Ameliorative Effect of Zinc and Vitamin E on Cadmium-Induced Brain Tissues Oxidative Stress

Abstract

BACKGROUND/AIM:Cadmium chloride (CdCl₂) is a heavy metal of cadmium halide in the form of colourless crystals, soluble in water, methanol and ethanol. It constitutes environmental pollution due to its widespread use in industry throughout the world.

It is in the group of metals that are believed to have no established biological functions and are therefore considered as non-essential metals, yet they find their way into the body system and sometimes alter the course of some processes of the body system. The current study investigates the effect of cadmium chloride on oxidative stress level, and also the effect of zinc and vitamin E on the oxidative stress levels of cadmium chloride-exposed CD1 mice. METHOD: A total number of 24 adult mice were used for the study. They were randomly assigned into four groups (n=6). Group A animals served as control. Group B animals were exposed to CdCl₂ (20 mg/kg body weight, each). Group C animals were exposed to CdCl₂ (20 mg/kg body weight, each) and also treated with zinc at 10mg/kg/day, while Group D animals were also exposed to CdCl₂ (20 mg/kg body weight, each) and treated with Vit E at 10mg/kg day. The experiment lasted for 21 days after which brain tissues form all 24 mice were harvested and oxidative stress biomarkers such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and malondialdehyde (MDA) were assayed. RESULTS: SOD concentration was significantly lower (p>0.5) in the CdCl₂ treated group compared to control. There was significant increase (p<0.05) in SOD in both CdCl₂ + Zn and CdCl₂+ Vit E groups compared to CdCl₂ treated group.. There was a significant decrease (p<0.05) in mean catalase concentration in CdCl₂ treated group compared to control. The catalase concentration in CdCl₂ + Zn and CdCl₂ + Vit E treated groups were significantly higher (p<0.05) compared to CdCl₂ group. GPx concentration was significantly lower (p<0.05) in CdCl₂compared to control. The GPx concentration in both CdCl₂ + Zn and CdCl₂+ vit E treated groups were significantly higher (p<0.05) compared to CdCl₂. Malondialdehyde concentration in CdCl₂ treated group was significantly higher (p<0.05) compared to control group. Its concentration in CdCl₂ + Zinc and CdCl₂ + Vit E treated groups were significantly lower (p<0.05) compared to the CdCl₂ induced oxidative stress effect. CONCLUSION:Cadmium chlorideinduces oxidative stress. But zinc and vitamin E which are non-enzymatic antioxidants reverse this effect, thus attention needs to be paid to the level of exposure to cadmium containing compound. Also, zinc and vitamin E are anti-oxidants that ameliorate this oxidative stress effect where it occurs.