ABSTRACT
1, 2-Dimethylhydrazine [DMH] enhances lipid peroxidation rate by tumor mitochondria than normal tissue counterpart and causes many disorders in antioxidant system in liver. It also increases the level of enzymes that metabolize toxin in liver and colon. The aim of this study was to evaluate the alteration of liver and its enzymes after DMH injection and evaluate protective effect of cell wall and cytoplasmic fractions of Saccharomyces cereviseae enriched with selenium [Se] on these tissues. Forty eight female rats were prepared and acclimatized to the laboratory conditions for two weeks, and all animals received 1, 2- dimethyl hydrazine chloride [40 mg/kg body weight] twice a week for 4 weeks except healthy control. At first colon carcinoma [aberrant crypt foci] confirmed by light microscope. Then the changes resulting from injection of DMH on liver of animals in initial and advanced stages of colon cancer were examined. In addition, the protective effect of cell wall and cytoplasmic fractions of Selenium-enriched S. cerevisiae were investigated in two phases. First phase in initial stage and second phase in advanced stage of colon cancer were performed respectively. Forty weeks following the first DMH injection, all survived animals were sacrificed. Then, colon and liver removed and exsanguinated by heart puncture. For measuring the levels of enzymes [AST, ALT, and ALP], a commercial kit [Parsazmoon, Iran] and an autoanalyzer [BT 3000 Pluse, Italy] were used. The results showed that subcutaneous injection of DMH increased the ALT, AST, and ALP levels up to 78.5, 161.38, and 275.88 U/L compared to the control, respectively. Moreover, statistical analysis in both phases of experiment revealed that the enzyme levels were decreased in the treated groups in comparison with the DMH-injected group, while the levels of these enzymes were lower in the control group. It should be concluded that administration of cell wall and cytoplasmic fraction prepared from Se-enriched S. cerevisiae could reduce the tissue damages in the livers DMH-injected rats. This beneficial effect would warrant further study on the clinical application of Se-enriched yeast