13 research outputs found
Effect of insulin and diet on the steady state concentrations of intermediates of the pentose phosphate pathway of glucose metabolism in liver
Thyroid hormone control of cyclic nucleotide phosphodiesterases and the regulation of the sensitivity of the liver to hormones
Calculation of the intracellular distribution of acetyl CoA and CoA, based on the use of citrate synthase as an equilibrium enzyme
Effect of insulin and diet on the steady state concentrations of intermediates of the pentose phosphate pathway of glucose metabolism in liver
Constant and specific proportion groups of enzymes in rat mammary gland and adipose tissue in relation to lipogenesis
Transient and steady state concentrations of the intermediates of the pentose phosphate pathway in Krebs ascites tumour cells metabolising glucose
Modulation of rat pancreatic islet cell replication and insulin release by glibenclamide
The changes of metabolite content and the control of phosphofructokinase in rat liver in different dietary and hormonal conditions
Reversal of type 2 diabetes in mice by products of malaria parasites. II. Role of inositol phosphoglycans (IPGs).
We have previously shown that infection with Plasmodium yoelii malaria or injection of extracts from malaria-parasitized red cells induces hypoglycemia in normal mice and normalizes the hyperglycemia in mice made moderately diabetic with streptozotocin. Inositol phosphoglycans (IPGs) are released outside cells by hydrolysis of membrane-bound glycosylphosphatidylinositols (GPIs), and act as second messengers mediating insulin action. The C57BL/Ks-db/db and C57BL/6J-ob/ob mice offer good models for studies on human obesity and Type 2 diabetes. In the present study, we show that a single iv injection of IPG-A or IPG-P extracted from P. yoelii significantly (P < 0.02) lowers the blood glucose in STZ-diabetic, db/db, and in ob/ob mice for at least 4--6 h. Using rat white adipocytes, IPG-P increased lipogenesis by 20--30% in the presence and absence of maximal concentrations of insulin (10(-8) M) (P < 0.01) and stimulated pyruvate dehydrogenase (PDH) phosphatase in a dose-related manner. Both IPG-A and IPG-P inhibited c-AMP-dependent protein kinase (PKA) in a dose-related manner. Compositional analysis of IPGs after 24 h hydrolysis revealed the presence of myo-inositol, phosphorus, galactosamine, glucosamine, and glucose in both IPG-A and IPG-P. However, hydrolysis of IPGs for 4 h highlighted differences between IPG-A and IPG-P. There are some functional similarities between P. yoelii IPGs and those previously described for mammalian liver. However, this is the first report of the hypoglycemic effect of IPGs in murine models of Type 2 diabetes. We suggest that IPGs isolated from P. yoelii, when fully characterized, may provide structural information for the synthesis of new drugs for the management of diabetes mellitus