Beneficial effects of silymarin against nitric oxide-induced oxidative stress on cell characteristics of bovine oviduct epithelial cell and developmental ability of bovine IVF embryos

摘要

The antioxidative effects of silymarin were examined against nitric oxide-induced oxidative stress on cell characteristics of bovine oviduct epithelial cell (BOEC) and developmental rates of bovine in vitro fertilisation (IVF ) embryos. The cell viability and morphology in BOEC which were treated with sodium nitroprusside (SNP) declined, as concentrations of SNP increase. The additions of silymarin 50, 100 and 200 ???μM into SNP 1000 ???μM increased the cell viability inhibited by SNP 1000 ???μM alone, but addition of silymarin 500 ???μM into SNP 1000 ???μM group did not recover the inhibitory effect of SNP 1000 ???μM ( p< 0.05). The levels of malondialdehyde (MDA), as the indicator of lipid peroxidation (LPO) in the treatments of SNPs increased with dose-dependant manners ( p< 0.05), whereas additions of silymarin 50, 100 and 200 ???μM into SNP 1000 ???μM significantly decreased MDA levels by 1.6, 1.4 and 1.3 folds of control ( p< 0.05). Antioxidant and Bcl-2 genes were expressed in control or SNP 1000 ???μM plus silymarin 200 ???μM treatment group, whereas pro-apoptotic genes (caspase-3 and Bax) were expressed only in SNP treatment groups. When bovine IVF embryos were co-cultured with BOEC supplemented with silymarin in the presence or absence of SNP, the development ability to blastocyst in 200 ???μM of silymarin alone was the highest among all treatments. These results suggest that silymarin has positive effects on cell characteristics such as viability, morphology and LPO of BOEC, and the increase of bovine IVF embryo development rate might be through antioxidative and anti-apoptotic actions.