Role for peroxisome proliferator-activated receptor α in oxidized phospholipid–induced synthesis of monocyte chemotactic protein-1 and interleukin-8 by endothelial …

H Lee, W Shi, P Tontonoz, S Wang… - Circulation …, 2000 - Am Heart Assoc
H Lee, W Shi, P Tontonoz, S Wang, G Subbanagounder, CC Hedrick, S Hama, C Borromeo…
Circulation research, 2000Am Heart Assoc
The attraction, binding, and entry of monocytes into the vessel wall play an important role in
atherogenesis. We have previously shown that minimally oxidized/modified LDL (MM-LDL),
a pathogenically relevant lipoprotein, can activate human aortic endothelial cells (HAECs) to
produce monocyte chemotactic activators. In the present study, we demonstrate that MM-
LDL and oxidation products of 1-palmitoyl-2-arachidonyl-sn-glycero-3-phosphocholine
(PAPC) activate endothelial cells to synthesize monocyte chemotactic protein-1 (MCP-1) …
Abstract
—The attraction, binding, and entry of monocytes into the vessel wall play an important role in atherogenesis. We have previously shown that minimally oxidized/modified LDL (MM-LDL), a pathogenically relevant lipoprotein, can activate human aortic endothelial cells (HAECs) to produce monocyte chemotactic activators. In the present study, we demonstrate that MM-LDL and oxidation products of 1-palmitoyl-2-arachidonyl-sn-glycero-3-phosphocholine (PAPC) activate endothelial cells to synthesize monocyte chemotactic protein-1 (MCP-1) and interleukin-8 (IL-8). Several lines of evidence suggest that this activation is mediated by the lipid-dependent transcription factor peroxisome proliferator-activated receptor α (PPARα), the most abundant member of the PPAR family in HAECs. Treatment of transfected CV-1 cells demonstrated activation of the PPARα ligand-binding domain by MM-LDL, Ox-PAPC, or its component phospholipids, 1-palmitoyl-2-oxovalaroyl-sn-glycero-phosphocholine and 1-palmitoyl-2-glutaroyl-sn-glycero-phosphocholine; these lipids also activated a consensus peroxisome proliferator-activated receptor response element (PPRE) in transfected HAECs. Furthermore, activation of PPARα with synthetic ligand Wy14,643 stimulates the synthesis of IL-8 and MCP-1 by HAECs. By contrast, troglitazone, a PPARγ agonist, decreased the levels of IL-8 and MCP-1. Finally, we demonstrate that unlike wild-type endothelial cells, endothelial cells derived from PPARα null mice do not produce MCP-1/JE in response to Ox-PAPC and MM-LDL. Together, these data demonstrate a proinflammatory role for PPARα in mediation of the activation of endothelial cells to produce monocyte chemotactic activity in response to oxidized phospholipids and lipoproteins.
Am Heart Assoc