This study aims to explore the chemopreventive mechanisms of hydroethanolic extracts from avocado (Persea Americana) in
diethylnitrosamine (DEN)/
2-acetylaminofluorene (2AAF)-induced hepatocarcinogenesis. Chemical induction of hepatocarcinogenesis was induced by
intraperitoneal injection of DEN at 150 mg/kg
body weight (b.w.) twice a week for a fortnight, followed by
oral administration of 2AAF at 20 mg/kg b.w. four times a week for 3 weeks. Rats administered DEN/2AAF were orally treated with hydroethanolic extracts of avocado fruits and seeds at a dose of 50 mg/kg b.w. every other day for 20 weeks. Moreover, rats administered DEN/2AAF and treated with avocado extracts revealed a marked decrease in liver
enzyme activities, total
bilirubin levels, and elevated liver
tumor markers, but revealed an increase in total
protein and
albumin levels. The hepatocytes with hyperchromatic and bile duct
cystadenoma observed in the liver of rats administered DEN/2AAF were reduced due to treatment with avocado extracts. Furthermore, the treatments prevented the elevation of lipid peroxidation levels and ameliorated the lowered
glutathione peroxidase,
glutathione-S-transferase,
superoxide dismutase activities, and
glutathione content in the liver tissues. Also,
antigen Ki-67,
cyclooxygenase-2, and
nuclear factor kappa-B expression levels were decreased, but of the suppressor
proteins p53 and BAX levels were increased in the liver of rats administered DEN/2AAF and treated with avocado extracts. In conclusion, the current results demonstrated that avocado extracts could abate hepatocarcinogenesis in rats administered DEN/2AAF through activation of
antioxidant, anti-inflammatory, and apoptotic properties.