EFFECTS OF SELENIUM ON THE IMMUNE AND OXIDATIVE RESPONSE IN LEAD AND CADMIUM EXPOSURE. EXPERIMENTAL STUDIES

Didi Surcel*, Victoria Coldea, Zoe Anca, Stela Ramboiu, I. Chereji Departament of Occupational Medicine, Institute of Public Health, Cluj‑Napoca, 3400 Cluj‑Napoca, Romania)

In industrial environment particularly in nonferrous metallurgic areas, humans have exposed to the simultaneous actions of many metals. It is well known that the main biochemical mechanism of heavy metals is their interaction with reactive groups of many enzymes and heavy metal‑ induced toxicity to specific organs includes the immune system. Current concept on selenium (Se) has been focused on its immunomodulatory and antioxidant effects. In the present study we try to detect the in vivo effects of lead and cadmium (Cd), administered alone and associated with Se, on some immunologic parameters. The experiment was performed on Wistar rats divided in 8 groups : 1. Control ‑ group; 2. Se‑treated group; 3.Leadtreated group; 4. Cd‑treated group; 5. Lead + Cd ‑treated group; 6. Lead + Se‑treated group; 7. Cd + Se‑ treated group; 8. Lead + Cd + Se ‑treated group. Lead was administered in solution of lead acetate, 200 mg/kg b.w. at regular intervals for 90 days. Cadmium, 30 ppm, was administered at regular intervals for 90 days. The animals were given daily selenium 1 ppm for 90 days. The following parameters were assessed : 1. 3Hthymidine incorporation; 2. IL‑I assay; 3. TNF assay; 4. Chemiluminiscence assay; 5. Lipid Peroxides. Our results point out that lead and Cd interfere with immune reactions, more important in their associated administration. Selenium administration may be a protective agent ,demonstrated by the partial reversibility of the lead and Cd induced altered immune reactions.