Insulin is a phylogenetically old peptide hormone, being present at least in molluscs, insects, and vertebrates. Its functions are related to regulation of energy metabolism and growth.
Hypoglycaemia is a major complication of severe malaria, especially in cerebral malaria where it is associated with increased mortality. In uncomplicated falciparum malaria, glucose production is increased by about 25 %, due to an increase in gluconeogenesis and a simultaneous decrease in glycogenolysis, but hypoglycaemia is mainyl caused by hyperinsulinaemia. If insulin secretion is blocked, hypoglycaemia can be reversed. Glycophosphatidyl inositol membrane anchors of malaria proteins are released as malaria toxic antigens and act synergistically to insulin. They induce production and release of tumour necrosis factor from macrophages, they stimulate lipogenesis and inhibit lipolysis in adipocytes.
Monoclonal antibodies against the glycophosphatidyl inositol of parasite origin can neutralize the toxic effects of parasite extracts.