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目的:研究组蛋白去乙酰化酶沉默信息调节因子1 （silent information regulator 1，SIRT）对心肌缺血再灌注介导的心肌细胞焦亡的影响及相关机制。研究对象:选择95只SD雄性大鼠，体重250-300 g，其中80只采用随机数字表法分为5组：假手术组、模型组、SIRT1高表达组、SIRT1低表达组和单磷酸腺苷激活的蛋白激酶（adenosine monophosphate-activated protein kinase，AMPK）信号通路抑制组，每组16只；另15只大鼠采用随机数字表法分为3组：对照组，SIRT1高表达组和SIRT1低表达组，每组5只。干预措施:80只大鼠每组处理方法如下：（1）假手术组：仅开胸暴露心脏，不做心肌缺血再灌注处理；（2）模型组：心肌内注射空白载体慢病毒7 d后，构建心肌缺血再灌注模型；（3）SIRT1高表达组：心肌内注射SIRT1高表达慢病毒7 d后，构建心肌缺血再灌注模型；（4）SIRT1低表达组：心肌内注射SIRT1小干扰RNA (small interfering RNA，siRNA）表达慢病毒7 d后，构建心肌缺血再灌注模型；（5）AMPK信号通路抑制组：心肌内注射SIRT1高表达慢病毒7 d后，给予AMPK信号通路抑制剂compound C，构建心肌缺血再灌注模型。SD大鼠麻醉后，通过慢病毒注射技术，按每只老鼠1×10n 7 TU/ 30 μl的量，将空白载体慢病毒、过表达SIRT1慢病毒或SIRT1 siRNA慢病毒，在左心室前壁分别取5个部位进行心肌注射。在注射慢病毒后第7天，阻断左前降支冠状动脉40 min再松开120 min，构建心肌缺血再灌注模型。另外15只大鼠用于检测SIRT1慢病毒感染效率，分为：（1）对照组：心肌注射空白载体慢病毒7 d；（2）SIRT1高表达组：心肌内注射SIRT1高表达慢病毒7 d；（3）SIRT1低表达组：心肌内注射SIRT1 siRNA表达慢病毒7 d。n 观测指标与测量方法:待构建模型后对大鼠行安乐死，取缺血区心肌组织，采用生化检测以评价血清心肌酶活性；采用Westernblot法检测焦亡相关蛋白核苷酸结合寡聚化结构域样受体蛋白3 (nucleotide-binding oligomerization domain-like receptor protein 3，NLRP3）、凋亡相关斑点样蛋白（apoptosis-associated speck-like protein containing a caspase activation and recruitment domain，ASC）、炎性半胱天蛋白酶（caspase）-1 P10、白细胞介素-1β （interleukin-1β，IL-1β）的表达，以及AMPK信号通路活性；另取缺血区组织做病理切片，采用TUNEL法检测心肌细胞凋亡率。采用SPSS 22. 0统计软件进行统计学分析，表达量的数值统计用均数±标准差（n ±s）表示，组间对比采用独立样本n t检验，n P<0. 05为差异有统计学意义。柱状图使用Graph Pad Prism 7制作。n 结果:与模型组相比，SIRT1高表达组CK-MB [（961. 64± 11.62）n vs．（1 400. 32± 16.16），n P<0. 05]、乳酸脱氢酶（lactate dehydrogenase, LDH）[（974. 46± 69.58）n vs．（1 752. 97± 99.62），n P<0. 05]水平明显降低；心肌细胞凋亡率显著减少[（30. 06± 6.10）n vs．（69.36± 3.66），n P<0.05]；焦亡相关蛋白NLRP3 [（4. 60±0. 83）n vs．（7. 58±0.77），n P<0. 05]、ASC [（2. 90± 0.19）n vs．（5. 28± 0. 59），n P <0. 05]、caspase-1 P10 [（3.19±0. 20） n vs．（5. 06± 1.01），n P<0. 05]及IL-1β [（5. 05± 0.19）n vs．（8. 32± 0.85），n P<0.05]蛋白表达大量下降；AMPK通路活性增加[（3. 49± 1.05）n vs．（0. 76± 0.02），n P<0. 05]；与SIRT1组比较，AM PK信号通路抑制组CK-MB [（1 568. 28±121.34）n vs．（932. 79± 11.27），n P <0.0 5]及LDH [（1 930. 75± 95.79） n vs．（956. 41± 102. 83），n P<0. 05]水平明显升高；心肌细胞凋亡率显著增加[（69.70± 2.52）n vs．（29.28± 7. 03），n P<0. 05]。n 结论:组蛋白去乙酰化酶SIRT1通过调控AMPK信号通路活性，降低焦亡相关因子的蛋白表达，缓解心肌缺血再灌注损伤。“,”Objective:To investigate the effects and mechanism of the histone deacetylase silent information regulator 1 (SIRT1) on pyroptosis mediated by myocardial ischemia-reperfusion.Subjects:Ninty-five male Sprague Dawley (SD) rats, weighing 250-300 g, and eighty of them were randomly assigned to five groups: sham surgery group, model group, high SIRT1 expression (SIRT1n +) group, low SIRT1 expression (SIRT1n -) group, and adenosine monophosphate-activated protein kinase (AMPK) pathway inhibition group (n n=16 rats per group).The other fifteen rats were randomly assigned to three groups: control group, high SIRT1 expression (SIRT1n +) group, low SIRT1 expression (SIRT1n -) group (n n=5 rats per group).n Interventions:Sham surgery group: thoracotomy was conducted to expose the heart, but myocardial ischemia-reperfusion was not performed. Model group: lentiviruses carrying an empty vector were