Endurance Training With Curcumin Treatment Regulated Mitochondrial Biogenesis In Skeletal Muscle Through Sirt1-mediated Signaling Pathway

PURPOSE: Mitochondrial biogenesis in response to exercise is reliant on adaptive changes of PGC-1α (Jager et al. 2007). Sirtuin 1 (SIRT1)-mediated PGC-1α deacetylation is potentially key signal for activating mitochondrial biogenesis (Rodgers et al. 2008). Activation of SIRT1, eg. by resveratrol, is beneficial for regulation of mitochondrial biogenesis (Menzies et al. 2013). Polyphenol curcumin, derived from the rhizomes Curcuma longa L is a natural antioxidant exhibiting a variety of pharmacological activities and therapeutic properties. However, it remains unknown the effect of curcumin and underlying mechanism on skeletal muscle for regulation of mitochondrial biogenesis. The purpose of the present study was to examine the effects of endurance training (eTR) and curcumin treatment on phoshorylation AMPK, NAD+/NADH ratio, deacetylation PGC-1α and CS enzyme activity in rat skeletal muscle METHODS: 10-week old male Wistar rats were randomized into group of eTR and non eTR. The eTR regimen consisted of swimming for 2 hours/day for 24 days. In addition, low dose (50 mg/kg-BW/day) or high dose (100 mg/kg-BW/day) of curcumin dissolved in DMSO and injected into intraperitoneal for 28 days to the groups with or without eTR to test the effect of curcumin per se and combined effect of curcumin with eTR. Skeletal muscle (m. gastrocnemius ) was removed from rats 1 hours after the final treatment. The western blotting (WB), NAD+/NADH assay, immunoprecipitation of PGC-1α and CS enzyme activity assessed the presence and activity of proteins. RESULTS: The eTR with high dose of curcumin increased phosphorylation AMPK (∼0.5 fold, p<0.05), NAD+/NADH ratio (+64,8%, p<0.05), deacetylation PGC-1α (∼1.5 fold, p<0.05) and CS activity (+31,65%, p<0.05) in m. gastrocnemius compared with the only eTR group. CONCLUSIONS: The present results suggested that curcumin treatment with eTR regulated mitochondria biogenesis in skeletal muscle through SIRT1-mediated signaling pathway.