Mechanistic study on lncRNA XIST/miR-124-3p/ITGB1 axis in renal fibrosis in obstructive nephropathy

Objective: The purpose of this study was to investigate the role and possible mechanism of lncRNA XIST in renal fibrosis and to provide potential endogenous targets for renal fibrosis in obstructive nephropathy (ON). Methods: The study included 50 cases of ON with renal fibrosis (samples taken from patients undergoing nephrectomy due to ON) and 50 cases of normal renal tissue (samples taken from patients undergoing total or partial nephrectomy due to accidental injury, congenital malformations, and benign tumors). Treatment of human proximal renal tubular epithelium (HK-2) cells with TGF-(31 simulated renal fibrosis in vitro. Cell viability and proliferation were measured by CCK-8 and EdU, and cell migration was measured by transwell. XIST, miR124-3p, ITGB1, and epithelial-mesenchymal transition (EMT)-related proteins (E-cadherin, a-SMA, and fibronectin) were detected by PCR and immunoblot. The targeting relationship between miR-124-3p and XIST or ITGB1 was verified by starBase and dual luciferase reporter gene experiments. In addition, The left ureter was ligated in mice as a model of unilateral ureteral obstruction (UUO), and the renal histopathology was observed by HE staining and Masson staining. Results: ON patients with renal fibrosis had elevated XIST and ITGB1 levels and reduced miR-124-3p levels. The administration of TGF-(31 exhibited a dose-dependent promotion of HK-2 cell viability, proliferation, migration, and EMT. Conversely, depleting XIST or enhancing miR-124-3p hindered HK-2 cell viability, proliferation, migration, and EMT in TGF-(31-damaged HK-2 cells HK-2 cells. XIST functioned as a miR-124-3p sponge. Additionally, miR-124-3p negatively regulated ITGB1 expression. Elevating ITGB1 weakened the impact of XIST depletion on TGF-(31-damaged HK-2 cells. Down-regulating XIST improved renal fibrosis in UUO mice. Conclusion: XIST promotes renal fibrosis in ON by elevating miR-124-3p and reducing ITGB1 expressions.