Comparison Of Protective Effects Of Shenlian And Shengmaiyin On PM_2.5 Promoting Myocardial Ischemic Injury And Mechanism Research

Backgroud:Fine particulate matter(PM_2.5)is one of the most important environmental risk factor for cardiovascular morbidity and mortality worldwide.The current drug intervention studying on PM_2.5-related cardiovascular disease is still in its infancy.It is of great significance to explore effective interventions to effectively reduce the risk of myocardial ischemic diseases in healthy and high-risk individuals under PM_2.5 exposure conditions.Objective:In the previous study,it was found that Shengmaiyin,Shenlian showed a common protective effect on PM_2.5-induced myocardial ischemic injury.Systematic comparison of the protective effects of two different prescriptions on PM_2.5-induced myocardial ischemic injury,and exploring effective methods for rationally characterizing the advantages and characteristics of its pharmacodynamic effects on providing experimental basis for clinical prevention and treatment of cardiovascular acute events by PM_2.5.Method:SD rats were divided into model group,Shenlian group（SL）,Shengmaiyin group（SM）,and sham operation group.One week before the operation,the drug was administered to the rats.After the last administration,rats were instilled with PM_2.5suspension,and the left anterior descending coronary artery ligation was performed 24hours later to establish a composite model of PM_2.5 promoting myocardial ischemic injury,after 24 hours of ligature:Firstly,myocardial infarct size was detected by TTC staining.Myocardial histopathological morphology was observed by HE staining and transmission electron microscopy.Serum myocardial injury markers（LDH,CK-MB,c Tn T）were detected and the degree of myocardial damage was evaluated.Secondly,HE staining of lung tissue was used to observe the pathological changes of lung tissue and the deposition of particles,and to evaluate the degree of lung tissue damage.Thirdly,to assess the effects of drugs on key pathological aspects of PM_2.5-related cardiovascular injury,serum oxidative damage（T-SOD,GSH-PX,CAT,MDA）,inflammatory damage（TNF-α,IL-6,MCP-1）,blood hypercoagulability status indicators（ATPP,PT,Fib）were detected.Forthly,to evaluate the repair effect of drugs on rat heart function,small animal ultrasound method was used.Fifthly,the effect of organ index on immune organs（thymus,spleen）is evaluated.RT-PCR,Western blot and enzyme-linked immunosorbent assay were used to detect the expression of NLRP3 inflammasome（NLRP3、ASC、Caspase-1）related genes,proteins and downstream IL-1 family cytokines（IL-1β、IL-18、IL-33）in myocardial tissue,and to evaluate the effect of drugs on natural immune function.Immunoturbidimetric assay for serum immunoglobulins（Ig A,Ig G,Ig M,Ig E）to evaluate the repair of acquired immune system.Sixthly,quantitative proteomics method was used to find differentially expressed proteins,and to further explore the characteristics of the two sides and the common rules of action.Result:Both Shenlian and Shengmaiyin could improve the survival rate of rats and significantly reduce the myocardial infarct size（P<0.001,P<0.01）,Shenlian and Shengmaiyin can significantly reduce myocardial necrosis and myocardial fibrosis,inflammatory cell infiltration and mitochondrial damage;Shengmaiyin can also improve lung tissue damage,reduce alveolar epithelial hyperplasia and thicken alveolar wall,reduce inflammatory cell infiltration,and reduce lung particulate matter deposition;Compared with the model group,the levels of LDH,CK-MB and c Tn T in serum of rats were decreased to different degrees（P<0.05 or P<0.001）;Both Shenlian and Shengmaiyin could decrease MDA level（P<0.01,P<0.01）,and increase the activity of T-SOD,GSH-PX and CAT in the serum of rats（P<0.05 or P<0.001 or P>0.05）;Both Shenlian and Shengmaiyin can reduce the levels of IL-6,TNF-αand MCP-1 in serum of rats（P<0.01 or P<0.001 or P>0.05）.In addition,Shenlian can also extend ATPP（P<0.01）.Compared with the model group,Shenlian and Shengmaiyin could slightly increase LVIDS,LVIDD,EF%,and FS%,but there was no statistical difference,and there was no significant improvement in cardiac function.Shenlian and Shengmaiyin have no effect on immune organs.Western blot,PCR and ELISA showed that Shenlian and Shengmaiyin could significantly inhibit the activation of NLRP3 inflammasome and the secretion of related cytokines in the natural immune system（P<0.05 or P<0.01 or P>0.05）;Shenlian and Shengmaiyin have certain effects on the Ig G,Ig G,Ig M and Ig E levels in the serum of rats.Based on proteomics results,a total of 137 proteins were found to be altered in the model group compared to the sham group;Compared with the model group,there were191 differentially expressed proteins in the shengmai group;Compared with the model group,there were 38 differentially expressed proteins in the shenlianfang group.The model group mainly caused changes in the biological processes such as congenital immune response,inflammatory response,complement activation and blood coagulation,which led to the damage of the body,which is basically consistent with the results of the previous experiments.Most of the differentially expressed proteins in the Shengmai group were associated with coagulation/anticoagulation and complement system,and the results of previous pharmacodynamic experiments from intervening inflammation and hypercoagulability and improving innate immune function confirmed the recovery of the Shengmai group.Two proteins（Col1a1,Mt2A）are associated with atherosclerosis.The shenlian group recover proteins（Myl4,Myl7,Mylpf,Col1a1,Coll1a1,Nppa,etc.）are associated with amelioration of pathological processes such as arrhythmia,heart failure,and myocardial fibrosis;It is found that the high-coupling protein involved in the formation of focal adhesions suggests that the adhesion between immune cells,inflammatory cells and endothelial tissues,and between platelets and exposed collagen may be one of the key points of the action of Shenlianfang.Conclusion:（1）PM_2.5 exposure was combined with left anterior descending coronary artery ligation for 24 hours,the myocardial tissue of the model group showed obvious white infarction,and the levels of LDH,CK-MB and c Tn T increased significantly in the serum,pathological examination showed myocardial injury,these prove this experimental model was successfully constructed.（2）Shenlian and Shengmaiyin have protective effects on PM_2.5aggravation of myocardial ischemic injury,which can reduce mortality,reduce myocardial damage,reduce inflammation and improve antioxidant capacity of the body;and there are certain advantages in improving the overall state of model animals,reducing lung tissue damage and reducing particle deposition.Shenlianfang has a certain regulation effect on hypercoagulable state and inflammatory cell chemotaxis.（3）The effects of Shenlian and Shengmaiyin on the improvement of cardiac function in this model were not significant.They both have effects on the NLRP3 inflammasome pathway of the natural immune system.（4）Based on proteomic analysis,Shengmaiyin may protect the myocardium by reducing inflammation,inhibiting the complement coagulation cascade,and regulating the fibrinolytic system;Shenlian may reduce myocardial fibrosis by regulating myocardial collagen synthesis,reduce the adhesion reaction to play a cardioprotective role.