One of the hallmarks of type 2 diabetes (T2D) is an inadequate number of functional pancreatic beta cells that results in insufficient insulin leading to hyperglycemia. Our preliminary work using various mouse models identified a novel target, menin, which can be modulated to stimulate beta cell regeneration and reverse established hyperglycemia in diabetic mice. We are developing a novel small molecule T2D therapeutic to enhance endogenous beta cell regeneration in T2D patients by inhibiting menin. Menin functions in a histone methyltransferase protein complex (menin complex) and by disrupting menin from binding to its partner MLL (mixed lineage leukemia-1) in the complex, this leads to an increase in beta cell proliferation. Recent x-ray crystallography work carried out by Dr. Hua and collaborators revealed a potentially druggable pocket in the co-crystal structure of menin bound to a short MLL peptide. Two promising small molecule compounds (CDH1- 2) that may disrupt the menin/MLL interaction have been identified using our recently developed fluorescence- polarization assay (FP). Novapeutics proposes to advance these promising T2D therapeutics through the following specific aims: (1) Determine the impact of the identified lead compounds (CDH1-2) on beta cell proliferation and expression of cyclin dependent kinase inhibitors CDKI p18ink4c and p27cip1 in treated cells. (2) Optimize and synthesize improved compounds based on the structure of lead compounds via molecular docking in silico to the crystal structure of menin. The chemical information from the identified lead compounds and the menin-MLL X-ray crystal structure will be used for in silico computational analysis to further design and synthesize improved lead derivatives, with higher affinity and greater specificity. Through in silico analysis, the newly designed derivatives will be synthesized and then tested using fluorescence-polarization assay, if the compound disrupts the menin/FITC-labeled MLL peptide interaction and results in a change in fluorescence signal, then it is next subjected to th cellular proliferation assay. Simultaneously, a structural-analysis relationship (SAR) database will be compiled in order to systematically improve lead compounds'design for further optimization. By improving our lead compounds'biochemical profile, hopefully similar improvement will also be seen in both cellular (in SBIR Phase I) and animal experiments (in SBIR Phase II). Through future improved optimized compounds identified from Phase I, we will further refine our lead compounds through medicinal chemistry for use in the T2D therapy. Ultimately, the refined lead compounds should be able to increase endogenous beta cell mass and the function of beta cells, normalizing hyperglycemia and reversing diabetes. These compounds will represent a new class of anti-diabetic drugs, orally administered, negating the need for repeated injections of exogenous insulin in the 17 million US patients diagnosed with T2D.
Type 2 diabetes (T2D) is a serious disease with multiple debilitating complications that can often lead to death. The International Diabetes Federation estimated that more than 285 million people world-wide have diabetes and 438 million people will have this disease within 20 years. We propose the development of a new drug which may allow T2D patients'own insulin producing cells to regenerate and produce adequate amounts of insulin for treating T2D.
