Trypanosoma brucei: Infection in murine diabetes

The course of infection due to Trypanosoma brucei infection was observed in genetically diabetic and streptozotocin-induced diabetic mice. A strain of T. brucei, TREU 667, was used which produces a chronic infection in C57BL 6(B6) mice lasting greater than 60 days. Genetic diabetic mice ( +db +db) are obese, and have elevated blood glucose levels, normal levels of insulin, and impaired cell-mediated immunity. Their littermates ( m+ m+, m+ +db) are of normal weight, and are normoglycemic and immunocompetent. The infected +db +db mice lived significantly longer than the nondiabetic littermates. In contrast to this finding, streptozotocin-induced diabetic B6 mice developed higher parasitemia and had shorter survival times than control B6 mice. Continuous treatment with insulin of these streptozotocininduced diabetic mice led to normalization of blood glucose and a significant reduction of parasitemia. While hyperglycemia may be associated with higher parasitemia and death in streptozotozin-induced diabetes, genetic factors may play an additional role in the genetic models.