Project description:Here we describe a genome-wide analysis of DNA-methylation in muscle of trained mice. In comparison to sedentary controls 2762 genes exhibited differentially methylated CpGs in their putative promoter regions. The majority of these genes were related to muscle growth and differentiation and a minor fraction involved in metabolic regulation. These findings suggest that DNA-methylation is involved in the regulation of muscle adaptation to regular exercise training. Reduced representation bisulfite sequencing of murine quadriceps muscle
Project description:Consequence of physical exercise in skeletal muscle was investigated in C57BL/6 mice after 4 weeks of exercise training and compared to sedentary controls. Exercised mice received four 4 weeks of regular exercise training on a motorized treadmill and were compared to sedentary controls. 6 mice of each Treatment were used to extract RNA from the quadriceps muscle three hours after the last training bout
Project description:Endurance exercise training has been shown to decrease whole-body and skeletal muscle insulin resistance and increase glucose tolerance in conditions of both pre-diabetes and overt type 2 diabetes. However, the adaptive responses in skeletal muscle at the molecular and genetic level for these beneficial effects of exercise training have not been clearly established in an animal model of pre-diabetes. The present study identifies alterations in skeletal muscle gene expression that occur with exercise training in pre-diabetic, insulin-resistant obese Zucker (fa/fa) rats and insulin-sensitive lean Zucker (Fa/-) rats. Treadmill running for up to 4 weeks caused significant enhancements of glucose tolerance as assessed by the integrated area under the curve for glucose (AUCg) during an oral glucose tolerance test in both lean and obese animals. Using microarray analysis, a set of only 12 genes was identified as both significantly altered (>1.5-fold change relative to sedentary controls; p<0.05) and significantly correlated (p<0.05) with the AUCg. Two of these genes, peroxisome proliferator-activated receptor-g coactivator 1a (PGC-1a) and the z-isoform of protein kinase C (PKC-z), have known involvement in the regulation of skeletal muscle glucose transport. We confirmed that protein expression levels of PGC-1a and PKC-z were positively correlated with the mRNA expression levels for these two genes. Overall, this study has identified a limited number of genes in soleus muscle of lean and obese Zucker rats that are associated with decreased insulin resistance and increase glucose tolerance following endurance exercise training. These findings could guide the development of pharmaceutical M-^Sexercise mimeticsM-^T in the treatment of insulin-resistant, pre-diabetic or overtly type 2 diabetic individuals.
Project description:Seventy two rats were randomized to twelve independent groups of rats (n = 6 in all groups) where half of the rats were chosen for training (treadmill exercise training 1.5 hour 5 days a week, in 1, 4, 24, 48 days and for 4 and 8 weeks) or sedentary (no training) as described in detail by Wisloff et al. (Intensity-controlled treadmill running in rats: VO(2 max) and cardiac hypertrophy. Am J Physiol Heart Circ Physiol. 2001 Mar;280(3):H1301-10.) or Kemi et al.(Aerobic fitness is associated with cardiomyocyte contractile capacity and endothelial function in exercise training and detraining. Circulation. 2004 Jun 15;109(23):2897-904. Epub 2004 Jun 1.). The rats were scarified one hour after training (1, 4, 24 and 48 days) or 24 hours after training (4 and 8 weeks). Biopsies form left ventricle was taken form all rats and stored on -80°C for preparation of RNA. The same procedures were performed for the control/sedentary rats which were sacrificed at the same time as the exercised rats.
