High density lipoprotein-induced angiogenesis requires the activation of Ras/MAP kinase in human coronary artery endothelial cells.
OBJECTIVE
Plasma high density lipoprotein (HDL) levels have been shown to be inversely correlated with coronary artery disease, but the mechanisms of the direct protective effect of HDL on endothelial cells (ECs) are not fully understood. In this study, we investigated the role of the HDL-mediated promotion of angiogenesis in human coronary artery ECs (HCECs).


RESULTS
We developed an in vitro model of HCEC tube formation on a matrix gel. We optimized the maximum dose of HDL required to induce tube formation in initial experiments, in which the dose response showed that the maximum effective dose of HDL was 100 microg/mL. PD98059, an inhibitor of p42/44 mitogen-activated protein kinase (MAPK) activity, but not SB203580, an inhibitor of p38 MAPK activity, suppressed HDL-induced tube formation. Dominant-negative Ras N17 inhibited HDL-induced tube formation. HDL activated Ras according to a ras pull-down assay, and this effect was inhibited by pertussis toxin. Moreover, HDL activated phospho(p)-p42/44 MAPK, whereas Ras N17 blocked HDL-induced pp42/44 MAPK.


CONCLUSIONS
These results indicate that HDL induced a potent signal through a Ras/MAPK pathway mediated by a pertussis toxin-sensitive G-protein coupled receptor to the angiogenic phenotype in HCECs.
Miura
Shin-ichiro
S
Department of Cardiology, Fukuoka University School of Medicine, 7-45-1 Nanakuma, Jonan-Ku, Fukuoka, 814-0180, Japan. miuras@cis.fukuoka-u.ac.jp
Fujino
Masahiro
M
Matsuo
Yoshino
Y
Kawamura
Akira
A
Tanigawa
Hiroyuki
H
Nishikawa
Hiroaki
H
Saku
Keijiro
K
D002478:Cells, Cultured / Q000187:drug effects / Q000201:enzymology; D003331:Coronary Vessels / Q000166:cytology*; D042783:Endothelial Cells / Q000187:drug effects* / Q000201:enzymology; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D008075:Lipoproteins, HDL / Q000494:pharmacology*; D020935:MAP Kinase Signaling System; D019950:Mitogen-Activated Protein Kinase 1 / Q000502:physiology*; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000502:physiology*; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D037342:Pertussis Toxin / Q000494:pharmacology; D016283:Proto-Oncogene Proteins p21(ras) / Q000502:physiology*; D011725:Pyridines / Q000494:pharmacology; D048051:p38 Mitogen-Activated Protein Kinases
D004791:Enzyme Inhibitors; D005419:Flavonoids; D007093:Imidazoles; D008075:Lipoproteins, HDL; D011725:Pyridines; D037342:Pertussis Toxin; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; C501009:HRAS protein, human; D016283:Proto-Oncogene Proteins p21(ras); C093642:SB 203580; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one