Role of ERK1/2 and PI3K/PKB signaling pathway in expression of extracellular matrix gene in pulmonary arterial smooth muscle cells in rat / 临床儿科杂志

ABSTRACT

Objective To explore the effects of the extracellular regulated protein kinase’s (ERK1/2) inhibitor PD98059 and ino-sitol triphosphate kinase (PI3K/PKB) signaling pathway’s inhibitor LY294002 on extracellular matrix (ECM) deposition in pulmonary arterial smooth muscle cells (PASMCs) stimulated by connective tissue growth factor (CTGF). Methods PASMCs of SD rat were cul-tured in vitro. The PASMCs were divided into control group, CTGF group, CP (CTGF+PD98059) group, CL (CTGF+LY294002) group and CPL (CTGF+PD98059+LY294002) group. Real-time lfuorescent quantitative RT-PCR was used to detect the expression of colla-gen III and ifbronectin mRNA of PASMCs, and the expression of collagenШprotein of PASMCs was detected by immunohistochem-istry and western-blot. Results The expressions of collagenШand ifbronectin mRNA of PASMCs stimulated with CTGF (50 ng/ml) for 48 h were signiifcantly higher than those in control group, and the collagen proteinШof PASMCs was decreased signiifcantly after stimulation with CTGF (50 ng/ml) for 72 h (P<0.05). The expressions of collagenШand ifbronectin mRNA in PASMCs cultured with PD98059 (20μmol/L) and/or LY294002 (10μmol/L) for 48 h was signiifcantly lower than those in CTGF group (P<0.05). The collagen proteinШin PASMCs cultured with PD98059 (20μmol/L) and/or LY294002 (10μmol/L) for 72 h was increased (P<0.05). The expres-sions of collagenШand ifbronectin mRNA of PASMCs stimulated with both PD98059 and LY294002 were more signiifcant. Conclu-sions CTGF may increase the expression of collagenШand ifbronectin mRNA in PASMCs, which may contribute to the deposition of ECM in PASMCs during pulmonary vascular remodeling. PD98059 and LY294002 may repress ERK1/2 and PI3K/PKB signaling pathways and interfere with the biological effect of CTGF.