Protective effect of menthol against diethylnitrosamine-induced hepatocellular carcinoma in mice by downregulating CTNNB۱ and HIF-۱α

Objective: This study examined the impact of menthol, a natural monoterpene, on diethylnitrosamine (DEN)-induced molecular and histopathological changes in the livers of male mice.Materials and Methods: Forty male mice were divided into four groups: Control, Menthol (M), DEN, and DEN-M. The DEN and DEN-M groups received an intraperitoneal injection of DEN (۲۵ mg/kg) at the age of ۱۴ days. The M and DEN-M groups were also given menthol (۵۰ mg/kg, three times a week for six months) via gavage. The expression of genes related to liver carcinoma was analyzed using real-time PCR. Subsequently, the liver tissue was microscopically examined following staining with hematoxylin-eosin.Results: After one month, menthol reduced the infiltration of inflammatory cells in the liver tissue of mice injected with DEN. It also prevented the increase in the expression of alpha-fetoprotein (AFP) (p<۰.۰۰۱), programmed cell death ۶ (p<۰.۰۵), hypoxia-inducible factor-۱ alpha (HIF-۱α) (p<۰.۰۰۱), and vascular endothelial growth factor (VEGF) (p<۰.۰۰۱) in DEN-M animals compared with DEN group. After six months of session, the expression of AFP (p<۰.۰۵), HIF-۱α (p<۰.۰۵), secreted frizzled-related protein ۱ (p<۰.۰۰۱), and catenin beta ۱ (p<۰.۰۱) was lower in group DEN-M compared with group DEN. Menthol also partially prevented DEN-induced various histopathological changes in the liver after six months of treatment.Conclusion: We concluded that menthol inhibits Wnt signaling and suppresses the expression of HIF-۱α and VEGF in the liver of DEN-injected mice. It is probably a suitable option for the prevention and treatment of hepatocellular carcinoma.

Keywords:

Monoterpenes , Wnt signaling pathway , Angiogenesis , Alpha-fetoprotein , Liver