Dihydroartemisinin attenuates renal fibrosis through regulation of fibroblast proliferation and differentiation

Abstract

Aims: Renal fibrosis is the most common final stage of progressive renal disease, characterized by fibroblast proliferation, fibroblast-to-myofibroblast differentiation and excessive accumulation of extracellular matrix. Dihydroartemisinin (DHA) exerts antitumor, antibacterial, and antifibrotic effects. The aim of this study was to determine whether DHA has beneficial effects on unilateral ureteral obstruction (UUO)-induced renal fibrosis in mice and to examine explore the underlying possible mechanisms.

Materials and methods: Eight-week-old male C57BL/6 mice were intragastrically administered DHA for 14 consecutive days after UUO operation. Afterward, interstitial collagen deposition, expression of collagen I and III, fibronectin, α-smooth muscle actin (α-SMA), proliferating cell nuclear antigen (PCNA), and S100 calcium-binding protein A4 (S100A4) were assessed in the kidneys. Transforming growth factor beta 1 (TGF-β1)-induced primary human kidney fibroblasts were treated with DHA to further investigate the mechanism underlying its action.

Key findings: In vivo, DHA reduced UUO-induced morphological and pathological changes and the degree of renal fibrosis. In addition, DHA mitigated fibroblast proliferation and differentiation in kidney tissue induced by UUO. In vitro, DHA significantly attenuated the TGF-β1-induced primary human kidney fibroblast proliferation and fibroblast-to-myofibroblast differentiation. Moreover, treatment with DHA attenuated the up-regulation of phosphorylation of phosphatidylinositol-3-kinase (PI3K) and protein kinase B (AKT) in UUO model and TGF-β1-induced primary human kidney fibroblasts.

Significance: We provide in vivo and in vitro evidence that DHA may relieve renal fibrosis through regulation of fibroblast proliferation and differentiation by mitigating the PI3K/AKT pathway. DHA may potentially be used as a therapeutic antifibrotic agent for the treatment of renal fibrosis.

Keywords: Differentiation; Dihydroartemisinin; Fibroblast; PI3K/AKT; Proliferation; Renal fibrosis; TGF-β1; Unilateral ureteral obstruction.