Annual rainfall trends were partitioned into core wet-season rains (+0.7 mm yr-1), supporting a weak but periodic (5-year cycles) increase in herbaceous mass, and early/late rains (+2.1 mm yr−1), explaining the strongly increased woody foliage mass. Satellite observations confirm these findings for the majority of the Sahel, with total herbaceous/woody foliage mass increases by 6%/20%. We conclude that the rainfall recovery in the Sahel does not benefit herbaceous vegetation to the same extent as woody vegetation, presumably favoured by increased early/late rains.Dryland ecosystems comprise a balance between woody and herbaceous vegetation. Climate change impacts rainfall timing, which may alter the respective contributions of woody and herbaceous plants on the total vegetation production. Here, we apply 30 years of field-measured woody foliage and herbaceous mass from Senegal and document a faster increase in woody foliage mass (+17 kg ha Martin Brandt et al. studied foliage mass from Senegal over 30 years, observing the effects of climate change on dryland vegetation. Rainfall caused increases in both herbaceous and woody foliage, but woody vegetation benefits from rainfall timing changes with potential knock-on effects to the local herbivore populations. Although changes in rainfall, fire regimes, elevated temperatures, atmospheric CO2 and nitrogen depositions are suggested explanations6, only few studies provide quantitative evidence on both the biophysical processes  and controlling factors of long-term dryland vegetation trends7. While Earth observation data have been used extensively to document the spatial and temporal dynamics of vegetation production since the early 1980s8, satellite observed vegetation dynamics in drylands have rarely been separated into their herbaceous and woody components and validated against field observations10.Recent Earth observation studies find a greening of the Earth and in particular in global drylands, which is commonly interpreted as a global increase in net primary production and has been attributed to climate change12. Annual rainfall was identified as the major control increasing annual primary production after prolonged droughts in the 1970s and 1980s13. However, recent studies show an increased frequency of heavy rainfall events14 and a changed seasonal distribution of rainfall15 in the Sahel, which may benefit differently the woody and herbaceous components of the vegetation cover. Several experimental field studies in drylands found that woody vegetation benefits from extreme rainfall events17, and also rainfall falling outside the core of the wet season (early and late rains) is hypothesised to benefit primarily perennial vegetation, which includes woody plants. Herbaceous vegetation in the Sahel are predominantly annual plants wilting towards the end of the rainy season independent of late rains. Yet, the limited availability of continuous long-term field observations of vegetation growth and the failure of satellite systems to readily distinguish between woody and herbaceous vegetation components impedes analysing the link between the dynamics in woody/herbaceous plants and the temporal changes in seasonal rainfall distributions.The Sahel dryland was one of the first areas where greening trends were observed12, yet a few long-term field assessments on vegetation production confirm the general dynamics and trends, including the Gourma region in Mali18, Fakara in Niger19 and the rangelands of Senegal21. In particular, the arid and semi-arid Ferlo region in northern Senegal has been a testing ground for the use of time series of satellite images since the late 1970s: Field measurements on herbaceous mass were used to evaluate vegetation proxies from NOAA AVHRR satellite data, constituting a pioneer work and creating the backbone of modern research on dryland vegetation monitoring23. In 1987, the Centre de Suivi Ecologique implemented a routine collection of ecological field data in Senegal, which nowadays represents one of the rare systematic ground surveys using a consistent methodology over more than three decades and measuring both woody and herbaceous vegetation properties. The length of the transects (1 km) forming the surveys was designed for comparisons with Earth observation data and provides robust estimates at a comparable resolution to the dense time series of low-to-medium resolution satellite sensors23.The general concept of the so-called ‘greening Sahel’ was based on Earth observation dataA combination of Earth observation and field data are used here to analyse the contributions of herbaceous and woody plants on long-time vegetation trends, and the impact of specific temporal rainfall distributions on herbaceous and woody plant trends. The convergence of evidence obtained from the combination of field and remotely sensed data highlights the validity of both datasets, as well as the spatio-temporal patterns emerging from them. Furthermore, strong relationships between field and satellite data justify extrapolation of findings from the field plots to larger areas.Results show that different satellite datasets reliably reflect field-measured dynamics and long-term trends in vegetation production. Whereas optical datasets have difficulties in separating woody and herbaceous vegetation components, vegetation optical depth from passive microwaves is able to assess woody and herbaceous dynamics separately. We find Sahel-wide increases in both herbaceous mass and woody foliage over 30 years, however, woody foliage increases faster than herbaceous mass. This is related to a shift in the timing of rainfall, which benefits primarily woody vegetation. Finally, we find a periodic pattern in the herbaceous production, following a 5-year cycle.27. To reflect the growing season when the annual vegetation mass accumulation is close to its peak , as well as AGH trends and dynamics, remarkably well (r = 0.69–0.87) with root mean square errors (for WPF + AGH) ranging from 160 kg ha−1 (MODIS), 178 (GEOV2), to 215 kg ha−1 (GIMMS3g) for optical sensors, and 182 and 170 for high- and low-frequency vegetation optical depth (VOD and L-VOD), respectively.We first compared a variety of different Earth observation datasets against field observations on green vegetation mass, consisting of annually collected 1987–2016) above-ground herbaceous mass (AGH) and woody plant foliage mass (WPF) from nine field sites  and optical datasets  were substantial, and the widely used GIMMS3g (r = 0.04) was shown to be unsuited to reflect WPF dynamics and is thus not further used in the following sections.The 30th percentile (p30) of the intra-annual time series was used to represent dry season values estimating WPF Fig. . Here, p−1) . However, large inter-annual variations make a linear trend estimate on herbaceous mass largely dependent on the selection of the start and end years of the time series, which is not the case for woody foliage  to the total vegetation mass at the field sites was 71% (±13 SD over the nine sites for 1987–2016) Fig. . However−1) Fig. , which mAlthough the general pattern seen in Fig. 24, we decomposed the annual rainfall (from 1st May to 31st October excluding the core dry season) into rainfallC that is uninterrupted core wet season rainfall, and rainfallEL, which is early and late rains falling before and after the rainfallC period . On average across the nine field sites and 30 years, the core wet season lasts from day of year 204 to 244. Over the 30-year study period, rainfall during the average core wet season remained rather stable, while rainfall both before and after this period increased , confirming the annual rainfall amount as the major driver of annual vegetation production but also leaving room for other explanatory variables  , which was not the case for WPF . Annually decomposed rainfallC showed a stronger relationship with AGH as compared with annual rainfall  . Indeed, the only rainfall variable showing a significant correlation with WPF was the annually decomposed rainfallEL , which was unrelated to AGH .Since annual herbaceous plant growth is primarily sensitive to rainfall during the core wet seasoniod Fig. . The decsed Fig. . Annual c.) Fig. . AGH was04) Fig.  but was −1; 1987–2016) was less pronounced in rainfallC (+0.7 mm yr−1), whereas rainfallEL increased by +2.1 mm yr−1 . The standardized trend seen in rainfallC is comparable to the standardized trend in AGH  and in VOD (P = 0.003), with a ~5-year cycle length following the 1st sinusoidal term. This periodic pattern was less clear in annual rainfall (P = 0.08) but was found to be significant for rainfallC (P = 0.03) and not signifcant for rainfallEL (P = 0.09). The periodic 5-year cycle was also not present in the field-measured WPF (P = 0.7).Although the general long-term changes in AGH and WPF follow a linear trend, the overall significance of AGH trends is low and the deviations from a linear increase appear to follow a dominating periodicity Fig. . To testBased on the strong linear correlation between VOD metrics and both AGH and WPF field data from the Ferlo, we used VOD to test whether the three major patterns observed at the field site level apply also for the western and central Sahel : first, the stronger increase in WPF as compared with AGH, second, stronger increase in early/late rain as compared with core wet-season rain, and third, the periodic cycles in AGH superimposing the long-term positive trend.−1 yr−1 and WPF increased by +9 ± 8 kg ha−1 yr−1. For the entire western and central Sahel area, the summed AGH increased by 0.0025 Pg yr−1 over the 21-year period, and WPF by 0.004 Pg yr−1. Total AGH (WPF) was 0.28 Pg (0.16 Pg) in 1992 and 0.31 Pg (0.24 Pg) in 2012, which is a relative increase of 6% for AGH and 20% for WPF. The share of VOD estimated WPF  increased from 35% in 1992 to 43% in 2012, which is comparable to the percentage numbers observed from the Ferlo field samples. Areas with a significant (P < 0.05) increase in AGH cover a smaller region  than areas with a significant increase in WPF  with decreases in vegetation production being mostly not significant  increases in AGH were mostly located in the Ferlo  and the northern Sahel of Mali, which is in line with field observations shown in ref. 11. Areas with a significant increase in WPF are observed across the entire Sahel; notably in Senegal, Chad, eastern Niger and large parts of Mali. Inter-annual variations were lower for WPF (SD 60 kg ha−1) than for AGH (SD 137 kg ha−1). Decreases in both AGH and WPF were observed in western Niger and around Lake Chad, with no obvious relationship with rainfall, pointing towards other, rainfall independent causes (for example land management).Firstly, we analysed long-term herbaceous and woody vegetation dynamics Fig. , Fig. 6aant Fig. . SignifiC increases by +0.9 mm yr−1 and rainfallEL by +1.4 mm yr−1  impacting on the trend3. An advantage of VOD data over optical satellite systems is the ability to overcome the shortcoming related to the weak signal of woody plants in areas with a woody cover below 10%, where optical satellite images are prone to noise and soil reflectances impacted by straw and litter26. L-VOD data, on the other hand, showed an excellent agreement with field-measured WPF, even though data from the low-frequency sensor were only available for an 8-year period. Our results show the importance of L-VOD data for monitoring vegetation biomass in a semi-arid monsoonal ecosystem, as it is operational at an almost daily basis and insensitive to contamination by clouds and atmospheric perturbations, enabling a regional scale assessment of available vegetation mass already during the cloud-prone rainy season. Moreover, whereas the assessment of herbaceous mass by satellite data has long been established at a high quality29, the possibility to directly assess woody foliage mass is a milestone in dryland research.Using field and satellite data, we were further able to disentangle the trend and dynamics in herbaceous and woody plant foliage mass components. Here, passive microwave systems confirmed the convincing results from earlier studies using VOD to estimate woody cover