Mitochondrial damage has implicated a major contributor for ageing process. In the present study, we measured mitochondrial membrane swelling, mitochondrial respiration (state 3 and 4) by using oxygen electrode in skeletal muscle of young (3-4 months old) and aged rats (above 24 months old) with supplementation of L: -carnitine and DL: -alpha-lipoic acid. Our results shows that the mitochondrial membrane swelling and state 4 respiration were increased more in skeletal muscle mitochondria of aged rats than in young control rats, whereas the state 3 respiration, respiratory control ratio (RCR) and ADP:O ratio decreased more in aged rats than in young rats. After supplementation of carnitine and lipoic acid to aged rats for 30 days, the state 3 respiration and RCR were increased, whereas the state 4 and mitochondrial membrane swelling were decreased to near normal rats. From our results, we conclude that combined supplementation of carnitine and lipoic acids to aged rats increases the skeletal muscle mitochondrial respiration, thereby increasing the level of ATP.

The exposure of biological system to various conditions of oxidative stress is the major contributor for aging process. Oxidative stress in turn increases the cellular levels of oxidatively modified proteins, lipids and nucleic acids resulting in a loss of physical activity and metabolic integrity. In this study, we evaluated the role of L-carnitine and DL-alpha-lipoic acid in minimizing oxidant generation and macromolecular damage in skeletal muscle of aged rats. We found that the oxidant generation was increased in aged rat skeletal muscle when compared to young rats. There was a simultaneous increase in the levels of lipid peroxidation, protein carbonyl content and DNA strand breaks in aged rat skeletal muscle. Administration of L-carnitine (300 mg/kg body wt/day) and DL-alpha-lipoic acid (100 mg/kg body wt/day) to aged rats for 30 days, decreased the oxidant generation, lipid peroxidation, protein carbonylation and DNA strand breaks. We concluded that co-administration of carnitine and lipoic acid to aged rats has the potential to prevent oxidative stress mediated macromolecular damage in skeletal muscle of aged rats by their putative role as efficient antioxidants.

Brain aging has become an area of intense research and a subject of much speculation fueled largely from the widely recognized fact that age is the biggest risk factor in most neurodegenerative diseases and age-related increase of reactive oxygen species is particularly detrimental to postmitotic tissues. In the present study, we have evaluated the possible role of glutathione monoester (GME), when administered intraperitoneally (12mg/kg body weight) for 20 days on age-associated changes in the levels of lipofuscin, Na+K+, Mg2+, Ca2+ ATPase activities and intracellular calcium levels in discrete brain regions of young and aged male albino Wistar rats. An age-associated increase in lipofuscin, intracellular calcium in cortex, striatum and hippocampus was observed and contradictorily, a decrease in the activities of membrane-bound enzyme activities was also observed. Supplementation of GME brought these changes to near normalcy. Thus, GME improves neuronal antioxidant status, thereby effectively attenuating any putative increase in oxidative stress with age.