Conjugated linoleic acid (CLA) prevents age associated skeletal muscle loss in mice by maintaining redox balance during aging

Abstract

Age related skeletal muscle sarcopenia is a major health problem. Currently, there is no safe and effective therapies that selectively increase skeletal muscle mass. Previously, we have shown that CLA maintains higher skeletal muscle mass in mice. This study was designed to elucidate the molecular mechanisms of muscle loss prevention by CLA using 12 mo old C57BL/6 mice fed 10% corn oil (CO) or a diet supplemented with 0.5% c9t11 CLA (CLA 1), t10c12 CLA (CLA 2) or c9t11 CLA+t10c12 CLA (CLA mix) for 6 months. Dual energy X‐ray absorptiometry (DXA) scan was performed at baseline, and end of dietary intervention. CLA 2 and CLA mix groups showed significantly higher muscle mass as compared to CO and CLA 1 groups by DXA and muscle wet weight. Production of muscle mitochondrial ATP, and H2O2 as reactive oxygen species and muscle antioxidant enzymes (catalase and glutathione peroxidase) has been analyzed. Enhanced production of ATP, and antioxidant enzymes accompanied by slight increase in H2O2 level was noted in CLA 2 and CLA mix groups as compared to that of CO and CLA 1 groups. Finally, we have analyzed serum malondialdehyde (MDA) level. The lower level of serum MDA in CLA 2 and CLA mix groups indicate less oxidative stress in these groups. These data suggest that CLA 2 and CLA mix groups may preserve muscle mass by enhancing muscle mitochondrial energy production as well as by maintaining the redox balance during aging. Research support: NIH