dynamics27. Moreover, annual herbaceous plants are vulnerable to dry spells, given their shallow rooting depth30. Contrastingly, woody plants are able to make use of early and late rains17, mostly explaining the rapid increase in woody foliage mass under the tendency of Sahelian rainfall increases shifting to the early and late season. These findings are critical and would imply that the traditionally strong linkage between annual rainfall and growing season net primary production could be weakened32. Moreover, recent findings showing an intensification of Sahelian rainfall13, including an increased frequency of large rainfall events33, likely contribute to the observed phenomenon. Indeed, large rainfall events are only partially used by annual plant due to rainfall runoff/on, and thus woody vegetation, which is often spatially concentrated in depressions18, will prosper from more water redistribution after large rainfall events.We found increases in both herbaceous and woody foliage mass during the period of analysis; however, woody foliage mass increased faster than herbaceous mass. These trends were found to be closely related to changes in the seasonal distribution of rainfall as derived from daily satellite-based rainfall estimates. The increase in Sahelian annual rainfall was more driven by early and late rains that are less utilised by annual herbaceous plants, explaining the moderate increase in herbaceous mass. Annual herbaceous vegetation needs a period of concentrated rainfall (core wet season) to germinate, tiller, head, flower and set seeds, and they wilt towards the end of the wet season, independent of late rains (photoperiodicity)P < 0.05) for core wet-season rainfall. The potential mechanisms behind this recurrent cycle of years with high and low herbaceous vegetation production and core wet-season rainfall were not further explored in this study. However, it indicates a relation to the forcing from sea surface temperature (SST) anomalies on vegetation growth in the Sahel via the SST impact on rainfall34. The reasons for the large inter-annual and decadal fluctuations in rainfall are still not entirely understood, but a study by Sheen et al. 35 predicted wet season rainfall variability at both multi-year and inter-annual time-scale driven by the interplay between north Atlantic and Mediterranean SSTs (associated with multi-year (<5 year) cycles) and the El Nino-Southern Oscillation (ENSO) . These driving mechanisms help explaining the periodicity we observed in herbaceous vegetation growth, which is largely controlled by rainfall31.The observed trends in herbaceous mass was, however, not linear, and follow a periodic pattern rather than a linear trend, with a recurrent cycle of ~5 years. This pattern is also found in the satellite data and follows a sinusoidal term, which was less pronounced in the total annual rainfall, but significant (P > 0.05)—or slightly positive—further eastward. If an increase in occurrence of heavy rainfall as well as early and late rainfall events continue in the Sahel, a likely consequence will be that woody vegetation will benefit, involving an increase in woody cover in low-lying run-on areas, as already observed in parts of northern Burkina Faso36. Finally, our study did not explore drivers other than rainfall, and it is possible that elevated atmospheric CO239 and a declining fire frequency8 play a role in the increased woody foliage production. Another possible driver is grazing pressure38, however, for the Sahel, there is no clear relationship between grazing pressure and woody vegetation cover40.The CMIP5 modelling experiment, reported in IPCC AR5, represents the main source of information on expected future climate trends for the Sahel. However, differences between rainfall projections of the models included are large, while an increase in atmospheric greenhouse gases and temperature is certain. There are indications that westernmost Sahel may experience a reduction in rainfall, while trends are insignificant  over grazers (sheep and cattle).26, in contrast to observations from Southern Africa39, where a massive encroachment of thorny woody plants represents a problem for exploitation of ecosystem services for livestock farmers38. Indeed, an increase in production does not necessarily coincide with an expansion in plant density, and does also not exclude the replacement of trees by shrubs42. Although very high spatial resolution imagery gave evidence on an increased density of trees at some places in recent years, and also field data starting in 2000 showed a considerable increase in woody cover  and increasing leaf production of woody plants (WPF) implies that the recovery of rainfall after the Sahel droughts only partly benefits herbaceous plants being the prime fodder resource of the Sahel. It has yet to be tested how these findings relate to greening trends and altered rainfall conditions in global drylands.Yet, it remains a challenge to directly relate the increase in woody foliage mass production with woody plant density and the percentage coverage. Actual changes in percentage of woody cover (number of woody plants and canopy size) are generally subtle in the SahelC) on the one hand, and early and late rains  on the other hand. These rainfall metrics were analysed together with vegetation production measurements.This study aimed at deriving simple and reproducible metrics of vegetation composition (herbaceous and woody) and rainfall from satellite data to use these to establish relationships with field-measured vegetation production, separated in woody plant foliage mass (WPF) and above-ground herbaceous mass (AGH), and to study inter-annual dynamics in woody and herbaceous production and rainfall over three decades. Field data were obtained for the Ferlo in northern Senegal  and WPF (kg ha−1). The methods are described in detail in refs. 29. The nine field sites are representative for the sandy Ferlo, a pastoral region with sandy soils in northern Senegal with a mean annual rainfall of 328 mm (from 1982 to 2016). Woody vegetation is generally scattered and the crown cover fraction is below 10% (with a mean WPF of 362 kg ha−1), but trees can be concentrated and woody cover reaches 40% in more loamy inter-dune depressions43. Herbaceous vegetation consists of annual plants (mean AGH = 939 kg ha−1) which wilt towards the end of the rainy season turning into straw and litter27. The mass of straws and litter decreases progressively during the dry season due to livestock grazing and trampling, insect herbivory and organic decomposition. The sum of AGH and WPF reflects the total green vegetation mass. The homogeneous landscapes of the Ferlo  make it well-suited for establishing relationships with medium to coarse resolution satellite data44.Field data was obtained from the Centre de Suivi Ecologique database and included annual measurements of nine field sites from the sandy Ferlo in northern Senegal, each covering a 1 km transect and located in rangelands selected to be distant from livestock concentration spots. At each site, two components were measured annually from 1987 to 2016: AGH , SPOT VGT and PROBA-V  and MODIS  and VOD indices derived from passive microwave satellite systems. One VOD index used here is based on recordings in the high wavelength frequency domain  and another is based on SMOS observations; the first passive microwave radiometer operating at a low frequency . Two of the time series can be considered as long-term (GIMMS3g and VOD), whereas the remaining datasets only start in 1999 or later. Apart from SMOS L-VOD, we selected satellite datasets that were already pre-processed, including the selection of the best-quality observations, cloud filtering, gap filling and temporal smoothing. Also, adjustments to the use of varying sensors had already been performed and we refer to the respective product guides for further information48. For L-VOD, we used the SMOS-IC version and filtered out low-quality observations following49 and aggregated daily images to 10-day medians which were further filtered with a local weighted regression . The temporal resolution of the datasets ranged from 10 days , 15 days (GIMMS3g) to 1 month .Satellite time-series data covering several decades are becoming increasingly available and new generations of data processing technologies have considerably improved vegetation monitoring by offering independent and complementary information. Satellite data applied in this study can be grouped into optical indices derived from AVHRR sensors  which is the annual amount of rainfall that can be utilised by annual herbaceous plants, including rainfed crops. It corresponds to a temporal window during the wet season which is not interrupted by dry spells. RainfallEL (early and late rains), which is the annual amount of rainfall falling between 1st May and 31st October and before or after the core wet-season rains  are established: CR-5 accumulates daily rainfall subtracting 5 mm each day (when available), CR-3 accumulates daily rainfall subtracting 3 mm each day (when available). CR-5 and CR-3 cannot be negative .C) from early and late rains :Four dates are to be established to separate core wet-season rains , or first day with CR-5 positive after the last dry spell, but before 15th August. End of core wet season: After 15th August, and before possible dry spells, i.e. if a dry spell occurs between 15th August and the last rain, the core wet season ends. Last rain: After 15th August, the last day with rainfall above 12 mm or five consecutive days with a sum of >20 mm.Dry spells are identified if any of the following conditions are true:Six consecutive days where CR-3 is zero. Twelve consecutive days with summed CR-3 balance below 6 mm. Eighteen consecutive days with summed CR3 balance below 9 mm. Twenty-four consecutive days with summed CR3 balance below 12 mm. Thirty consecutive days with summed CR3 balance below 15 mm.C, and subtracted from the annual rainfall (that is from 1st May to 31st October) to derive rainfallEL. The average starting date of rainfallC was day of year 204 and the average ending date was day of year 244. These two dates were used to establish the core wet season for the analysis at Sahel scale, without considering the latitudinal rainfall gradient. Using these two approaches of various complexities  also gives evidence on the robustness and replicability of the results.If two or more of the conditions apply, the longest dry spell prevails. The dates were identified for the CHIRPS pixels overlaying the nine field sites and the start and ending date of the core wet season were derived for each year and site (1987–2016). The rainfall summed over this period was termed rainfall51. Nevertheless, the establishment of a clear statistical relationship between rainfall and plant growth is difficult, since runoff/run-on, topography, herbivores, species composition and soil fertility are factors impacting on the relationship but are not taken into account in this study.From literature, perennial plants (including woody vegetation) are not limited to a strict rainfall pattern52, which varied from 1 km , 5.6 km (MODIS), 8 km (GIMMS3g) to 25 km (VOD and L-VOD). Due to the varying spatial resolutions, it cannot be avoided that different spatial areas are inter-correlated, but this does not affect the temporal dynamics52. The application of p30 does not fit the characteristics of the SMOS sensor , so instead we applied p10 in the case of SMOS to capture the low values of the dry season (p30 of SMOS would be located in the wet season).To study inter-annual dynamics in vegetation production with both satellite and field data, we used the nine field sites and averaged p90 and p30 of each satellite data set for each year overlaying the sites. It is expected that using an average over several sites reduces noise introduced by the different spatial resolution of the datasets26.To estimate annual vegetation production with satellite data, the coefficients of a linear regression between annual satellite metrics and field data (average of 9 sites) were applied to the annual satellite imagery. P90 (reflecting the growing season) was used to estimate the total vegetation mass, and p30 (reflecting the dry season) for the WPF. The availability of in situ observations that separate AGH and WPF provide an opportunity to assess the validity of satellite-derived WPF dynamics. Derivation of WPF from satellite data is based on the contrasting phenology of woody and herbaceous vegetation, with annual herbaceous plants wilting at the end of the wet season while woody plants keep their green foliage during a fraction of the dry season. Dry season satellite imagery can thus be used to capture the WPF component separately from the AGH component23. The calibration between satellite and field data was done over the Senegalese Ferlo, and the coefficients were subsequently applied over the entire West African Sahel. This is deemed appropriate as the entire Sahel zone shares similar conditions: a monsoonal climate with rainfall only from June to October, predominant pastoral use, scattered woody vegetation with an average coverage of 3%  and 9%  dominated by evergreen species42, and annual herbaceous vegetation. Since our analysis does not exceed 600 mm annual rainfall, perennial herbaceous plants are not common.Assuming that WPF is present at both dry and wet season whereas AGH is only present during the wet season, AGH was estimated by subtracting WPF (estimated by p30) from AGH + WPF (estimated by p90). Equations Further information on experimental design is available in the Reporting SummarySupplementary informationDescription of additional supplementary itemsSupplementary Data


