy and decreased AR/AR-V7 protein levels via inhibition of the mTOR pathwayP < 0.00001) and cancer-specific mortality  in advanced PCa patients treated with ADT, whereas inconsistent results were obtained with AR signaling inhibitors. Thus, future studies are still required to establish the efficacy of statins in combination with AR signaling inhibitors in mCRPC patients.The clinical translation of statins in oncology has been easier than for other compounds since they are relatively safe and already used for the treatment of hypercholesterolemia in patients. A recent meta-analysis evaluated the effects of statin use on treatment outcomes  among patients with advanced PCa treated with ADT or AR signaling inhibitors. Statin use was associated with lower risk of all-cause mortality -AR feedback mechanism. The combination of ACLY inhibitor BMS-303141 and enzalutamide promoted energetic stress and AMPK activation, resulting in further suppression of AR levels and target gene expression, inhibition of proliferation, and apoptosis. These data suggest that the ACLY-AMPK-AR network could be exploited to sensitize CRPC cells to AR antagonism. Unfortunately, no ACLY inhibitors have reached the clinical level so far Targeting ACLY, the enzyme that converts citrate to acetyl-CoA for FA synthesis, has shown promising results in the preclinical setting,84, but again, none of the available ELOVL inhibitors has been suitable for clinical studies.Promising results have also been obtained by gene silencing of ELOVL 5 and 7. Combinations of FAO inhibitors  and enzalutamide were tested in mCRPC cell and xenograft models. The effects of the combinations were very strong with the irreversible inhibitor etomoxir and robust, albeit less potent, with ranolazine and perhexiline. While the clinical translation of etomoxir has been terminated due to the toxic side effects (mostly hepatotoxicity), ranolazine and perhexiline are already approved in Europe, US, and Australia for the treatment of heart diseases, thus opening a potential safe avenue for the combinations of FAO inhibitors and AR signaling inhibitors As mentioned above, targeting FAO as a therapeutic approach in mCRPC has recently gained interest. Iglesias-Gato and coworkers performed a proteomics analysis and identified a subgroup of bone metastases characterized by elevated expression of many canonical AR targets and FAO enzymes, highlighting the need for adequate patient stratification when metabolic therapies are considered as therapeutic approach,87,88. LDHA knockdown or inhibition with the compound FX11 was particularly effective in the treatment of ATM-deficient CRPC cells, suggesting that targeting glycolysis may be beneficial for patients with PARP inhibitor-resistant mCRPC. The NADH-competitive LDHA inhibitor gossypol (AT-101) is currently tested in patients with newly diagnosed metastatic PCa and CRPC . The drug is relatively safe and effective in reducing tumor markers; however, it lacks selectivity. The drug was indeed reported to antagonize the anti-apoptotic BCL2 family of proteins by acting as a BH3 domain mimetic, and thus, the antitumor properties observed with AT-101 are likely due to suppression of both targets. Regarding MCT inhibitors, AstraZeneca has recently developed a specific MCT-1 inhibitor (AZD3965) that is currently in a phase 1 clinical trial (NCT01791595), while MCT-4 inhibitors are still in the discovery phase While the majority of efforts have been focused on lipid metabolism, the therapeutic potential of inhibiting the Warburg phenotype of mCRPC (see above) is currently in the limelight. Genetic silencing or pharmacological inhibition of LDHA or lactate transporters MCT-1/MCT-4 showed promising results in mCRPC cell lines and murine models. Mishra and coworkers identified epigenetic changes in CAFs that promote a cascade of stromal-epithelial metabolic interactions and facilitate lethal PCa growth and ADT resistance. Two independent studies also highlighted the existence of a metabolic crosstalk via the lactate shuttle between PCa cells and CAFs to sustain cancer aggressiveness. Ippolito et al. reported increased release and uptake of lactate from CAFs and PCa cells, respectively, resulting in lactate oxidation and alteration of NAD+/NADH ratio in PCa cells, followed by SIRT1-dependent PGC-1α activation, increased mitochondrial activity, superoxide generation and growth advantage. Accordingly, Pertega-Gomes observed the expression of MCT-1 and MCT-4 lactate transporters in the epithelium and stromal compartment of human PCa tissues, respectively. High stromal MCT-4 and high epithelial MCT-1 were associated with poor outcome, highlighting the clinical relevance of this lactate shuttle in the clinical setting.Recent insights into the critical role of TME in disease progression underscored the need to investigate how metabolic reprogramming in cancer-associated fibroblasts (CAFs), adipocytes and infiltrating immune cells contributes to disease progression and resistance to ADT/AR signaling inhibitors. Several studies have been conducted to address this aspect. Valencia and coworkers documented a reduction in p62 levels in PCa stroma. The authors proposed that tumor epithelial cells favor the downregulation of p62 in CAFs leading to reduced mTORC1 activity and c-Myc expression, impaired metabolic detoxification, and release of IL-6 with subsequent promotion of epithelial tumor growth and invasionWhile still in its infancy, a better understanding of the metabolic crosstalk (metabolic symbiosis and antagonism) between TME and PCa cells might thus be critical in identifying novel mechanisms of CR and vulnerabilities that can be exploited therapeutically.The integration of patient-derived explants, PDX models and stroma/epithelium co-culture models using human PCa organoids will be crucial in