Anti-oxidative and anti-inflammatory activities of placental extracts in benzo[a]pyrene-exposed rats

Objective: Placental extracts (PE) have been used for years as a folk remedy in Asian countries. PE mediates alleviation of menopausal symptoms, wound healing, liver regeneration and anti-inflammatory responses. In this study, we evaluated the protective effects of PE on rats exposed to benzo[a]pyrene (BaP). Methods: The composition of amino acids, sugars and fatty acids in PE was analyzed. The effect of PE on DNA damage was determined by Comet assay, and oxidative damage was determined by measuring the activity of superoxide dismutase and the levels of lipid peroxidation. The effect of PE on cytokines and immunoglobulin levels was determined by western blot analysis. Results: Exposure of rats to BaP significantly increased the Olive Tailmoments compared to controls, while pre-treatment with PE composed of diverse amino acids, monosaccharides and fatty acids significantly decreased the Olive Tailmoments induced by BaP. In addition, oxidative stress induced by BaP was attenuated by pre-treatment with PE. Furthermore, PE pre-treatment significantly decreased the levels of pro-inflammatory cytokines such as TNF-α, IL-1β, and IL-6. Conclusion: Pre-treatment of rats with PE significantly attenuates oxidative damage and immunotoxicity induced by BaP. These findings suggest the further studies regarding the protective effects of PE against environmental toxicants in humans.