Study On The Mechanism Of HUVECs Apoptosis Induced By High Density Lipoprotein In Patients With Premature Coronary Heart Disease

Objective:In vitro experimental study,we aim to research whether there are differences in high density lipoprotein(HDL)which was isolated from patients with premature coronary heart disease(HDLPCAD)against human umbilical vein endothelial cells(HUVECs)apoptosis compare to HDL which was isolated from healthy subjects(HDLhealth).Methods:1.Blood samples of PCAD patients and healthy subjects were collected;2.sub-fraction(HDL1-HDL10)distribution of the HDLhealth and HDLPCAD were analyzed using Lipoprint System;3.HDL was isolated from the blood samples of PCAD patients and healthy subjects,and then extraction and identification of HDL;4.HUVECs was treatmented 24 hours with 0?g/ml?50?g/ml?100?g/ml?150?g/ml?200?g/ml oxidized low density lipoprotein(ox-LDL),cell viability was detected useing MTT,to identify the appropriate concentration of ox-LDL induce HUVECs cell apoptosis;5.HUVECs was pretreatmented with different concentration(0?g/ml?50?g/ml?100?g/ml?150?g/ml?200?g/ml)of HDLhealth,then treatmented with the appropriate concentration of ox-LDL for 24 hours,cell viability was detected useing MTT,to identify the optimal concentration of HDLhealth pretreatmented HUVECs;6.HUVECs was pretreatmented different hours(0h?6h?12h?18h?24h)with HDLhealth,then treatmented with the appropriate concentration of ox-LDL for 24 hours,cell viability was detected useing MTT,to identify the optimal time of HDLhealth pretreatmented HUVECs;7.HUVECs was pretreatmented with the optimal hours useing the optimal concentration of HDLhealth and HDLPCAD,then treatmented with the appropriate concentration of ox-LDL for 24 hours,cell viability was detected useing MTT;cell apoptosis was detected useing flow cytometry staining;Caspase-3?caspase-9 proteinexpressions were detectioned using Western blot;The activity of reactive oxygen species(ROS)was detectioned using kit;Results:1.The large particles(HDL1-HDL3)content of the HDLPCAD sub-fraction are(28.5 +5.74),which is lower than that of HDLhealth(46.8 + 15.2),while the small particles(HDL8-HDL10)content are(21.4 + 7.75),which is higher than that of HDLhealth(10.9 + 5.38)2.The HUVECs survival rate was 60.34% after treatmented with 100?g/ml ox-LDL for 24 hours,and compared with the control group,the survival rate was significantly lower(P < 0.05);3.The HUVECs survival rate was 82.01% after pretreatmented with 200?g/ml HDLhealth for 18 hours,which can significantly reduce the damage of ox-LDL on the cell;4.200?g/ml HDLhealth significantly inhibit apoptosis of HUVECs ?expression of caspase-3?caspase-9,and significantly inhibit the production of ROS,which were induced by 100?g/ml ox-LDL;5.The HUVECs survival rate was65.5% after pretreatmented with 200?g/ml HDLPCAD for 18 hours,and its effect was weaker than that of HDLhealth(80.28%);6.200?g/ml HDLPCAD can inhibit apoptosis of HUVECs?expression of caspase-3?caspase-9 and ROS induced by 100?g/ml ox-LDL,but the effect is weaker than that of HDLhealth.Conclusion:Comparison to the HDLhealth,perhaps due to the large particle of HDLPCAD sub-fraction content(HDL1-HDL3)was lower than that of HDLhealth,while the small particles were higher than that of HDLhealth(HDL8-HDL10),resulting in antioxidant function weakened,inhibiting the apoptosis of endothelial cells induced by ox-LDL were decreased,thereby weakening or the loss of the role of anti AS.