Project description:Exercise is a fundamental component of human health that is associated with greater life expectancy and reduced risk of chronic diseases. While the beneficial effects of endurance exercise on human health are well established, the molecular mechanisms responsible for these observations remain unclear. Endurance exercise reduces the accumulation of mitochondrial DNA (mtDNA) mutations, alleviates multisystem pathology, and increases the lifespan of the mtDNA mutator mouse model of aging, in which the proof-reading capacity of mitochondrial polymerase gamma (POLG1) is deficient. Clearly, exercise recruited a POLG1-independent mtDNA repair pathway to induce these adaptations, a novel finding as POLG1 is canonically considered to be the sole mtDNA repair enzyme. Here we investigate the identity of this pathway, and show that endurance exercise prevents mitochondrial oxidative damage, attenuates telomere erosion, and mitigates cellular senescence and apoptosis in mtDNA mutator mice. Unexpectedly, we observe translocation of tumour suppressor protein p53 to mitochondria in response to endurance exercise that facilitates mtDNA mutation repair. Indeed, endurance exercise failed to prevent mtDNA mutations, induce mitochondrial biogenesis, preserve mitochondrial morphology, reverse sarcopenia, and mitigate premature mortality in mtDNA mutator mice with muscle-specific deletion of p53. Our data establish an exciting new role for p53 in exercise-mediated maintenance of the mtDNA genome, and presents mitochondrially-targeted p53 as a novel therapeutic modality for aging-associated diseases of mitochondrial etiology. Microarray analysis of gene expression from skeletal muscle (quadriceps femoris) from Mus musculus. N=23 samples per treatment were analysed for whole transcriptiome gene expression profile using NimbleGen Arrays. The treatment groups included wild-type C57Bl/6J mice as the control group, then two treatment groups which both contained homozygous knock-in mtDNA mutator mice (PolG; PolgAD257A/D257A). Once group of these heterozygous knock out mice received regular endurance exercise sessions while the other group remained sedentraty for 6 months. The control group specimens were wild-type litter mates to the transgenic knockout mice.
Project description:Dahl salt-sensitive (DS) rats were obtained from Harlan Sprague Dawley Laboratory at 5 weeks of age. At 6 weeks of age, physiologic cardiac hypertrophy was generated by a; vigorous daily exercise regimen for 6 weeks (e group). The exercise protocol is based on those described previously with modifications (Wisloff U et al., 2001; Jin H et al., 1994). Rats were exercised daily for 6 weeks on a rodent treadmill (Exer-6M; Columbus Instruments). The exercise program consisted of three weeks of progressively strenuous exercise regimens; followed by three weeks of maintenance period, during which the rats were exercised at 16 m/min at a 5o incline for 90 minutes/day. All rats completed the exercise protocol. Pathological cardiac hypertrophy was generated by feeding a 6% NaCl diet to DS rats at 6 weeks of age (h group) (Inoko M et al., 1994). Control rats (c group) were age matched and sedentary DS rats fed normal rat chow. Read more at http://cardiogenomics.med.harvard.edu/groups/proj1/pages/rat_home.html<br><br>Note that files GSM11886.txt and GSM12308.txt, and files GSM11887.txt and GSM12309.txt as downloaded from GEO contain identical data.
Project description:Purpose: Aerobic capacity is a strong predictor of cardiovascular mortality. To determine the relationship between inborn aerobic capacity and soleus gene expression we examined genome-wide gene expression in soleus muscle of rats artificially selected for high and low running capacity (HCR and LCR, respectively) over 16 generations. The artificial selection of LCR caused accumulation of risk factors of cardiovascular disease similar to the metabolic syndrome seen in man, whereas HCR had markedly better cardiac function. We also studied alterations in gene expression in response to exercise training in the two groups, since accumulating evidence indicates that exercise has profound beneficial effects on the metabolic syndrome. Methods:; Soleus gene expression of both sedentary and exercise trained HCR and LCR was characterized by microarray- and gene ontology analysis. Results: Although HCR and LCR had an inborn 347% difference in running capacity, only three genes were found differentially expressed in the soleus muscle between the two groups. Up-regulation of the mitochondrial enzyme leucyl-transferRNA synthetase (LARS2) was found in the sedentary LCR. Increased expression of LARS2 has been associated with a mitochondrial DNA mutation linked to maternally inherited diabetes and mitochondrial dysfunction. In line with our findings, a growing body of evidence suggests that LCR have compromised mitochondrial function. After exercise training, 58 genes were altered in the soleus muscle of HCR, in contrast to only one in the LCR group. This suggests that animals born with different levels of fitness respond different to the same type of exercise training. Adaptations to exercise in HCR seemed to be associated with increased lipid metabolism and fatty acid elongation in the mitochondria. Also, genes associated with the peroxisomes, seemed to be central in the adaptation to exercise. Conclusion: The results indicate that (i) LCR might have mitochondrial dysfunction, which may be a contributing factor of the low inborn aerobic capacity, (ii) animals born with different levels of fitness respond different to the same exercise program. Experiment Overall Design: There are 16 samples in this study.
