Rynchopeterine inhibits the formation of hypertrophic scars by regulating the miR-21/HIF1AN axis

Hypertrophic scar (HS) is a fibroproliferative skin disease characterized by abnormal wound healing and pathological excessive fibrosis of the skin. Currently, the molecular mechanism of the disease is still largely unknown, and there is no effective drug treatment. In this study, we explored the effect of Rynchopeterine on the formation of HS. HS fibroblasts (HSFs) were isolated from the HS tissues of patients recovering from severe burns. After treating HSFs with different concentrations of Rynchopeterine, CCK-8, EdU, and Annexin V-FITC/PI assays were used to detect the proliferation, apoptosis, and contractile ability of HSFs, respectively. RT-qPCR and Western blotting were performed to evaluate the effect of Rynchopeterine on the expression of miR-21 and hypoxia-inducible factor 1-alpha subunit suppressor (HIF1AN), respectively. The dual-luciferase reporter gene was used to verify the targeting relationship between miR-21 and HIF1AN. Rynchopeterine reduced the expression of Col1a2, Col3a1 and α-SMA, proliferation and contraction of HSFs, and increased apoptosis in a dose-dependent manner. miR-21 was highly expressed in HS tissues and HSFs, and Rynchopeterine could inhibit miR-21 expression. Overexpression of miR-21 and knockdown of HIF1AN increased proliferation, activation, contraction, and collagen synthesis of HSFs, and inhibited their apoptosis. In vivo, Rynchopeterine could reduce the collagen content of the dermis and the positive ratio of PCNA and α-SMA. Rynchopeterine is a good therapeutic agent for HS, which up-regulates the expression of HIF1AN by inhibiting miR-21, thereby inhibiting the formation of HS.