摘要
目的 基于环磷酸鸟苷-腺苷合成酶(cGAS)-干扰素基因刺激因子(STING)信号通路探讨雪莲注射液对小鼠心肌缺血再灌注损伤(MIRI)的保护作用.方法 选40只SPF级雄性C57BL/6小鼠为研究对象,取10只作为假手术组,仅开胸但不结扎冠状动脉,其余30只制备MI-RI模型,造模成功后按随机数字表法分为模型组、雪莲组和RU.521组.雪莲组给予4.11 mg/kg的雪莲注射液腹腔注射,RU.521组给予5 mg/kg的RU.521腹腔注射,假手术组与模型组腹腔注射与雪莲组等体积的0.9％氯化钠注射液.治疗7 d后,采用超声心动图检测左室舒张末期容积(LVEDV)、左室收缩末期容积(LVESV)、左室射血分数(LVEF)、左室短轴缩短率(LVFS),苏木素-伊红(HE)染色观察心肌组织病理形态,末端脱氧核苷酸转移酶介导的缺口末端标记(TUNEL)法测定心肌细胞凋亡指数(AI),比色法测定肌酸激酶(CK)浓度,微板法检测乳酸脱氢酶(LDH)含量,酶联免疫吸附(ELISA)法检测白细胞介素(IL)-6、肿瘤坏死因子(TNF)-α水平,蛋白免疫印迹(WB)法检测cGAS、STING和B淋巴细胞瘤-2基因(Bcl-2)、Bcl-2相关X蛋白(Bax)表达.结果 与假手术组比较,模型组 CK、LDH、IL-6、TNF-α、cGAS、STING、Bax、Bax/Bcl-2、AI、LV-EDV、LVESV 均显著升高(P＜0.01 或P＜0.05),Bcl-2、LVEF、LVFS 明显降低(P＜0.01 或P＜0.05),且心肌组织间隙增宽、排列紊乱伴炎性细胞浸润.与模型组相比,雪莲组和RU.521组的 CK、LDH、IL-6、TNF-α、cGAS、STING、Bax、Bax/Bcl-2、AI、LVEDV、LVESV 均显著下降(P＜0.01 或 P＜0.05),Bcl-2、LVEF、LVFS 明显上升(P＜0.01 或 P＜0.05),且心肌组织的病理性损伤亦减轻.结论 雪莲注射液对小鼠MIRI具有保护作用,其机制可能与cGAS-STING信号通路的抑制有关.
Abstract
Objective To observe the protective effect of Xuelian injectionon myocardial ischemia-reperfu-sion injury(MIRI)in mice based on cyclic guanosine monophosphate-adenosine monophosphate synthase(cGAS)-stimulator of interferon genes(STING)signaling pathway.Methods 40 SPF male C57BL/6 mice were selected as study objects,10 mice were selected as sham group,and only underwent thoracoto-my without coronary artery ligation,the remaining 30 mice were successfully established MIRI model and randomly divided into model group,Xuelian group and RU.521 group with 10 mice per group.Xuelian group was injected intraperitoneally with Xuelian injection at a dose of 4.11 mg/kg,RU.521 group was in-jected intraperitoneally with RU.521 injection at a dose of 5 mg/kg,and the sham group and model group were injected intraperitoneally with 0.9％sodium chloride injection in the same volume as Xuelian group.After 7 days of the treatment,the levels of left ventricular end-diastolic volume(LVEDV),left ventricu-lar end-systolic volume(LVESV),left ventricular ejection fraction(LVEF)and left ventricular fractional shortening(LVFS)were measured by using echocardiography.The pathological morphology of myocardi-al tissue was observed by haematoxylin-eosin(HE)staining.Cardiomyocyte apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling(TUNEL).Lactate dehydrogenase(LDH)content was measured by microplate method,and creatine kinase(CK)concentration was deter-mined by colorimetric method.Interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)levels were de-tected by enzyme linked immunosorbent assay(ELISA).The expressions of cGAS,STING,B cell lym-phoma(Bcl)-2 and Bcl-2-associated X protein(Bax)were detected by Western blotting.Results Com-pared with sham group,the concentrations of CK,LDH,IL-6 and TNF-α,the expression of cGAS,STING,Bax and Bax/Bcl-2 ratio,the levels of AI,LVEDV and LVESV were increased significantly(P＜0.01 or P＜0.05),while the expression of Bcl-2 and the levels of LVEF and LVFS was decreased signifi-cantly in the model group(P＜0.01 or P＜0.05),along with widened interstitium,disordered arrange-ment and inflammatory cells infiltration in the myocardial tissue.Compared with model group,the con-centrations of CK,LDH,IL-6 and TNF-α,the expression of cGAS,STING,Bax and Bax/Bcl-2 ratio,the levels of Al,LVEDV and LVESV was decreased significantly(P＜0.01 or P＜0.05),while the expres-sion of Bcl-2 and the levels of LVEF and LVFS were increased significantly in Xuelian group and RU.521 group(P＜0.01 or P＜0.05),and the myocardial histopathological damage was reduced.Conclusion Xuelian injection has a protective effect on MIRI,and the mechanism may be related to the inhibition of cGAS-STING signaling pathway.
维普
万方数据