Dose-dependent chemopreventive effects of citronellol in DMBA-induced breast cancer among rats

Breast cancer is one of the most common cancers among women world wide and its incidence is on tremendous increase. The present study is aimed to analyze the dose-dependent chemopreventive efficacy of citronellol on 7,12-dimethylbenz(a)anthracene (DMBA)-induced rat mammary carcinogenesis. The mammary tumor was induced through a single dose of DMBA (25 mg/rat) injected subcutaneously near the mammary gland of rats. In DMBA-injected rats, 100% tumor incidence, increased tumor volume, and tumor burden along with loss of body weight were observed. Biochemical analysis revealed the increased levels of phase I detoxification proteins (cytochrome P450 and b5) and decreased activities of phase II detoxification enzymes (glutathione-S-transferase and glutathione reductase) in hepatic and mammary tissues. The levels of enzymatic and non-enzymatic antioxidants (superoxidedismutase, catalase, glutathione peroxidase, and (GPx) and reduced glutathione) were decreased and lipid peroxidation by-products (thiobarbituric acid reactive substance and lipid hydroperoxide) got increased in plasma and mammary tissues. Oral administration of different doses of citronellol (25, 50, and 100 mg/kg body weight) to DMBA-treated rats for 16 weeks absolutely inhibited the tumor incidence and restored the biochemical parameters near to normal level in 50 and 100 mg doses whereas the histopathological studies also supported the biochemical findings. Hence, the result suggests that the citronellol of 50 mg/kg body weight exerted significant chemopreventive effects and can be considered as a minimum optimum dose in the prevention of mammary carcinogenesis.