Effect And Mechanism Of Melatonin In Regulating Mst1 On Myocardial Microvascular Endothelial Cell Injury In Hypertensive Mice

Objective:To investigate whether melatonin(MT)can protect mouse myocardial microvascular endothelial cells(CMEC)from damage under hypertension by regulating Mst1(Mammalian Sterile20 like Kinase1).Methods:Cultivation of mouse myocardial microvascular endothelial cells using cell recovery,cell passaging and cell freezing methods.The hypertensive cell model was established by intervention of angiotensin II(Ang II)with a concentration of 100 umol/L for 24 hours,and the intervention was repeated with melatonin with a concentration of 1mmol/L.Divided the experiment into seven groups: control group: cardiomyocytes were cultured for 48 h under conventional conditions;hypertension group(HP group): cardiomyocytes were cultured for 24 h under conventional conditions,and Ang II concentration was 100umol/L for 24h;hypertension+negative control group(HP+Ad-NC group): Ang II concentration was 100umol/L for 24h;at the same time,the negative control CON267 adenovirus was infected for 48h;hypertension+Mst1overexpression group(HP+Ad-Mst1 group):Ang II concentration was 100 umol/L for 24 h,48 hours of simultaneous infection with AD-STk4 adenovirus,hypertension+melatonin group(HP+MT group): after 24 hours of routine culture of myocardial cells,melatonin MT(1mmol/L)intervened for 24 hours before Ang II intervention,Ang II concentration 100umol/L intervened for 24 hours,hypertension+negative control group+melatonin(HP+Ad-NC+MT group): melatonin MT(1mmol/L)intervened for 24 hours before Ang II intervention,Ang II concentration100umol/L intervened for 24 hours,and infected negative control CON267 adenovirus for48 hours at the same time,Hypertension+Mst1 overexpression group+melatonin(HP+Ad-Mst1+MT group): melatonin MT(1mmol/L)was intervened for 24 h before Ang II intervention,Ang II with a concentration of 100umol/L was intervened for 24 h,and AD-STk4 adenovirus was infected for 48 h at the same time.The number of autophagic corpuscles was observed by fluoroscopic electron microscopy,the degree of apoptosis was detected by flow cytometry,and the potential level of mitochondrial membrane was measured by JC-1 method.The content of MDA,SOD,and GSH-Px was measured by enzyme-labeled colorimetry.Results:After MT intervention,the number of autophagic bodies increased and autophagy increased.From the results of cell apoptosis and mitochondrial membrane potential,it can be seen that the ratio of apoptosis and JC-1monomer in the HP+MT group is significantly lower than that in the HP group(P<0.05).Compared with the HP+Ad-Mst1 group,the ratio of apoptosis and JC-1 monomer in the HP+Ad-Mst1+MT group is significantly lower(P<0.05).The results of oxidative stress showed that the content of MDA in the HP+MT group was significantly decreased(P<0.05),and the activity levels of SOD and GSH-Px were significantly increased(P<0.05).Compared with the HP+Ad-Mst1 group,the content of MDA in the HP+Ad-Mst1+MT group was significantly decreased(P<0.05),while the activity of SOD and GSH-Px was significantly increased(P<0.05).Conclusion:Melatonin can inhibit the apoptosis of myocardial microvascular cells in hypertensive mice,alleviate the apoptosis caused by the overexpression of Mst1,increase the mitochondrial membrane potential,and inhibit the overexpression of Mst1.The above shows that melatonin can play its myocardial protective role by regulating Mst1.