IL-33对大鼠I/R损伤心肌炎症反应和细胞自噬的影响

Effect of interleukin 33 on inflammation response and autophagy in rats with myocardial ischemia-reperfusion injury

目的探讨IL-33对心肌缺血再灌注(I/R)损伤心肌的保护作用及机制。方法将32只大鼠随机分为假手术组(n=10)、模型组(n=10)、IL-33组(n=6)及IL-33特异性受体(ST2)抑制剂组(anti-ST2组,n=6)。除假手术组外,其余各组采用结扎冠状动脉左前降支法建立I/R心肌损伤模型。假手术组仅麻醉、开胸、穿线,但不结扎。IL-33制模前30 min尾静脉注射IL-33 10μg,anti-ST2组注射anti-ST2 0.2 m L(1mg/m L)。再灌注4 h后取血清或心肌组织检测各组以下指标:1血清乳酸脱氢酶(LDH)、肌酸激酶(CK)水平:采用分光光度法检测;2心肌组织Th1型炎症因子(TNF-α、INF-γ、IL-6)和Th2型炎症因子(IL-4、IL-5、IL-13)水平:采用ELISA法检测;3心肌组织自噬蛋白LC3和beclin-1相对表达量:采用Western blot法检测。结果 1LDH、CK水平:模型组均明显高于假手术组,IL-33组均明显低于模型组,P均<0.05;anti-ST2组较模型组无统计学差异。2心肌组织炎症因子表达:Th1型炎症因子模型组及IL-33组均明显高于假手术组,IL-33组明显低于模型组,P均<0.05;anti-ST2组与模型组比较无统计学差异。Th2型炎症因子模型组明显低于假手术组,IL-33组明显高于模型组,anti-ST2组与模型组比较无统计学差异;3心肌组织自噬蛋白LC3和beclin-1相对表达量:模型组明显高于、IL-33组明显低于假手术组;IL-33组明显低于模型组(P均<0.05);anti-ST2组与模型组比较无统计学差异。IL-33与anti-ST2组各观察指标均有统计学差异(P均<0.05)。结论 IL-33可通过抑制细胞过度自噬,减弱Th1型炎症反应,促进Th2型炎症反应而减轻心肌I/R损伤。

Objective To investigate the protective effect of interleukin 33（ IL-33） on myocardial ischemia-reperfusion（ I / R） injury and the mechanism. Methods Thirty-two rats were randomly divided into 4 groups： the control group（ n = 10）,I/R group（ model group,n = 10）,IL-33 group（ n = 6） and anti-ST2 group（ n = 6）. In addition to the control group,the left anterior descending coronary artery ligation method was adopted to establish the myocardial I / R injury model in the other groups（ the sham operation group only received anesthesia,open-chest and threading,but not ligation）. Rats in the IL-33 ＋ I / R group and anti-ST2 ＋ I / R group were separately injected to the caudal vein with 10 μg IL-33 and 0. 2 m L anti-ST2（ 1 mg / m L） 30 min before modeling. After reperfusion for 4 h,we obtained the serum or myocardial tissues to detect the following indicators of each group：（ 1） the serum lactate dehydrogenase（ LDH） and creatine kinase（ CK） level：using spectrophotometry,（ 2） Th1 inflammation factors in the myocardial tissues（ TNF-α,INF-γ and IL-6） and Th2 inflammatory cytokines（ IL-4,IL-5 and IL-3） ： using the ELISA,（ 3） the relative expression of autophagy protein LC3 and beclin 1 in the myocardial tissues： using Western blotting. Results（ 1） LDH and CK level： the model group was significantly higher than the control group,IL-33 group was significantly lower than the model group（ P〈0. 05）,and no statistical difference was found between the anti-ST2 group and the model group.（ 2） the inflammation factor expression in the myocardial tissues： Th1 type inflammation factor expression： the model group and IL-33 group were significantly higher than the control group,IL-33 was significantly lower than the model group（ all P〈0. 05）,and no difference was found between the anti-ST2 group and the model group. Th2 type inflammation factor expression： the model group was significantly lower than the control group,IL-33 group was significantly higher than the model group,and no statistical difference was found between the anti-ST2 group and the model group.（ 3） The relative expression of autophagy protein LC3 and beclin-1 in the myocardial tissues： the model group was significantly higher,IL-33 group was significantly lower than the control group,IL-33 was significantly lower than the model group（ all P〈0. 05）,no significant difference was found between the anti-ST2 group and the model group. Statistically significant differences were found in all indexes between the IL-33 and anti-ST2 group. Conclusion IL-33 may attenuate myocardial I / R injury by inhibiting the excessive autophagy,weakening Th1 inflammatory response and enhancing Th2 inflammatory response.