Human T-cell leukemia virus type 1 (HTLV-1), the first reported human oncogenic retrovirus, is the etiologic agent of highly aggressive, currently incurable diseases such as adult T-cell leukemia–lymphoma (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HTLV-1 proteins, including Tax and HBZ, have been shown to have critical roles in HTLV-1 pathogenicity, yet the underlying mechanisms of HTLV-1-driven leukemogenesis are unclear. The frequent disruption of genetic and epigenetic gene regulation in various types of malignancy, including ATL, is evident. In this review, we illustrate a focused range of topics about the establishment of HTLV-1 memory: (1) genetic lesion in the Tax interactome pathway, (2) gene regulatory loop/switch, (3) disordered chromatin regulation, (4) epigenetic lock by the modulation of epigenetic factors, (5) the loss of gene fine-tuner microRNA, and (6) the alteration of chromatin regulation by HTLV-1 integration. We discuss the persistent influence of Tax-dependent epigenetic changes even after the disappearance of HTLV-1 gene expression due to the viral escape from the immune system, which is a remaining challenge in HTLV-1 research. The summarized evidence and conceptualized description may provide a better understanding of HTLV-1-mediated cellular transformation and the potential therapeutic strategies to combat HTLV-1-associated diseases. Human T-cell leukemia virus type 1 (HTLV-1) infection  is assocHBZ in CD4+ T-cells also induces T-cell lymphomas and systemic inflammation in mice . Although Tax has already disappeared at the time of ATL onset, Tax and its interactome (described in later chapters) have already left multiple genetic and epigenetic memories, contributing ATL onset. This switch during leukemogenesis is indeed supported by transcriptome data; the changes in gene expression in infected cells are dominated by disordered homeostasis and the characteristics of ATL.However, leukemic cells possess similar traits as Tax-expressing cells . AlthougAlthough cancer is typically considered to be a genetic disease, chromatin and epigenetic aberrations as well as active roles of HBZ play important roles in tumor potentiation, initiation, and progression in ATL and HTLV-1-associated diseases. Based on recent findings, we introduce a hypothesis with important implications that might explain the underlying mechanism of the issue: the molecular memories inherited from HTLV-1.Cellular characteristics  are strictly defined by the regulation of gene expression. HTLV-1 Tax directly affects host gene expression through multiple mechanisms, including the binding with host transcription factors and the perturbation of multiple signaling pathways . IntriguCDKN2A (p16INK4A), via physical interaction  inhibitor, eraction . The miteraction .Comprehensive gene expression profiling revealed that several positive regulators of the cell cycle process are overexpressed in acute-type ATL, in most of which HTLV-1 sense-transcripts and the virus replication is silenced. Diverse abnormalities were also found in each of these comprehensive studies; however, several gene alterations and other critical events have been commonly implicated as the determinants of gene expression pattern. The abnormalities in the expression of different cytokines, their receptors, and various proteins that act as anti-apoptotic factors or proliferating agents are the cellular hallmarks responsible for malignant phenotypes . These nGenetic, metabolic, and environmental stimuli can induce overly restrictive or permissive epigenetic landscapes that contribute to the pathogenesis of cancer and other diseases. The restrictive chromatin states prevent the appropriate expression of tumor suppressors or block differentiation. In contrast, the permissive states allow the stochastic activation of oncogenic genes and stochastic silencing of tumor suppressor genes. The abnormal restriction or plasticity may also affect other processes mediated through factors such as chromatin–DNA repair and telomere maintenance.Chromatin homeostasis, a basis of molecular memory , is disrTax directly participates in genetic damage . In paraThe recent advanced technology-based comprehensive characterization of genetic abnormalities delineated the spectrum of genetic alterations in ATL . GenomicDepending on the cellular status, a transient cue such as an inflammatory cytokine can induce stable malignant transformation through a positive feedback network that is normally held in check by a host defense mechanism . In thisTax can activate several signaling pathways and lead to an abnormal gene expression pattern. For instance, it can activate NF-κB and NFAT pathways responsible for the predominant expression of IL-2 and its receptor IL2R , whose aNegative regulators within the network are critical for the homeostasis of the regulatory motif. In the developmental process of HTLV-1-infected cells, some NF-κB negative regulators are diminished or inactivated, leading to chronic activation of the signaling pathway. For example, miR-31, a new class of negative regulator of the non-canonical NF-κB pathway, acts by regulating NIK. One mechanism of NF-κB activation without Tax is the epigenetic silencing of miR-31 in HTLV-1-infected cells and aggressive ATL cells .Another NF-κB negative regulator, p47, which is essential for Golgi membrane fusion, associates with the NEMO subunit of IκB kinase (IKK) complex upon TNF-α or IL-1 stimulation and inhibits IKK activation. Tax inhibits the interaction between p47 and the IKK complex. In contrast, a significant reduction of p47 expression has been reported in ATL cells, which show a high-level constitutive NF-κB activation that protects ATL cells from apoptosis in a Tax-independent manner . These fChromatin is the fundamental medium through which transcription factors, signaling pathways, and various other cues influence gene activity. A dynamic change of the chromatin conformation reinforces regulatory activity or repression at each locus and causes reorganization in response to appropriate intrinsic and extrinsic stimuli.Genes encoding epigenetic factors, including SWI/SNF complex members and DNA methylation modifiers, are among the most frequently mutated genes in human cancers . HoweverTET2, IDH2, and DNMT3A. Additionally, C2H2-type zinc finger genes (implicated in the suppression of endogenous and exogenous retroviruses) were hypermethylated and silenced. Furthermore, the hypermethylation of MHC-I expression may contribute to immune evasion.The ATL is also characterized by prominent CpG island DNA hypermethylation, leading to transcriptional silencing . ApproxiWhen we consider the chromatin aberrations that confer plasticity, the polycomb family and its substrate histone, H3K27, are of particular interest. EZH2 can repress a wide range of genes by catalyzing the trimethylation of H3K27 (H3K27me3). Regarding the cellular function, EZH2 and H3K27me3 act in a highly context-dependent manner. EZH2 gain-of-function mutations may be oncogenic in a B-cell lineage . In addiWe recently analyzed the pattern of ATL histone modification and integrated it with the transcriptome from primary ATL cells to decipher the ATL-specific “epigenetic code” . PRC2-meImportantly, the Tax-dependent immortalized cells also show significantly similar H3K27me3 reprogramming as that of ATL cells. A majority of the epigenetic silencing occurs in leukemic cells from indolent ATL and in HTLV-1-infected premalignant T-cells from asymptomatic HTLV-1 carriers.The important implications for deciphering the triggers of the specific histone code are physical interaction and other influences on the host epigenetic machinery by Tax, including the key histone modifiers HDAC1 , SUV39H1KDM6B, encoding a JMJD3 demethylase of H3K27me3, is significantly downregulated upon H3K27me3 gain .Therefore, as a hypothesis, we propose, in agreement with the established developmental pathway of HTLV-1-infected cells, that disease progression fits with the epigenetic landscape, wherein the height of the walls between the canals is determined by several molecular events . During a long period, several aberrant characteristics are acquired and fixed, nevertheless Tax disappears. The consequent genotype and epigenotype support the differential phenotypes and the disease entities of ATL and HAM/TSP.HTLV-1 provirus is frequently defective or silenced in ATL. However, the lesions recurrently detected in ATL cells imitate the function of Tax and would be stably inherited in the progeny of the malignant cells. This raises several critical possibilities such as that the active imprinting of the viral function into the host genome and epigenome is one of the critical steps of leukemogenesis. Furthermore, the features of ATL cells are not accidental but are the products of HTLV-1 infection. In addition to the sustained roles of HBZ  is an urgent requirement. Therefore, there is a need to investigate the abnormalities contributing to the molecular pathogenesis, including those in master transcription factors and chromatin regulators. Furthermore, in addition to cellular traits, environmental parameters such as aging, cellular stress, and immune response should be integrated into our model of this process. The order of the molecular events is just a pathway of disease development. HTLV-1 infection and following epigenetic reprogramming may be an initial step of fate changes.At present, researchers and hematologists are sharing their findings on the characteristics of ATL cells. Additionally, the phenotypic characteristics of HAM/TSP have been studied. Considering the therapeutics for the HTLV-1-associated diseases and the need to eliminate the premalignant cell population, the establishment of a precise understanding of disease developmental pathways . Realizing the potential of such mechanism-based medicines and advanced diagnostic tools for the detection and evaluation of tumor stage and heterogeneity will require a deeper understanding of epigenetic plasticity and restriction. The road ahead is long but must be challenged to capture this major component of HTLV-1 biology and its associated diseases.Intentional regulation such as by inhibitor treatment will reprogram the fate of HTLV-1-infected cells, which can be conceptualized as a reduction or elevation of the walls between the canals in the epigenetic landscape, in line with the analogy mentioned above (MY conceived and supervised the project, summarized and conceptualized the evidence, and wrote the paper. DF, TW, and KU discussed the new concept.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.


