ANXA6 Overexpression Causes Abnormal Decidual Macrophage-Trophoblast Crosstalk in Recurrent Spontaneous Abortion.

ANXA6 is involved in numerous biological processes; however, its association with recurrent spontaneous abortion (RSA) remains poorly understood. In this study, we observed significant upregulation of ANXA6 expression in decidual macrophages from RSA patients. Functional analysis revealed that ANXA6 overexpression enhanced reactive oxygen species (ROS) generation and reduced mitochondrial membrane potential, thereby promoting pyroptosis and upregulating M1 macrophage polarization markers. Mechanistically, inhibition of NLRP3 rescued ANXA6 overexpression-induced elevation of M1 polarization and pyroptosis in macrophages. In addition, inhibition of ROS alleviated the decreased mitochondrial membrane potential, aggravated macrophage pyroptosis, and exacerbated inflammatory response, as well as the promoted macrophage M1 polarization caused by ANXA6 overexpression. Further mechanisms suggest that overexpression of ANXA6 in macrophages could promote the accumulation of mitochondrial ROS and inhibit mitochondrial membrane potential through the NF-κB signaling pathway, exacerbating macrophage pyroptosis and amplifying the resulting inflammatory response, thereby promoting macrophage M1 polarization. Besides, ANXA6 overexpressing macrophages showed an inhibitory effect on trophoblast function in vitro, a process mediated through TNF-α inhibition of the PI3K/AKT axis. Collectively, our study reveals that ANXA6 is a key mediator of immune dysregulation at the maternal-fetal interface in RSA patients.