Simultaneous (19)F NMR screening of prolyl oligopeptidase and dipeptidyl peptidase IV inhibitors.

Prolyl oligopeptidase (POP) and dipeptidyl peptidase IV (DPP IV) are serine proteases that belong to the same family of enzymes. These peptidases are relevant because of their association with the pathophysiology of serious illnesses, such as type 2 diabetes (DPP IV), and those related to cognitive disorders (POP). Several NMR-based screening methods are being used to find and validate new hit scaffolds. In particular, (19)F NMR-based screening methods have proven to be powerful tools for the discovery and development of new inhibitors. Here we present an accurate and reliable (19)F NMR-based simultaneous assay that is used to screen for new selective POP and DPP IV inhibitors in compound mixtures. This activity assay consists of the simultaneous performance of POP and DPP-IV (19)F NMR activity assays in the presence of their fluorine-containing substrates. Furthermore, the assays were conducted in the presence of 0.01 % v/v of Triton X-100, which is a detergent that disrupts micelle formation, thereby preventing unspecific aggregate-based inhibition. Finally, this (19)F NMR methodology was applied to screen for ligands in plant extracts. Our results indicate that this method allows the simultaneous and accurate identification of selective POP and DPP IV inhibitors in these compound mixtures.