Bushen Antai recipe attenuates recurrent spontaneous abortion by activating VEGFA/p-AKT/SESN2 to restore trophoblast endoplasmic reticulum homeostasis

ETHNOPHARMACOLOGICAL RELEVANCE: Recurrent spontaneous abortion (RSA) remains a formidable clinical challenge with limited therapeutic options, largely attributed to trophoblast dysfunction as a central pathological mechanism. Bushen Antai recipe (BAR) has demonstrated encouraging clinical and experimental efficacy in pregnancy support. However, its bioactive constituents and molecular mechanisms, especially in the context of trophoblasts, remain poorly understood. AIM OF THE STUDY: To evaluate the therapeutic efficacy of BAR in RSA and elucidate its underlying mechanisms, with a particular focus on trophoblast function, using an integrated strategy. MATERIALS AND METHODS: UPLC-Q-TOF-MS/MS was employed to profile chemical constituents of BAR and its serum-absorbed components. An RU486-induced abortion-prone mouse model and HTR-8/SVneo trophoblast injury model were established to evaluate the effects of BAR on embryonic development and placentation. Label-free quantitative proteomics, network pharmacology, molecular docking, viral transduction, together with transmission electron microscopy imaging, morphological analysis, Western blot, immunofluorescence, and various cellular functional assays were performed to decipher the underlying mechanisms. RESULTS: BAR significantly reduced embryo resorption, restored placental architecture, and improved trophoblast survival and function in abortion-prone mice. Proteomics revealed endoplasmic reticulum (ER) stress as a prominent pathological feature in placentas from the RU486-induced abortion-prone mouse model, a condition that was effectively ameliorated by BAR treatment. Network pharmacology predicted VEGFA as a core target, subsequently validated by experiments demonstrating that BAR activates the VEGFA/p-AKT/SESN2 axis to reprogram the dynamics of all three unfolded protein response (UPR) branches and re-establish ER homeostasis. Serum pharmacochemistry identified 72 absorbed constituents, with molecular docking revealing that multiple compounds including quercetin, calycosin, loganin, and sweroside were predicted to bind VEGFA. CONCLUSIONS: This integrative study provides evidence that BAR modulates UPR dynamics and contributes to the restoration of ER homeostasis via a VEGFA-associated p-AKT/SESN2 signaling axis, thereby supporting trophoblast function and preventing recurrent pregnancy loss, with multiple bioactive constituents potentially converging on VEGFA synergistically.