title: Low molecular weight inhibitors of Prolyl Oligopeptidase: a review of compounds patented from 2003 to 2010.
abstract: BACKGROUND
  Prolyl Oligopeptidase (POP) is a serine peptidase that cleaves post-proline bonds in short peptides. Besides the direct hydrolytic regulation function over peptides, neuropeptides and peptide hormones, POP is probably involved in the regulation of the inositol pathway and participates in protein-protein interactions. Experimental data show that POP inhibitors have neuroprotective, anti-amnesic and cognition-enhancing properties. These compounds are considered therapeutic agents of interest for the treatment of cognitive deficits related to neuropsychiatric and neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease. Recent findings pointed to the involvement of POP in angiogenesis, although the exact mechanism is still under study.
  
  
  METHODS
  This review comprises patents and patent applications involving POP inhibitors patented between 2003 and 2010, classified as peptidomimetics, heteroaryl ketones and alkaloids. The binding processes and the mechanisms of inhibition of these inhibitors are also discussed, together with their in vivo effects.
  
  
  CONCLUSIONS
  The major part of the repertory of POP inhibitors derived from systematical modification of the canonical compound benzyloxycarbonyl-prolyl-prolinal (ZPP). Nevertheless, only two of them have progressed into the clinical trials. One possible reason for this failure is the lack of studies concerning pharmacodynamics, pharmacokinetics and toxicity, together with the absence of suitable animal models. Moreover, POP is still not a well-defined therapeutic target. Further studies are required for the elucidation of the biological role of POP and to validate the therapeutic action of inhibitors in cognitive processes. In contrast, the involvement of POP in protein-protein interactions together with the recent evidences in angiogenesis opens alternative approaches to the traditional active site-directed inhibitors, as well as new therapeutic applications.
authors.affiliation: Institute for Research in Biomedicine, Barcelona Science Park, Barcelona, Spain.
authors.forename: Abraham
authors.initials: A
authors.lastname: López
authors.forename: Teresa
authors.initials: T
authors.lastname: Tarragó
authors.forename: Ernest
authors.initials: E
authors.lastname: Giralt
mesh_terms: D000470:Alkaloids / Q000494:pharmacology / Q000627:therapeutic use; D000818:Animals; D016503:Drug Delivery Systems; D015195:Drug Design; D004791:Enzyme Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D007659:Ketones / Q000494:pharmacology / Q000627:therapeutic use; D001523:Mental Disorders / Q000188:drug therapy / Q000503:physiopathology; D019636:Neurodegenerative Diseases / Q000503:physiopathology; D010330:Patents as Topic; D057786:Peptidomimetics / Q000494:pharmacology / Q000627:therapeutic use; D000085822:Prolyl Oligopeptidases; D012697:Serine Endopeptidases / Q000187:drug effects* / Q000378:metabolism
chemical_list: D000470:Alkaloids; D004791:Enzyme Inhibitors; D007659:Ketones; D057786:Peptidomimetics; D012697:Serine Endopeptidases; C000705287:PREPL protein, human; D000085822:Prolyl Oligopeptidases