New glucosidase inhibitors from an ayurvedic herbal treatment for type 2 diabetes: structures and inhibition of human intestinal maltase-glucoamylase with compounds from Salacia reticulata.Sim, L., Jayakanthan, K., Mohan, S., Nasi, R., Johnston, B.D., Pinto, B.M., Rose, D.R.
(2010) Biochemistry 49: 443-451
- PubMed: 20039683
- DOI: 10.1021/bi9016457
- Primary Citation of Related Structures:
- PubMed Abstract:
An approach to controlling blood glucose levels in individuals with type 2 diabetes is to target alpha-amylases and intestinal glucosidases using alpha-glucosidase inhibitors acarbose and miglitol. One of the intestinal glucosidases targeted is the N ...
An approach to controlling blood glucose levels in individuals with type 2 diabetes is to target alpha-amylases and intestinal glucosidases using alpha-glucosidase inhibitors acarbose and miglitol. One of the intestinal glucosidases targeted is the N-terminal catalytic domain of maltase-glucoamylase (ntMGAM), one of the four intestinal glycoside hydrolase 31 enzyme activities responsible for the hydrolysis of terminal starch products into glucose. Here we present the X-ray crystallographic studies of ntMGAM in complex with a new class of alpha-glucosidase inhibitors derived from natural extracts of Salacia reticulata, a plant used traditionally in Ayuverdic medicine for the treatment of type 2 diabetes. Included in these extracts are the active compounds salacinol, kotalanol, and de-O-sulfonated kotalanol. This study reveals that de-O-sulfonated kotalanol is the most potent ntMGAM inhibitor reported to date (K(i) = 0.03 microM), some 2000-fold better than the compounds currently used in the clinic, and highlights the potential of the salacinol class of inhibitors as future drug candidates.
Ontario Cancer Institute and Department of Medical Biophysics, University of Toronto, 101 College Street, Toronto, ON, M5G 1L7 Canada.