elucidating the metabolic interactions between PCa cells and TME in systems that more closely recapitulate PCa heterogeneity and complexity.. A recent paper demonstrated that this association occurs regardless of race. Whether unhealthy diets, especially fat-rich ones promote PCa progression is still a matter of debate, despite that is has been consistently observed in preclinical models,40. Inconsistent results in human studies may be due to population selection and/or difference in dietary interventions between studies.Several epidemiological studies have documented the association between obesity and lethal PCa.Both obesity and sustained consumption of fat-rich diet alter the nutrient gradient in the TME, which may favor cancer cells/TME metabolic symbiosis, inflammation, cancer progression and chemoresistanceet al. demonstrated that a saturated FA-enriched diet was sufficient to promote mCRPC in a nonmetastatic PTEN-null model via an aberrant lipogenic program orchestrated by the transcription factor SREBP. Consistently, our group demonstrated that increased intake of saturated FAs enhances a c-MYC-mediated oncogenic transcriptional program, which is associated with lethality in patients. In 2004, Ngo and coworkers showed that reduced dietary fat intake delays the progression to CRPC in xenograft models and prolongs survival, suggesting low-fat diet as a promising adjuvant intervention during ADT. The impact of a carbohydrate rich-diet on PCa progression has also started to be recently investigated. Freedland and coworkers reported a randomized controlled trial (CAPS1) where the combination of a low carbohydrate diet (LCD) (≤ 20 g carbohydrate/day) plus walking (≥ 30 min for ≥ 5 days/week) was an effective strategy for blocking ADT adverse metabolic effects. In a second study (CAPS2), the same authors reported exploratory findings of longer PSA doubling time under LCD compared to control in patients with BCR, calling for larger studies testing LCD on disease progression. Clinical trials are currently ongoing to evaluate the efficacy of fat- and sugar-restricted diet on PCa progression and mCRPC treatment. Results from these studies will be valuable to determine whether nutrition intervention has a beneficial effect on PCa progression and whether it should be implemented in the management of PCa patients prior to or along with ADT/AR signaling inhibitors.As previously outlined, Chen .Furthermore, when targeting lipogenic enzymes is considered a potential therapeutic approach, nutritional parameters and obesity status should be recorded to monitor for potential lipid uptake compensation due to increased systemic and TME nutrient availabilityThe success of targeted therapies lies on the selection of patients most likely to respond and the timely evaluation of therapy response in a non-invasive manner. The last decade has seen enormous progress in the application of metabolomics and metabolic imaging to identify biomarkers of disease aggressiveness and response to ADT/AR signaling inhibitors et al. described thirty-three human case-control studies. All but one demonstrated the ability of metabolite profiling in correctly identifying cancer vs. benign, tumor by aggressiveness, cases that recurred, and those that responded well to therapy. Biomarker discriminatory ability was quantified for some metabolites, reporting areas under the curve that would potentially outperform the current gold standards. Following the work of Kelly et al., Kandra and coworkers provided an updated analysis that included fifty-nine studies. Some discriminative metabolites of PCa disease were reported across various technical approaches, cohorts and sample types, suggesting their potential clinical relevance. Glycine, in particular, was repeatedly increased in both biological fluids and tumor tissues of PCa patients, requiring further investigation as potential diagnostic biomarker. So far, only few studies focused on metabolic biomarkers of disease progression and treatment response to ADT have been conducted. Lower levels of citrate and spermine in PCa tissues were found predictive of worse prognosis, while deoxycholic acid, glycochenodeoxycholate, docosapentaenoic acid, tryptophan, arachidonic acid, the nucleotide deoxycytidine triphosphate and pyridinoline were identified as potential biomarkers for predicting response to ADT. Caution, however, must be taken in interpreting these studies. Lack of replication and validation remains the biggest limitation in the field of metabolomics, an issue that has prevented the use of metabolic biomarkers in the clinical routine so far. Moreover, pre-analytical and technical obstacles, statistical artifacts and confounding factors are still unresolved issues. Carefully designed future studies with appropriate sample size, controls in place at the pre-analytical, analytical, and clinical stage, and finding validation using an appropriate set of independent samples are absolutely required prior the integration of metabolomics in the practice of precision medicine.Two recent systematic reviews have summarized the results of current efforts in using metabolomics to identify predictive, diagnostic, prognostic and treatment response biomarkers. Kelly et al. performed LC/MS- based lipidomic profiling on plasma samples from a discovery cohort of CRPC patients and validated the results in an independent cohort. Unsupervised analysis of lipidomic profiles classified the discovery cohort into two subgroups with significant survival differences . Forty-six lipids, predominantly sphingolipids, were associated with poor prognosis. The authors were able to derive and validate a prognostic three-lipid signature  as independent prognostic factor. Moreover, the group of Butler used lipidomics to profile PCa cell lines, xenografts and patient-derived explants