Hypercholesterolemia and chronic ischemia alter myocardial responses to selective cyclooxygenase-2 inhibition.

Abstract

OBJECTIVE:

Cyclooxygenase-2 inhibitors have been implicated in adverse cardiac events. We hypothesize that hypercholesterolemia and ischemia may alter the myocardial response to the cyclooxygenase-2 inhibitor celecoxib.

METHODS:

Yorkshire swine fed normal chow (CX, n = 6) or high-cholesterol diet (HCX, n = 6) underwent placement of an Ameroid constrictor on the left circumflex artery and were started on celecoxib (200 mg/day). After 7 weeks, ischemic and nonischemic myocardium was analyzed for thrombogenic ratio (thromboxane content divided by prostacyclin content), total protein oxidative stress, and expression of prostacyclin synthase, thromboxane synthase, myeloperoxidase, and superoxide dismutase. Cardiac function, tissue perfusion, and vessel density were measured.

RESULTS:

HCX animals were significantly hypercholesterolemic compared with CX animals. Thrombogenic ratio was significantly higher in the HCX group than in the CX group, but prostacyclin and thromboxane synthase expression was similar in all tissues. Myocardial perfusion was decreased in the HCX group compared with the CX group. Total oxidative stress, myeloperoxidase, and superoxide dismutase were increased in ischemic tissue compared with nonischemic tissues, but there was no diet-induced difference between groups. There was no difference in capillary or arteriolar density between groups. Left ventricular contractility was greater in the HCX group than in the CX group, but there was no significant difference in heart rate, mean arterial pressure, or left ventricular pressure.

CONCLUSIONS:

Hypercholesterolemic patients using celecoxib may be at higher risk for thrombotic events than those with normal cholesterol, but the relationship between dyslipidemia, ischemia, and cyclooxygenase-2 inhibition is likely much more complicated than originally thought.

• Authors: Louis M Chu, Michael P Robich, Antonio Lassaletta, Thomas Burgess, Yuhong Liu, Nicholas Sellke, Frank W Sellke
• Journal: The Journal of thoracic and cardiovascular surgery (J Thorac Cardiovasc Surg) Vol. 142 Issue 3 Pg. 675-81 (Sep 2011) ISSN: 1097-685X [Electronic] United States
• PMID: 21762932 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)
• Copyright: Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Chemical References

• Cyclooxygenase 2 Inhibitors
• Pyrazoles
• Sulfonamides
• Thromboxanes
• Epoprostenol
• Celecoxib

Topics

• Animals
• Celecoxib
• Comorbidity
• Cyclooxygenase 2 Inhibitors (pharmacology)
• Epoprostenol (metabolism)
• Heart (drug effects)
• Hemodynamics (drug effects)
• Humans
• Hypercholesterolemia (epidemiology, physiopathology)
• Immunohistochemistry
• Myocardial Contraction (drug effects)
• Myocardial Ischemia (epidemiology, physiopathology)
• Oxidative Stress (drug effects)
• Pyrazoles (pharmacology)
• Sulfonamides (pharmacology)
• Swine
• Swine, Miniature
• Thromboxanes (metabolism)
• Ventricular Function, Left (drug effects)