Objective: To investigate the effects of 2(3)-tert-4-hydroxyanisole (BHA) on protection against synergistic hepatocarcinogenesis of aflatoxin B(1) (AFB(1)) and hepatitis B virus (HBV) expression in HBV large envelope transgenic mice.
Methods: Protective effects of dietary antioxidant BHA on life span was observed in 49 cases of HBV transgenic mice and 48 cases of non-transgenic mice by determinations of enzyme activities and liver MDA, and by direct detection of liver oxidative free radicals (OFR) using electron spin resonance (ESR).
Results: In the HBV transgenic mice which exposed to AFB1, the incidence of hepatocellular adenoma was 17% (2/12), but no carcinoma was found in BHA group. In the regular diet group, that was greater with 67% (6/9) of adenoma and 22% (2/9) of carcinoma. BHA could decrease significantly the concentrations of liver MDA and OFR, compared with those with regular diet. The activities of quinone reductase and glutathione S-transferase in liver cytosols increased by 3 - 7 times, as in the controls, in response to BHA.
Conclusions: Addition of BHA to the diet resulted in significantly elevation of phase II enzyme activities in liver. BHA could directly eliminate liver OFR and inhibit growth of hepatocellular altered foci. These actions may effectively put off hepatocellular carcinogenesis in mice.