脂多糖对大鼠肝星状细胞caspase-1及IL-18表达的影响

Effects of lipopolysaccharide on caspase-1 and IL-18 expression in rat hepatic stellate cells

目的观察脂多糖(LPS)诱导大鼠肝星状细胞NLRP3活化时caspase-1及IL-18表达的变化。方法常规培养大鼠肝星状细胞,用RT-PCR检测LPS诱导肝星状细胞2 h时NLRP3炎症小体及caspase-1,IL-18 mRNA的表达,荧光定量PCR检测不同浓度LPS(0,0.05,0.1,0.2μg/ml)诱导肝星状细胞不同时间(30,60,120 min)时caspase-1及IL-18 mRNA的表达。结果 LPS诱导肝星状细胞在30 min和60 min时,随着LPS浓度增加caspase-1和IL-18 mRNA表达增高,0.1和0.2μg/ml组均显著高于0μg/ml组(P<0.05);120 min时,随着LPS浓度增加caspase-1和IL-18 mRNA表达逐渐降低,其中0.05μg/ml组较0μg/ml组显著降低(P<0.05)。随LPS诱导时间延长,0.05μg/ml组caspase-1和IL-18 mRNA表达逐渐增加;在0.1μg/ml和0.2μg/ml组,caspase-1 mRNA表达逐渐降低,其中120 min组较30 min组显著降低(P<0.05);IL-18 mRNA表达水平先升高后降低,均在60 min时达最高水平(P<0.01)。结论 LPS能够促进肝星状细胞炎症小体NLRP3表达,激活NLRP3,诱导HSC-T6分泌caspase-1及IL-18。

Objective To investigate the expression of caspase-1 and IL-18 in hepatic stellate cells when NLRP3 activation is induced by lipopolysaccharide（ LPS）. Methods Rat hepatic stellate cells were conventionally cultured. The expression levels of NLRP3,caspase-1 and IL-18 mRNA in hepatic stellate cells induced by LPS for 2 h were detected by RT-PCR,and the caspase-1 and IL-18 mRNA expression levels were detected by quantitative PCR at different time points（ 30,60,120 min） when stellate cells were induced by different doses of LPS（ 0,0. 05,0. 1,0. 2 μg / ml）. Results At 30 min and 60 min,the caspase-1 and IL-18 mRNA expression levels increased in a concentration-dependent manner,and they were significantly higher in 0. 1 μg / ml and 0. 2 μg / ml group than in 0μg /ml group（ P〈0. 05）. At 120 min,the expression of caspase-1 and IL-18 mRNA was decreased in a concentration-dependent manner,and it was significantly lower in 0. 05 μg / ml group than in 0 μg / ml group（ P〈0. 05）. With the enlargement of treatment,the caspase-1 and IL-18 mRNA expression was increased in 0. 05 μg / ml group,while the caspase-1 mRNA expression decreased in 0. 1μg /ml and 0. 2 μg /ml group,it was significantly lower at 120 min than at 30 min（ P〈0. 05）. The IL-18 mRNA expression was increased first and then reduced,and peaked at 60 min（ P 〈0. 01）. Conclusion LPS can promote the inflammasome NLRP3 expression in hepatic stellate cells,activate the NLRP3,and thus induce the HSC-T6 secreting caspase-1 and IL-18.