加味桃核承气汤对糖尿病心肌病大鼠NLRP3炎症小体的影响

Effect of Modified Taohe Chengqitang on NLRP3 Inflammasomes in Rats with Diabetic Cardiomyopathy

目的:探讨加味桃核承气汤对糖尿病心肌病大鼠NOD样受体蛋白3(NLRP3)炎症小体激活的影响。方法:选取3~4周龄SPF级雄性SD大鼠,随机分为正常组和造模组。造模组大鼠采用高脂饲料喂养4周后,给予链脲佐菌素(STZ)腹腔注射(35 mg·kg^(-1))制备糖尿病大鼠模型,再按照空腹血糖随机分为模型组、加味桃核承气汤低、高剂量组(11.7、23.4 g·kg^(-1))、盐酸二甲双胍组(67.5 mg·kg^(-1))。各组连续灌胃给药8周后经超声成像平台检测大鼠心脏功能及结构。股动脉取血检测大鼠空腹血糖(FBG)、甘油三酯(TC)、总胆固醇(TG);苏木素-伊红(HE)染色观察大鼠心肌病理形态学改变;酶联免疫吸附测定法(ELISA)检测大鼠血清白细胞介素^(-1)β(IL^(-1)β)及白细胞介素^(-1)8(IL^(-1)8)水平;蛋白免疫印迹法(Western blot)检测心肌组织NLRP3、ASC、Caspase^(-1)、p-NF-κB p65蛋白表达的影响。结果:与正常组比较,模型组大鼠FBG、TC、TG水平显著升高(P<0.01),左室射血分数(EF)、左室短轴缩短率(FS)明显降低(P<0.05),HE染色可见心肌细胞肥大、心肌纤维化,血清中IL^(-1)β、IL^(-1)8含量及心肌组织NLRP3、ASC、Caspase^(-1)、p-NF-κB p65蛋白表达均显著增高(P<0.01)。与模型组比较,加味桃核承气汤低、高剂量组及二甲双胍组可有效降低大鼠FBG、TC、TG水平(P<0.05),EF、FS均明显改善(P<0.05),大鼠心肌组织病理学损伤明显改善,同时血清IL^(-1)β、IL^(-1)8含量及心肌组织NLRP3、ASC、Caspase^(-1)、p-NF-κB p65蛋白表达均明显降低(P<0.05),其中加味桃核承气汤高剂量组改善更明显。结论:桃核承气汤加味可通过抑制NLRP3炎症小体激活从而发挥保护心肌作用。

Objective:To investigate the effect of modified Taohe Chengqitang on NOD-like receptor protein 3(NLRP3)inflammasome activation in rats with diabetic cardiomyopathy.Method:SPF male SD rats aged 3-4 weeks were randomly divided into a normal group and an experimental group.The rats in the experimental group were fed on a high-fat diet for 4 weeks and then received intraperitoneal injection of streptozotocin(STZ)at 35 mg·kg^(-1) to induce the diabetes model.The rats in the experimental group were randomly divided into model group,low-and high-dose modified Taohe Chengqitang groups(11.7 g·kg^(-1) and 23.4 g·kg^(-1)),and metformin hydrochloride group(67.5 mg·kg^(-1))according to the fast blood glucose(FBG).The cardiac function and structure of rats were detected by ultrasonic imaging after 8 weeks of continuous intragastric administration.Blood samples from the femoral artery were collected to detect FBG,triglyceride(TC),and total cholesterol(TG)of rats.Hematoxylin-eosin(HE)staining was used to observe the pathological changes in rat myocardium.Serum levels of interleukin^(-1)β(IL^(-1)β)and interleukin^(-1)8(IL^(-1)8)were determined by enzyme-linked immunosorbent assay(ELISA).The protein expression of NLRP3,apoptosis-associated speck-like protein containing a CARD(ASC),cysteinyl aspartate-specific protease 1(Caspase^(-1)),and phosphorylated nuclear factor kappa-B p65(p-NF-κB p65)in the myocardium was detected by Western blot.Result:Compared with the normal group,the model group showed increased levels of FBG,TC,and TG(P<0.01),decreased left ventricular ejection fraction(EF)and left ventricular fractional shortening(FS)(P<0.05),myocardial hypertrophy and myocardial fibrosis as revealed by HE staining,increased serum levels of 1L^(-1)βand 1L^(-1)8 and protein expression of NLRP3,ASC,Caspase^(-1),and p-NF-κB p65 in myocardial tissues(P<0.01).Compared with the model group,the modified Taohe Chengqitang groups and the metformin group showed reduced levels of FBG,TC,and TG(P<0.05),restored EF and FS(P<0.05),improved pathological changes in myocardial tissues,and decreased serum levels of IL^(-1)βand IL^(-1)8 and protein expression of NLRP3,ASC,Caspase^(-1),and p-NF-κB p65 in myocardial tissues(P<0.05).The improvement was more significant in the high-dose modified Taohe Chengqitang group(P<0.05).Conclusion:Modified Taohe Chengqitang can protect the myocardium by inhibiting the activation of NLRP3 inflammasomes.