Wang H, Liu H, Cheng H, Xue X, Ge Y, Wang X, Yuan J. Klotho Stabilizes the Podocyte Actin Cytoskeleton in Idiopathic Membranous Nephropathy through Regulating the TRPC6/CatL Pathway.
Am J Nephrol 2024;
55:345-360. [PMID:
38330925 DOI:
10.1159/000537732]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 02/05/2024] [Indexed: 02/10/2024]
Abstract
INTRODUCTION
The aim of this study was to explore the renoprotective effects of Klotho on podocyte injury mediated by complement activation and autoantibodies in idiopathic membranous nephropathy (IMN).
METHODS
Rat passive Heymann nephritis (PHN) was induced as an IMN model. Urine protein levels, serum biochemistry, kidney histology, and podocyte marker levels were assessed. In vitro, sublytic podocyte injury was induced by C5b-9. The expression of Klotho, transient receptor potential channel 6 (TRPC6), and cathepsin L (CatL); its substrate synaptopodin; and the intracellular Ca2+ concentration were detected via immunofluorescence. RhoA/ROCK pathway activity was measured by an activity quantitative detection kit, and the protein expression of phosphorylated-LIMK1 (p-LIMK1) and p-cofilin in podocytes was detected via Western blotting. Klotho knockdown and overexpression were performed to evaluate its role in regulating the TRPC6/CatL pathway.
RESULTS
PHN rats exhibited proteinuria, podocyte foot process effacement, decreased Klotho and Synaptopodin levels, and increased TRPC6 and CatL expression. The RhoA/ROCK pathway was activated by the increased phosphorylation of LIMK1 and cofilin. Similar changes were observed in C5b-9-injured podocytes. Klotho knockdown exacerbated podocyte injury, while Klotho overexpression partially ameliorated podocyte injury.
CONCLUSION
Klotho may protect against podocyte injury in IMN patients by inhibiting the TRPC6/CatL pathway. Klotho is a potential target for reducing proteinuria in IMN patients.
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