Regular physical activity followed by detraining increases the sensitivity of global gene expression to acute exercise stress
ABSTRACT: To determine the influence of a previous physcial activity period (e.g., exercise) on global gene expression, we compared differential expression in sedentary (SED) and detrained (DETR) rats relative to trained (TR) rats with regular access to physcial activity. TR and DETR rats had voluntary access to caged running wheels for 8 and 4 weeks, respectively. DETR rats were moved to sedentary conditions (normal cage activity) for another 4 weeks. SED rats experienced 8 weeks of normal caged activity; n=8 per group. At the end of each group's respective 8 weeks, all rats underwent 1 hr of moderate of acute exercise stress (e.g., forced wheel running at a speed of 20 m/min). Soleus muscles were harvested 24h post-running.
ORGANISM(S): Rattus norvegicus
SUBMITTER: Elisa J Bienenstock Emily A Brown Jon-Philippe K. Hyatt Gary E McCall Jon-Philippe K Hyatt
Project description:To determine the influence of a previous physcial activity period (e.g., exercise) on global gene expression, we compared differential expression in sedentary (SED) and detrained (DETR) rats relative to trained (TR) rats with regular access to physcial activity. Overall design: TR and DETR rats had voluntary access to caged running wheels for 8 and 4 weeks, respectively. DETR rats were moved to sedentary conditions (normal cage activity) for another 4 weeks. SED rats experienced 8 weeks of normal caged activity; n=8 per group. At the end of each group's respective 8 weeks, all rats underwent 1 hr of moderate of acute exercise stress (e.g., forced wheel running at a speed of 20 m/min). Soleus muscles were harvested 24h post-running.
Gene expression data from 16-month and 3-month old male rats, with three different levels of activity over the life span: sedentary, twice weekly physical activity, regular running wheel exercise.
Project description:Gene expression data at rest and immediately post 30 min submaximal exercise in 3 month and 16 month old male rats, some of which were sedentary (SED), had access to a physical activity box twice weekly (PA) and some of which had daily access to a running wheel (EX). We used microarrays to detail global gene expression underlying select health-related phenotypes and identified differentially expressed genes among the three groups. Young (3 month) and old (16 month) male rats were separated into three different groups: Sedentary (SED), twice-weekly physical activity (PA), and regular exercise (EX). Animals were sacrificed either at rest or after 30 min of sub maximal exercise. Then, a portion of cardiac tissue was collected for RNA extraction and hybridization on Affymetrix microarrays.
Expression data from female SD rats with access to lifelong exercise
Project description:Gene expression and phenotypic consequences of laboratory housing in rats. Disease related-phenotypes and associated gene expressions of sedentary animals (living solely in a standard cage) were compared with animals that had access to twice-weekly one-hour physical activity in a large box (PA) and with those that had access to voluntary running wheel exercise (EX). Keywords: exercise dose reponse, sedentary, twice weekly physical activity, daily exercise Overall design: The left ventricle of 16 month female Sprague-Dawley rats was used for RNA extraction and hybridization on Affymetrix GeneChip Rat Genome 230 2.0 Arrays. Twelve animals from each treatment group (SED, PA, and EX) were used for microarray analysis (4 animals pooled per GeneChip).
Endurance training in early life results in long-term programming of heart mass in rats
Project description:This study aimed to examine if early life exercise could normalize the reduced heart mass we have previously observed in the adult hearts from growth restricted rats. We investigated the molecular pathways using microarray analysis to explain how endurance exercise in early life might be regulating the sustained increase in heart mass we have observed in these rats in adulthood. At 5 weeks of age, male WKY rats were allocated to one of the following exercise treatments: remained sedentary with post mortem (PM) at 9 or 24 weeks, early exercise training (from 5-9 weeks of age) with PM at 9 or 24 weeks, or later exercise training (from 20-24 weeks of age) with PM at 24 weeks (n=8 males/group). Exercise training involved treadmill running 5 days/ week for 4 weeks. Running duration progressively increased from 20 up to 60 minutes per day, with the treadmill speed set at 15 m/min for the first week and 20 m/min thereafter. At 9 or 24 weeks of age rats were killed with an intraperitoneal injection of Ilium Xylazil-20 (30 mg/kg) and Ketamine (225 mg/kg). The rats in the 9 week old early exercise and 24 week old later exercise groups were killed 72 hours following the last bout of treadmill running. Total RNA was obtained from the whole-hearts for analysis Total RNA obtained from the hearts of WKY rats. Male offspring remained sedentary or underwent treadmill running from 5-9 weeks (early exercise) or 20-24 weeks of age (later exercise).
