Influence of aging on the circadian patterns of thiobarbituric acid reactive substances and antioxidants in Wistar rats

Advanced aging is characterized by modification of circadian rhythms of physiological, biochemical and endocrine variables. Oxidative stress has been implicated to play a major role in aging and age-related diseases. In the present study, 24h rhythms of lipid peroxidation products (thiobarbituric acid reactive substances, TBARS) and antioxidants such as reduced glutathione (GSH), superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) were investigated in young, middle aged and old rats. Aging processes were found to advance TBARS and to delay GSH, catalase, SOD and Gpx acrophases. Amplitude, 'r' and mesor values of these rhythms (increased mesor of TBARS associated with decreased antioxidant activities) were found during aging processes. Furthermore, this study indicates the necessity to perform more research to reveal the temporal interplay between the central biological clock (SCN), biochemical changes and aging processes.