Vitamin C administration attenuates overload‐induced skeletal muscle hypertrophy in rats. (28th January 2013)

• Record Type: Journal Article
• Authors: Makanae, Y.; Kawada, S.; Sasaki, K.; Nakazato, K.; Ishii, N.
• Is Part Of: Acta physiologica. Volume 208:Number 1(2013:May)
• Page Start: 57
• Page End: 65
• Publication Date: 2013-01-28
• Subjects: adaptation -- antioxidants -- oxidative damage -- reactive oxygen species -- synergist muscle ablation; Physiology -- Periodicals; Physiology -- Research -- Periodicals; 612
• DOI: 10.1111/apha.12042
• Languages: English
• ISSNs: 1748-1708

Abstract

Abstract: Aim: This study aimed to investigate the effects of vitamin C administration on skeletal muscle hypertrophy induced by mechanical overload in rats. Methods: Male Wistar rats were randomly assigned to three groups: (i) sham‐operated group ( n = 8), (ii) placebo‐administered group ( n = 8) and (iii) vitamin C‐administered group ( n = 8). In the placebo‐administered and vitamin C‐administered groups, the gastrocnemius and soleus muscles of the right hindlimb were surgically removed to overload the plantaris muscle. Vitamin C (500 mg kg −1 ) was orally administered to the vitamin C‐administered group once a day for 14 days. Results: Synergist muscle ablation caused significant increases in wet weight and protein concentration of the plantaris muscle in both the placebo‐administered ( P < 0.01) and vitamin C‐administered groups ( P < 0.01) compared with the sham‐operated group (SHA). However, the magnitude of plantaris muscle hypertrophy (expressed as a percentage of the contralateral plantaris muscle) was significantly smaller ( P < 0.01) in the vitamin C‐administered group (141%) than in the placebo‐administered group (PLA) (152%). Compared with the SHA, only the PLA showed higher expressions of phosphorylated p70s6k and Erk1/2 (positive regulators of muscle protein synthesis) and a lower expression of atrogin‐1 (a muscle atrophy marker). Concentrations of vitamin C and oxidative stress markers in the overloaded muscle were similar between the placebo‐administered and vitamin C‐administered groups. Conclusion: Oral vitamin C administration can attenuate overload‐induced skeletal muscle hypertrophy, which may have implications for antioxidant supplementation during exercise training.