Reversal of type 2 diabetes in mice by products of malaria parasites: I. Effect of inactivated parasites

C57BL/KsJ-db/db and C57BL/KsJ-ob/ob mice are good models for studies on hum an obesity and type 2 diabetes. We have previously shown that infection wit h blood-stage malaria or injection of extracts from malaria-parasitized red blood cells induces hypoglycemia in normal mice and normalizes hyperglycem ia in mice made moderately diabetic by streptozotocin. In the present study , we show that a single intravenous (IV) injection of Formalin-fixed Plasmo dium yoelii YM (FFYM) preparation decreases blood glucose in db/db mice fro m an initial value of 19 mmol/L to a normal value of 7 mmol/L (P < .0001) f or at least 24 hours and reduces food intake, Plasma insulin concentrations in db/db mice were not altered. FFYM was also active in normal and ob/ob m ice, an effect associated with an increase in plasma insulin. Although the rate of weight gain in lean ob/+ and lean db/+ was not altered by this trea tment, there was a significant reduction in weight gain in db/db and ob/ob mice (P <.001). We suggest that malaria-derived molecules, when fully chara cterized, may provide structural information for the development of new age nts for the management of type 2 diabetes. Copyright (C) 2000 by W.B. Saund ers Company.