Researchers here compare the effects of calorie restriction and dietary resveratrol on the pace of sarcopenia, the age-related loss of muscle mass and strength. What I take away from this is that calorie restriction produces meaningful results on this front, albeit modest in comparison to what we'd like to see, and resveratrol doesn't.
Aging is associated with a loss in muscle known as sarcopenia that is partially attributed to apoptosis. In aging rodents, caloric restriction (CR) increases health and longevity by improving mitochondrial function and the polyphenol resveratrol (RSV) has been reported to have similar benefits. In the present study, we investigated the potential efficacy of using short-term (6 weeks) CR (20%), RSV (50 mg/kg/day), or combined CR+RSV (20% CR and 50 mg/kg/day RSV), initiated at late-life (27 months) to protect muscle against sarcopenia by altering mitochondrial function, biogenesis, content, and apoptotic signaling in both glycolytic white and oxidative red gastrocnemius muscle (WG and RG, respectively) of male Fischer 344 x Brown Norway rats.
CR but not RSV attenuated the age-associated loss of muscle mass in both mixed gastrocnemius and soleus muscle, while combined treatment (CR+RSV) paradigms showed a protective effect in the soleus and plantaris muscle. Sirt1 protein content was increased by 2.6-fold in WG but not RG muscle with RSV treatment, while CR or CR+RSV had no effect. PGC-1α levels were higher (2-fold) in the WG from CR-treated animals when compared to ad-libitum (AL) animals but no differences were observed in the RG with any treatment.
These data suggest that short-term moderate CR, RSV, or CR+RSV tended to modestly alter key mitochondrial regulatory and apoptotic signaling pathways in glycolytic muscle and this might contribute to the moderate protective effects against aging-induced muscle loss observed in this study.