Targeting WNT5A noncanonical signaling attenuates renal fibrosis progression in acute kidney injury.

Preventing the progression from acute kidney injury (AKI) to chronic kidney disease (CKD) remains a considerable clinical challenge. In this study, we elucidate the role of WNT5A in accelerating the AKI-to-CKD transition and its underlying mechanisms. Renal biopsies from patients with AKI showed marked upregulation of WNT5A and its receptor, CD146, in proximal tubules, with higher expression in patients with CKD progression. In murine AKI models, Wnt5a knockdown attenuated CKD progression. Conversely, proximal tubular overexpression of Wnt5a exacerbated renal fibrosis in ischemia-reperfusion injury (IRI) mice, which was alleviated by Box5, a specific WNT5A antagonist. In vitro, WNT5A overexpression in transforming growth factor β (TGF-β)-stimulated HK-2 cells promoted CD146 upregulation, activated JNK phosphorylation, and enhanced SNAI1 expression. The genetic silencing of WNT5A/CD146 and JNK inhibition suppresses SNAI1 expression and attenuates fibrotic responses. Mechanistically, JNK-mediated c-JUN phosphorylation promoted its interaction with KLF5 at the SNAI1 promoter, driving renal fibrosis. Elevated serum levels of soluble CD146 correlated with renal function in patients with AKI and were higher in patients exhibiting CKD progression. Inhibition of WNT5A could serve as a therapeutic target for delaying renal fibrosis in AKI progression.