title: Oral administration of sodium tungstate improves cardiac performance in streptozotocin-induced diabetic rats.
abstract: Normalization of hyperglycemia and hyperlipidemia is an important objective in preventing diabetes-induced cardiac dysfunction. Our study investigated the effects of sodium tungstate on cardiac performance in streptozotocin-induced (STZ) diabetic rats based on its potential antidiabetic and antioxidant activity. Male Wistar rats were made STZ-diabetic and then treated with tungstate in their drinking water for 9 weeks. Body mass, food and fluid intake, plasma glucose, insulin, triglyceride, and free fatty acids levels were measured. At the termination of the study period, an oral glucose tolerance test (OGTT) was performed, and cardiac performance was evaluated using an isolated working heart apparatus. Tungstate-treated STZ-diabetic rats showed a significant reduction in fluid and food intake, plasma glucose, triglycerides, and free fatty acid levels, and improved tolerance to glucose in OGTT, owing to tungstate-mediated enhancement of insulin activity rather than increased insulin levels. Left ventricular pressure development, the rate of contraction (+dP/dT), and the rate of relaxation (-dP/dT) were significantly improved in tungstate-treated diabetic rats. Apart from a decreased rate of body mass gain, no other signs of toxicity or hypoglycemic episodes were observed in tungstate-treated rats. This study extends previous observations on the antidiabetic activities of tungstate, and also reports for the first time the salutary effects in preventing diabetic cardiomyopathy.
authors.affiliation: Division of Pharmacology and Toxicology, The University of British Columbia, Vancouver, BC V6T 1Z3, Canada.
authors.forename: Prabhakara Reddy
authors.initials: PR
authors.lastname: Nagareddy
authors.forename: Harish
authors.initials: H
authors.lastname: Vasudevan
authors.forename: John H
authors.initials: JH
authors.lastname: McNeill
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D009202:Cardiomyopathies / Q000209:etiology / Q000517:prevention & control*; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000188:drug therapy / Q000378:metabolism*; D004326:Drinking / Q000187:drug effects; D004435:Eating / Q000187:drug effects; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005951:Glucose Tolerance Test; D006334:Heart Function Tests; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D007328:Insulin / Q000097:blood / Q000378:metabolism; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D013311:Streptozocin; D014280:Triglycerides / Q000097:blood; D017973:Tungsten Compounds / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D016277:Ventricular Function, Left / Q000187:drug effects
chemical_list: D005230:Fatty Acids, Nonesterified; D007004:Hypoglycemic Agents; D007328:Insulin; D014280:Triglycerides; D017973:Tungsten Compounds; D013311:Streptozocin; C025399:sodium tungstate(VI)