Artesunate alleviates kidney fibrosis by restoring klotho protein and suppressing Wnt/β-catenin signalling pathway

Chronic kidney disease (CKD) is a global health concern that often progresses to renal failure and premature death. Regardless of etiology of CKD, kidney fibrosis is the main determinant of progressive CKD. Renal fibrosis is characterized by excessive collagen and extracellular-matrix (ECM) deposition, which impairs renal function with an irreversible loss of nephrons. Currently, there are no effective antifibrotic therapies to halt the progression of CKD to the end-stage-kidney-failure (ESKF). Artesunate has recently shown antifibrotic effects in various animal models, but its efficacy in renal fibrosis remains unexplored. In this study, the efficacy of artesunate was evaluated in a unilateral-ureteral-obstruction (UUO) mouse model and in primary human kidney fibroblasts (HKF). Mechanistic investigation including immunoblot analysis, immunohistochemistry, gene expression assay, enzyme-linked-immunosorbent assay (ELISA) and other tools were used to study the underlying molecular mechanisms of antifibrotic effects of artesunate. Results of this study showed that artesunate ameliorated multiple profibrotic pathways including transforming-growth-factor-beta (TGF-β) expression in UUO model and reduced profibrotic markers including alpha-smooth-muscle-actin (α-SMA), fibronectin, collagen I, and vimentin in both in-vivo and in-vitro models. Mechanistic studies indicated that artesunate treatment abrogated the TGF-β/SMAD pathway, restored klotho-protein expression and attenuated both PI3K/Akt and Wnt/β-catenin pathways. Additionally, artesunate inhibited cell-proliferation in UUO and induced ferroptosis in HKF cell culture. In conclusion, our study demonstrates that artesunate treatment abrogated fibroblast activation, attenuated canonical and non-canonical TGF-β pathways, inhibited cell proliferation in the UUO and selectively induced ferroptosis in HKF cell culture. These findings suggest that artesunate may have the potential to delay the progression of CKD and mitigate the development of kidney fibrosis, providing a promising direction for future therapeutic investigation.