Transcription profiling of rat heart ventricle samples from animals subjected to differing exercise regimes
Project description:Gene expression and phenotypic consequences of laboratory housing in rats. Disease related-phenotypes and associated gene expressions of sedentary animals (living solely in a standard cage) were compared with animals that had access to twice-weekly one-hour physical activity in a large box (PA) and with those that had access to voluntary running wheel exercise (EX). Experiment Overall Design: The left ventricle of 16 month female Sprague-Dawley rats was used for RNA extraction and hybridization on Affymetrix GeneChip Rat Genome 230 2.0 Arrays. Twelve animals from each treatment group (SED, PA, and EX) were used for microarray analysis (4 animals pooled per GeneChip).
Left ventricle transcriptomic analysis reveals the initial decline in VO2peak from its lifetime apex associates with connective tissue accumulation
Project description:Peak oxygen consumption (VO2peak) strongly predicts morbidity and mortality better than other established risk factors, yet all mechanisms associated with its age-related decline are unknown. Our lab has shown that VO2peak first begins to decrease at the same age of 19 weeks old in Wistar in both sedentary and wheel-running, female Wistar rats. Here, we employed RNA-sequencing to determine the extent to which transcriptomic alterations in the left ventricle associate with age-related decreases in VO2peak. Transcriptomic comparisons were made within both sedentary (SED) and wheel-running (RUN) rats between 19 and 27 wks (n= 5-8/group).
Effects of Voluntary Exercise on Hippocampal Gene Expression in male C57Bl/6J mice
Project description:This experiment was designed to identify changes in gene expression in the brain (specifically the hipocampus) in relation to variable levels of voluntary exercise. Male C57Bl/6J mice were weaned onto a low fat diet (LF; Research Diets D12329, 11% kcal fat) and given continuous access to exercise wheels (30.3 x 20.6 x 26 cm; Mini Mitter®, Nalgene® Activity Wheel for Rodents) at ten weeks of age, for three days (n=96). Six mice had their wheels locked to act as sedentary controls (sed). Animals were considered to be high runners (HR) if they ran >= 5 km/night and low runners (LR) if they ran <= 2 km/night. Middle runners (MR) were chosen randomly from the population of animals falling between the high and low groups. This series is comprised of array results from three parallel experiments comparing HR versus sed, MR versus sed, and HR versus LR. Six hybridizations were performed for each of the three comparisons (3 forward-labeled, 3-reverse labeled) to account for dye-incorporation differences. One slide from the HR vs LR experiment was broken during processing, so only five are included from that group. Keywords = hippocampus Keywords = voluntary running Keywords = voluntary exercise Keywords = C57Bl/6J Keywords: parallel sample
Analysis of hippocampal gene expression in adult and aged male BABL/c mice with or without running wheel access
Project description:Currently, the mechanisms behind the anti-aging effects of exercise are not understood. The presented study conducted a microarray on hippocampal samples from adult (3.5 month-old) and aged (18 month-old) male BALB/c mice that were individually housed with or without running wheels for 8 weeks. Results showed that aging altered genes related to chromatin remodeling, cell growth, immune activity, and synapse organization compared to adult mice. Exercise was found to modulate many of the genes altered by aging, but in the opposite direction. For example, wheel running increased expression of genes related to cell growth and attenuated expression of genes involved in immune function and chromatin remodeling. Collectively, findings show that even late-onset exercise may attenuate age-related changes in gene expression and identifies possible pathways through which exercise may exert its beneficial effects. In total 20 samples (4 aged exercise, 4 aged sedentary, 6 adult exercise, and 6 adult sedentary) plus 4 technical replicates (24 total) were analyzed.
