摘要
Abstract
Objective To investigate the regulation of plasminogen activator inhibitor-1 (PAI-1) on the proliferation of airway smooth muscle cells (ASMCs) and its effect on extracellular regulated protein kinase (ERK).Methods The ASMCs of mice cultured in vitro were divided into 7 groups:control group,PAI-1 5 μg/L group,PAI-1 10 μg/L group,PAI-1 20 μg/L group,PAI-1 40 μg/L group,PAI-1 80 μg/L group and PAI-1 100 μg/L group.All groups were cultured respectively for 12,24 and 48 h in a 37℃ incubator.The absorbance values were tested by CCK-8,and the proliferation rates were calculated.The concentration and intervention time of the experimental group with the highest proliferation rate were taken as the optimal concentration and time of PAI-1 action.Then the subjects were further divided into 6 groups:group A (blank control),group B (PAI-1 20 μg/L),group C (PAI-1 40 μg/L),group D (PAI-i 80 μg/L),group E (PAI-1100 μg/L) and group F (the optimal concentration of PAI-l+the inhibitor of ERK PD98059 10 μ mol/L).The proliferation of ASMCs was detected by CCK-8.The expression of ERK protein was detected by Western blot.And the expression of ERK mRNA was detected by qRT-PCR.Results After 5-100 μg/L PAI-1 acted upon ASMCs for 12,24 and 4-8 h,the proliferation rates of each test group at different time points were statistically different (P＜ 0.05),and the proliferation rates reached the maximal levels at the 4-8th h;at the same time point the proliferation rates of the test groups with different concentrations were statistically different (P＜ 0.05),and the proliferation rates of ASMCs reached the peak at the concentration of 80 μg/L.Therefore,80 μg/L of PAI-1 was chosen to be the optimum concentration,and 4-8 hours was set to be the optimal intervention period for the subsequent experiments.In the subsequent experiments,the results showed that compared to the group A,ERK phosphorylation levels and the expressions of ERK mRNA in the groups B,C,D and E were significantly increased (P ＜ 0.05);in the pairwise comparison of the groups B,C,D and E,the ERK phosphorylation levels and the expressions of ERK mRNA in the ASMCs were statistically different only between the groups B and E (P ＜ 0.05).When PAI-1 concentration varied from 20 to 80 μg/L,ERK phosphorylation level and the expression of ERK mRNA increased with the concentration;when the concentration went up over 80 μg/L,the phosphorylation level of ERK no longer increased.Compared with the group D,the ERK phosphorylation level and the expression of ERK mRNA were decreased in the group F (added with PD98059) (P ＜ 0.05).Conclusions Exogenous PAI-1 may promote the proliferation of ASMCs through ERK pathway.关键词
纤溶酶原激活物抑制物-1/细胞外调节蛋白激酶/气道平滑肌细胞/哮喘Key words
plasminogen activator inhibitor-1/extracellular regulated protein kinase/airway smooth muscle cells/asthma分类
医药卫生
