The Metal Chelators, Trientine and Citrate, Inhibit the Development of Cardiac Pathology in the Zucker Diabetic Rat

PURPOSE The objective of this study was to determine the efficacy of dietary supplementation with the metal chelators, trientine or citric acid, in preventing the development of cardiomyopathy in the Zucker diabetic rat. HYPOTHESIS We hypothesized that dietary chelators would attenuate metal-catalyzed oxidative stress and damage in tissues and protect against pathological changes in ventricular structure and function in type II diabetes. METHODS Animals (10 weeks old) included lean control (LC, fa/+), untreated Zucker diabetic fatty (ZDF, fa/fa), and ZDF rats treated with either trientine (triethylenetetramine) or citrate at 20 mg/d in drinking water, starting when rats were frankly diabetic. Cardiac functional assessment was determined using a Millar pressure/volume catheter placed in the left ventricle at 32 weeks of age. RESULTS End diastolic volume for the ZDF animals increased by 36% indicating LV dilatation (P < .05) and was accompanied by a 30% increase in the end diastolic pressure (P <or= .05). Both trientine and citric acid prevented the increases in EDV and EDP (P < .05). Ejection fraction and myocardial relaxation were also significantly improved with chelator treatment. CONCLUSION Dietary supplementation with trientine and citric acid significantly prevented structural and functional changes in the diabetic heart, supporting the merits of mild chelators for prevention of cardiovascular disease in diabetes.