应变技术用于检出肥胖小鼠心肌损伤及评估皮质抑素减轻该损伤的价值

Value of strain technique for detecting myocardial injury and cortistatin for alleviating myocardial injury in obese mice

目的观察应变技术用于检出肥胖小鼠心肌损伤及皮质抑素减轻该损伤的价值。方法将48只雄性C57BL/6小鼠随机分为肥胖组、皮质抑素组及正常组,每组16只;对肥胖组和皮质抑素组小鼠以高脂饲料饲养、正常组以正常饲料饲养11周,之后对皮质抑素组腹腔注射皮质抑素120μg/(kg·d),对肥胖组和正常组腹腔注射等量生理盐水2周。行心脏超声生物显微镜(UBM)、透射电镜,检测炎症因子表达水平,观察组间差异,评估应变技术检出心脏损伤的效能及皮质抑素对于心脏的保护作用。结果3组小鼠常规心脏超声参数差异均无统计学意义(P均>0.05),而应变参数差异均有统计学意义(P均<0.05);肥胖组各应变参数显著低于皮质抑素组和正常组(P均<0.05)。肥胖组心肌超微结构受损,NOD样受体热蛋白结构域相关蛋白3(NLRP3)、半胱氨酸天冬氨酸特异性蛋白酶-1(Caspase-1)及血清IL-1β水平较皮质抑素组及正常组显著增高(P均<0.05);皮质抑素组心肌超微结构未见明显异常。结论利用应变技术可有效检出肥胖小鼠早期心肌损伤;皮质抑素能有效减轻肥胖小鼠心肌损伤。

Objective To observe the value of strain technique for detecting myocardial injury and cortistatin for alleviating myocardial injury in obese mice.Methods A total of 48 male C57BL/6 mice were randomly divided into obese group,cortistatin group or normal group(each n=16).Mice in obese group and cortistatin group were fed with high-fat diet,while those in normal group were fed with normal diet for 11 weeks.Then mice in cortistatin group were intraperitoneally injected with cortistatin 120μg/(kg·d)for 2 weeks,while those in other 2 groups were injected with the same amount of physiological saline.Cardiac ultrasound biomicroscopy(UBM)and transmission electron microscopy were performed,the expression level of inflammatory factors were tested,and the findings were compared among 3 groups.The efficacy of strain technique for detecting myocardial injury was evaluated,and the cardioprotective effect of cortistatin was observed.Results No significant difference of conventional cardiac ultrasound parameters was found(all P>0.05),while significant differences of strain parameters were detected among 3 groups(all P<0.05).Strain parameters of obese group were significantly lower than those of cortistatin group and normal group(all P<0.05).Myocardial ultrastructures were impaired in obese group compared with those in cortistatin group and normal group,and the expression of NOD-like receptor pyrin domain-containing protein 3(NLRP3),cysteinyl aspartate specific proteinase-1(Caspase-1)and serum IL-1βin obese group were significantly higher than those in cortistatin group and normal group(all P<0.05).Myocardial ultrastructures had no significant abnormalities in cortistatin group.Conclusion The strain technique could effectively detect myocardial injury,and cortistatin could alleviate myocardial injury in obese mice.