Li D, Williams V, Liu L, Chen H, Sawamura T, Romeo F, Mehta JL. Expression of lectin-like oxidized low-density lipoprotein receptors during ischemia-reperfusion and its role in determination of apoptosis and left ventricular dysfunction.
J Am Coll Cardiol 2003;
41:1048-55. [PMID:
12651056 DOI:
10.1016/s0735-1097(02)02966-2]
[Citation(s) in RCA: 86] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES
The goal of this study was to determine the role of lectin-like oxidized low-density lipoprotein receptors (LOX-1), a recently identified oxidized low-density lipoprotein (ox-LDL) receptor, in ischemia-reperfusion injury to the heart.
BACKGROUND
Reactive oxygen species (ROS) released during ischemia-reperfusion oxidize low-density lipoproteins; LOX-1 is upregulated by ox-LDL and ROS, and is involved in cell injury.
METHODS
Anesthetized rats were subjected to left coronary artery ligation for 60 min (n = 10, ischemia group), or ischemia followed by 60 min of reperfusion (n = 30, ischemia-reperfusion group). Rats in the latter group were treated with saline, the LOX-1 blocking antibody JXT21 (10 mg/kg), or nonspecific anti-goat immunoglobulin G (IgG) (10 mg/kg). Ten other rats underwent thoracotomy without coronary ligation (sham control).
RESULTS
Ischemia-reperfusion was associated with an increase in LOX-1 expression, lipid peroxidation and apoptosis, a large infarct area, and a decrease in left ventricular function (all, p < 0.01 vs. sham control and ischemia alone groups). Treatment of rats with LOX-1 antibody prevented ischemia-reperfusion-induced upregulation of LOX-1. Importantly, the LOX-1 antibody reduced apoptosis by 48%, lipid peroxidation by 39%, and myocardial infarct size by 45%, and improved left ventricular function (first derivative of pressure measured over time: -47% to -18%, p < 0.01). Nonspecific IgG had no effect.
CONCLUSIONS
Lectin-like oxidized low-density lipoprotein receptors are upregulated during myocardial ischemia-reperfusion, and appear to be associated with apoptosis, necrosis, and left ventricular functional deterioration.
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