Assessment of Oxidative Stress Indices in Tissues of Cadmium-challenged Female Wistar Rats Treated with Combined Ethanolic Leaf Extract of Manihot esculenta and Citrus sinensis

Abstract

This research assessed the oxidative stress indices in tissues of cadmium-challenged female Wistar rats treated with combined ethanolic leaf extract of Manihot esculenta and Citrus sinensis. Eighteen female rats (150±20g) were divided put into three (3) groups:  Group 1 (received feed and water only); Group 2 (received single dose of cadmium, 30mg/kg body weight at the start of the experiment) and Group 3 (received cadmium as in group 2 above and 200mg/kg body weight of combined extract of orange and cassava leaf, daily for two weeks). Cadmium load in the tissues of the rats were analyzed using AAS after acid digestion and oxidative stress indices were analyzed using standard procedures. Data obtained showed that the cadmium tissue load (?̅±SD, μg/g tissue) were 0.005±0.0007 (liver), 0.007±0.0004 (kidney); 55.4±5.2 (liver), 28.3±4.6 (kidney); and 13.6±2.3 (liver), 20.7±2.5 (kidney) for Groups 1, 2 and 3 respectively. There was a higher concentration of Cd in the liver and kidney of rats exposed to Cd alone (Group 2) compared to the control (Group 1) and Cd-challenged rats treated with combined leaf extract of Manihot esculenta and Citrus sinensis (Group 3).  Exposure to Cd alone caused significant (p<0.05) increase in lipid peroxidation and glutathione peroxidase in the liver and kidney compared to the control. Conversely, the administration of Cd alone to rats caused significant (p<0.05) reduction in the level of glutathione and the activities of superoxide dismutase and catalase compared to the control in both tissues. Significant amelioration was witnessed in all the parameters in Cd-challenged rats treated with the extract compared to rats challenged with Cd alone. The results show that Cd-induced oxidative stress can be countered effectively by combined leaf extract of Manihot esculenta and Citrus sinensis which is rich in antioxidant molecules.