Immunohistochemical evaluation of chemopreventive effect of hydro-alcoholic extract of garlic (Allium sativum) in N-methyl-N-nitrosourea (NMU) induced rat mammary tumours

Abstract

Consumption of diets rich in vegetables and herbs is often associated with a reduced risk of developing cancer,particularly breast cancer.Many different cultures throughout the world have recognized the potential use of garlic for prevention and treatment of different diseases.The aim of the present study was to evaluate the chemopreventive effect ofhydro-ethanolic extract of Allium sativum(AS)on the expression pattern of biomolecular markers such as, proliferating cell nuclear antigen (PCNA),vascular endothelial growth factor (VEGF), and caspase-3 during N-methyl-N-nitrosourea (NMU) induced mammary carcinogenesis in Wistar rats.The NMU was injected at 50, 80, and 110days of age in both treatment and preventive group. In untreated control animals, 18 numbers of mammary tumours were successfully induced in 6 (50%) rats with average latency period of 85.84±2.47 days. In preventive group, the average latency period was 141.66±4.09 and total four tumours developed in 2 (16.67%) rats. Immunohistochemical analysis revealed over expression of PCNAand VEGF, and decreased expression of caspase-3 in the mammary tissues of NMU treated rats. Oral administration of hydro-ethanolic extract of AS in NMU treated rats significantly down regulated the expression of PCNA, VEGF and up regulated the expression of caspase-3. In conclusion, the hydro-ethanolic extract of AS treatment reduced cellular proliferation, angiogenesis, and induced more apoptosis in NMU induced mammary carcinogenesis in Wistar rats.