[Mechanism of inhibition of apoptosis of human umbilical vein endothelial cells induced by oxidized-low density lipoprotein by erythropoietin].
OBJECTIVE
To explore the protective effect of erythropoietin (EPO) against oxidized-low density lipoprotein (ox-LDL)-induced apoptosis in human umbilical vein endothelial cells (HUVECs) in an ox-LDL induced apoptosis model.


METHODS
Third-sixth passage of cultured HUVECs were used, and they were divided into two groups. The cells were pretreated with different concentrations (6.25, 50, 100 kU/L) of recombinant human erythropoietin (rhEPO) for 24 hours, then they were exposed to ox-LDL (100 mg/L) for 48 hours; another group of cells were pretreated with antisense to 0.5 micromol/L LOX-1 mRNA or 0.5 micromol/L sense for 24 hours, and then HUVECs were exposed to ox-LDL (100 mg/L) for 12 hours. Apoptosis was assessed by the apoptosis ratio, cell viability, and Bcl-2/Bax ratio.


RESULTS
As compared to untreated controls, pretreatment with rhEPO led to increased cell survival of HUVECs and decreased cell apoptosis in a dose-dependent manner (all P<0.05). Consistently, the Bcl-2/Bax ratios were also increased in a similar fashion. The ratio of apoptosis protein Bcl-2/Bax was increased in the antisense LOX-1 mRNA group than that of ox-LDL group (P<0.05), but the one in the sense LOX-1 mRNA group was not significantly different from that of ox-LDL group.


CONCLUSIONS
The ox-LDL can induce apoptosis in HUVECs by regulating LOX-1 mRNA, and rhEPO can increase Bcl-2/Bax ratio and inhibit ox-LDL-induced apoptosis of HUVECs.
Yang
Xiao-fang
XF
Department of Cardiology, First Hospital of Lanzhou University, Key Lab of Preclinical Study for New Drugs of Gansu Province, Lanzhou 730000, Gansu, China.
Xiong
Jian-wen
JW
Wang
Zhi-lu
ZL
Li
Yan
Y
Xu
Zhe-tong
ZT
Cui
Li-jun
LJ
Wang
Feng
F
Tan
Li-li
LL
Zhang
Li
L
D017209:Apoptosis / Q000187:drug effects*; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000187:drug effects* / Q000473:pathology; D004730:Endothelium, Vascular / Q000166:cytology; D004921:Erythropoietin / Q000494:pharmacology*; D006801:Humans; D008077:Lipoproteins, LDL / Q000494:pharmacology*; D011994:Recombinant Proteins; D051127:Scavenger Receptors, Class E / Q000378:metabolism; D014471:Umbilical Veins / Q000166:cytology
D008077:Lipoproteins, LDL; C495137:OLR1 protein, human; D011994:Recombinant Proteins; D051127:Scavenger Receptors, Class E; C099252:oxidized low density lipoprotein; D004921:Erythropoietin