title: Proteomic approach to study the effects of various oxidatively modified low-density lipoprotein on regulation of protein expression in human umbilical vein endothelial cell.
abstract: Circulating low-density lipoprotein (LDL) isolated by our laboratory, a new form of modified LDL and designated as L5, has been reported to be cytotoxic by inducing apoptosis of vascular endothelial cells in vitro. The objective of this study was to compare the biological functions of three different forms of oxidatively modified LDL on human umbilical vein endothelial cells (HUVEC) by proteomic approaches. HUVEC were incubated with serum-free medium, native LDL (N-LDL), L5 isolated from familial hypercholesterolemic subjects (FH-L5), copper-oxidized LDL (Cu-ox-LDL), and atheroma-derived LDL (a-LDL) at 37 degrees C for 24 h. We found that HUVEC incubated with FH-L5 expressed approximately 3 fold higher concentration of MCP-1 than did cells subject to other treatments. All modified LDL significantly suppressed ATP synthase, Grp58, Grp78, and Prdx3. However, the expression of hnRNP C1/C2 was significantly enhanced by FH-L5 and a-LDL; glutathione transferase was significantly enhanced only by FH-L5. A concordant pattern of protein expression was observed between immunoblotting and 2D electrophoresis. Different forms of oxidatively modified LDL regulated HUVEC protein expression in different patterns, suggesting different roles for different oxLDL forms in inducing atherogenesis.
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Ching-Yi
authors.initials: CY
authors.lastname: Chen
authors.forename: Chii-Ming
authors.initials: CM
authors.lastname: Lee
authors.forename: Hsiu-Ching
authors.initials: HC
authors.lastname: Hsu
authors.forename: Chao-Yuh
authors.initials: CY
authors.lastname: Yang
authors.forename: Lu-Ping
authors.initials: LP
authors.lastname: Chow
authors.forename: Yuan-Teh
authors.initials: YT
authors.lastname: Lee
mesh_terms: D015180:Electrophoresis, Gel, Two-Dimensional; D000091342:Endoplasmic Reticulum Chaperone BiP; D042783:Endothelial Cells / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D015151:Immunoblotting; D008077:Lipoproteins, LDL / Q000494:pharmacology*; D013058:Mass Spectrometry; D011506:Proteins / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D014471:Umbilical Veins / Q000166:cytology* / Q000378:metabolism
chemical_list: D000091342:Endoplasmic Reticulum Chaperone BiP; C000717247:HSPA5 protein, human; D008077:Lipoproteins, LDL; D011506:Proteins