The effect of pentoxifylline on malathion-induced mitochondrial damage in rat liver

Malathion is one of the toxic organophosphorus insecticides (OPIs). OPIs induce oxidative stress in various tissues through the generation of free radicals and alteration in antioxidant system. This study was aimed to investigate the possible protective effects of pentoxifylline (PTX) as a phosphodiesterase-5 inhibitor on malathion-induced oxidative damage to rat liver mitochondria. In this experimental study، 20 male Wistar rats weighing 200-250 g were randomly assigned to 4 groups. The first group received normal saline and the second group with malathion (200 mg/kg/day). The third group received pentoxifylline (50 mg/kg/day) alone and the forth group with pentoxifylline (50 mg/kg/day) and malathion in combination. After two weeks of treatment، whole liver tissue، and liver mitochondria were isolated. The activity of antioxidant enzymes such as catalase (CAT) and superoxide dismutase (SOD) was measured. The extents of cellular lipid peroxidation (LPO) and the viability were determined in liver and liver mitochondria. Data were analyzed using analysis of variance (ANOVA) and Tukey test in SPSS software. The activity of SOD enzyme decreased significantly in the group received malathion and pentoxifylline compared to the group received malathion alone (P<0. 05). Malathion increased significantly the activity of CAT enzyme in liver (P<0. 05). The groups received malathion and pentoxifylline in combination and alone showed a significant decrease in the activity of CAT enzyme in liver (P<0. 05). The viability determined in mitochondria in the groups received malathion and pentoxifylline in combination and alone showed a significant increase (P<0. 05). It is concluded that the mechanism of toxicity of malathion in liver can be recovered by antioxidants included PTX.