Effects of Bai zhu san (Atractylodis macrocephalae) decoction on cellular immunity and Th1/Th2 cytokine ratio in a Mifepristone-induced murine abortion model

Chinese herbal medicine has been used as an anti-abortive treatment in farm animals for thousands of years. To investigate the anti-abortive functions and mechanisms of Bai zhu san (BZS) on mifepristone (RU-486)-induced abortion, pregnant mice were allocated to different groups as follows: control group receiving neither RU-486 nor BZS; mice receiving RU-486 only; mice treated with both RU-486 and BZS. The results showed that the concentrations of IL-10 and IL-4 in uterine lysates were significantly higher in mice of the BZS + RU-486 group compared with the mice of the RU-486 group. The IL-10 and IL-4 levels in serum were several folds higher than that in uterus lysates. The IFN-γ concentrations in uterine lysate decreased significantly in mice of the BZS + RU-486 group vs. the RU-486 group. There were no significant differences in IL-2 concentrations between the mice of BZS + RU-486 or RU-486 groups and controls in the uterus and serum. The numbers of CD4+, CD8+T lymphocytes or macrophages in the uterus decreased in the BZS + RU-486 group compared with the RU-486 group. These results indicate that the Chinese herbal formula Bai zhu san inhibits RU-486-induced abortion and modulates the Th1/Th2 cytokine balance at the maternal-foetal interface.