Pretreatment Effects of Regular Aerobic Training on the IGF System and Hepatotoxicity Induced by Doxorubicin in Rats

Aims: To examine the pretreatment effects of regular aerobic training on the IGF system (IGF-I, IGFBP-3 and IGF/IGFBP) and doxorubicin(DOX) induced hepatotoxicity in rats. Materials and Methods: Forty-eight male rats were divided into groups:(1) control+placebo (2) $control+DOX_{10}mg{\cdot}kg^{-1}$ (3) $control+DOX_{20}mg{\cdot}kg^{-1}$ (4) training+placebo (5) $training+DOX_{10}mg{\cdot}kg^{-1}$ (6) $training+DOX_{20}mg{\cdot}kg^{-1}$. Hepatotoxicity was induced by DOX with dosages of 10 and 20 $mg{\cdot}kg^{-1}$. The rats in groups 4, 5 and 6 performed treadmill running of 25-54 min/day and 15-20 m/min, 5 days/wk for 6 wks. At the end of the aerobic training protocol, rats in the 1 and 4 groups, in the 2 and 5 groups and in the 3 and 6 groups received saline solution, $DOX_{10}mg{\cdot}kg^{-1}$ and $DOX_{20}mg{\cdot}kg^{-1}$, respectively. Results: Administration of $DOX_{20}mg{\cdot}kg^{-1}$ caused a significant increase in IGF-1 and IGF-1/IGFBP-3, an insignificant decrease in IGFBP-3, as compared to the control+placebo group. However, after six weeks of aerobic training and DOX treatment with $10mg{\cdot}kg^{-1}$ and or/ $20mg{\cdot}kg^{-1}$ an insignificant decrease in IGF-1, an insignificant increase in IGFBP-3 and a significant decrease in IGF-1/IGFBP-3 were detected, in comparison to $C+DOX_{10}$ and $C+DOX_{20}$. Conclusions: Hepatotoxicity of doxorubicin is dose-dependent and pretreatment with regular aerobic training may improve DOX-induced hepatotoxicity by up-regulation of IGFBP3.