Objective To investigate the effects of simvastatin on the collagen synthesis of rat pulmonary arterial smooth muscle cells ( PASMCs ) induced by hypoxia. Methods Under hypoxic condition, rat PASMCs were cultured with different concentrations of simvastatin. Collagen synthesis of PASMCs with or without simvastatin were measured by 3H-proline incorporation assay. The mRNA expression of TGF-β1 and the contents of super oxide dismrtase ( SOD) ,malondialdehyde ( MDA) in mediumwere also measured. Results The incorporation data of 3H-TdR in the hypoxia group was significantly increased as compared with that in the control group ( P lt;0. 01) , and simvastatin significantly reduced the incorporation data of 3H-TdR induced by hypoxia. The expression of TGF-β1 mRNA in the hypoxia group was significantly increased as compared with that in the control group ( P lt; 0. 01 ) , and simvastatin could significantly inhibited hypoxia-induced expression of TGF-β1 mRNA in a dose-dependent manner. Compared with the hypoxia group, the expression of TGF-β1 mRNA decreased by 55% in simvastatin( 10 - 6mol /L) group ( P lt; 0. 01) , and by 70% ( P lt; 0. 01) in simvastatin ( 10 - 5mol /L) group. Compared with the control group, the activity of SOD was reduced and the contents of MDA were increased significantly in the hypoxia group. Simvastatin can increase the activity of SOD and reduced the content of MDA in a dose-dependent manner. Conclusions Simvastatin can decreases collagen synthesis of PASMCs. This effect might be explained that simvastatin can reduce lipid peroxide and expression of TGF-β1 mRNA.
ObjectiveTo investigate the effects of 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole (YC-1), a hypoxia-inducible factor-1α (HIF-1α) inhibitor, on hypoxia induced rat pulmonary arterial adventitial fibroblasts (AFs) proliferation and collagen synthesis, and explore the molecular mechanism.MethodsUnder hypoxic condition, rat AFs were cultured in DMEM medium supplemented with 10% fetal bovine serum in vitro. The cells were divided into five groups, ie. a normoxia group, a hypoxia group and three hypoxia+YC-1 groups (treated with YC-1 at concentration of 0.01, 0.05 and 0.1 mmol/L, respectively). The cells proliferation was determined by MTT method. Collagen synthesis of AFs was measured by 3H-proline incorporation assay. The expression of HIF-1α in AFs in different conditions was measured by Western blot, and the mRNA expression of transforming growth factor-β1 (TGF-β1) was measured by reverse-transcription polymerase chain reaction.ResultsThe proliferation rate and the incorporation data of 3H-proline in the hypoxia group were significantly increased as compared with those in the control group (both P<0.01). YC-1 significantly reduced the proliferation rate and incorporation data of3H-proline induced by hypoxia in a dose-dependent manner. YC-1 could also down-regulate the expressions of HIF-1α and TGF-β1 mRNA significantly (both P<0.01). Compared with the hypoxia group, the expressions of HIF-1α and TGF-β1 mRNA decreased respectively by 65% and 61% in the hypoxia+YC-1 (0.1 mmol/L) group (bothP<0.01).ConclusionsYC-1 can inhibit hypoxia-induced AFs proliferation and collagen synthesis in a dose-dependent manner. The mechanism may relate to YC-1’s inhibitory effect on expressions of HIF-1α and TGF-β1 mRNA.