Abstract
BACKGROUND: The chronome (from chronos, time, and nomos, rule; time structure) of lipid peroxidation and anti-oxidant defense mechanisms may relate to the efficacy and management of preventive and curative chronotherapy. PATIENTS AND METHODS: Thirty patients with liver cirrhosis, 25-45 years of age, and 60 age-matched clinically healthy volunteers were synchronized for 1 week with diurnal activity from about 06:00 to about 22:00 and nocturnal rest. Breakfast was around 08:30, lunch around 13:30 and dinner around 20:30. Drugs known to affect the free-radical system were not taken. Blood samples were collected at 6-h intervals for 24 h under standardized, presumably 24-h synchronized conditions. Determinations included plasma lipid peroxides, in the form of malondialdehyde (MDA), blood superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) activities, and serum total protein, albumin, ascorbic acid, and uric acid concentrations. RESULTS: A marked circadian variation was demonstrated for each variable in each group by population-mean cosinor (P < 0.01). In addition to anticipated differences in overall mean value (MESOR), patients differed from healthy volunteers also in terms of their circadian pattern. CONCLUSION: Mapping the broader time structure (chronome) with age and multifrequency rhythm characteristics of antioxidants and pro-oxidants is needed for exploring their putative role as markers in the treatment and management of liver cirrhosis.