under treatment with androgen and AR signaling inhibitors. The authors identified changes in lipid elongation for multiple phospholipid classes in response to androgen treatment, which was reversed by enzalutamide, suggesting the utility of lipidomics to predict response to endocrine therapies.Despite the crucial role of lipid metabolism in PCa progression and resistance to endocrine therapies, lipidomics studies have only recently been reported in the literature, most likely due to the methodological challenge of analyzing simultaneously diverse lipid classes and molecular species. However, these studies are now becoming increasingly popular in the field of biomarker discovery. Lin . Given the promising results with MALDI-MSI, this technology holds great promise in the identification of predictive biomarkers to ADT response by interrogating both cancer epithelium and stroma compartment. Advances are also being made in “omics” integration and, more recently, in spatial metabolomics and transcriptomics integration-109. While still challenging, metabolomics/transcriptomics integration could offer data-driven system approaches to refine our understanding of mechanisms of CR.While the high resolution, sensitivity and specificity of LC/MS-based metabolomics and lipidomics have favored their use in biomarker discovery, these technologies, which analyze metabolite extracts, fail to provide spatial information, preventing the possibility to interrogate cancer biomarkers in relation to tissue pathology and compartment distribution. The development of MSI has overcome this limitation, allowing the overlap of metabolic and pathology information on the same tissue section. MSI thus represents an important step forward for the evaluation of metabolic reprogramming occurring in the TME. Matrix-assisted laser desorption ionization (MALDI)-MSI, where the sample is mixed with a UV-absorbing crystalline matrix material and ionized by the laser beam, is the most commonly used MSI method. Our group has recently applied MALDI-MSI to investigate prognostic biomarkers in prostatectomy samples with GS of six to nine. A gradient of changes in the intensity of various lipids was observed, which correlated with increasing GS. Moreover, a total of thirty-one lipids, including several phosphatidylcholines, phosphatidic acids, phosphatidylserines, phosphatidylinositols, and cardiolipins were able to discriminate GS (4+3) from GS (3+4) cases, suggesting their potential clinical relevance in predicting more aggressive/lethal PCa in intermediate risk cases based on pathologyet al. have been at the front line in the application of MRSI in PCa. The advantage of this technology with respect to MSI is that it can be applied both ex vivo and in vivo in tandem with MRI. Compared to PET which measures the retention of a single radiolabeled metabolite, 1H-MRSI  is a radiation-free technique that allows in vivo measurement of a complete spectrum of measurable metabolites to distinguish tumor areas, inform on cancer aggressiveness, and monitor therapy response. The detection of high choline (Cho) and creatine (Cr) levels and reduced citrated (Cit) and polyamines measured by 1H-MRSI has been used for years to support PCa diagnosis using multiparametric MRI, where Cho+Cr/Cit magnitude is a parameter of disease aggressiveness.In the context of non-invasive imaging biomarkers, Kurhanewicz 13C-labeled metabolic substrates for the rapid and non-invasive monitoring of dynamic pathway-specific metabolic processes. Hyperpolarization, achieved through the dynamic nuclear polarization technique, provides unprecedented gain in sensitivity  for imaging 13C-labeled biomolecules that are endogenous, nontoxic and nonradioactive. Metabolically active HP 13C-labeled compounds can be delivered to living systems where the substrate is metabolized, and the products can be imaged in real time. While the metabolism of primary PCa is inadequately evaluated using 18F-FDG PET (which measures glucose uptake and phosphorylation), HP 13C-MRSI detects downstream metabolism, specifically the conversion of HP [1-13C] pyruvate to [1-13C] lactate catalyzed by LDHA. The authors reported the first-in-human phase 1 clinical study of HP 13C-pyruvate MRSI in patients with PCa on active surveillance and confirmed the feasibility of capturing regions of accelerated HP pyruvate-to-lactate flux in high-grade vs. low-grade cancer vs. benign tissue. Most recently, the same group used HP 13C-pyruvate MRI in patients with mCRPC and described the feasibility of assessing metabolic response to ADT. Strikingly, these authors showed the ability of HP 13C MRI to detect early metabolic responses before such a response could be ascertained using standard radiographic criteria. These findings highlight the great potential of using HP-MRSI and MRI to non-invasively monitor early response to endocrine therapies in PCa patients. A prospective imaging study evaluating the utility of baseline metabolic MRI with HP 13C-pyruvate as a predictive response biomarker to AR signaling inhibitors in CRPC patients is currently ongoing (NCT02911467).Dr. Kurhanewicz has also pioneered the development and clinical translation of an improved MRSI technology utilizing hyperpolarized (HP) 11C-choline- and 11C-acetate-based PET has also shown promising results in detecting recurrent disease and in monitoring response to ADT,117 and it can very be useful in future studies, particularly in evaluating response to anti-lipogenic drugs and ADT combination.While limited by the use of radiotracers and the need of a cyclotron for radiotracer synthesis, The identification of a mutual interplay between cell metabolism reprogramming and AR signaling has opened new opportunities in mCRPC treatment and in monitoring the response to endocrine therapies. In this new scenario, we