Chromosomal translocations involving the BCR and ABL genes result in the creation of the BCR-ABL oncogene that displays constitutive tyrosine kinase activity resulting in aberrant signaling leading to hematopoietic stem/progenitor cell transformation and leukemia. Recently, our laboratory reported a quantitative proteomics examination of signaling differences between the two main BCR-ABL variants, p190 and p210, which are associated with distinct leukemias in humans [Ubash3b, also known as suppressor of T-cell receptor signaling or Sts-1, is an ill-studied atypical tyrosine phosphatase with ubiquitin binding ability . Taken tWe previously described a system to analyze the signaling pathways of p210 by stable expression of BirA* tagged p210 BCR-ABL in Ba/F3 cells  upon Ubash3b KD , which has been shown to be required for BCR-ABL mediated transformation . Ubash3bA number of essential BCR-ABL adapter proteins were also differentially phosphorylated upon Ubash3b KD, including Dok1, CrkL, Grb2, Gab2, Pik3ap, and CD2ap (Supplementary Table Another molecule particularly important for BCR-ABL signaling found to be hyperphosphorylated and decreased in interaction with p210 upon Ubash3b KD was STAT5 (Supplementary Fig. To date, the interactome of Ubash3b has not been extensively investigated; however, limited investigation of Ubash3b in the context p210 signaling has been undertaken . UnderstIn summary, this study represents a novel multi-proteomic approach to dissect the role of Ubash3b in p210 BCR-ABL signaling. Ubash3b displays strong negative regulatory role exhibited by dephosphorylation of p210 and p210 signaling molecules in addition to its effects on proteins that interact with p210 Fig. . These dSupplementary Figure LegendsSupplemental MethodsSupplementary Figure 1Supplementary Figure 2Supplementary Tables 1-5


Leptin is an important secretory protein that regulates the body’s intake and energy consumption, and the functions of the Hh signaling pathway related to white adipocyte browning are controversial. It has been reported that leptin plays a critical role in adipogenesis by regulating the Hh signaling pathway, but whether there is a functional relationship between leptin, the Hh signaling pathway, and adipocyte browning is not clear. In this research, mouse white pre-adipocytes were isolated to explore the influence of the Hh signal pathway and leptin during the process described above. This showed that leptin decreased high fat diet-induced obese mice body weight and inhibited the Hh signaling pathway, which suggested that leptin and the Hh signaling pathway have an important role in obesity. After activation of the Hh signaling pathway, significantly decreased browning fat-relative gene expression levels were recorded, whereas inhibition of the Hh signaling pathway significantly up-regulated the expression of these genes. Similarly, leptin also up-regulated the expression of these genes, and increased mitochondrial DNA content, but decreased the expression of Gli, the key transcription factors of the Hh signaling pathway. In short, the results show that leptin promotes white adipocyte browning through inhibiting the Hh signaling pathway. Overall, these results demonstrate that leptin serves as a potential intervention to decrease obesity by inhibiting the Hh signaling pathway. Adipose tissue plays an important role in maintaining the body’s energy balance. Adipose tissue is an important endocrine organ; it participates in the activities of the body for physiological regulation by secreting a variety of adipose cytokines . AdipocyDrosophila by Nusslein-Volhard and Wieschaus [Drosophila embryos becoming spiny, small, and globular, like a hedgehog, and thus this mutation is called “Hedgehog” [Hh protein, a “segment polarity” gene, was first discovered in ieschaus . Hh mutaedgehog” . The Hh edgehog” , and theedgehog” . Researcedgehog” ,14, withedgehog” ,16,17. Fedgehog” . TherefoLeptin is a secretory protein of adipose tissue that is widely found in mammals, amphibians, reptiles, and fish. Its genetic sequence is highly conserved. It enters the brain through the blood–brain barrier, and inhibits the expression of POMC and NPY/AgRP in the hypothalamic arcuate nucleus (ARC), which suppresses appetite in the brain ,20,21 anTo explore the effect of the Hh signaling pathway in the process of adipocyte browning, and the relationship between the leptin/Hh signaling pathway and adipocyte browning, two compounds were used to inhibit or activate the Hh pathway, respectively. Cyclopamine (Cy), a plant-derived teratogen , inhibitThree-week-old C57BL/6 male mice were purchased from the Medical Laboratory Animal Center of Xi’an Jiaotong University . The animal experiments were developed with reference to the Guide for the Care and Use of Laboratory Animals of China.To determine the role of leptin in vivo, leptin recombinant protein was injected into high fat diet (HFD) induced obesity mice. Briefly, the 3-week-old male C57BL/6J mice, after 8 weeks of an HFD , were injected with leptin recombinant protein (R&D system) or phosphate buffered saline (2.5 mg/kg) into the intraperitoneal. The injections were performed for seven days, twice a day. The mice were housed in a 12:12 h light/dark cycle with free access to water and food.Immediately after sampling, the adipose tissue was fixed with 4% paraformaldehyde. After this, the samples were dehydrated and embedded in paraffin. Sections were cut using a Nikon TE2000 microscope  and standard HE staining was performed.The serum leptin concentration was measured by means of a commercial canine leptin sandwich ELISA kit , according to the manufacturer’s instructions. The absorbance of each well at 450 nm was measured with a microplate reader .3 pieces. Type I collagenase was digested for 40–50 min with oscillation of water at 37 °C. The same volume of Dulbecco’s modified Eagle’s medium/Nutrient Mixture F12 (DMEM/F12) medium with 10% fetal bovine serum  was added to terminate digestion, then the solution was sieved through 70 and 200 mesh screens after being collected in a 10 mL tube, undergoing 1800 rpm centrifugation for 7 min, abandoning the supernatant, adding the DMEM/F12 serum-free medium rinse again, 1500 rpm centrifugation for 5 min, and culturing in DMEM/F12 serum medium at 37 °C in a humidified atmosphere with 5% CO2. After 24 h, it was washed twice using PBS and the DMEM/F12 serum medium was replaced. After that, the culture medium was changed every two days. Confluent pre-adipocytes were subjected to brown adipocyte differentiation medium I . The cells were switched to brown adipocyte differentiation medium II  after two days. Then, the culture medium was changed every other day and collected at different time points. A 10 µmol/L concentration of activators or inhibitors, or a 100 nmol/L concentration of leptin recombinant, was added each time the brown adipocyte differentiation medium was changed. However, the activator and leptin treatment was different compared with the activator or leptin alone. In this step, a 10 µmol/L concentration of activators and 100 nmol/L concentration of leptin were added into differentiation medium II. All the liquids were combined with 100 IU/mL penicillin–streptomycin.The mice were sacrificed, and inguinal white adipose tissue (iWAT) was isolated and washed three times with PBS. The fat pad was cut into approximately 4 mmOil red O was filtered and diluted (3:2) with double distilled water. The cells were washed with PBS three times after dyeing, and fixed in 4% paraformaldehyde for 30 min. After three washes with PBS, oil red O staining was undertaken for 30 min. PBS was used again for washing three times, and finally the picture was taken.Bodipy was diluted with PBS (1:1000) and DAPI was also diluted with PBS (1:1000). The cells were washed with PBS three times after dyeing and fixed in 4% paraformaldehyde for 30 min. After washing with PBS three times, bodipy staining was undertaken for 30 min. Then, it was placed on a horizontal shaker and washed with PBS once every 5 min. After washing three times, DAPI staining was undertaken for 10 min, washing was completed another three times, and finally a picture was taken with a fluorescence microscope .