Project description:Divergent skeletal muscle phenotypes result from chronic resistance-type versus endurance-type contraction, reflecting the principle of training specificity. However, it is unclear whether there is a common set of genetic factors that influence skeletal muscle adaptation to disuse. Female rats were obtained from out-bred lines selectively bred from high responders to endurance training (HRT) or low responders to endurance training (LRT; n=6/group; generation 19). Both groups underwent 3 d of hindlimb immobilization to induce atrophy of the plantaris and soleus muscles prior to comparison to non-immobilization controls of the same genotype. RNA sequencing was performed to identify Gene Ontology Biological Processes with differential (LRT vs HRT) gene set enrichment. Running distance, determined well in advance of hindlimb immobilization, increased in response to aerobic training in HRT but not LRT. The atrophy response to hindlimb immobilization was exaggerated in LRT versus HRT. There were between-group differences for 140 processes in plantaris muscle and 118 processes in soleus muscle. In conclusion, low responders to aerobic endurance training exhibited exaggerated atrophy, and this was associated with differential gene expression. Thus, our findings suggest that genetic factors that underpin aerobic training maladaptation may also dysregulate the transcriptional activity of biological processes that contribute to adaptation to hindlimb immobilization.
Project description:Divergent skeletal muscle phenotypes result from chronic resistance-type- versus endurance-type contraction, reflecting the principle of training specificity. However, it is unclear whether there is a common set of genetic factors that influence skeletal muscle adaptation to different modes of training. Female rats were obtained from out-bred lines selectively bred from high responders to endurance training (HRT) or low responders to endurance training (LRT; n=6/group; generation 19). Both groups underwent 14 d of synergist ablation to induce functional overload of the plantaris muscle prior to comparison to non-overload controls of the same genotype. RNA sequencing was performed to identify Gene Ontology Biological Processes with differential (LRT vs HRT) gene set enrichment. Running distance, determined well in advance of synergist ablation, increased in response to aerobic training in HRT but not LRT (65 ±26% versus -6 ±18%, respectively, mean ±SD, p<0.0001). The hypertrophy response to functional overload was attenuated in LRT versus HRT (20.1 ±5.6% versus 41.6 ±16.1%, respectively, P = 0.015). There were between-group differences in the magnitude of response of 96 upregulated- and 101 downregulated pathways. A further 27 pathways showed contrasting upregulation or downregulation in LRT versus HRT in response to functional overload. In conclusion, low responders to aerobic endurance training were also low responders for compensatory hypertrophy, and attenuated hypertrophy was associated with differential gene expression. Thus, our findings suggest that genetic factors that underpin aerobic training maladaptation may also dysregulate the transcriptional activity of biological processes that contribute to adaptation to mechanical overload.
Project description:The molecular pathways which are activated and contribute to physiological remodeling of skeletal muscle in response to endurance exercise have not been fully characterized. We previously reported that ~800 gene transcripts are regulated following 6 weeks of supervised endurance training in young sedentary males, referred to as the training responsive transcriptome (TRT). Here we utilized this database together with data on biological variation in muscle adaptation to aerobic endurance training in both humans and a novel out-bred rodent model to study the potential regulatory molecules that coordinate this complex network of genes. We identified three DNA sequences representing RUNX1, SOX9, and PAX3 transcription factor binding sites as over-represented in the TRT. In turn, miRNA profiling indicated that several miRNAs targeting RUNX1, SOX9 and PAX3 were down-regulated by endurance training. The TRT was then examined by contrasting subjects who demonstrated the least vs. the greatest improvement in aerobic capacity (low vs. high responders), and at least 100 of the 800 TRT genes were differentially regulated, thus suggesting regulation of these genes may be important for improving aerobic capacity. In high responders, pro-angiogenic and tissue developmental networks emerged as key candidates for coordinating tissue aerobic adaptation. Beyond RNA level validation there were several DNA variants that associated with VO(2)max trainability in the HERITAGE Family Study but these did not pass conservative Bonferroni adjustment. In addition, in a rat model selected across 10 generations for high aerobic training responsiveness, we found that both the TRT and a homologous subset of the human high responder genes were regulated to a greater degree in high responder rodent skeletal muscle. This analysis provides a comprehensive map of the transcriptomic features important for aerobic exercise-induced improvements in maximal oxygen consumption. This data is from skeletal muscle post 6 weeks of endurance exercise training.
Project description:The molecular pathways which are activated and contribute to physiological remodeling of skeletal muscle in response to endurance exercise have not been fully characterized. We previously reported that ~800 gene transcripts are regulated following 6 weeks of supervised endurance training in young sedentary males, referred to as the training responsive transcriptome (TRT). Here we utilized this database together with data on biological variation in muscle adaptation to aerobic endurance training in both humans and a novel out-bred rodent model to study the potential regulatory molecules that coordinate this complex network of genes. We identified three DNA sequences representing RUNX1, SOX9, and PAX3 transcription factor binding sites as over-represented in the TRT. In turn, miRNA profiling indicated that several miRNAs targeting RUNX1, SOX9 and PAX3 were down-regulated by endurance training. The TRT was then examined by contrasting subjects who demonstrated the least vs. the greatest improvement in aerobic capacity (low vs. high responders), and at least 100 of the 800 TRT genes were differentially regulated, thus suggesting regulation of these genes may be important for improving aerobic capacity. In high responders, pro-angiogenic and tissue developmental networks emerged as key candidates for coordinating tissue aerobic adaptation. Beyond RNA level validation there were several DNA variants that associated with VO(2)max trainability in the HERITAGE Family Study but these did not pass conservative Bonferroni adjustment. In addition, in a rat model selected across 10 generations for high aerobic training responsiveness, we found that both the TRT and a homologous subset of the human high responder genes were regulated to a greater degree in high responder rodent skeletal muscle. This analysis provides a comprehensive map of the transcriptomic features important for aerobic exercise-induced improvements in maximal oxygen consumption.
Project description:The participants performed 8 weeks of superised aerobic endurance exercise. Skeletal muscle biopsise were taken at rest before and after intervention and matched analysis was performed.
Project description:The present analysis was executed to determine the impact of protein supplementation on changes in the muscle transcriptome following prolonged endurance training
Project description:This SuperSeries is composed of the following subset Series: GSE18583: Baseline skeletal muscle gene expression GSE35659: A transcriptional map of the impact of endurance exercise training on skeletal muscle phenotype (resting muscle after endurance training) Refer to individual Series