KLF9 mediates NLRP3 inflammasome and reactive oxygen species to mediate pyroptosis in trophoblasts

Introduction The objective of this study was to explore the effect of KLF9 on oxidative stress (OS) and NLRP3-mediated inflammation in preeclampsia (PE). Methods Lipopolysaccharide (LPS)+adenosine triphosphate (ATP)-induced HTR-8/SVneo cells were used as an in vitro PE inflammation cell model. shRNA was used to interfere with KLF9 expression (sh-KLF9) to assess the transfection efficiency and the effect of KLF9 on cell proliferation, migration, and invasion. ELISA was performed to detect OS-related factors and inflammatory cytokines. Reactive oxygen species (ROS) levels and pyroptosis were analyzed using DCFH-DA and TUNEL staining. LPS and ATP induced HTR-8/SVneo cells were co-transfected with sh-PRDX6/sh-KLF9 to explore the potential regulatory effect of KLF9 on PRDX6. Results LPS+ATP stimulation increased KLF9 expression in the PE cell model. Specifically, reducing KLF9 levels alleviated morphological damage and enhanced proliferation, migration, and invasion in the in vitro PE cell models. Moreover, inhibiting KLF9 expression decreased protein expression of NLRP3, GSDMD-N, cleaved caspase-1, and cleaved-IL-1β, suppressing cell death in LPS+ATP-induced HTR-8/SVneo cells. Analysis of OS indicators revealed that downregulating KLF9 expression restrained intracellular ROS production, decreased MDA expression, and increased SOD and CAT levels. KLF9 regulated the transcription of PRDX6 to attenuate OS and pyroptosis. Knockdown of PRDX6 partially abolished the effect of KLF9 downregulation on OS and pyroptosis of LPS+ATP-induced HTR-8/SVneo cells, as evidenced by the inhibition of cell proliferation, migration, and invasion, as well as the enhanced activity of the NLRP3 inflammasome. Conclusion Downregulation of KLF9 enhances trophoblast cell invasion and reduces OS and NLRP3 inflammasome activation-mediated pyroptosis.