−ΔΔCT method.Total RNA was extracted using the Trizol  method, following the manufacturer’s instructions. mRNA was reverse transcribed with transcription kits  to synthesize cDNA, and the cDNA was performed using SYBR green kits on a Step one plusTM system . The primer sequences for the genes are shown in To determine mitochondrial DNA (mtDNA) content, genomic DNA was extracted using a DNA isolation kit . The mtDNA copy number was calculated from the ratio of the 16s rRNA and a mtDNA to the hexokinase 2 gene. The RT-qPCR primer sequences are shown in The cell total protein was isolated using RIPA , and protease inhibitor  was added into the RIPA at a ratio of 1:100. After adding RIPA to the cell culture plate, we collected the cells, then followed this by centrifuging  at 4 °C for 10 min. Protein concentrations were measured using the Thermo Scientific Pierce BCA protein assay kit , and 1/4 volume of 5× loading buffer was added to the supernatant. A total of 20 µL of protein was blotted using 10% SDS-polyacrylamide gel, and transferred to a polyethylene difluoride (PVDF) membrane . After blocking with 5% defatted milk for 2 h, membranes were incubated with antibodies (1:1000) against Gli1 , Gli2 , Gli3 , PGC1α , PPARγ , UCP1 , aP2 , Cox7a , and β-tubulin  overnight at 4 °C. The membrane HRP goat anti-mouse IgG, goat anti-rabbit IgG, or rabbit anti-goat IgG secondary antibodies  were diluted 1:3000 and incubated for 1 h. Detection was performed using chemiluminescence western blotting substrate , with lmage Lab analysis software .p value < 0.05 was considered statistically significant, and a p value < 0.01 was considered extremely statistically significant. .All data were expressed as means ± SD, and statistical analysis was performed with GraphPad Prism 7.0. Data were analyzed using a Student’s test or one way ANOVA. A As a fat-secreting factor, more and more studies have shown that leptin can regulate the energy metabolism of the body in several different ways . Some stCidea, and many mitochondria-related genes. We next studied the common transcriptomic changes in any two groups and generated enriched KEGG pathways clustered by target genes of the Hh signaling pathway, for exploring its potential roles as a biomarker of browning  ((p < 0.05) (p < 0.05) ((p < 0.05) (Gli1 expression of white adipose. Leptin recombinant protein significantly decreased Gli1 expression in iWAT (p < 0.05) (Gli1 expression levels were increased (p > 0.05) (Previous research has shown that leptin can improve metabolism in ob/ob mice prone to obesity . In orde < 0.05) A,C, and  < 0.05) D,E. Hema < 0.05) F,G. Seru < 0.05) H. RT-qPC < 0.05) I. Howeve > 0.05) I. This pGli1/2/3, the key transcription factors of the Hh signaling pathway, were significantly decreased (p < 0.05 or p < 0.01)  (p < 0.05 or p < 0.01)  A. Howeve < 0.01) B,C. West < 0.01) D,E. Bodi < 0.01) F–H. ThesGli1/2/3 were significantly increased (p < 0.05 or p < 0.01)  (p < 0.05 or p < 0.01)  A. The ex < 0.01) B,C after < 0.01) D,E. The  < 0.01) F–H. The Gli1, the key transcription factor of the Hh signaling pathway. We observed that the mRNA expression of Gli1 reduced in a concentration-dependent manner, with the increase of leptin concentration. However, the expression of Gli1 was increased in cells treated with 200 nmol/L of leptin treatment (p < 0.05) (p < 0.05)   A, and th < 0.05) C. Intere < 0.01) B–D. Thisp < 0.05 or p < 0.01) (p < 0.05 or p < 0.01)   B,C, and  < 0.01) D. Howeve < 0.05) E. The re < 0.05) F,G. LeptLoss of leptin (ob/ob) or the Lep-R mutation (db/db) causes a series of metabolic abnormalities in mice, including obesity, diabetes, and hypercorticoidemia. It can be seen that leptin is essential for maintaining the body energy balance. The Hh signaling pathway plays a vital role in embryogenesis. The Gli transcription factor family plays an important role in the Hh signaling pathway. Gli1 and Gli2 mainly act as transcriptional activators, even though Gli2 has a weak repressing activity. Gli3 mainly functions as a transcriptional repressor ,34,35. TGli1 expression was decreased in iWAT, indicating leptin was related to the Hh signaling pathway.Chen et al found that leptin was not able to treat typical obesity; however, it is effective for reversing leptin deficiency-induced obesity, and was found to be possibly useful in treating lipodystrophy . In ordeZhang et al discovered that Hh signaling regulated PthrP and adiponetic secretion in bone, and PthrP and adiponetic regulated whole body energy metabolism by promoting white adipocyte browning . Farr etGli1, the key transcription factor of the Hh signaling pathway, was decreased with the increase of leptin. This indicates that leptin inhibited the Hh signal pathway. With inhibition of the Hh signaling pathway, the expression of thermogenesis and mitochondrial related genes was increased.In addition, after treatment with different concentrations of leptin recombinant protein, the expression of Gli1 expression was reduced in the mRNA and protein levels. This suggested that the role of leptin was consistent with it inhibiting the Hh signaling pathway. However, Liu et al. found that leptin can activate the Hh signaling pathway in 3T3-L1 cells to inhibit adipocyte differentiation [UCP1 and PGC1α in the mRNA and protein levels. This demonstrates that leptin significantly enhanced white adipocyte browning, which is consistent with Dodd’s results [To illustrate the relationship between leptin and Hh signaling, the cells were treated with leptin. Compared with NC, the lipid droplets were smaller and the number of cells was larger. This showed that leptin reduces the lipid droplet size of adipocytes. Similarly, the same results can be obtained with Cy treatment, so it was speculated that the role of leptin may be consistent with Cy inhibition of the Hh signaling pathway. To confirm this speculation, we tested the expression of Gli1, a key factor of the Hh signaling pathway, and found that leptin inhibited the expression of Gli1. After Pu with leptin treatment compared with only Pu treatment, ntiation . We specntiation . In this results .In summary, in this study, leptin was considered to promote white adipose browning and inhibit the Hh signaling pathway. It was found that activation of the Hh signaling pathway inhibited white adipocyte browning, while its inhibition promoted white adipocyte browning. This study further showed that leptin reversed the effects of Pu on white adipose browning. The above results show that leptin promotes adipocyte browning by inhibiting the Hh signaling pathway . However


There was no improvement in the survival period following γ-irradiation in the γ-irradiated group after HTLV-1 infection when compared with the HTLV-1-infected group. It was also found that the incidence of splenomegaly was ≥80% in the HTLV-1-infected and γ-irradiated group, which was significantly higher than that in the HTLV-1-infected mice. The tissue morphology in the spleen became non-uniform because of γ-rays. Importantly, the number of infected cells in the spleen was increased 4.1-fold in the HTLV-1-infected and γ-irradiated mice compared with that in the HTLV-1-infected mice. Careful consideration might be necessary when using whole-body irradiation in patients with HTLV-1 infection.Adult T-cell leukemia is one of the life-threatening diseases that occur in individuals infected with human T-cell leukemia virus type 1 (HTLV-1). Clinical trials of hematopoietic stem cell transplantation therapy are being performed in addition to chemotherapy; however, neither is satisfactory. As a pretreatment for transplantation, anticancer drugs or whole-body irradiation is used to decrease the number of HTLV-1-infected cells, but there are numerous side effects. Therefore, in the present study, using a mouse model of HTLV-1 infection, the long-term survival and number of infected cells in the reservoir organ were investigated in order to determine the effect of γ-irradiation on HTLV-1-infected mice  Human T-cell leukemia virus type 1 (HTLV-1) exists as a provirus in host cells following infection, and ~5% of HTLV-1 carriers become adult T cell leukemia (ATL) following 50–60 years of persistent infection . A highein vivo [The aim of radiation therapy is to completely destroy the tumor or to reduce tumor size, and it is used as a pretreatment prior to hematopoietic stem cell transplantation for ATL. However, the effect of irradiation on reduction of proviral loads in the reservoir organ is not well characterized. The present study used an HTLV-1-infected mouse model and examined the effects of whole-body γ-irradiation on HTLV-1-infected cells in the reservoir organs in vivo , 5.6 MT-2 cells [137Cs, Nordion International). The dose rate of the γ-irradiation was 0.952 Gy/min. Autopsy was performed when a reduction in body weight of ~30% or on day 260 after birth was observed, and tumors occurring in the thymus and spleen were excised.MT-2 cells, an HTLV-1-infected human T-cell line, were cultured as described . C57BL/6-2 cells , 7. The The spleens of mice were fixed in 10% neutral formalin and embedded in paraffin. The paraffin sections of 5 μm thickness were stained with hematoxylin and eosin and were examined microscopically.DNA from the spleen was extracted by sodium dodecyl sulfate-proteinase K digestion, followed by phenol extraction.tax and mouse c-myc molecules were quantified using real-time PCR, and the HTLV-1 proviral load per 105 mouse cells was calculated as follows: (number of tax molecules/number of mouse c-myc molecules/2) × 105. The proviral load was defined as zero when there was no amplification of the tax product following 50 cycles of PCR under conditions where mouse c-myc was amplified correctly.The polymerase chain reaction (PCR) conditions for quantification of the HTLV-1 proviral load were as described previously . Brieflyt-test was used to detect any difference between the mean scores in two groups, based on the equality test of two variances.Welch’s P = 0.099), and between the γ-irradiated group and the HTLV-1-infected and γ-irradiated group by a log-rank test (P = 0.276)  and splenomegaly was observed in three mice at 4 months in the 12 month observation period; in the HTLV-1-infected and γ-irradiated group, thymoma was observed in 2 out of 15 mice and splenomegaly was significantly observed in 13 out of 15 mice (P < 0.01)  for the English language review.We are indebted to Dr. Junichi Fujisawa  for generous support of the work. We thank Enago . The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.


