Effects of tea polyphenols and vitamine C on Cd-induced nephrotoxicity

  Objective   TP(Tea polyphenols)and Vc(Vitamine C)were given to rats to study the effects on the nephrotoxicity induced by chronic exposure to cadmium.

  Methods   Four groups were used for the study.Three experimental groups were given subcutaneous injection of 1.44 mg/kg CdCl ₂, two of which were pretreated by TP and Vc respectively before the injected of CdCl2, three times each week for 6 weeks.Control group was injection with 0.9% NaCl at the same time.Urinary samples were collected at the end of the 4th and 6th week.NAG activities, protein, and cadmium contents were determined in urine.Kidney and blood were collected 24 h later after the final injection.BUN and MDA in blood and renal cortex were mensuated.

  Results   NAG activities and protein content in urine of TP and Vc groups decreased significantly compared with those of animals given cadmium alone at the end of week 4.After week 6 the pretr eatment of TP and Vc decreased BUN significantly in blood as well as MDA contents of renal cortex and blood.Moreover, TP obviously decreased Cd content in blood and renal cortex, but increased Cd content in urine.

  Conclusion   TP and Vc could protect rats against the toxic effects of Cd on kidney, which may be the result of reducing lipid peroxidation and Cd content.