Project description:While the salutary effects of exercise training on conduit artery endothelial cells have been reported in animals and humans with cardiovascular risk factors or disease, whether a healthy endothelium is alterable with exercise training is less certain. The purpose of this study was to evaluate the impact of exercise training on transcriptional profiles in normal endothelial cells using a genome-wide microarray analysis. Brachial and internal mammary endothelial gene expression was compared between a group of healthy pigs that exercise-trained for 16-20 weeks (n=8) and a group that remained sedentary (n=8). We found that a total of 130 genes were up regulated and 84 genes down regulated in brachial artery endothelial cells with exercise training. In contrast, a total of 113 genes were up regulated and 31 genes down regulated in internal mammary artery endothelial cells (>1.5-fold and false discovery rate<15%). Although there was an overlap of 66 genes (59 up regulated and 7 down regulated with exercise training) between the brachial and internal mammary arteries, the identified endothelial gene networks and biological processes influenced by exercise training were distinctly different between the brachial and internal mammary arteries. These data indicate that a healthy endothelium is indeed responsive to exercise training and support the concept that the influence of physical activity on endothelial gene expression is not homogenously distributed throughout the vasculature. Brachial and internal mammary endothelial gene expression was compared between a group of healthy pigs that exercise-trained for 16-20 weeks (n=8) and a group that remained sedentary (n=8). The arteries were taken from the same animals, and after quality assessment, so there were 29 total arrays (15 unique pigs), 14 with an array for both the brachial artery and the internal mammary artery (IMA), and the remaining 1 having only brachial. One pig had bad RNA quality and is missing from both IMA and brachical. Therefore, there were 15 IMA (7 SED, 8 EX) and 14 brachial arrays (7 SED, 7 EX) that were used in this study.
Project description:Transcriptome analysis of gastrocnemius muscle RNA samples from exercise and sedentary ancestries Early life and pre-conception environmental stimuli can affect adult health-related phenotypes. Exercise training is an environmental stimulus affecting many systems throughout the body and appears to alter offspring phenotypes. The aim of this study was to examine the influence of parental exercise training, or M-bM-^@M-^\exercise ancestry,M-bM-^@M-^] on morphological and metabolic phenotypes in multiple generations of mouse offspring. F0 C57BL/6 mice were exposed to voluntary exercise or sedentary lifestyle and bred with like-exposed mates to produce an F1 generation. F1 mice of both ancestries were sedentary and sacrificed at 8 wk or bred with littermates to produce an F2 generation, which was also sedentary and sacrificed at 8 wk. Small, but broad generation- and sex-specific effects of exercise ancestry were observed for body mass, fat and muscle mass, serum insulin, glucose tolerance, and muscle gene expression. F1 EX females were heavier than F1 SED females, but F1 SED females had higher absolute tibialis anterior and omental fat masses. Serum insulin was lower in F1 SED females compared to F1 EX females. F2 EX females had impaired glucose tolerance compared to F2 SED females. Analysis of skeletal muscle mRNA levels revealed several generation- and sex-specific differences in mRNA levels for multiple genes, especially those related to metabolic genes (e.g., F1 EX males had lower mRNA levels of Hk2, Ppard, Ppargc1M-NM-1, Adipoq, and Scd1 than F1 SED males). These results provide preliminary evidence that parental exercise training can influence health-related phenotypes in mouse offspring. We analyzed RNA from 10 males each from exercise and sedentary ancestries over 2 generations of offspring (F1 and F2)
Project description:Quantitative comparison of the protein load of small extracellular vesicles circulating in serum prior and after high intensity interval training.