Ursolic acid (UA) is a pentacyclic triterpene which is found in common herbs and medicinal plants that are reputed for a variety of pharmacological effects. Both as an active principle of these plants and as a nutraceutical ingredient, the pharmacology of UA in the CNS and other organs and systems has been extensively reported in recent years. In this communication, the antioxidant and anti-inflammatory axis of UA's pharmacology is appraised for its therapeutic potential in some common CNS disorders. Classic examples include the traumatic brain injury (TBI), cerebral ischemia, cognition deficit, anxiety, and depression. The pharmacological efficacy for UA is demonstrated through the therapeutic principle of one drug → multitargets → one/many disease(s). Both specific enzymes and receptor targets along with diverse pharmacological effects associated with oxidative stress and inflammatory signalling are scrutinised. The general biosynthetic routes of terpenoids are depicted in Ursolic acid (UA) is a common name for the plant triterpenoid compound, 3One of the nature's wonder in structural diversity of plant secondary metabolites is reflected through the identification of well over 20,000 triterpenes from just a single squalene precursor. In the first instance, glycosylation to give the diverse saponins and related complex structures is the common route of structural diversity. Beyond oxidations to give the hydroxyl and common carboxylic acid derivatives, cyclisation patterns of terpenoids are the major source of structural diversity. For the triterpenes, the pentacyclic skeletons are among the most common and include the oleanane and ursane groups, among others . The difference between oleanane and ursane is based on the migration of one methyl group (C-30) in the latter compound from C-20 to C-19 position. The common derivatives of these two compounds are based on C-3 hydroxylation, C-28 carboxylation, and a double bond at C-12 position to form UA and oleanolic acids while further hydroxylation at C-2 position gives corosolic acid and maslinic acid . These tDespite its common occurrence in nature including in herbs such as basil, rosemary, and sage or common fruits including apple and pears, UA has diverse pharmacological effects. Some of these effects are reviewed in recent years and include brief overviews of pharmacology related to anticancer , 2, antiTraumatic brain injury (TBI) refers to pathological events related to alteration of the brain function as a result of direct damage by external force such as a blunt to the head. The resulting widespread axonal injuries and lesions in various regions of the CNS could lead to symptomatic abnormalities in cognitive and motor functions, behavioral and emotional domains. The most common and long-lasting abnormality associated with TBI however remains to be memory-related cognitive impairment . FollowiThe significance of TBI and, to a lesser extent, spinal cord injury (SCI) has been reviewed in recent years by various authorities. According to the GBD collaborator group study , the gloThe activation and subsequent translocation of the nuclear factor-erythroid 2-related factor 2 (Nrf2) are induced by a variety of stimuli including oxidative stress leading to the transcriptional activation of antioxidant genes such as heme oxygenase-1 (HO-1), GST, NADPH quinone oxidoreductase-1 (NQO-1), and SOD. On the basis that UA exert antioxidative and anti-inflammatory effects on cerebral ischemia by activating the Nrf2 pathway, Ding et al.  evaluateκB (NF-κB) P65, interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS), and matrix metalloproteinase- (MMP-) 9. These anti-inflammatory effects coupled with a reduction in the apoptosis score suggest the neuroprotective effect of the compound [Zhang et al. , 20 emplcompound . On the compound . This inα in the injured spinal cord while activating the mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathways in the injured spinal cord.An interesting insight into the neuroregeneration and regrowth potential of UA has been investigated by Sahu et al.  using thκB after stroke in mice. Since Nrf2−/− mice were more susceptible to neuronal damage (infarct size and oxidative and inflammatory scores) in the MCAO model and UA does not extend its protective effect in this mouse group, the Nrf2 signalling pathway is at the forefront of the potential mechanism of action for UA. Hence, the effect of UA is consistent to the well-known effect of the Nrf2-antioxidant response element signalling pathway in oxidative stress [Perhaps the best pathological disease associated with cerebral ischemia is the cerebrovascular disease (stroke) which results from either disruption of blood supply (ischemia) or haemorrhage. Li et al.  studied e stress , 24 and e stress –28.β, TNF-α, and IL-6), TLR4, and inactivated NF-κB, while the high-mobility group box 1 (HMGB1) was also inhibited. In the latter case, HMGB1 is a prominent member of damage-associated molecular patterns (DAMPs) which is released during brain damage, and its binding activity with the DNA is known to induce inflammatory signalling. A number of studies have also shown that HMGB1 can be passively released from necrotic cells or actively secreted in response to inflammatory signals [α and ICAM-1, respectively, while in the MCAO model, the release of HMGB-1 from neurons at the earliest onset of brain ischemia was demonstrated [γ (PPAR-γ) protein level and the percentage of PPAR-γ-positive cells by UA treatment but also the neuroprotective effect of UA could be ameliorated by a PPAR-γ antagonist (bisphenol A diglycidyl ether). Hence, the anti-inflammatory effect of UA as a mechanism includes suppression of the metalloprotease/antimetalloprotease imbalance through action as PPAR-γ agonist.In another MCAO model in rats see , the ben signals . Workingnstrated . Wang etnstrated  also useβ (Aβ) plaque deposition at the interneuronal space and neurofibrillary tangles primarily by the microtubule-associated protein, tau, phosphorylation. The therapeutic approaches of dementia are one of the most challenging and what we should still consider at its infancy stage despite the great level of understanding in dementia pathology. Numerous review articles are available in this field , and, andβ (AμM). In senescent mice subjected to D-galactose-induced neurotoxicity, UA  has been shown to improve memory (Morris water maze model) along with increased antioxidant enzymes SOD, CAT, glutathione peroxidase (GPx), and glutathione reductase (GR) and reduction in the level of LPO (MDA) [α-Klotho, and peroxisome-proliferator-activated-receptor γ coactivator 1 beta (PGC-1β) protein levels in the isolated hypothalamus  . On the PO (MDA)  have shothalamus . While Ss e.g., –48). The. TheμM).pression .κB, IL-1β, IL-6, and TNF-α levels were all shown to be suppressed [The D-galactose-induced neurodegenerative changes were also shown to display the therapeutic potential of UA through antioxidant and anti-inflammatory mechanisms. In addition to improved behavioral performance in mice in the step-through test and Morris water maze task, treatment with UA was shown to decrease advanced glycation end products (AGEs), receptors for AGEs, ROS, and protein carbonyl levels in the prefrontal cortex . As antippressed .α, IL-1β, IL-2, and IL-6 in the LPS-treated mouse brain was suppressed [κBα phosphorylation and degradation, NF-κB p65 nuclear translocation, and p38 activation in the mouse brain although it did not alter the activation of TLR4, MyD88, ERK, JNK, and Akt.The lipopolysaccharide- (LPS-) induced cognitive deficits are one of the best experimental model to show the link between the therapeutic potential of experimental agents in memory function via anti-inflammatory mechanism. In mice treated with LPS, UA  was shown to improve cognitive deficits in open field, step-through passive avoidance, and Morris water maze tasks, while the level of proinflammatory markers such as COX-2, iNOS, TNF-ppressed . MoreoveκB kinase β/nuclear factor-κB-mediated inflammatory signalling and the restoration of the insulin signalling and PI3K/Akt/mammalian target of rapamycin (mTOR) pathway. Considering the abolition of the observed protective effect by a specific PI3K 110a inhibitor, the classical example of improvement of the insulin signalling pathway relevant to diabetes and/or obesity-mediated insulin resistance and memory deficit was demonstrated for UA. In fact, one of the best-characterised pharmacological effects of UA is related to amelioration of insulin resistance and antidiabetic properties through a variety of mechanisms. In this regard, UA (10 mg/kg) by its own but even better in combination of metformin (150 mg/kg) has been shown, not only to enhance insulin sensitivity but also to improve cognitive impairment [As a model of obesity-induced cognitive impairments, Lu et al.  employedpairment . As one β (Aβ) as a target for AD. The recent disappointment in phase III clinical trials has included major player in the pharmaceutical industry including the Merck, Pfizer, J&J, Eli Lilly, and Roche which all have Aβ as a common target. Numerous explanations may be given for these failures including the patients' heterogeneity in disease pathology, the rather long duration of the disease pathology, Aβ may not even be correlating with disease pathology in some cases, or it may even be too late to target it by the time the disease has progressed or the symptom is displayed by patients. The source of dementia, for example, could be of cortical origin which itself could be of AD or frontotemporal