Protective effects of black Iranian tea on cadmium- induced hepatotoxicity in rats

Useful effects of black tea in treatment of many diseases have been shown . the protective effects of tea are possibly related to its antioxidant properties or its inhibition of lipid oxidation. The aim of the present study was to investigate hepatoprotective effects of black Iranian tea on cadmium(cd)-induced hepatotoxicity .For this purpose 30 male wistar rats were randomly divided to six study groups including 1-negative control, 2-treatment control (received 10% black tea brewed drink (BTBD)),3-positive control which received cd(5 mg/kg body weight (bw.)/day) and 4 to 6-treatment groups in which BTBD was administered orally (2,5 and 10%) with oral cd(5mg/kg bw./day). The rats were sacrificed after 4 weeks and blood samples were collected to assess liver biomarkers. liver samples were fixed in buffered formalin solution . They were then conventionally embedded in paraffin and stained with Hematoxilin - Eosin for pathology studies as well. In positive control group, activities of alanine transaminas (ALT), aspartate transaminase(AST) and alkaline phosphatase (ALP) significantly increased in compare with negative control group. Granular degeneration, chromatin and nucleus concentration and necrosis were evidenced in pathological study of the liver sections of this group. On the other hand, 5 and 10% BTBD administration significantly prevented ALT,AST and ALP increasing activity. Pathological study confirmed the latter serological results. Whereas, 2% BTBD administration didnt have any significant protection. in conclusion, our results suggest that daily black tea drinking may prevent cd-induced hepatic lesions.