Experimental Study On Citrate Acid To Prevent Diabetic-Induced Cardiac Damage In Mice

Purpose:Cardiovascular complications induced by Diabetes mellitus are the leading cause of mortality in diabetic patients, and with the diabetic cardiomyopathy being one of the most concerned. Many studies have shown that oxidative and nitrative stresses, mediated by reactive oxygen and nitrogen species(ROS and RNS) respectively, are important contributors to cardiac remodeling and abnormal function characteristic of diabetes. Higher levels of cellular reactive oxygen species is important in reducing cellular energy charge(EC) by increasing the levels of key metabolic protein, and nitrosative modifications, and have been shown to damage the cardiac tissue of diabetic mice. However, the relation between energy production and heart function is unclear. Citrate, an intermediate in the TCA cycle, was used to try to increase energy charge in diabetic mice hearts and explain the relationship between energy produced and diabetic heart damage. Methods:Streptozotocin(STZ, 150 mg/kg body weight) was injected intraperitoneally once to mice that had been fasted overnight for induction of diabetes. After diabetic induction, mice received citrate(5 ?g/kg) through intraperitoneal injection every other day for 5 weeks. The caspase-3, plasminogen activator inhibitor 1(PAI1), protein kinase B(PKB), commonly known as AKT and phosphorylated-AKT(p-AKT) proteins were examined to elucidate inflammation and apoptosis in the heart. For histological analysis, heart samples were fixed with 10% formalin and stained with hematoxylin-eosin(HE) and Sirius red to assess pathological changes and fibrosis. The expression levels of marker proteins, tyrosine nitration, activity of ATP synthase and succinyl-CoA:3-ketoacid coenzyme A transferase-1(SCOT), and EC were measured. Results:Intraperitoneal injection of citrate significantly reduced caspase-3 and PAI-1 protein levels and increased p-AKT level on the 5th week; EC in the heart was found to be increased as well. Further, the expression level, activity, and tyrosine nitration of ATP synthase and SCOT were not affected after induction of diabetes. Conclusions:Results indicate that application of citrate, a tricarboxylic acid(TCA) cycle intermediate, might alleviate cardiac dysfunction by reducing cardiac inflammation, apoptosis, and increasing cardiac EC.