dementia; subcortical dementia of Parkinson's disease (PD), Huntington's disease, or Lewy body dementia origin; vascular; or mixed dementia. These different forms might have some common symptoms but differ in their pathological features and hence might not be overcome by common therapeutic approach. As the principal protein component of the senile plaques and overwhelming experimental evidence including animal studies linking Aβ to neurotoxicity and Alzheimer's disease, however, the amyloid hypothesis as a proof of concept is still as attractive as it has ever been. Inhibition of Aβ formation, removal or clearance, or neuroprotection approach is therefore worthwhile to evaluate the therapeutic potential of natural products for AD.Perhaps one of the most researched and promising proof of concept and also the basis for the spectacular failure rate in the history of drug development is related to amyloid-β25-35 into lateral ventricles of mice, UA  could reverse the behavioral hallmark of AD (Morris water maze test) along with inhibition of lipid peroxidation (MDA level) and enhancement of the antioxidant (glutathione (GSH)) level in the hippocampus [β, IL-6, and TNF-α levels were also ameliorated in the hippocampus. In vitro, ursolic acid isolated from Corni fructus was also shown to ameliorate the β-amyloid(25-35)-induced toxicity in PC12 cells via modulation of the NF-κB signalling pathway [β-induced expression of iNOS and COX-2 was inhibited through blockade of nuclear translocation of the p65 subunit of NF-κB and phosphorylation of IκBα, along with reduced ERK1/2, p-38, and JNK phosphorylation. In PC12 neuronal cells, the increase in free radical production, LPO, and apoptosis induced by Aβ could also be reversed by UA isolated from Origanum majorana L. [When learning and memory deficits in mice were induced by injection of aggregated Apocampus . The inf pathway . Hence, orana L. , 57.β protein interactions with its receptor CD36: the interaction of Aβ to CD36 could be inhibited by ursolic acid up to a maximal inhibition level of 64% at 20 μM [β , in, inβ proOriganum majorana as a promising acetylcholinesterase (AChE) inhibitor from their screening studies on 139 plant species. A further attempt to identify the active principles led to the identification of UA as an active principle which displayed the in vitro IC50 value of 7.5 nM in comparison to 1 nM for tacrine. With the hope of increasing potency, UA-derived hydroxyl-propinyl derivatives have been synthesised and 2-methyl-3-oxo-methyl-ursoloate, for example, as an AChE and butyrylcholinesterase inhibitor in the lower micromolar range has been reported [Chung et al.  identifireported . Since AThe role of inflammation in anxiety and mood disorders has been well established. A review of clinical and translational data has consistently shown that inflammation could induce the effect on the basal ganglia and cortical reward and motor circuits leading to a reduced level of motivation and motor activity, while the effects of proinflammatory cytokines on monoamines and glutamate could affect the anxiety-related brain regions including amygdala, insula, and anterior cingulate cortex . This reNepeta sibthorpii Bentham, Taviano et al. [The anticonvulsant properties of UA have also been shown in various animal models of epilepsy and seizures. The seizure models in mice employed by Nieoczym et al.  includedo et al.  have alsd-aspartate (NMDA) receptor antagonism with the classical example of ketamine as antidepressant agent. The opioid system has been shown to be involved in the antidepressant-like effect of agents such as folic acid [Considering the role of monoaminergic neurotransmitters  in the mood physiology and depressive-like pathologies, attempts have also been placed to characterise the involvement of various neurotransmitter pathways in UA's pharmacology. It is also worth noting that our current pharmacotherapy options for depression are largely based on enhancement of the monoamine transmission system by using selective neuronal reuptake inhibitors of key transmitters such as serotonin or noradrenaline or inhibition of monoamine transmitters degrading enzyme, monoamine oxidase (MAO). The antidepressant therapeutic approach also involve the N-methyl-lic acid  or in thlic acid .1 and D2 receptor activation [1A receptor) synergism [The tail suspension test (TST) and forced swimming test (FST) are two classical animal models of antidepressant-like effect evaluations where UA showed potent activity. The study by Machado et al. , for exativation . In a sitivation , 79 demoynergism .2+/calmodulin-dependent protein kinase II (CAMK-II) (KN-62), protein kinase C (PKC) (chelerythrine), and mitogen-activated protein kinase kinase 1/2 (MEK1/2) (U0126 or PD98059) inhibitors but not PI3K (wortmannin or LY294002) inhibitors. Hence, this data is in agreement with the induction of antidepressant-like effects by drugs through the activation of kinases such as PKA [The antidepressant-like effects of UA in mice were also demonstrated at just a small dose as 0.1 mg/kg and even through an oral route . Throughh as PKA , PKC [83h as PKA . Although as PKA .Artemisia indica, UA has been shown to display anticonvulsant, antidepressant, and anxiolytic activities in mice. While UA was a positive modulator of α1β2γ2L γ-aminobutyric acid (GABA)-A receptor, the observed anxiolytic activity of the compound could be ameliorated by flumazenil suggesting that it acts through the benzodiazepine-binding site of GABA receptors [P. vulgaris has also been shown to enhance the pentobarbital-induced sleeping time in mice: an effect which was abolished by GABA receptor antagonist, bicuculline. At fairly small doses  administered prior to pentobarbital, the effect of UA was shown to be associated with activation of GABAA receptors by increasing GABA concentrations in brain tissues [μg/mL was rather weak [As one of the active principles of eceptors . UA isol tissues . Such efher weak .β-hydroxylase (214 μmol/L), weak inhibition of MAO-B (780 μmol/L), and no inhibition against MAO-A [In mice treated with UA , anxiolytic-like effect has been reported for the highest dose with increased total time in the center, decreased number of rearing responses in the open-field test, and an increased percentage of entries and total time spent in the open arms of elevated plus maze. This effect was also reported to be similar with diazepam  . Finallyst MAO-A . The higβ and TNF-α along with ROS from overactivated microglial cells has long been known to orchestrate the PD pathology  which is characterised by the progressive loss of dopaminergic neurons in the substantia nigra region of the brain along with the formation of intracellular Lewy bodies (LBs) in viable neurons. The production of excessive amount of proinflammatory cytokines such as IL-1y e.g., –94). Oth. Othβ any . The transport and subsequent accumulation of MPP+ in dopaminergic neurons leading to amelioration of the mitochondrial electron transport system through interaction with complex I attribute to induction of PD in experimental animals. Hence, MPP+ diminishes the mitochondrial power to generate ATP [Animal models of PD are based on induction of oxidative stress and mitochondrial dysfunction by neurotoxins such as MPTP, rotenone, and paraquat. Upon entry into the CNS, MPTP is converted to MPPrate ATP  and rathrate ATP , 103 andrate ATP  signalliThe MPTP-induced PD mouse model has been used to study the effect of UA . The treatment at the most effective dose of 25 mg/kg was shown to improve behavioral deficits, restored altered dopamine level, and protect dopaminergic neurons in the MPTP-intoxicated mouse . It alsoκB activation as well as atherosclerosis development in mice [Direct ROS scavenging or their formation through metal chelation is a structural attribute endowed by phenolic compounds. Accordingly, compounds that possess the catechol functional group such as caffeic acids  and thei in mice , inhibit in mice , cytokin in mice , or cyto in mice  have als4-) induced liver damage in mice [The antioxidant and anti-inflammatory effects of UA were demonstrated in hepatoprotection through multiple pathways including antihyperlipidemic effect , the car in mice –130, hig in mice , ethanol in mice , liver t in mice , and LPS in mice . The ren in mice , ischemi in mice , and chr in mice .α, IL-1β, and IL-6 in the kidney from septic mice [κB and STAT3 inhibition [UA ameliorates autoimmune arthritis , acute itic mice ; sepsis tic mice ; LPS-indtic mice ; and varhibition  have beeBoth as a component of common fruits, herbs, and medicinal plants as well as dietary supplements, UA is a natural product that has been safely used by humans in various forms. Among the plethora of pharmacological effects shown for UA is anti-inflammatory and antioxidant mechanisms in cellular and animal models. In parallel with its effects as antidiabetic, antiobesity, antihyperlipidemic, and hepato-, cardio-, and renoprotective agent and in chronic inflammation  models, the CNS effect of UA has also been demonstrated. The brain injury, cerebral ischemia, cognition deficit, anxiety, and depression are used in this communication to appraise the therapeutic potential of UA. The antioxidant and anti-inflammatory mechanisms play a pivotal role for UA's effect while other mechanisms include specific effect on neurotransmitter uptake, receptor modulation, and enzyme inhibition, primarily MAO and AChE. In view of such a diverse pharmacological effect/efficacy, a further lead optimisation study by using UA as a prototype drug candidate is well merited.


