Advanced-glycation end products (AGEs) derived from glycated albumin suppress early beta1-adrenergic preconditioning

Fundam Clin Pharmacol. 2007 Feb;21(1):35-43. doi: 10.1111/j.1472-8206.2006.00451.x.

Abstract

Ischemic heart disease in diabetic patients might be linked to the accumulation of advanced-glycation end products (AGEs). In ischemic rat hearts, expression of receptor for AGEs and its ligands is significantly enhanced and involved in cardiac ischemia/reperfusion (I/R) injury even in the absence of diabetes. It has recently been reported that diabetic human myocardium cannot be protected by preconditioning. In this context, our hypothesis was that beta1-adrenergic preconditioning might be altered in the presence of AGEs. Using an isolated non-working rat heart model, this study investigated the effect of AGEs on cardioprotection induced by transient beta1-adrenoceptor (beta1-AR) stimulation with xamoterol (Xa). After 6-hydroxydopamine (6-OHDA) pre-treatment and a 20-min stabilization period, hearts were perfused at constant pressure for 20 min, then subjected to 40 min of global ischemia and 30 min of reperfusion (I/R, Ctrl); and exposed to 0.01 microm Xa for 5 min framed with or without 15.2 microm albumin (Alb) or glycated albumin (Gly Alb). The main endpoints were the mean coronary flow (MCF), the left ventricular end-diastolic pressure (LVEDP), rate-pressure product (RPP) and creatine kinase (CK) release and necrosis area. XA induced an increase in the MCF after I/R (t = 85 min), a protective effect on the LVEDP, an improvement in RPP, a decrease of CK release during reperfusion and a reduction of necrotic area. The beneficial effects induced by Xa during reperfusion were suppressed by the administration of Gly Alb during Xa infusion, whereas Alb did not hamper Xa-induced protection. These results suggest that AGEs suppress the cardioprotection resulting from the activation of beta1-ARs and thus might contribute to cardiovascular damages seen in diabetic patients.

MeSH terms

  • Adrenergic beta-1 Receptor Agonists*
  • Adrenergic beta-Agonists*
  • Albumins / pharmacology
  • Animals
  • Blood Pressure / drug effects
  • Coronary Circulation / drug effects
  • Creatine Kinase / metabolism
  • Glycated Serum Albumin
  • Glycation End Products, Advanced / pharmacology
  • Heart / drug effects
  • Heart / physiopathology
  • In Vitro Techniques
  • Ischemic Preconditioning, Myocardial*
  • Male
  • Myocardium / metabolism
  • Myocardium / pathology
  • Rats
  • Rats, Wistar
  • Serum Albumin / pharmacology*
  • Xamoterol*

Substances

  • Adrenergic beta-1 Receptor Agonists
  • Adrenergic beta-Agonists
  • Albumins
  • Glycation End Products, Advanced
  • Serum Albumin
  • Xamoterol
  • Creatine Kinase
  • Glycated Serum Albumin