Toxicopathological interaction of lead and cadmium and amelioration with N-Acetyl-L-Cysteine

Aim: To investigate the nephrotoxicity induced by the combined exposure of lead (Pb) and cadmium (Cd) and its amelioration with N-acetyl-L-cysteine (NAC). Materials and Methods: To evaluate the nephrotoxicity of Pb and Cd, the present study was taken up with a total of 48 male wistar rats, divided uniformly into eight groups each with 6 rats. Groups I and II were kept as untreated control and NAC control, respectively. Groups III, IV and V served as toxic control groups viz., Pb, Cd and combination of Pb+Cd @ 1000, 300 and 1000+300 ppm, respectively. Whereas groups VI, VII and VIII were co exposed with NAC and served as therapeutic groups (Pb, Cd and combination of Pb+Cd @ 1000, 300 and 1000+300 ppm, respectively and NAC @ 300mg/kg). The experiment was carried out for 3 months and kidney tissues were collected for histopathological and electron microscopic study at the end of the experiment. Results: Histopathological examination of kidney tissue revealed marked alterations and electron microscopic observations also showed marked ultrastructural changes and these changes were more pronounced in Pb and Cd co exposure group (group 5) than the Pb and Cd alone exposed groups (groups 3 and 4), respectively. We also observed a significant (p<0.05) elevation in the serum creatinine levels. Use of the NAC counteracted the all toxic effects by chelating these metals, thereby reducing their accumulation and NAC also demonstrated its antioxidant properties, as judged by a significant reduction in the serum creatinine levels. Conclusion: We conclude that the co-existence of these metals showed a positive pharmacodynamic interaction and significant improvement was noticed after NAC therapy.