Helianthus annuus) seeds and equipped with radio frequency identification (RFID) data loggers that recorded >315,000 visits by 70 individual Black‐capped Chickadees (Poecile atricapillus) across a 5‐month period (October 2016–March 2017). We found extensive variation in feeder use, with individuals averaging 1–406 feeder visits/day and using 1–9 of the 21 feeders that were available; individual variability was largely consistent during the course of our study. At the population level, we found that feeder use decreased from the start of our study, and this decline continued through the period when foraging was most limited by daylight, including the winter solstice. In contrast to theoretical predictions and empirical work in continental climates, we found that weather variables did not drive feeder use and that feeder visits peaked at mid‐day and gradually decreased until sunset. Our study indicates that individual‐level differences combined with seasonality to drive feeder use patterns, and we conclude that use of supplemental feeders during winter in Mediterranean climates appears to differ notably from feeder use in continental climates.Purposeful provisioning of food to wild animals is a widespread and growing activity that has the potential to impact populations and communities. Nevertheless, studies assessing use of recreational feeders by free‐living birds during winter are surprisingly rare and largely limited to regions with continental climates characterized by freezing temperatures and snow cover. In contrast, there is little information available regarding bird use of feeders within warmer climates during winter, despite widespread recreational feeding in these areas. In this study, we quantified visitation patterns to bird feeders in a Mediterranean climate to evaluate the relationship between feeder use and several environmental variables known to influence supplemental feeder use in continental climates. We established a network of bird feeders in Corvallis, Oregon, USA, that were filled with black oil sunflower ( Given the strong influence of local environmental conditions on feeder use demonstrated by previous investigations, particularly weather  during winter in a Mediterranean climate. Such climates are characterized by mild, rainy winters with no regular snow cover and temperatures above freezing , Himalayan blackberry (Rubus discolor), bigleaf maple (Acer macrophyllum), poplar (Populus spp.), and willow  and contained a mixture of native shrubs, grasses, and forbs. We selected feeder locations that were a minimum of 50 m from buildings, and although it is possible that our tagged birds could have accessed feeders other than those established for our study, we found that there was no evidence that use of individual feeders varied relative to their distance to the nearest building . We placed feeders at 200‐m intervals along the Oak Creek riparian area such that the two most distant feeders were 3.2 km away from each other; this distance is within the range of what an individual chickadee could theoretically cover in the course of our study period based on previous work with homing experiments conducted during winter Odum,  and studWe selected the chickadee for this study because this species (a) is a small‐bodied songbird (10–14 g) with high energetic needs during the nonbreeding season  from 08:00 to 17:00 PST on fair days  using a combination of mist‐nets and traps that were affixed to feeders. We PIT‐tagged a total of 174 chickadees that were available for this study; 86 birds were captured during pilot work undertaken during October 2015–January 2016, and 88 birds were captured from October 2016–January 2017. We fitted each captured individual with a unique combination of legs bands that consisted of a USGS aluminum leg band, a colored plastic leg band, and a colored band that contained a uniquely numbered PIT tag . At initial capture, we also measured body mass and right tarsus length to assess variation in size among individuals.Sciurus griseus) and the Douglas squirrel (Tamiasciurus douglasii). We also fitted feeders with a 10 × 15 cm wire mesh trap attached around the feeding portal to capture individual chickadees for tagging. Each feeder was capable of holding approximately 3 kg of unhulled black oil sunflower (Helianthus annuus) seeds, and we provided food ad libitum in all feeders throughout the course of the study. On the base of each feeder, we attached a small waterproof box that housed a 12‐volt battery for power and an RFID data logger . Thus, we concluded that feeder use was not linked to escape cover immediately surrounding feeders and therefore did not consider vegetative cover in any subsequent analyses.Feeder use by birds may be influenced by nearby vegetation used to hide from predators , average daily wind speed , and total daily precipitation . In addition, we obtained sunrise and sunset times for the location of the weather station from the Astronomical Applications Department of the U.S. Naval Observatory  by the National Oceanic and Atmospheric Administration NCEI,  for each2.5n = 20) of hulled black oil sunflower seeds taken from the pool of seeds used in feeders in our study. Initially, the sample was separated into two equal groups  and analysis took place on a 0.2 g sample of dried and ground sunflower seeds from each group. Next, samples were combined with 4 ml 50% MeOH:H2O with 1% HCl, and 450 µl 17:1 of FFA IS2, an internal standard added to all samples to aid with quantitation. After 10 min of vortexing and sonication, 4 ml of chloroform was added, followed by a second 10‐min vortex and sonicate session, and then centrifuged 10 min at 1,000 G. After saving the lower layer, the upper layer was re‐extracted in the same manner as above. The lower layer was then combined with the re‐extracted upper layer, and a 3 ml 0.88% KCl solution was added, followed by 5 min of vortexing and sonication, then centrifuged 10 min at 2,000 G to achieve phase separation. The upper layer was removed and discarded, chloroform:MeOH 2:1 was added, the sample was dried under N2, and then the extracted lipids were weighed. The lipid extraction yielded an average of 0.26 kcal of fat per seed.To determine the amount of potential energy that chickadees acquired from feeders, we had extraction analysis performed by the Linus Pauling Institute at Oregon State University on a haphazardly selected sample , hereafter termed “total daily visits.” We used this metric to assess how feeder use varied between individual chickadees and quantify the extent to which it was linked to weather variables. To quantify individual‐level variation in feeder use, we summarized the distribution of total daily visits for each bird and the number of feeders visited across the season for each bird, using variance estimates of random effects to quantify the ratio of among‐bird variation to within‐bird variation from our statistical model.Tmin, wind speed, precipitation, and photoperiod. Exploratory analysis of data prior to modeling found that the general pattern of response was similar among individual birds; however, the magnitude of the response exhibited large variation, so we included a random effect for each bird in all models. Because total daily visits were measured on multiple days for each bird, we graphically assessed the temporal autocorrelation function of residuals in each of our single‐variable models and found that a first‐order autoregressive model had the best fit for the temporal autocorrelation among total daily visits. We found that mean total daily visits were best modeled with a negative binomial distribution allowing for overdispersion. In addition, our initial graphical assessment of total daily visits relative to weather variables found that mean total daily visits varied differently before and after the winter solstice. Thus, we investigated whether effects of environmental variables differed between the pre‐solstice period when photoperiod was decreasing, and the postsolstice period when photoperiod was increasing. We fit generalized linear mixed models (GLMMs) using the glmmTMB package  and resulted in the shortest foraging days for chickadees during our study. As above, we used a Poisson GLMM with the glmmTMB package , we report the rate at which the mean total daily visits changed with changes in time or weather (slope) and the associated 95% confidence interval. The sample size for all analyses is n = 70 individuals unless otherwise noted.For analyses pertaining to individual variation, we report averages and their associated standard deviations (SDs); for analyses pertaining to variation due to time  or weather , resulting in 315,745 visits across our 160‐day study period. Tagged birds took an average of 11 days  to return to a feeder after their initial capture, and the average time it took birds to visit all feeders they ultimately used during the study was 37 days . Feeders were highly variable in the total number of times they were visited by tagged birds during the study, with an average of 15,035 visits . Similarly, the number of individual birds that used a particular feeder was also highly variable with an average of 11.5 birds . The maximum distance we detected tagged birds moving between feeders was 1,850 m.Of 174 individuals captured and PIT‐tagged at our feeders, 70 birds returned and were detected by RFID data loggers  which equated to 66% of the study period. Over the course of the study, the number of visits to any single feeder by an individual bird ranged from 1 to 15,512, and individuals averaged 4–9,831 visits per feeder . We found substantial variability in total daily visits among individual chickadees, with an average of 44 visits/day .Of the 160 days that feeders were available to chickadees, individuals visited feeders an average of 103 days  or summed total daily visits  visited only 2–4 feeders during the entire study period . Thus, we found no evidence that weather variables were linked to our measure of daily feeder use. During our study average daily Tmin was 2.1°C, average daily wind speed was 8.7 km/hr, and average daily precipitation was 6.6 mm, all of which were similar to 30 years averages .We found strong support for an effect of the hour since sunrise on total hourly visits compared to the null model (∆AIC = 490.8). Total hourly visits rapidly increased after sunrise, peaked during 3–5 hr after sunrise, and then gradually decreased until sunset Figure . In parton Table ; Tmin, 4Parus major) and Blue Tit  that has been found in previous studies within continental climates. Our findings regarding temperature are concordant with results from use of feeders by chickadees in Maine, USA (45°N), where feeder use was found to be unaffected by ambient temperature despite markedly colder conditions than those in our study area  found differences in visitation patterns to supplemental feeders whereby more visits were made early in the day when environmental conditions were harsher at higher elevation sites relative to lower elevation sites where visits were spread more evenly across daylight hours , variation in the diurnal pattern of feeder use across regions suggests that small birds regulate their energy intake based on local conditions. In line with this, recent work in the closely related Mountain Chickadee  may have been used by our PIT‐tagged birds; however, we find that this possibility, if true, was unlikely to exert a strong influence on our results. First, all of our study feeders were placed on agricultural lands owned by Oregon State University, and therefore, few of our feeders were placed near residential homes; instead, the closest buildings were university‐owned buildings that had a low likelihood of harboring recreational feeders. Second, we found no relationship between the number of visits that birds made to our feeders and the distance to the nearest building. If recreational feeders were present at nearby buildings and reduced feeder visits by tagged birds in our study, we would have expected a relationship where the number of feeder visits would decline as distance to building decreased. That we found no evidence of such a relationship suggests that nearby buildings—assuming that they harbored recreational feeders—did not serve to influence birds visiting our feeders. Finally, all of our study feeders were located within 3.2 km of one another, and chickadees displaced from winter flocks can move up to 2.8 km in a single 24‐hr period Odum, . Moreove5Our study in a Mediterranean climate found large variation among individuals in the extent of their use of supplemental bird feeders during winter, with limited influence of weather‐related variables that have been linked to feeder use patterns in continental regions experiencing colder winters. In particular, our study suggests that temperature may play a lesser role in driving the use of feeders by birds in warmer regions such as the Mediterranean climate in which we worked, perhaps because weather conditions were insufficient to impose strong energetic challenges to individuals. Nevertheless, this finding has implications for feeder use patterns in mild climates, as well as in continental climates where climate change is expected to result in winter warming (Zuckerberg et al., None declared.JLL, JWR, and LMG conceptualized and designed the study; JLL conducted field data collection; JLL and LMG conducted statistical analyses, with input from JWR; all authors were involved in writing and editing the manuscript. Click here for additional data file. Click here for additional data file.