Abstract

Eman M Fahmy*, Alaa M Abu Seif, Hammoda H Sharaf, Amin YAwad, and Hassan M El-kotby

ABSTRACT

Aims: Streptozotocin is a well-known diabetogenic agent. We aimed to investigate two methods for induction of diabetes mellitus (DM) in rats using streptozotocin (SZT). Methods: 36 male albino rats were categorized into 3 groups (12 rats each). Group I (normal control): no SZT given. Group II: fed on high fat diet (HFD) composed of 22% fat, 48% carbohydrate and 20% protein, for four weeks, then diabetes is induced using two small SZT doses 30 mg/kg with one week interval. Group III: fed on regular diet (RD) composed of 5% fat, 53% carbohydrate and 23% protein, for four weeks, then diabetes is induced using single large SZT dose 60 mg/kg. After 72 hours of induction of diabetes, fasting blood glucose is measured and rats were euthanized and pancreatic specimens were collected for morphometric histological analysis. Results: Compared to the normal control, rats of group II showed increased blood glucose (346%, p < 0.001) with reduction in reactive beta cells (58%, p < 0.001) and reduction in the average area of the islets of Langerhans (33%, p < 0.001). Rats of group III showed increased blood glucose (456%, p < 0.001) with reduction in reactive beta cells (83%, p < 0.001) and reduction in the average area of the islets (77%, p < 0.001). Conclusions: Establishing a rat model for T1DM differs than that for T2DM. Induction of diabetes using two small SZT doses 30 mg/kg in rats fed on HFD produces hyperglycemia and beta cell changes that is more similar to type 2 diabetes. While, using single large SZT dose 60 mg/kg in rats fed on RD produces hyperglycemia and beta cell changes that mimics type 1 diabetes.