Evaluation of Glutathione Bioactivity on Toxoplasma Gondii in BALB/c Mice Post Impact of Selenium and Calcium Supplementation.

Abstract

Studies have shown that selenium is an essential component of glutathione as an important antioxidant to reduce oxidative stress and inhibit intracellular parasites' growth. In contrast, calcium in the cytosol of such parasites plays a key role in the entry of the parasite into the host cell and its primary motility. The present study was designed to evaluate and compare glutathione peroxidase bioactivity effects post administration of selenium and calcium in BALB/c mice infected by Toxoplasma gondii. Sixty BALB/c mice susceptible to T. gondii were randomly divided into twelve groups of case and control groups. There were six control groups including two positive controls infected only with the parasites either 104 or 5×104, non-infected and untreated groups. Treated controls received only calcium, selenium, or both respectively. Case groups were infected with 104 or 5×104 parasites. While each set of three case groups separately received minerals alone or together. Mice were orally fed with 200 μg selenium, 50 μg calcium or their combination for 7 days. Mice were infected by parasite's tachyzoites. Sera of mice were kept and the peritoneal macrophages were isolated for counting tachyzoites during infection. The results showed that selenium unlike calcium was significantly effective in reducing Toxoplasma tachyzoites compared to control groups. Moreover, glutathione peroxidase [GPX] activity was elevated in mice treated with selenium and vice versa decreased in mice treated with calcium. Administration of selenium unlike calcium reduced Toxoplasma tachyzoites proliferation by elevating bioactivity of selenium-dependent detoxification enzyme, GPX.