Effect of exercise training on antioxidant enzymes and cardiotoxicity of doxorubicin

Abstract

The purpose of this study was to correlate the exercise-induced changes of oxidant stress enzymes with possible modification of the response to the putative oxidant stressor doxorubicin. Enzymatic and histological changes were studied in mice placed on a 21-wk swim training program (1 h/day, 5 days/wk) with and without anthracycline administration. Doxorubicin (4 mg/kg) was administered intravenously through a tail vein on 10 separate days over a 7-wk period (twice weekly during weeks 10, 11, 14, 15, and 16). Blood, liver, and heart levels of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GP) were measured following the 9th and 21st wk. Myocardial histomorphological observations were made by light microscopy after 21 wk. Following 9 wk of training swim-trained animals had significantly elevated levels of CAT, SOD, and GP in blood, as well as elevated GP in liver. After 21 wk, trained animals, regardless of drug status, had elevated blood CAT and SOD activity and increased liver CAT and GP. Training also produced increases in blood GP, liver SOD, and heart CAT; however, in conjunction with doxorubicin these changes were not seen. The degree of cardiotoxicity was significantly greater in the sedentary drug-treated animals than in the swim-trained drug-treated animals. The results suggest a correlation between antioxidant enzyme levels in blood and liver and the degree of damage caused by an anthracycline drug. It was concluded that exercise ameliorates severe toxic damage caused by doxorubicin administration, possibly by increasing enzymes that combat free radical damage.

Moderate endurance training prevents doxorubicin-induced in vivo mitochondriopathy and reduces the development of cardiac apoptosis

“…Previous studies have shown that endurance training attenuates DOX-induced cardiac damage, diminishing the increased biochemical and morphological signs of toxicity induced by in vivo DOX treatment (2,26). However, no data are available concerning the cross-tolerance effect of moderate endurance training on DOX-induced mitochondrial malfunction.…”

Exercise Preconditioning Provides Long-Term Protection Against Early Chronic Doxorubicin Cardiotoxicity

“…Exercise training is one such intervention that shows promise in combating multiple aspects of DOX-induced cardiotoxicity by improving antioxidant status, 28 attenuating apoptotic pathways, 29 and preserving contractile protein expression. 21 In addition, our laboratory has reported that long-term exercise preconditioning protected against earlyonset DOX cardiotoxicity up to 10 days following treatment.…”

Effects of Resistance Training Accompanied by Sustanon Abuse on Hepatotoxicity in Rats with and without Training Experience

“…Results from previous studies analyzing the response of liver antioxidants activity to exercise training are disparate. Increases [23][24][25], and decreases in this parameter have been described [26]. Nevertheless, most authors have reported absence of variations [27,28].…”