Hepatoprotective role of swimming against arsenic induced oxidative stress in mice

Abstract

Objective: Arsenic is the most prevalent and common environmental contaminant, found in drinking water with varying concentrations. Inorganic arsenic is involved in the generation of reactive oxygen species (ROS). The aim of present study was to determine the activities of antioxidant enzymes in liver of mice, changes with arsenic exposure and to determine whether it is associated with the induction of oxidative stress. Furthermore, we intended to determine whether swimming exercise can modulate the activities of antioxidant enzymes in vivo rendering protection to the liver of mice during arsenic exposure. Methods: Mouse model was established, mice were administrated with two different doses (10 and 20 mg/kg/day) of sodium arsenite. These mice underwent swimming exercise for about 8 weeks regularly. First group was negative control which received distilled water and no exercise. Group 2 and 4 were positive controls in which 10 mg/kg/day and 20 mg/kg/day of sodium arsenite were administered respectively, for 8 weeks. Group 3 and 5 underwent swimming exercise for 60 min daily along with 10 mg/kg/day and 20 mg/kg/day of sodium arsenite for same duration and act as treatment group. Results: Our results revealed that arsenic level was higher (0.13 mg/L) in the liver of mice lacking exercise in comparison to the exercise group (0.04 mg/L). Similarly, Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were found higher in mice lacking swimming exercises showing sodium arsenite had more severe pathological damages in liver as compared to the exercise groups. On the other hand, catalase (2.61 nmol/mg) and glutathione levels (1.25 nmol/mg) and expression of two antioxidant pathway genes i.e. NQO-1 and HO-1 were found elevated in exercise group. Conclusion: This study reveals that swimming alleviate the arsenic induced liver damages in mice through induction of Nrf2 antioxidant pathways. All these findings allowed us to speculate the involvement of swimming exercise which is responsible for hepato-protective activity. Keywords: Sodium arsenite, Swimming exercise, Antioxidants, Oxidative stress, Signaling pathway, Pathological damages