Down-regulation as the dominant hippocampal gene expression profile with voluntary resistance wheel running by DNA microarray analysis
Project description:Exercise improves brain function enhancing neuronal plasticity and cognitive enhancement. For voluntary resistance wheel running (RWR) exercise, with a load of 30% of body weight, we reported enhancement of neurogenesis and spatial memory associated with hippocampal brain-derived neurotrophic factor (BDNF) signaling compared to wheel running (WR) without a load (Lee et al., 2012; Lee et al., 2013). Despite these new evidences, mechanisms for RWR-induced improvement of hippocampal function remained to be clarified. In the present study, we have utilized the high-throughput DNA microarray approach to gain deep insight into molecular mechanisms underlying these changes that could be novel targets of RWR-induced hippocampal plasticity. To do so, whole genome (4x44K) high-density oligonucleotide microarrays were used to monitor the expression level of gene transcripts in the hippocampus of rats voluntary running for 4 weeks in comparison with sedentary animals. These rats showed a significant decrease in average running distance although average work levels immensely increased 12-fold in the RWR group, resulting in muscular adaptation for the fast-twitch plantaris muscle. DNA microarray analysis revealed that 122 (sedentary x WR) and 157 (sedentary x RWR) genes were up-regulated (> 1.5-fold change) as compared with 97 (sedentary x WR) and 467 (sedentary x RWR) down-regulated genes (< 0.75-fold change). Functional categorization using the Ingenuity Pathway Analysis (IPA) revealed expression pattern changes in the major categories of disease and disorders, molecular functions and physiological system development and function. Among these, RWR up-regulated genes such as NFATc1, AVPR1A and FGFR4, which are crucial role for neuronal development and its functions. The down-regulated inflammatory cytokines (IL1B, IL10, IL2RA, TNF) and chemokines (CXCL1, CXCL9, CXCL10, CCL2, CCL13, CCR4) might be important to neuronal dysfunction and vulnerability. Taken together, these gene candidates are suggested to play a critical role in hippocampal plasticity. This is a first study presenting not only new information into the voluntary RWR influenced transcriptome in the rat hippocampus, but also provides a hypothesis for the RWR influenced enhancement in brain function. Overall design: 10-week-old male Wistar rats were randomly allocated to three groups: (1) housed in standard cages and used as non-active controls (sedentary, n = 10), (2) wheel running with no resistance (WR, n = 8), and (3) housed in cages with resistance running wheels with an adjustable resistance (RWR, n = 8). Rats of both running wheel groups (WR and RWR) were housed individually and had free access to a specially designed running wheel apparatus for 24 h/day. Between 08:00 and 12:00 on the day after the final day of exercise, the animals were immediately decapitated using a guillotine. The hippocampi were rapidly dissected, snap frozen in liquid nitrogen and stored at —80°C prior to further analysis. The deep-frozen hippocampi were transferred to a precooled (in liquid nitrogen) mortar and ground with a pestle to a very fine powder with liquid nitrogen. Total RNA was extracted and validated followed by checking subsequently synthesized cDNA by RT-PCR. A rat 4x44K whole genome oligo DNA microarray chip was used for global gene expression analysis using the hippocampi. Fluorescently labeled targets of Sed, WR and RWR samples were hybridized to the same microarray slide with 60-mer probes. A flip labeling (dye swap or reverse labeling with Cy3 and Cy5 dyes) procedure was followed to nullify the dye bias associated with unequal incorporation of the two Cy dyes into cDNA. Briefly, to select differentially expressed genes, we identified genes that were up regulated in chip 1 (Cy3/Cy5 label for sedentary and WR, respectively) but down regulated in chip 2 (Cy3/Cy5 label for WR and sedentary, respectively) for the hippocampus. The same selection criteria were applied for chips 3-4 (sedentary and RWR). Hybridization and wash processes were performed according to the manufacturer's instructions, and hybridized microarrays were scanned using an agilent microarray scanner. The functional and network analysis were generated through the use of IPA (Ingenuity® Systems, www.ingenuity.com). To validate gene changes in array data and test the BDNF signaling-related molecules and expression of select transcripts were determined by quantitative real-time RT-PCR.
