Aim: 

To test the effects of programmed exercise on a variety of hepatic indices in the adult obese Zucker (OZ)-rat to derive possible beneficial effects on prevention of risk factors associated with the metabolic syndrome and analyze differential responses of sedentary and chronically exercised OZ-rats to a single exercise bout.

Methods: 

Four groups of 8 OZ-rats each were used (S-, S+, E-, E+). Two of them (E-, E+) adhered to an exercise programme of treadmill-running (EPTR) of 3-month duration while the other two (S-, S+) did not. One group of each (S-, E-) was sacrificed 3 days after the last training session while the other (S+, E+) performed an exercise bout immediately before sacrifice. Hepatic glycogen, protein glycation (as hydroxymethyl furfural), oxidative stress (free and protein-bound TBARS, reactive protein-carbonyls), antioxidant defence (Cu/Zn- and Mn-SOD) and carboxylase levels were analyzed.

Results: 

Adherence to the EPTR reduced body and liver weight. At the end of the EPTR hepatic glycogen did not decrease significantly following an exercise bout while in sedentary did. Free lipid peroxidation products (measured as TBARS) increased in E+. Protein-bound TBARS were lower in E than in S and the opposite was observed for glycated proteins. Reactive protein carbonyls showed a trend towards increasing in response to both chronic and acute exercise. No significant up-regulation of either of the SODs was observed.

Conclusion: 

Despite data showing beneficial effects for the liver of adhering to the EPTR, lipid and protein oxidation indices and levels of SODs did not indicate a significant protective effect of chronic exercise on adult OZ-rats.

Funded by the "Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica 2004-2007, Acción Estratégica sobre Deporte y Actividad Física (DEP2006-56187-C04)" from the Ministry of Education and Science, Spain.