The Effects Of Blood Flow Restriction On Mitochondrial Gene Expression

Blood flow restriction exercise has been shown to enhance mitochondrial adaptations; however, the mechanisms for this response are still unclear. PURPOSE: To determine the changes in expression for genes associated with mitochondrial turnover in skeletal muscle following blood flow restriction exercise. METHODS: 23 healthy, untrained college-aged (age = 21.3 ± 2.4) males (n = 12) and females (n = 11) were randomly assigned into either a low-intensity blood flow restriction group (i.e., 30% 1-repetition maximum, n = 12, BFR) or a high-intensity group (i.e., 80% 1-repetition maximum, n = 12, HI). All subjects completed leg extensions three times per week, for six weeks. Muscle biopsies of the vastus lateralis were obtained prior to and following the exercise intervention. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed for OPA1, SIRT1, PINK1, and PGC-1ɑ, with B2M as the housekeeping gene. Gene expression data were normalized using the 2-ΔΔCt method and t-test assuming unequal variance. RESULTS: There were no significant differences in mean fold change of gene expression for OPA1 (BFR = -0.06; HI = 0.14; 95% CI: 0.09 ± 0.23), SIRT1 (BFR = 0.01; HI = 0.04; 95% CI: 0.03 ± 0.03), PINK1 (BFR = -0.15; HI = 0.13; 95% CI: -0.04 ± 0.32), and PGC-1ɑ (BFR = -0.08; HI = -0.11; 95% CI: -0.09 ± 0.02). CONCLUSION: Six weeks of blood flow restriction exercise did not alter the expression of the genes associated with mitochondrial turnover in previously untrained, college-aged males and females. FUNDING: Partially supported by NSCA Graduate Research Grant - Master’s Level (TR).