TY - JOUR AB - Bone morphogenetic protein 9 (BMP9) has recently been described as a crucial regulator in modulating fibroblast-type cell activation. Activin receptor-like kinase 1 (ALK1) is a high affinity receptor for BMP9 that exerts its role via Smad1/5. However, the functional roles of BMP9 in activating lung fibroblasts and the underlying signaling pathway are not completely understood. The present study aimed to explore the effect of exogenous BMP9 on human lung fibroblast HFL-1 cell proliferation and differentiation, as well as the potential role of the ALK1/Smad1/5 signaling pathway. In the present study, fibroblast proliferation was assessed using Cell Counting Kit-8 and colony formation assays, and the mRNA and protein expression of target genes was examined using reverse transcription-quantitative PCR and western blot assays, respectively. Compared with the control group, BMP9 treatment increased HFL-1 cell proliferation, mRNA and protein expression of differentiated markers, including α-smooth muscle actin, type I collagen and type III collagen, and the expression of ALK1 and phosphorylated Smad1/5 expression. Furthermore, the effects of BMP9 were partially rescued by dorsomorphin-1, an inhibitor of ALK1. The results indicated that BMP9 may serve as a key inducer of lung fibroblast activation and ALK1/Smad1/5 signaling might be associated with BMP9-mediated effects in HFL-1 cells. Therefore, the present study highlighted that the potential role of the BMP9/ALK1/Smad1/5 signaling pathway in the development of pulmonary fibrosis requires further investigation. AD - Department of Pathophysiology, Basic Medical College, Nanchang University, Nanchang, Jiangxi 330006, P.R. China Nanchang Joint Program, Queen Mary School, Nanchang University, Nanchang, Jiangxi 330031, P.R. China AU - Wang,Yaqun AU - Sima,Xiaonan AU - Ying,Ying AU - Huang,Yonghong DA - 2021/07/01 DO - 10.3892/etm.2021.10160 IS - 1 JO - Exp Ther Med KW - bone morphogenic protein 9 activin receptor-like kinase 1 proliferation differentiation lung fibroblast signaling pathway in vitro PY - 2021 SN - 1792-0981 1792-1015 SP - 728 ST - Exogenous BMP9 promotes lung fibroblast HFL-1 cell activation via ALK1/Smad1/5 signaling in vitro T2 - Experimental and Therapeutic Medicine TI - Exogenous BMP9 promotes lung fibroblast HFL-1 cell activation via ALK1/Smad1/5 signaling in vitro UR - https://doi.org/10.3892/etm.2021.10160 VL - 22 ER -