The study on the effect of neuregulin-1 on myocardial injury in septic rats / 重庆医学

ABSTRACT

Objective To study the effect of neuromodulatory protein-1(NRG-1)in inhibiting sepsis induced myocardial injury and its mechanism.Methods The rat sepsis model was established by cecal ligation and puncture(CLP).SD rats were divided into the sham operation group,sepsis group,sepsis+NRG group(rhNRG,10 μg/kg).After 12,24 h of successful modeling,the heart and peripheral serum of the surviving rats in each group were taken respectively.The HE staining was used to observe the changes of cardiac tissue morphology and structure,and ELISA was used to detect the expression levels of creatine kinase(CK),crea-tine kinase MB isoenzyme(CK-MB),sensitive troponin Ⅰ(cTnⅠ)in serum,tumor necrosis factor-α(TNF-α)in cardiac tissue and IL-6 expression level;Western blot was used to detect the phosphorylation protein ki-nase B(p-Akt),phosphorylation glycogen synthase kinaseβ(p-GSK3β),B-cell lymphoma/leukemia-2(Bcl-2)and Bax protein expression in rat myocardial tissue.Results After 12,24 h of modeling,compared with the sham group,the expression levels of CK,CK-MB and cTnⅠ in serum,TNF-α,IL-6 and Bax protein in myocar-dial tissue in the sepsis group all were significantly increased(P＜0.05),while the expression levels of p-Akt and p-GSK3β in myocardial tissue were significantly decreased(P＜0.05).After 12,24 h of modeling,com-pared with the sepsis group,the expression levels of CK,CK-MB,cTn Ⅰ in the serum and the expression levels of TNF-α,IL-6 in the myocardial tissue of the sepsis+NRG group were significantly decreased;after 24 h of modeling,compared with the sepsis group,the expression level of Bax protein in myocardial tissue of the sep-sis+NRG group was decreased,while the p-Akt,p-GSK3β expression levels were increased(P＜0.05).The pathological results showed that compared with the sham operation group,the sepsis group produced signifi-cant lesions;compared with the sepsis group,the lesions in the sepsis+NRG group were alleviated.Conclusion The expression levels of related biomarkers in septic myocardial injury have change.NRG-1 could improve the cardiac function through Akt/GSK3β pathway,inhibit the related proinflammatory factors and reduce the myocardial tissue damage.