Suchergebnisse

Trehalose analogues bearing fluorescent and click chemistry tags have been developed as probes of bacterial trehalose metabolism, but these tools have limitations with respect to in vivo imaging applications. Here, we report the radiosynthesis of the F-18-modified trehalose analogue 2-deoxy-2-[F-18]fluoro-D-trehalose ([F-18]-2-FDTre), which in principle can be used in conjunction with positron emission tomography (PET) imaging to allow in vivo imaging of trehalose metabolism in various contexts. A chemoenzymatic method employing the thermophilic TreT enzyme from Thermoproteus tenax was used to rapidly (15-20 min), efficiently (70% radiochemical yield; >= 95% radiochemical purity), and reproducibly convert the commercially available radiotracer 2-deoxy-2-[F-18]fluoro-D-glucose ([F-18]-2-FDG) into the target radioprobe [F-18]-2-FDTre in a single step; both manual and automated syntheses were performed with similar results. Cellular uptake experiments showed that radiosynthetic [F-18]-2-FDTre was metabolized by Mycobacterium smegmatis but not by various mammalian cell lines, pointing to the potential future use of this radioprobe for selective PET imaging of infections caused by trehalose-metabolizing bacterial pathogens such as M. tuberculosis. ; This work was funded by a grant from the National Institutes of Health, United States (R15 AI117670) to B.M.S. and P.J.W., as well as a Henry Dreyfus Teacher-Scholar Award from The Camille & Henry Dreyfus Foundation to B.M.S. (TH-17-034). A.Y.-T.H was supported by the Mount Holyoke College Lynk program. Dr. Wenyan Xu is thanked for assistance with kinetic analysis. The research leading to these results received funding from the Innovative Medicines Initiative, European Union (www.imi.europa.eu) Joint Undertaking under grant agreement no. 115337, whose resources comprise funding from EU FP7/2007-2013 and EFPIA, European Union companies in-kind contribution. This work was partially supported by the Ministry of Economy and Competitiveness, Spain TEC2015-73064-EXP and TEC2016-78052-R, ISCIII-FIS grants PI16/02037, co-financed by ERDF, European Union (FEDER) Funds from the European Commission, European Union, "A way of making Europe".

Abstract
The matrix metalloproteinase MMP14 is a ubiquitously expressed, membrane-bound, secreted endopeptidase that proteolyzes substrates to regulate development, signaling, and metabolism. However, the spatial and contextual events inciting MMP14 activation and its metabolic sequelae are not fully understood. Here, we introduce an inducible, hepatocyte-specific MMP14-deficient model (MMP14LKO mice) to elucidate cell-intrinsic and systemic MMP14 function. We show that hepatocyte MMP14 mediates diet-induced body weight gain, peripheral adiposity, and impaired glucose homeostasis and drives diet-induced liver triglyceride accumulation and induction of hepatic inflammatory and fibrotic gene expression. Single-nucleus RNA sequencing revealed that hepatocyte MMP14 mediates Kupffer cell and T-cell accumulation and promotes diet-induced hepatocellular subpopulation shifts toward protection against lipid absorption. MMP14 co-immunoprecipitation and proteomic analyses revealed MMP14 substrate binding across both inflammatory and cytokine signaling, as well as metabolic pathways. Strikingly, hepatocyte MMP14 loss-of-function suppressed skeletal muscle and adipose inflammation in vivo, and in a reductionist adipose–hepatocyte co-culture model. Finally, we reveal that trehalose-type glucose transporter inhibitors decrease hepatocyte MMP14 gene expression and nominate these inhibitors as translatable therapeutic metabolic agents. We conclude that hepatocyte MMP14 drives liver and inter-organ inflammatory and metabolic sequelae of obesogenic dietary insult. Modulating MMP14 activation and blockade thus represents a targetable node in the pathogenesis of hepatic inflammation.