Project description:Exercise improves brain function enhancing neuronal plasticity and cognitive enhancement. For voluntary resistance wheel running (RWR) exercise, with a load of 30% of body weight, we reported enhancement of neurogenesis and spatial memory associated with hippocampal brain-derived neurotrophic factor (BDNF) signaling compared to wheel running (WR) without a load (Lee et al., 2012; Lee et al., 2013). Despite these new evidences, mechanisms for RWR-induced improvement of hippocampal function remained to be clarified. In the present study, we have utilized the high-throughput DNA microarray approach to gain deep insight into molecular mechanisms underlying these changes that could be novel targets of RWR-induced hippocampal plasticity. To do so, whole genome (4x44K) high-density oligonucleotide microarrays were used to monitor the expression level of gene transcripts in the hippocampus of rats voluntary running for 4 weeks in comparison with sedentary animals. These rats showed a significant decrease in average running distance although average work levels immensely increased 12-fold in the RWR group, resulting in muscular adaptation for the fast-twitch plantaris muscle. DNA microarray analysis revealed that 122 (sedentary x WR) and 157 (sedentary x RWR) genes were up-regulated (> 1.5-fold change) as compared with 97 (sedentary x WR) and 467 (sedentary x RWR) down-regulated genes (< 0.75-fold change). Functional categorization using the Ingenuity Pathway Analysis (IPA) revealed expression pattern changes in the major categories of disease and disorders, molecular functions and physiological system development and function. Among these, RWR up-regulated genes such as NFATc1, AVPR1A and FGFR4, which are crucial role for neuronal development and its functions. The down-regulated inflammatory cytokines (IL1B, IL10, IL2RA, TNF) and chemokines (CXCL1, CXCL9, CXCL10, CCL2, CCL13, CCR4) might be important to neuronal dysfunction and vulnerability. Taken together, these gene candidates are suggested to play a critical role in hippocampal plasticity. This is a first study presenting not only new information into the voluntary RWR influenced transcriptome in the rat hippocampus, but also provides a hypothesis for the RWR influenced enhancement in brain function. 10-week-old male Wistar rats were randomly allocated to three groups: (1) housed in standard cages and used as non-active controls (sedentary, n = 10), (2) wheel running with no resistance (WR, n = 8), and (3) housed in cages with resistance running wheels with an adjustable resistance (RWR, n = 8). Rats of both running wheel groups (WR and RWR) were housed individually and had free access to a specially designed running wheel apparatus for 24 h/day. Between 08:00 and 12:00 on the day after the final day of exercise, the animals were immediately decapitated using a guillotine. The hippocampi were rapidly dissected, snap frozen in liquid nitrogen and stored at —80°C prior to further analysis. The deep-frozen hippocampi were transferred to a precooled (in liquid nitrogen) mortar and ground with a pestle to a very fine powder with liquid nitrogen. Total RNA was extracted and validated followed by checking subsequently synthesized cDNA by RT-PCR. A rat 4x44K whole genome oligo DNA microarray chip was used for global gene expression analysis using the hippocampi. Fluorescently labeled targets of Sed, WR and RWR samples were hybridized to the same microarray slide with 60-mer probes. A flip labeling (dye swap or reverse labeling with Cy3 and Cy5 dyes) procedure was followed to nullify the dye bias associated with unequal incorporation of the two Cy dyes into cDNA. Briefly, to select differentially expressed genes, we identified genes that were up regulated in chip 1 (Cy3/Cy5 label for sedentary and WR, respectively) but down regulated in chip 2 (Cy3/Cy5 label for WR and sedentary, respectively) for the hippocampus. The same selection criteria were applied for chips 3-4 (sedentary and RWR). Hybridization and wash processes were performed according to the manufacturer's instructions, and hybridized microarrays were scanned using an agilent microarray scanner. The functional and network analysis were generated through the use of IPA (Ingenuity® Systems, www.ingenuity.com). To validate gene changes in array data and test the BDNF signaling-related molecules and expression of select transcripts were determined by quantitative real-time RT-PCR.