Jianwei Shoutai Pills alleviates miscarriage by modulating gut microbial production of BAs and NLRP3-inflammasome at the maternal-fetal interface of rats.

Background: Miscarriage has the characteristics of recurrent attacks and complex etiology, so it is gradually attracted the wide attention of scholars in the fields of reproduction. Potential association between gut microbiome (GM) and pregnancy disorders has been investigated. Jianwei Shoutai pills (JWP), as a representative formula, have been proven to have protective effect in both clinical and experimental research in miscarriage. However, the specific mechanism of JWP in miscarriage through GM remains unclear.

Purpose: To investigate the underlying mechanism of JWP against miscarriage through the gut-uterus axis.

Methods: The effects of JWP on an RU486-induced rat model of miscarriage were evaluated by embryo resorption rate, vaginal bleeding rate, and appearance of the uterus and embryo. We used 16S rRNA sequencing to measure the extent of the effect of JWP on GM of rats with miscarriage. Bile acid (BA) content of the feces of rats treated with JWP was evaluated by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS). The activation of bile acid-associated receptor, Farnesoid X receptor (FXR), was evaluated by immunofluorescence. The expression level of NLRP3 inflammasome-associated protein was detected by Western blot or Elisa. Fecal microbiota transplantation (FMT) was used to confirm that GM was essential for the therapeutic effect of JWP in miscarriage.

Results: JWP significantly ameliorated miscarriage symptoms and embryo resorption rate caused by RU486-induced miscarriage as well as restored the abnormal activation of NLRP3-inflammasome at the maternal-fetal interface. Furthermore, JWP can significantly regulated GM dysbiosis and closely associated with BA metabolism by KEGG pathway prediction analysis. Several BA content were significantly restored by HPLC-MS. The expression of NLRP3 inflammasome-associated protein at maternal-fetal interface was reversed by JWP. Combined with FMT, JWP could regulate activation of NLRP3 at the maternal-fetal interface by BAs produced by GM.

Conclusion: JWP restored abnormal activation of the NLRP3-inflammasome in an RU486-induced miscarriage rat model, and corrected the BA disorder by regulating imbalance of the GM.