白介素33下调高迁移率族蛋白1保护大鼠缺血再灌注心肌的研究

Interleukin 33 in Protecting Myocardial Ischemia and Reperfusion Injury by Down Regulation of HMGB1 Expression in Rats

目的探讨白介素33(IL-33)是否可以通过调控高迁移率族蛋白1(HMGB1)表达保护大鼠缺血再灌注(I/R)心肌。方法将32只成年雄性SD大鼠随机分为4组:假手术(SO)组(n=10)、I/R模型组(n=10)、IL-33组(n=6)、HMGB1抗体(HMGB1 Ab)组(n=6)。SO组大鼠开胸,左前降支(LAD)下穿线,但不结扎;其余3组制作大鼠I/R模型,IL-33组于造模前30 min予尾静脉注射IL-33 10μg,HMGB1 Ab组于造模前30 min予尾静脉注射IL-3310μg及HMGB1中和抗体。检测各组血清乳酸脱氢酶(LDH)、肌酸激酶(CK)水平,心肌组织肿瘤坏死因子-α(TNF-α)、白介素6(IL-6)、HMGB1、总半胱氨酸天冬氨酸蛋白酶-3(Caspase-3)、活化Caspase-3、Bcl-2、Bax表达,定量检测SO组、I/R组、IL-33组心肌组织中HMGB1 mRNA。结果再灌注4 h后,IL-33可明显降低I/R大鼠血清LDH、CK水平,降低心肌组织TNF-α、IL-6、HMGB1、Bax的表达和Caspase-3活化(P<0.05),升高Bcl-2表达(P<0.05);HMGB1可减弱IL-33的上述作用(P<0.05)。结论 IL-33可通过抑制心肌组织中HMGB1表达进而抑制心肌炎症反应和细胞凋亡,保护I/R心肌。

Objective To investigate the protective effect of interleukin-33 （IL-33） on myocardial ischemia and reperfusion injury （I/R） by down regulation of high mobility group proteinl （HMGB1） expression in rats. Methods The 32 adult male SD rats were randomly divided into sham operation group （ SO group, n = 10）, I/R group （ n = 10）, IL-33 group （n =6） and HMGB1 antibodies group （HMGB1 Ab group, n =6）. The rats in SO group underwent chest cutting operation, and a suture was passed through the myocardium beneath the left anterior descending （LAD） without ligation; while the I/R models were established in rats in the rats in other 3 groups, and the rats in IL-33 and HMGB1 Ab groups were treated with IL-33 10μg and IL-33 10μg ＋ HMGB1 neutralizing antibody respectively by vena caudalis injection 30 min before the model establishment. The levels of serum lactate dehydrogenase （LDH） and creatine kinase （CK）, and expressions of tumor necrosis factor-α （TNF-α） , IL-6, HMGB1, total Caspase-3, cleaved Caspase-3, Bcl- 2 and Bax in all groups were detected, and HMGB1 mRNA levels in SO, I/R and IL-33 groups were quantificationally detected. Results After reperfusion for 4 h, IL-33 could significantly decrease LDH and CK levels and the TNF-α, IL- 6, HMGB1 and Bax expressions, and Caspase-3 activation （P 〈 0. 05）, but increase the Bcl-2 expression （P 〈 0. 05） ; while HMGB1 could weaken protective effect of IL-33 （P 〈 0. 05 ）. Conclusion IL-33 may inhibit myocardial inflammatory reaction and apoptosis by inhibiting HMGB1 expression in myocardial tissues so as to protect I/R myocardium.