LINC00240/miR-155 Axis Regulates Function of Trophoblasts and M2 Macrophage Polarization via Modulating Oxidative Stress-Induced Pyroptosis in Preeclampsia

Abstract

Aim: This study aimed to investigate the effects of LINC00240/miR-155/Nrf2 axis on trophoblast function and macrophage polarization in the pathogenesis of preeclampsia. Methods: Bindings between LINC00240, miR-155 and Nrf2 were validated by dual luciferase reporter assay or RNA-immunoprecipitation method. Cell proliferation, migration, invasion, and pyroptosis were detected by CCK-8, clone formation, wound healing, Transwell system and flow cytometry, respectively. Macrophage polarization was tested by flow cytometry. LINC00240, miR-155 and Nrf2 levels, and oxidative stress and pyroptosis related-protein levels in in vitro and in vivo preeclampsia model were analyzed by qPCR, western blot or ELISA assays. Blood pressure, urine protein level, liver and kidney damages, and trophoblast marker in placenta tissues were further studied in vivo. Results: Placenta tissues from preeclampsia patients and animals showed decreased LINC00240 and Nrf2 expressions and increased miR-155 expression. LINC00240 directly bound and inhibited expression of miR-155, which then inhibited oxidative stress-induced pyroptosis, promoting proliferation, migration and invasion abilities of trophoblasts, and M2 macrophage polarization. Inhibition of miR-155 led to the increased Nrf2 expression and similar changes as LINC00240 in trophoblast function and macrophages polarization. Overexpression of LINC00240 in an in vivo preeclampsia model decreased blood pressure, urine protein, liver and kidney damages, increased fetal weight and length, and also induced trophoblast function and M2 macrophage polarization. Conclusion: LINC00240 inhibited symptoms of preeclampsia through regulation on miR-155/Nrf2 axis, which suppressed oxidative stress-induced pyroptosis to improve trophoblast functions and polarization of M2 macrophages. LINC00240 could be a potential therapeutic target for preeclampsia. Funding Statement: This work was supported by A study on serum proteomics and clinical application of pregnancy induced hypertension based on iTRAQ technology（ SB201901087） and Relationship between fibronectin and hypertensive disorder complicating pregnancy and its clinical application (192102310335). Declaration of Interests: The authors declare no conflict of interest. Ethics Approval Statement: Written informed consent was collected from all participants before the procedure. The research protocol was approved by the Ethical Committee of the Henan Provincial People’s Hospital (Zhengzhou, Henan, China). All the animal experiment procedures were approved by the Animal Ethics Committee of Henan Provincial People’s Hospital (Zhengzhou, Henan, China).