injected intramyocardially, followed by the induction of myocardial ischemia-reperfusion 7 days later. SIRT1n + group: lentiviruses carrying the SIRT1 gene were injected intramyocardially, followed by the induction of myocardial ischemia-reperfusion 7 days later. SIRT1n -group: lentiviruses carrying small interfering RNAs (siRNAs) targeting SIRT1 were injected intramyocardially, followed by the induction of myocardial ischemia-reperfusion 7 days later. AMPK pathway inhibition group: lentiviruses carrying the SIRT1 gene were injected intramyocardially, followed by treatment with compound C, an AMPK pathway inhibitor, and the induction of myocardial ischemia-reperfusion 7 days later.n Main Outcomes and Measurements:The rats were euthanized after model construction. Ischemic myocardial tissue was collected, and the activity of serum myocardial enzymes was measured via biochemical testing. Western blot analysis was employed to examine the expression levels of pyroptosis-associated proteins, including nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein containing a caspase activation and recruitment domain (ASC), caspase-1 P10, and interleukin-1β (IL-1β), as well as the activity of the AMPK signaling pathway. Pathological sections of the ischemic tissue were also prepared, and the TUNEL assay was performed to measure the apoptotic rate of cardiomyocytes. Statistical analysis was conducted using the SPSS 22.0 software. The expression levels are presented as the mean ± standard deviation (Mean±SD). Between-group comparisons were performed using the independent samplesn t-test. n P values<0.05 were considered statistically significant. The GraphPad Prism 7 software was used to plot histograms.n Results:Compared with the model group, the SIRT1+ group exhibited significantly reduced expression of creatine kinase-MB (CK-MB) [(961.64±11.62) n vs.(1 400.32±16.16), n P<0.05)] and lactate dehydrogenase (LDH)[(974.46±69.58)n vs. (1 752.97±99.62), n P<0.05), and a significantly reduced rate of apoptotic cardiomyocytes [(30.06±6.10)n vs. (69.36±3.66), n P<0.05]. The SIRT1n + group also showed significant decreases in the expression of pyroptosis-related proteins, including NLRP3 [(4.60±0.83) n vs. (7.58±0.77), n P<0.05), ASC[(2.90±0.19)n vs. (5.28±0.59), n P<0.05)], caspase-1 P10[(3.19±0.20)n vs. (5.06±1.01), n P<0.05], and IL-1β [(5.05±0.91)n vs. (8.32±0.85), n P<0.05], while the activity of the AMPK pathway was increased[(3.49±1.05)n vs. (0.76±0.02), n P<0.05]. Compared with the SIRT1n + group, the AMPK pathway inhibition group exhibited significantly elevated expression of CK-MB [(1 568.28±121.34) n vs. (932.79±11.27), n P<0.05] and LDH [(1 930.75±95.79)n vs. (956.41±102.83), n P<0.05)], the apoptotic rate of cardiomyocytes also increased significantly [(69.70±2.52)n vs. (29.28±7.03), n P<0.05].n Conclusion:The histone deacetylase SIRT1 reduces the expression of pyroptosis-associated proteins via the regulation of the AMPK signaling pathway, thereby alleviating myocardial ischemia-reperfusion injury.