| Objective By replicating the rat model of myocardial ischemia-reperfusion injury,we investigated the effect of mongolian danggong-3 on myocardial ischemia-reperfusion myocardium and the relationship between its protective effect and PI3K/Akt signaling pathway.Methods SD rats were randomly divided into seven groups: blank group(group A),model group(group B),sham operation group(group C),Danggong-3 high dose group(group D),medium dose group(group E),low dose group(group F),Danggong-3 high dose + PI3K/Akt blocker LY294002 group(group G),10 rats in each group,a total of 70 rats.D,E,F and G groups were given Danggong-3 the suspension of 1.08g/kg,0.54g/kg,0.27g/kg,1.08g/kg were gavaged,while groups A,B and C were gavaged with equal amount of distilled water once a day for 21 days;The model was prepared after the end of gavage,G group of rats were injected LY294002(0.3 mg/kg)into the tail vein 10 min before the model was made.Samples were taken after reperfusion,and serum LDH and CK-MB activities were measured by Elisa method;the area of myocardial infarction was determined by Evans Blue and TTC double staining method;the apoptosis index of myocardial cells was detected by TUNEL method;the pathological changes of myocardial tissue were observed by HE staining;PI3K,Akt,Bax,Bcl-2 protein levels in myocardial tissues of rats were measured by Western blot.Results 1.Changes of serum LDH and CK-MB contents in rats: There was no significant change in serum LDH and CK-MB contents in group C compared with group A(P>0.05).The contents of LDH and CK-MB in serum of rats in group B were significantly higher than those in group C(P<0.01).After Danggong-3 intervention,the serum LDH and CK-MB levels of rats in groups D,E and F were significantly lower than those in group B(P<0.01).The contents of LDH and CK-MB in serum of rats in group D were significantly lower than those in groups E and F(P<0.01).The contents of LDH and CK-MB in serum of rats in group G were significantly higher than those in group D(P<0.01).2.Measurement of myocardial infarction area and apoptosis index of rats: There was no significant change in myocardial infarction area and apoptosis index in group C compared with group A(P>0.05).The myocardial infarction area and apoptosis index of rats in group B were significantly higher than those in group C(P<0.01).After Danggong-3 intervention,the myocardial infarction area and apoptosis index of rats in groups D,E and F were significantly lower than those in group B(P<0.01).Myocardial infarct size and apoptosis index in group D were significantly lower than those in groups E and F(P<0.01).The myocardial infarction area and apoptosis index of rats in group G were significantly higher than those in group D(P<0.01).3.HE staining results of rat myocardial tissues: There were no obvious pathological changes in myocardial tissues of rats in groups A and C.In group B,myocardial tissue showed pathological manifestations such as tomography,blurred texture,irregular shape of myocardial fibers and infiltration of a large number of inflammatory cells in the interstitium.After Danggong-3 intervention,the pathological morphology of cardiac tissue in groups D,E and F was improved to a certain extent compared with group B,especially in group D. 4.Protein expression of PI3 K,Akt,Bcl-2 and Bax in rat myocardial tissues: There was no significant change in protein expression of PI3 K,Akt,Bcl-2 and Bax in rat myocardial tissue of group C compared with group A(P>0.05).Compared with group C,the expression of PI3 K,Akt,Bcl-2 protein in myocardial tissue of rats in group B decreased significantly,and the expression of Bax protein increased significantly(P<0.01).After Danggong-3 intervention,compared with group B,PI3 K,Akt,Bcl-2 protein expression in groups D,E and F increased significantly,while Bax protein expression decreased significantly(P<0.01).Compared with the E and F groups,the expression of PI3 K,Akt,Bcl-2 protein in group D increased significantly,while the expression of Bax protein decreased significantly(P<0.01).Compared with group D,the expression of PI3 K,Akt,Bcl-2 protein in group G decreased significantly,and the expression of Bax increased significantly(P<0.01).Conclusion Mongolian medicine Danggong-3 has the function of protecting myocardium during myocardial ischemia and reperfusion,and its mechanism may be related to inhibiting cardiomyocyte apoptosis and activating PI3K/Akt signaling pathway. |
PDF Full Text Request