Interactive effect of exercise training and growth hormone administration on histopathological and functional assessment of the liver in male Wistar rats

BACKGROUND: Abuse of growth hormone (GH) is expanding in exercising populations due to its lipolytic and anabolic actions. The purpose of this study was to examine the interactive effect of exercise training and GH administration on histopathological and functional assessment in the liver of male Wistar rats. 

METHODS: Forty-eight male Wistar rats were randomly divided into six groups including control + saline group (CS), GH injection group (GI), resistance training + saline group (RS), aerobic training + saline group (AS), resistance training + GH injection group (RG), aerobic training + GH injection group (AG). All groups were injected with either saline or GH 1 h before each training session. RT and AT were performed five days/week for a total of 8-weeks. At the end of the study, blood samples and liver tissue samples were taken to evaluate circulating AST, ALT, and ALP enzymes, as well as albumin protein. Histopathology of liver tissue was performed via qualitative microscopic evaluation. 

RESULTS: Microscopic evaluation of liver tissue did not show any histopathologic changes. All the groups administered with GH showed a significant increase in ALT, ALP, and albumin protein (P<0.05). However, AST enzyme concentrations increased significantly only in the RG group (P=0.022). In addition, neither RS nor the AS groups showed significant AST, ALT, and ALP changes, but serum albumin concentration significantly increased in the AS group (P=0.033). 

CONCLUSIONS: The elevation of liver enzymes showed that GH administration with or without exercise training might cause severe liver damage.