Effect of β-sitosterol against methyl nitrosourea-induced mammary gland carcinoma in albino rats

Background: The present study was in quested to study the effects of beta-sitosterol on methyl nitrosourea (MNU) induced mammary gland carcinoma in albino wistar rats. Methods: Animals were randomized and divided into four groups of eight animals each. Group I (sham control 1 % CMC in normal saline p.o.); Group II (toxic control, MNU 47 mg/kg, i.v); Group III (MNU 47 mg/kg, i.v + beta-sitosterol, 10 mg/kg, p. o); Group IV (MNU 47 mg/kg, i.v + beta-sitosterol, 20 mg/kg, p. o). Toxicity was induced by single i.v. injection of MNU followed by beta-sitosterol supplementation therapy for 115 days at the dose mentioned above. Results: Treatment with beta-sitosterol evidenced decrease in the alveolar bud and lobule score in the whole mount of the mammary gland. beta-sitosterol exhibited diminishing effect on oxidative stress through synchronizing lipid and enzymatic antioxidant defense. A significant decrease in the saturated and unsaturated fatty acid was evident with the MNU treatment and beta-sitosterol demonstrated a marked effect on it. Pgp 9.5 expression was dose dependently upregulated by beta-sitosterol treatment in comparison to MNU treatment. On the contrary, downregulated NF-kappa B expression was perceived, when beta-sitosterol was concomitantly administered with MNU. Conclusion: beta-sitosterol afforded significant protection against the deleterious effects of MNU.