硫化氢对脓毒症大鼠心肌损伤的作用及其机制探讨

Effect and Mechanism of Hydrogen Sulfide on Septic Rats with Myocardial Injury

目的研究硫化氢(hydrogen sulfide,H2S)对脓毒症大鼠心肌损伤的作用,并探讨其作用的可能机制。方法采用盲肠结扎穿孔法制备大鼠脓毒症(cecal ligation and puncture,CLP)模型,将SD大鼠随机分为6组:假手术组、假手术+外源性H2S供体硫氢化钠(NaHS)组、假手术+H2S合成酶胱硫醚-γ-裂解酶(cystathionine-γ-lyase,CSE)抑制剂炔丙基甘氨酸(propargylglycine,PAG)组、CLP组、CLP+NaHS组、CLP+PAG组,每组各24只大鼠。分别于术后6h、12h、24h处死各组大鼠(即各组分6h、12h、24h亚组)取血和心肌标本,检测血清肌钙蛋白I(cTnI)水平,大鼠心肌组织HE染色观察病理变化,测定心肌组织肿瘤坏死因子-α(TNF-α)、白细胞介素-10(IL-10)含量,采用RT-PCR方法检测心肌组织CSE mRNA表达,Western blot检测大鼠心肌组织核转录因子NF-κB表达。结果假手术各组及不同时点各指标差异均无统计学意义。与假手术12h及24h组相比,CLP 12h及24h组血清cTnI质量浓度以及心肌组织病理评分、心肌组织CSE mRNA、NF-κB表达、TNF-α及IL-10含量均升高(P均<0.05);与CLP 12h及24h组相比,CLP+NaHS 12h及24h组血清cTnI质量浓度以及心肌组织病理评分、NF-κB表达和TNF-α含量降低(P均<0.05),CSE mRNA表达和IL-10含量升高(P均<0.05);而CLP+PAG 12h及24h组血清cTnI质量浓度及心肌组织病理评分、NF-κB表达和TNF-α含量升高(P均<0.05),CSE mRNA表达和IL-10含量降低(P均<0.05)。结论 H2S在脓毒症所致的心肌损伤中起保护作用,这种保护作用的机制可能是通过抑制心肌组织中NF-κB表达、降低心肌组织TNF-α含量和提高心肌组织CSE mRNA表达、IL-10含量而保护心肌组织。

Objective To study the effects of hydrogen sulfide（H2 S）on myocardial injury in sepsis rats,and to explore the possible mechanism of H2 S on myocardial injury induced by sepsis.Methods Cecal ligation and puncture（CLP）method was used to establish sepsis rat model.SD rats were randomly divided into 6 groups：sham operation group,sham operation ＋ exogenous H2 S donor sodium thiohydride group,pseudosurgery ＋ H2 S synthase cthioether-ether lyase（cystathionine-γ-lyase,CSE）inhibitor propargylglycine（propargylglycine,PAG）group,CLP model group,CLP model＋NaHS group,CLP model＋PAG group,24 rats in each group.Blood and myocardial specimens were collected from the subgroups of COP for 6 h,12 hand 24 h,respectively.Serum myocardial calcitonin I（cTnI）level,TNF-α,IL-10 were detected,and the pathological changes were observed by HE staining of rat myocardial tissue.The expression of CSE mRNA in cardiomyocytes was detected by RT-PCR,Western blot assay was used to detect the expression of cardiac transcription factor NF-κB in rats.Results There was no statistically significant difference in each group and time point of sham operation groups.Compared to the sham 12 h,24 hgroup,the concentration of cTnI in serum,and pathological scores of myocardial tissue increased gradually（P〈0.05）in the CLP 12 hand 24 hgroup.Compared to the CLP 12 h,24 hgroup,in the CLP＋ NaHS12 h,24 hgroup,the concentration of cTnI in serum,and pathological scores of myocardial tissue,the expression of NF-κB,the level of TNF-αdecreased and the expression of CSE mRNA and the level of IL-10 increased（P〈0.05）;in the CLP ＋ PAG 12 h,24 hgroup,the concentration of cTnI in serum,and pathological scores of myocardial tissue,the expression of NF-κB,the level of TNF-αincreased gradually（P〈0.05）;and the expression of CSE mRNA and the level of IL-10 increased（P〈0.05）.Conclusion H2 S plays a protective role in sepsisinduced myocardial injury,and the possible mechanism of this protective effect maybe by inhibiting the expression of NF-κB,reducing the content of TNF-αand improving the content of IL-10 in myocardial tissue.