foresee the use of metabolomics approaches for patient stratification, the use of metabolic modulators in combination with standard of care to overcome drug resistance, and the use of metabolic imaging to predict and to monitor, non-invasively, therapy response. Successful therapeutic strategies also need to take into account TME heterogeneity and the dynamic changes in nutrient gradients, particularly in response to therapy. The use of accurate models that more faithfully resemble tumor heterogeneity such as patient-derived explants, PDX, and stromal co-culture with human organoids will be critical in defining the benefits of targeting metabolic pathways along with ADT or AR signaling inhibitors.Well-designed clinical trials with sufficient statistical power and adequate validation are also in urgent need to elucidate whether obesity and the consumption of unbalanced diets may alter the response to ADT or AR signaling inhibitors and contribute to the acquisition of CR.In a time where metabolic drugs have finally reached the clinical setting and metabolomics and imaging technologies are constantly improving, we are seeing the exciting opportunity to evaluate the modulation of cancer metabolism as a strategy to improve the management of mCRPC patients.


Finally, we further demonstrate that AR inhibitor epalrestat is neuroprotective against BPRA injury by increasing autophagy level, alleviating neuroinflammation and rescuing MNs death in mice. Collectively, our data demonstrate that the AR upregulation in the spinal cord is an important factor contributing to autophagy disruption, neuroinflammation and MNs death following brachial plexus roots avulsion in mice. Our study also provides a promising therapy drug to assist re-implantation surgery for the treatment of BPRA.Brachial plexus root avulsion (BPRA) is frequently caused by high-energy trauma including traffic accident and birth trauma, which will induces massive motoneurons (MNs) death as well as loss of motor and sensory function in the upper limb. The death of MNs is attributed to energy deficiency, neuroinflammation and oxidative stress at the injured ventral horn of spinal cord triggered by BPRA injury. It has been reported which aldose reductase (AR), an endogenous enzyme that catalyzes fructose synthesis, positively correlates with the poor prognosis following cerebral ischemic injury, diabetic retinopathy and diabetic peripheral neuropathy. However, the role of AR in BPRA remains unknown. Herein, we used a mouse model and found that in the spinal cord of BPRA mice, the upregulation of AR correlated significantly with (1) an inactivated SIRT1–AMPK–mTOR pathway and disrupted autophagy; (2) increased byproducts accumulation of lipid peroxidation metabolism and neuroinflammation; and (3) increased MNs death. Furthermore, our results demonstrated the role of AR in BPRA injury whereby the absence of AR (AR knockout mice, ARThe online version contains supplementary material available at 10.1186/s12974-022-02632-6. Brachial plexus roots avulsion (BPRA), mainly resulting from road traffic accidents or difficult childbirths, causes upper limb motor and sensory impairments which in turn seriously affects patient quality of life . Motor nThe pathophysiological sequelae of primary avulsion injury in the spinal cord include ion homeostatic disequilibrium, heightened glutamate excitotoxicity, energy deficiency, disruption of normal mitochondrial function, and integrity of micro vessels, leading to organelle damage, toxic protein aggregation and progressive MNs loss . AutophaBesides, another important hallmark of BPRA is neuroinflammation in the injured spinal cord, which is one of the indispensable processes related to the aftermath of nervous tissue damage as well as regeneration . In addi+-dependent enzyme sorbitol dehydrogenase oxidizes sorbitol into fructose. Therefore, AR will deplete cellular NADPH and elevate cytosolic NADH/NAD+ ratios, which will reduce the activity of NAD+-dependent deacetylase Sirtuin-1 (SIRT1) [AR belongs to the aldo–keto reductase (AKR) superfamily. The NADPH-dependent AR is the sole enzyme that catalyzes the metabolism of excess glucose into sorbitol via the polyol glucose metabolism pathway . Moreove (SIRT1) . Further (SIRT1) . Subsequ (SIRT1) .However, there are few studies evaluating the role and the plausible molecular mechanisms of AR in the context of BPRA and MNs survival. In this study, we demonstrated elevated levels of AR concomitant with neuroinflammation, disrupted autophagy and MNs death in BPRA mice model. Additionally, we established a causal role of AR in MNs death using the AR knockout mice subjected to BPRA. Finally, we provided a proof of concept that pharmacological inhibition of AR is a potential therapeutic strategy to attenuate MNs death in BPRA.−/−) in our stock were generated as described previously [+/+). The wild-type mice were purchased from the Laboratory Animal Center of Sun Yat-sen University, Guangzhou city in China. The experimental animal use permit number is SYXK 2017-0081. The AR inhibitor epalrestat  was administrated by daily (afternoon) oral gavage for 14 days to mice after receiving BPRA injury [AR gene knockout mice . Their blood was washed out by transcardial perfusion with 0.9% normal saline and then fixed with pre-cooled 4% paraformaldehyde in 0.1 M phosphate buffer (pH 7.4). Bilateral laminectomy was carried out under a dissection microscope to expose the C7–C8 spinal segments. The segments of interest were carefully dissected out and post-fixed in 4% PFA for 3–4 h followed by overnight immersion in 30% (v/v) sucrose in PB solution in a fridge set at 4 °C. 30-μm transverse sections of the C7–C8 segments were cut on a freeze microtome and every third section was collected into 0.01 M PBS for use in staining described below.At several