Objectives To investigate the impact of acute energetic stress(acute HIIE and fasting)on ERRγ,PPARβ,NR1D1,NR4A1,and TFEB in human skeletal muscle.Methods The current study performed secondary analyses using muscle b...Objectives To investigate the impact of acute energetic stress(acute HIIE and fasting)on ERRγ,PPARβ,NR1D1,NR4A1,and TFEB in human skeletal muscle.Methods The current study performed secondary analyses using muscle biopsy samples from two previously published studies:study 1)leg muscle biopsies from nine men and eight women were obtained pre and 3 h following acute high-intensity interval cycling exercise(HIIE);study 2)leg muscle biopsies were obtained from nine men pre-,during,and post-an 8 h fast with or without 2 h of arm ergometer exercise.RT-PCR was performed on samples from each study to determine the mRNA expression of ERRγ,PPARβ,NR1D1,NR4A1,and TFEB.Additionally,we retrieved data from meta-analyzed human muscle gene expression using the publicly available database MetaMex.Results PGC-1α(p<0.01,d=1.98)and NR4A1(p<0.01,d=1.36)mRNA expression significantly increased while TFEB(p≤0.05,d=0.70)decreased following HIIE.Significant decreases in NR4A1 and NR1D1 mRNA expression were observed following an 8 h fast.Our MetaMex analyses revealed significant increases(p<0.05)in PGC-1αand NR4A1 expression following aerobic and resistance exercise,and in PPARβexpression following resistance exercise.Conclusions Our data indicate that acute HIIE stimulates increases in NR4A1 and PGC-1αand decreases in TFEB mRNA expression in human skeletal muscle.Additionally,a short term(8 h)fast reduced the mRNA expression of the transcriptional regulators NR4A1 and NR1D1–potentially as a mechanism of decreasing mitochondrial biogenesis to reduce energy expenditure during a period of restricted energy availability.展开更多
基金supported by Brendon Gurd’s Discovery Grant from NSERC.
文摘Objectives To investigate the impact of acute energetic stress(acute HIIE and fasting)on ERRγ,PPARβ,NR1D1,NR4A1,and TFEB in human skeletal muscle.Methods The current study performed secondary analyses using muscle biopsy samples from two previously published studies:study 1)leg muscle biopsies from nine men and eight women were obtained pre and 3 h following acute high-intensity interval cycling exercise(HIIE);study 2)leg muscle biopsies were obtained from nine men pre-,during,and post-an 8 h fast with or without 2 h of arm ergometer exercise.RT-PCR was performed on samples from each study to determine the mRNA expression of ERRγ,PPARβ,NR1D1,NR4A1,and TFEB.Additionally,we retrieved data from meta-analyzed human muscle gene expression using the publicly available database MetaMex.Results PGC-1α(p<0.01,d=1.98)and NR4A1(p<0.01,d=1.36)mRNA expression significantly increased while TFEB(p≤0.05,d=0.70)decreased following HIIE.Significant decreases in NR4A1 and NR1D1 mRNA expression were observed following an 8 h fast.Our MetaMex analyses revealed significant increases(p<0.05)in PGC-1αand NR4A1 expression following aerobic and resistance exercise,and in PPARβexpression following resistance exercise.Conclusions Our data indicate that acute HIIE stimulates increases in NR4A1 and PGC-1αand decreases in TFEB mRNA expression in human skeletal muscle.Additionally,a short term(8 h)fast reduced the mRNA expression of the transcriptional regulators NR4A1 and NR1D1–potentially as a mechanism of decreasing mitochondrial biogenesis to reduce energy expenditure during a period of restricted energy availability.
