Dual roles of oxidized LDL in modulating expression of inflammatory molecules in HUVECs / 中国病理生理杂志

ABSTRACT

AIM: To determine the role of LOX-1/PPAR pathway in regulating expression of adhesion molecules elicited by oxidizing low density lipoprotein(Ox-LDL) through Lectin-like oxidized low-density lipoprotein receptor-1(LOX-1) in human umbilical vein endothelial cells(HUVECs).METHODS: HUVECs were incubated with Ox-LDL,poly(I),carrageenan or 15-deoxy-△12,14-prostaglanding J2(15d-PGJ2).PPAR mRNA and protein were examined by real time RT-PCR and Western blotting.ICAM-1 and E-selectin were detected by RT-PCR and Western blotting respectively.RESULTS: Ox-LDL increased PPAR expression in HUVECs,which was inhibited by pretreatment of HUVECs with LOX-1 blockers.Preincubation of HUVECs with 15d-PGJ2 attenuated the expression of intercellular adhesion molecule-1(ICAM-1) and E-selectin in response to Ox-LDL.Upregulation of ICAM-1 and E-selectin mediated by Ox-LDL were suppressed more significantly by the combination of 15d-PGJ2 and polyinosonic acid as compared to either 15d-PGJ2 or polyinosonic acid alone.CONCLUSION: The results indicate that Ox-LDL exerts a biphasic effects on inflammatory response.It evokes harmful effects by inflammatory injury on one side and protective effects by triggering the LOX-1/ PPAR signaling pathway on the other hand.