time points  following BPRA, the mice were anaesthetized using an intraperitoneal injection of 1% sodium pentobarbital . An incision was made on the dorsal part of the next to expose the muscles and separate them. A bilateral laminectomy was then performed under a dissection microscope to expose the C5 to T1 spinal segments. The segments were rapidly dissected off and immediately frozen in liquid nitrogen for the ease of division into ipsilateral and contralateral halves. The cut spinal cord segments were then stored in liquid nitrogen until needed for PCR, WB and ELISA. For histology studies, the roots avulsed mice were killed as mentioned above at days 1, 3, 7 and 14 dpi  was used for immunofluorescence evaluations. The spinal cord slices were rinsed thrice in PBS and then incubated in 0.3% Triton X-100/0.1% bovine serum albumin for half an hour at room temperature. The slices where then incubated with the following primary antibodies; mouse anti-NeuN (Abcam UK), rabbit anti-GFAP , rabbit anti-IBA-1 , rabbit anti-Cleaved Caspase-3 , rabbit anti-Bcl-2 , rabbit anti-AMPKα , rabbit anti-Beclin1 , rabbit anti-GAP43 , rabbit anti-mTOR , rabbit anti-p-mTOR , rabbit anti-p-CREB , rabbit anti-LC3B , rabbit anti-SIRT1 (Abcam UK), rabbit anti-P62 (Abcam UK), rabbit anti-4-HNE (Abcam UK), rabbit anti-p-AMPKα (Abcam UK), mouse anti-Arginase1 (Santa Cruz Biotechnology Inc USA), goat anti-CD16/32 (R&D Systems Inc USA) and goat anti-ChAT  These slices were incubated with primary antibodies at 4 °C overnight. The slices were then washed thrice with PBS, and then incubated in darkness with the following secondary antibodies for 1–2 h at room temperature; goat anti-mouse with Alexa Fluor-488 (Invitrogen USA), goat anti-rabbit with Alexa Fluor-555 (Invitrogen USA), donkey anti-goat with Alexa Fluor-488 (Invitrogen USA), and donkey anti-rabbit with Alexa Fluor-555 (Invitrogen USA). After the secondary antibody incubation, the slices were rinsed thrice in PBS and then incubated in Hoechst 33,342 . Finally, the slices were air-dried, cover-slipped and observed under a fluorescence microscope. Omitting of either a primary or secondary antibody was used as a as a negative control. We calculated the mean number of immunoreactive cells from the total 10-immunofluorescence sections serially obtained from each mice (Every third sections from each mice used for staining and counting). The immunoreactive cells were quantified under the 20 × magnification in six circular areas of 100 μmrotocols .n = 5 mice). The deeply anesthetized mice were transcardially perfused using 0.9% normal saline until the exudate was clear of blood stain and then fixed using a mixture of 2% PFA and 2.5% glutaraldehyde  in 0.1 M PBS. A 1 mm3 piece of ventral horn grey matter tissue located in lamina IX of Rexed per mouse was cut off and post-fixed in 2% glutaraldehyde for another 2 h at 4 °C. The glutaraldehyde-fixed tissue was then washed thrice in 0.1 M cacodylate buffer and further post-fixed in 1% osmium tetroxide for another 2 h. After three rinses in distilled water, the pieces were then dehydrated in a graded series of ethanol concentrations. A half-acetone and half-resin mixture was used to infiltrate the tiny tissue pieces overnight at 4 °C. The tissues were embedded in resin and then cured under the following settings: (1) 37 °C overnight, (2) 45 °C for 12 h, and (3) 60 °C for 24 h. Afterward, a vibratome was used to obtain 70-nm thin sections which were then stained with 3% uranyl acetate for 20 min followed by 0.5% lead citrate for 5 min. Ultrastructural changes in the motor neurons were evaluated under the transmission electron microscope  operated at 100 kV.Transmission electron microscopy (TEM) was used to evaluate mitochondrial and autophagosome morphology in the spinal cord motor neurons following brachial plexus roots avulsion , IL-6 , ICAM1  and IL-10 Mouse IL-10 Quantikine ELISA Kit, M1000B), which were all from R&D Systems. The assays were performed according to the manufacturer’s instructions.−ΔΔct method and was normalized to the control gene GAPDH. Messenger RNA expression differences between the avulsion groups and sham operated group were compared using Student’s t-test in SPSS (IBM SPSS Inc Version 22.0 USA). A p-value less than 0.05 was deemed statistically significant.TRIzol Reagent (Invitrogen) was used for Total RNA extraction following recommended procedures laid down by the kit manufacturer. RNA concentration and purity (260/280 ratio) were measured using UV spectroscopy. The total RNA was reverse-transcribed using the Fast Quant RT Kit (with gDNase)  following the manufacturer’s recommended steps. Then, real-time PCR was performed using SYBR Green assays  according to the manufacturer’s instructions. All primers used in this study are listed in Table An electric homogenizer was used to process frozen ventral horn tissue samples in a whole-cell lysis buffer (Key GEN Biotech) mixed with a protease inhibitor and 1 mM PMSF (Sigma–Aldrich). The homogenates were left on ice for 1 h and then centrifuged at 12,000 rpm for 30 min at 4 °C. The resultant supernatants were pipetted out into new tubes. A small amount from each tube was used for protein concentrations using the BCA (Thermo Scientific) method. Equal amounts of protein from each sample were then run through the 10% SDS–PAGE and electro-transferred onto respective polyvinylidene fluoride (PVDF) membranes  using Transblot Turbo  at 300 mA for 1 h. The membranes bearing electro-transferred proteins were incubated with 5% nonfat milk/Tris buffer containing Tween-20 buffer  for 2 h at room temperature. The strips corresponding to target proteins’ molecular weights were then incubated in the primary antibodies, listed in the immunofluorescence method section, at 4 °C overnight. The membranes were then washed thrice with TBST (10 min each) and then probed with the corresponding secondary antibodies conjugated with horseradish peroxidase  at room temperature for 2 h. The membranes were then washed thrice for 10 min each using TBST remove unbound secondary antibodies and then visualized using enhanced chemiluminescence . The densities of specific bands were measured using ImageJ software’s densitometry feature and normalized against a loading control (GAPDH).p < 0.05 was considered to be statistically significant.All data are expressed as the mean ± standard error of the mean (SEM). The data were analyzed to one-way or two-way ANOVA, as appropriate, and then followed by a Bonferroni or Tukey post hoc test for statistically significant results. A Generally, AR is hardly expressed in the normal tissue. However, there are upregulations of AR expression following stroke, non-alcoholic fatty liver disease, diabetic retinopathy as well as diabetic peripheral neuropathy , 19–21. −/−) alleviated MNs death in the model of BPRA mice. Initially, we examined the effect of AR deficiency on MNs survival by staining neutral red, and the survival rate of injured MNs was assessed as the ratio of ipsilateral ventral horn neutral red-positive MNs to those on the contralateral ventral horn [−/− group was higher than WT group at 3, 7 and 14 dpi on the ipsilateral ventral horn of the spinal cord. Furthermore, AR−/− mice exhibited an increase in NeuN and anti-apoptosis gene Bcl-2 colocalization-positive neurons on the ipsilateral ventral horn of the spinal cord at 1–14 dpi . During this delivery, the adapter protein (p62) is also degraded by autophagy alongside its cargo. Therefore, the accumulation of p62 suggests that autophagic degradation has been disrupted. Compared with BPRA WT mice, AR−/− mice following BPRA. The structures of typical autophagic vacuoles are shown under high-magnification  EM  to evaluate autophagic vacuoles number of MNs in both WT and ARice Fig. E. These −/− mice. We first examined mitochondrial morphology and size by transmission electron microscopy and observed that there were larger mitochondria with altered crista organization in MNs from WT mice when comparing with those in AR−/− mice following BPRA  and class II (12.4%), class III (6.1%), class IV (3%)  microglia at 3–14 dpi  microglia at 1–14 dpi on the ipsilateral ventral horn of the spinal cord  plays a key role in anti-inflammatory microglial phenotypes and AR can reduce 4-HNE into GS-DHN, a macrophage inflammatory mediator, we estimated whether genetic ablation of AR acts via 4-HNE–p-CREB signaling to exert its “phenotype switching” effect following BPRA injury , 27. Theury Fig. A–D. ThesEpalrestat (EPAL), a pharmacological AR inhibitor with protective effects against diabetic complications in mouse models and human clinical trials , was useBPRA injury is mainly caused by motor vehicle accident and birth trauma. Severe BPRA can lead to partial or complete loss of motor and sensory functions of the upper limb because of massive MNs death, motor axon degeneration and de-innervation of targeted muscles. The novel finding of our study is that AR expression is markedly upregulated in the BPRA mice model. Importantly, the role of AR following BPRA is investigated by using AR gene knockout mice and inhibiting its activity pharmacologically with AR inhibitor epalrestat. Our date reveals that genetic knockout or epalrestat pharmacological suppression of AR contributed to better MNs survival by attenuating BPRA-induced autophagy disruption and neuroinflammation. These findings cast AR as a potential therapeutic target in BPRA injury treatments and that AR inhibitors could be a promising strategy for mitigating against BPRA caused MNs death.+ abundance and the NAD+/NADH ratio. The actual relationship between AMPK and SIRT1 need us examine the LKB1 activity and NAD+ abundance in the future study. At present, our findings implied that suppression of AR could enhance SIRT1–AMPK–mTOR signaling and autophagy level following BPRA injury.Autophagy is a lysosome-dependent intracellular degradation process that eliminates long-lived proteins as well as damaged organelles. An increasing number of evidence suggests that dysregulation of autophagy plays a pivotal role in the progression of neurodegenerative diseases including motor neuron disorders. Our data suggest that BPRA will cause MNs autophagy dysregulation and MNs death. Moreover, heightened levels of P62 and reduced levels of LC3II found in BPRA mice model were associated with MNs death. Notably, autophagy could prevent the accumulation of damaged macromolecules and organelles to maintain function and survival of MNs. Importantly, in AR-deficient mice (AR-/- or EPAL treatment), the ratio of LC3BII to LC3BI was significantly increased, while the level of P62 was significantly decreased, suggesting that AR suppression may enhance autophagy level and maintain MNs survival. In an earlier study, SIRT1 could protected cardiomyocytes against hypoxia-induced apoptotic death in a mechanism via autophagy and AMPK activation. AMPK, a serine/threonine kinase, senses changes in, and regulates cellular energy homeostasis. When activated, it promotes autophagy by inhibiting mTOR . Both AM−/− mice after BPRA injury, the exact mechanism of autophagy, its regions and cell-type specificity remained unknown. In a previous spinal cord injury study [+ microglia according their cell morphology. In the white matter, LC3 accumulated in CC1-positive oligodendrocytes both in dorsal and ventral white area. However, unlike microglia and oligodendrocytes, the number of LC3-positive astrocytes remained very low in all regions at all time points examined. According to our previous and present study [Our IHC studies come from ipsilateral ventral horn only, while WB studies were used to analyze the protein