[MB06322 (CS-917): A potent and selective inhibitor of fructose 1,6-bisphosphatase for controlling gluconeogenesis in type 2 diabetes] PNAS open access article
Published online before print May 23, 2005, 10.1073/pnas.0502983102 MB06322 (CS-917): A potent and selective inhibitor of fructose 1,6-bisphosphatase for controlling gluconeogenesis in type 2 diabetes
Mark D. Erion *, {dagger}, Paul D. van Poelje *, Qun Dang *, Srinivas Rao Kasibhatla *, Scott C. Potter *, M. Rami Reddy *, K. Raja Reddy *, Tao Jiang * and William N. Lipscomb {ddagger}
*Departments of Biochemistry, Medicinal Chemistry, and Molecular Modeling, Metabasis Therapeutics, Inc., 9390 Towne Centre Drive, Building 300, San Diego, CA 92121; and {ddagger}Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138
Contributed by William N. Lipscomb, April 13, 2005
In type 2 diabetes, the liver produces excessive amounts of glucose through the gluconeogenesis (GNG) pathway and consequently is partly responsible for the elevated glucose levels characteristic of the disease. In an effort to find safe and efficacious GNG inhibitors, we targeted the AMP binding site of fructose 1,6-bisphosphatase (FBPase). The hydrophilic nature of AMP binding sites and their widespread use for allosteric regulation of enzymes in metabolic pathways has historically made discovery of AMP mimetics suitable for drug development difficult. By using a structure-based drug design strategy, we discovered a series of compounds that mimic AMP but bear little structural resemblance. The lead compound, MB05032, exhibited high potency and specificity for human FBPase. Oral delivery of MB05032 was achieved by using the bisamidate prodrug MB06322 (CS-917), which is converted to MB05032 in two steps through the action of an esterase and a phosphoramidase. MB06322 inhibited glucose production from a variety of GNG substrates in rat hepatocytes and from bicarbonate in male Zucker diabetic fatty rats. Analysis of liver GNG pathway intermediates confirmed FBPase as the site of action. Oral administration of MB06322 to Zucker diabetic fatty rats led to a dose-dependent decrease in plasma glucose levels independent of insulin levels and nutritional status. Glucose lowering occurred without signs of hypoglycemia or significant elevations in plasma lactate or triglyceride levels. The findings suggest that potent and specific FBPase inhibitors represent a drug class with potential to treat type 2 diabetes through inhibition of GNG.
endogenous glucose production | AMP mimetic | structure-based drug design | phosphonate prodrug | antihyperglycemic
Author contributions: M.D.E., P.D.v.P., and Q.D. designed research; P.D.v.P., Q.D., S.R.K., S.C.P., M.R.R., K.R.R., T.J., and W.N.L. performed research; M.D.E., P.D.v.P., Q.D., S.R.K., S.C.P., M.R.R., K.R.R., T.J., and W.N.L. analyzed data; and M.D.E. wrote the paper.
Freely available online through the PNAS open access option. pnas.org
Abbreviations: GNG, gluconeogenesis; FBPase, fructose 1,6-bisphosphatase; ZDF, Zucker diabetic fatty; T2DM, type 2 diabetes mellitus; FPG, fasting plasma glucose; ZMP, aminoimidazole-4-carboxamide riboside monophosphate; Fru 2,6-P2, fructose 2,6-bisphosphate. |