Effect Of Glycated LDL On The Proliferation And The Expression Of ICAM-1 And VWF Of HUVECs

Objective To observe the effect of LDL_D on the proliferation, the secretion of sICAM-1 and vWF, and the expression of ICAM-1, vWF mRNA of HUVECs in vitro, in order to elucidate the mechanism of LDL_D in angiopathy in diabetes mellitus.Methods HUVECs were obtained through the enzyme dissociation method. LDL was isolated from the serum of diabetes patients and normal volunteers. Hence LDL was nominated LDLd and LDLn respectively. Experiments were allocated into 3 groups: the LDL_D group, LDL_N group and the control group. The effect of LDLd on the proliferation of HUVEC was observed through MTT, the effect on the secretion of sICAM-1, vWF was evaluated by the method of ELISA. And the effect of LDLd on expression of ICAM-1, vWF mRNA was quantified through RT-PCR.Results According to MTT, LDLd showed dose-dependent and time-dependent inhibition on the proliferation of HUVEC. The OD value of LDL_D 50, LDL_D 100, LDL_D 150, LDL_D 200 and LDL_D 500 was 0.606±0.068, 0.442±0.117, 0.382±0.066, 0.276±0.059, 0.122±0.041 respectively. Compared to the control group 0.724±0.096, the OD value of LDL_D100, LDL_D 150, LDL_D 200 and LDL_D 500 was lower, difference is significant (P<0.01). The OD value of LDL_D Oh, 12h, 24h and 36h group was 0. 676±0. 041, 0. 683±0. 028, 0. 614±0. 030 and 0. 491±0. 075. Compared to LDL_D Oh, the OD value of LDL_D 24h and 36h group were lower, difference is significant (P<0.05). The secretion of sICAM-1 and vWF in LDL_D group is significantly higher than that in LDLn group (P<0.05). Further study showed LDL_D promoted vWF secretion in a dose-dependent way, and the level of vWF increased significantly according to the rise of the concentration of LDL_D. Furthermore, LDL_D stimulated ICAM-1 mRNA expression. In the group of LDL_D 12h,24h and 36h, ICAM-1 mRNA was 0.448±0.025, 0.528±0.024 and 0.675±0.019. Compared to LDL_N 12h 0.365±0.012 , LDL_D12h,24h and 36h is significantly higher (P<0.05) . vWF mRNA of LDL_D 12h, 24h and 36h group was 0.504±0.052, 0.605±0.109 and 0.653±0.049 respectively. Compared to LDL_d 12h, LDL_d 24h and 36h is higher, difference is significant (P<0.01). At the same point of time, vWF mRNA expression in LDL_D group is significantly higher than that in LDL_N group (P<0.05) .Conclusion Glycated LDL inhibited the proliferation of HUVECs, stimulated HUVECs to secrete sICAM-1 and vWF, and increased ICAM-1 and vWF mRNA expression. These results implied that LDL_D played an important role in the mechanism of atherosclerosis in Diabetes Mellitus.