Abstract
Background: The prevalence of obesity and related chronic diseases, among them noninsulin- dependent (type 2) diabetes mellitus, are on the rise in the United States and throughout the world. Animal models are useful for investigating the outcome and development of diabetes. Objective: We evaluated the Nile rat, an exotic African rodent, as a potential laboratory animal model for type 2 diabetes mellitus. Design: Data from our compiled data base was examined for body weight, food and water consumption, blood glucose levels and the prevalence of diabetes according to age and gender. Blood insulin concentrations, Insulin Tolerance Test, Glucose Tolerance Test, triglycerides, lipoproteins and liver lipids were assessed from individual studies to establish the nature of the diabetes. Results: The Nile rat demonstrated classical signs of non-insulin-dependent (type 2) diabetes mellitus with an increased food and water intake, rising blood glucose with impaired glucose clearance, and abnormalities in both insulin secretion and blood insulin concentration that were associated with age. In addition, plasma triglycerides, VLDL-C, LDL-C and liver lipids rose as diabetes developed. Surprisingly, no correlation was found between increasing blood glucose levels and body mass index (adiposity), even under the extreme conditions of caloric restriction. Conclusion: The Nile rat appears to be a suitable model for diabetes research, including development of type 2 diabetes and the use of diet modification to impact progression of the disease.