丹皮酚对脓毒症小鼠心肌炎的保护作用及机制研究

Study on the protective effect and mechanism of paeonol on myocarditis in sepsis mice

目的探讨丹皮酚对脂多糖诱导的脓毒症小鼠心肌炎的保护抗炎作用。方法30只雄性C57/bl-6小鼠,随机分5组,每组6只,分别为对照组、模型组(脂多糖)及低剂量、中剂量和高剂量治疗组(脂多糖+丹皮酚)。对照组腹腔注射生理盐水1 mL/kg,其余4组腹腔注射脂多糖10 mg/kg建立脓毒症小鼠模型;之后对照组及模型组每天生理盐水10mL/kg灌胃,治疗组分别灌丹皮酚25、50、100 mg/kg灌胃,连续3 d。检测心肌组织中p-P65、BAX、TNF-α、mTOR的蛋白表达水平。苏木精伊红(HE)染色观察心肌组织心肌纤维肿胀、炎症细胞浸润及凋亡情况。培养心肌细胞H9C2,以1μg/mL的脂多糖诱导心肌细胞建立炎症反应模型,给25、50、100μmol/L的丹皮酚处理,免疫荧光检测p-P65表达。结果与正常对照组相比,模型组TNF-α、BAX、p-P65、mTOR升高(P<0.05);丹皮酚治疗组TNF-α、BAX、p-P65、mTOR下降(P<0.05);高剂量治疗组小鼠明显降低p-P65、BAX、TNF-α、mTOR的蛋白表达水平(P<0.05)。模型组心肌组织胶原纤维多,心肌结构紊乱。与模型组比较,高剂量丹皮酚组使心肌组织结构更接近正常。结论丹皮酚可保护心肌,减轻炎症损伤,其机制可能与mTOR抗凋亡能力有关。

Objective To investigate the protective and anti-inflammatory effects of paeonol(PAE)on lipopolysaccharide(LPS)-induced myocarditis in septic mice.Methods A total of 30 male C57/bl-6 mice were randomly divided into 5 groups,with 6 mice in each group:control group,model group(LPS),and low,medium and high dose treatment groups(LPS+PAE).The control group was intraperitoneally injected with 1 mL/kg normal saline,and the other 4 groups were intraperitoneally injected with 10 mg/kg LPS to establish sepsis mouse models.After that,the control group and the model group were intragastrically administered with normal saline 10 mL/kg every day,while the treatment groups were intragastrically administered with PAE 25,50 and 100 mg/kg for 3 consecutive days,respectively.The protein expression levels of p-P65,BAX,TNF-αand mTOR in myocardial tissue were detected.Hematoxylin-eosin(HE)staining was used to observe myocardial fiber swelling,inflammatory cell infiltration and apoptosis.Cardiomyocytes H9C2 were cultured and induced by LPS of 1μg/mL to establish an inflammatory response model.The cardiomyocytes were treated with PAE of 25,50,100μmol/L.p-P65 expression was detected by immunofluorescence.Results Compared with normal group,TNF-α,BAX,p-P65 and mTOR were increased in model group(P<0.05).In paeonol treatment groups,TNF-α,BAX,p-P65 and mTOR decreased(P<0.05).The protein expression levels of p-P65,BAX,TNF-αand mTOR could be significantly decreased in high-dose treatment group(P<0.05).The myocardium of the model group had more collagen fibers and disordered myocardium structure.Compared with the model group,the high dose paeonol treatment group made the myocardial tissue structure closer to normal.Conclusion Paeonol can protect myocardium and reduce inflammatory damage,and its mechanism may be related to the anti-apoptotic ability of mTOR.