expression levels in all the cells  from ventral horn and dorsal horn on the ipsilateral side of spinal cord. Although our results showed elevated autophagy level in ARry study , the expnt study , BPRA in−/− mice. These findings demonstrate that AR plays an important role in the divergence of microglial/macrophage functions after BPRA injury in mice.Inflammation is among the very crucial pathological processes in the secondary injury phase after BPRA injury. Resident microglia and hematogenous macrophages, invade the injury site shortly after the primary injury . The infm values (in the micromolar range of 10 to 30 μM) compared with that of glucose (50 to 100 mM) [Recently, several reports revealed that AR mediates LPS-induced inflammatory signals in macrophages . Suppres 100 mM) . Therefo 100 mM) . TherefoAR inhibitors have been under investigation for approximately four decades, although most of them are used in diabetic neuropathy and retinopathy . EpalresThese findings reveal that AR is a contributor to the BPRA pathogenesis, and AR deficiency is neuroprotective in mice subjected to BPRA. In the future, the cell type-specific AR knockouts could enhance our understanding of the actual function AR in those cells or tissues following BPRA or other neurodegeneration diseases. On the basis of results, we also consider epalrestat as a feasible pharmacological agent to attenuate MNs death after BPRA. Further biomedical studies and clinical trials are required to test the safety and efficacy of such AR inhibitors in BPRA patients.Additional file 1: Figure S1. The AR−/− mice genotyping and the expression level of AR in AR−/− mice. (A) AR null allele were identified by northern blot analysis. The expected bands of ∼119 bp is observed in the wild-type mice while not seen in AR−/− mice. (B) Western blot analyze the AR expression in the AR−/− mice. (C) Immunofluorescence analyze the AR expression in the spinal cord of AR−/− mice at 3 day following BPRA injury.Additional file 2. Raw data of western blot.


Supported by international partners, Ukraine is building on rehabilitation work initiated by the government prior to the current conflict. Fid Thompson reports. Yurii Bondarenko (name changed at his request) became a casualty of the war in Ukraine on 2 September 2022. “I was at the market and suddenly there was this loud explosion,” says the 76-year-old geologist who was until recently a resident of the city of Bakhmut in the Donetsk region.Yurii was thrown to the ground, smashing his right elbow. He managed to get back on his feet and make his way home, but then he passed out on the kitchen floor. “I was lying there for three days,” he says. “My son found me when he came back from a business trip.”When Yurii regained consciousness, he found that he could no longer walk unaided.Yurii is one of thousands of civilians to have sustained injuries in Ukraine since the beginning of the Russian Federation invasion on 24 February 2022. According to the Office of the United Nations High Commissioner for Human Rights (OHCHR), as of 2 October, at least 9132 civilians had been injured and 6114 killed .Most of the casualties have resulted from shelling, missile strikes and aerial bombardment and many of the people injured have required rehabilitation supported by assistive technologies (AT).Ranging from physical devices such as wheelchairs, prostheses, hearing aids and spectacles to digital products such as software and apps that facilitate communication, AT products are as diverse as the needs of the people who require them. In conflict zones, however, the drivers of demand tend to fall into three main categories.“In Ukraine, the bulk of the demand for AT is driven by war-related trauma, the needs arising as people with disabilities flee danger,” explains Tetiana Lomakina, Presidential Adviser on barrier-free society issues, a position established in 2021 as part of a national “Without Barriers” initiative to include and empower people living with disabilities which was launched by First Lady Olena Zelenska.“People are also having to cope with dramatic changes in their living conditions that include the loss of heating, water and electricity, and in many cases the complete destruction of their home,” Lomakina adds.On the trauma side, the rehabilitation needs tend to be urgent and complex. “What we see most commonly are extensive burns and complex fractures caused by explosives,” says Pauline Falipou, an emergency rehabilitation specialist with Humanity & Inclusion , an international nongovernmental organization (NGO) working in Ukraine. “The injuries sustained generally require immediate surgical intervention followed by intensive rehabilitation that has to start as soon as possible and should be followed for months if not years,” she explains.“Rehabilitation was included in the response to the war from day one.”Volodymyr GolykSince March 2022, Humanity & Inclusion has been supporting the rehabilitation and AT needs of injured people in Ukraine’s frontline hospitals, but the NGO also works to address the needs of people living with disabilities in the many communities affected by war, including those living in homes for the elderly and children.The United Nations Children’s Fund (UNICEF) is also heavily committed in Ukraine, monitoring the well-being and safety of some 40 000 children – including children with disabilities – in institutions that have often found themselves caught up in the hostilities, necessitating rapid relocation. “Many of the children are in institutions because of a lack of family support services and inclusive education. Poverty is also a contributing factor,” says Fernando Botelho,  Assistive Technology Program Specialist at UNICEF’s New York headquarters. “So, evacuating and relocating them while ensuring that they can still access education, family