Ontology highlight
ABSTRACT: Objective
Fibroblast activation protein (FAP) is a serine protease belonging to a S9B prolyl oligopeptidase subfamily. This enzyme has been implicated in cancer development and recently reported to regulate degradation of FGF21, a potent metabolic hormone. Using a known FAP inhibitor, talabostat (TB), we explored the impact of FAP inhibition on metabolic regulation in mice.Methods
To address this question we evaluated the pharmacology of TB in various mouse models including those deficient in FGF21, GLP1 and GIP signaling. We also studied the ability of FAP to process FGF21 in vitro and TB to block FAP enzymatic activity.Results
TB administration to diet-induced obese (DIO) animals led to profound decreases in body weight, reduced food consumption and adiposity, increased energy expenditure, improved glucose tolerance and insulin sensitivity, and lowered cholesterol levels. Total and intact plasma FGF21 were observed to be elevated in TB-treated DIO mice but not lean animals where the metabolic impact of TB was significantly attenuated. Furthermore, and in stark contrast to naïve DIO mice, the administration of TB to obese FGF21 knockout animals demonstrated no appreciable effect on body weight or any other measures of metabolism. In support of these results we observed no enzymatic degradation of human FGF21 at either end of the protein when FAP was inhibited in vitro by TB.Conclusions
We conclude that pharmacological inhibition of FAP enhances levels of FGF21 in obese mice to provide robust metabolic benefits not observed in lean animals, thus validating this enzyme as a novel drug target for the treatment of obesity and diabetes.
SUBMITTER: Sanchez-Garrido MA
PROVIDER: S-EPMC5034526 | biostudies-literature | 2016 Oct
REPOSITORIES: biostudies-literature
Sánchez-Garrido Miguel Angel MA Habegger Kirk M KM Clemmensen Christoffer C Holleman Cassie C Müller Timo D TD Perez-Tilve Diego D Li Pengyun P Agrawal Archita S AS Finan Brian B Drucker Daniel J DJ Tschöp Matthias H MH DiMarchi Richard D RD Kharitonenkov Alexei A
Molecular metabolism 20160716 10
<h4>Objective</h4>Fibroblast activation protein (FAP) is a serine protease belonging to a S9B prolyl oligopeptidase subfamily. This enzyme has been implicated in cancer development and recently reported to regulate degradation of FGF21, a potent metabolic hormone. Using a known FAP inhibitor, talabostat (TB), we explored the impact of FAP inhibition on metabolic regulation in mice.<h4>Methods</h4>To address this question we evaluated the pharmacology of TB in various mouse models including those ...[more]