support, health and other social services has often been extremely challenging.”The World Health Organization’s engagement in Ukraine includes coordinating the rehabilitation response effort, collaborating with partners to provide on-the-ground training in early (i.e. post-intervention) rehabilitation, and working with the government and partners to establish a national rehabilitation centre for spinal cord injuries.With funding from ATscale, a global, cross-sector partnership launched in 2018 to address gaps in access to AT, WHO has also developed AT kits based on assessments of the rehabilitation needs in the country. The first kit, AT6, comprises six items associated with trauma care – wheelchairs, crutches, walking frames, mobile toilets and shower chairs. Fifty of the kits were delivered with external fixators  to 11 hospitals in Eastern Ukraine in June, enough to support 2500 patients.“The idea is to encourage the integration of rehabilitation services into trauma care,” explains Peter Skelton, Rehabilitation in Emergencies Focal Point at WHO’s Geneva headquarters. “When we send external fixators and bone saws to a trauma hospital, we’re also sending crutches and wheelchairs. So, you’re not just saving or amputating the limb, you’re also thinking about how the person is going to function and access essential services afterwards.”A second-generation kit, AT10, includes items designed to meet the needs of internally displaced people, including static toilets, absorbent products, and three different types of catheter kits. As of 10 October, five such kits had been delivered to hospitals in Eastern Ukraine. UNICEF has developed similar AT packages for children.The delivery of kits is not in itself enough to ensure the delivery of rehabilitation services. As Volodymyr Golyk, technical officer for disability and rehabilitation in WHO’s Ukraine office, puts it: “You can’t just give out crutches or wheelchairs. Properly trained health workers are required to make sure it is put to optimal use as early as possible, starting from the acute rehabilitation phase.”To support health workers engaged in the rehabilitation response, the kits provided by WHO include instructions on how to prescribe, fit and train the recipient of the AT devices. Health workers can also access WHO’s online AT training platform and avail themselves of communication boards that are printed in Ukrainian. As mentioned above, health workers are also receiving on-the-ground training in early rehabilitation.Efforts to boost the rehabilitation capacity of the Ukrainian health system are being greatly facilitated by the system itself, as Golyk is quick to point out. “The emergency rehabilitation response is building on what the Ukrainian government was already developing around assistive technologies and rehabilitation,” he says, noting initiatives that date back to the Russian Federation’s invasion of Crimea and include the training of rehabilitation professionals. “This has meant that rehabilitation was included in the response to the war from day one,” he adds.“Early and comprehensive rehabilitation determines how quickly a patient can return to active life.”Tetiana LomakinaCapacity-building efforts initially focused on the needs of injured military personnel but have since been expanded to boost access for civilians.This drive to increase access reflects a fundamental rethinking of emergency response strategy which emphasizes rapid response and comprehensive support. “The Ukrainian rehabilitation system was formed in a different era and under different conditions,” says Lomakina. “We know now that early and comprehensive rehabilitation determines how quickly a patient can return to active life, become independent, learn, work, and communicate.”It is with a view to providing such care that the President’s office, working in collaboration with the Ministry of Health and the Ministry of Social Policy, is working on setting up inpatient rehabilitation departments with “AT cabinets” (AT units) in 24 hospitals across the country.The units are to be staffed with multidisciplinary teams providing rehabilitation as well as guidance on the use of AT devices, and maintenance and follow-up services. “We now face the task in the middle of war to get the departments set up, train multidisciplinary rehabilitation teams, update legislation and fundamentally change the approach to rehabilitation,” Lomakina says.Lomakina believes that the decentralization of rehabilitation service delivery could be of enormous benefit not only to those injured during the war, but also to the broader population requiring rehabilitation services. To that extent, it is closely aligned with the barrier-free society agenda that was being pursued by the First Lady prior to the invasion.Much of the work required to achieve that agenda has been put on hold because of the war. Notable initiatives include the launch of a Large Construction National Program which emphasizes inclusive infrastructure facilities and public spaces such as a swimming pool accessible to people with disabilities that was built in Zolotonosha and a sports and rehabilitation centre that was being built in Krasyliv.Lomakina is looking forward to getting these and other projects up and running again.For Yurii Bondarenko, walking will be enough. With the support of the Humanity & Inclusion rehabilitation team located in Dnipro, Yurii began his journey back to full autonomy using a balance and mobility trainer. A physiotherapist taught him how to do balancing exercises and he was given an AT device in the form of a walking stick to help him on his way.He and his son have decided to move to the Kyiv region “I have always been very active and getting back on my feet has really raised my morale,” Yurii says. “I am looking forward to going to the market again.”