Cellular distribution of free cholesterol was assessed by Filipin staining. Results: LAMP-2 pancreatic levels dramatically decreased in all 3 models of pancreatitis ...
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Proteases are major mediators of inflammation. Cathepsins are cysteine proteases that contribute to pancreatitis by processing trypsinogen within acinar cells (cathepsin B, L), and secreted cathepsins cause inflammation and pain by incompletely understood mechanisms (cathepsin S). However, the spectrum of cathepsins that are activated in pancreatitis is not defined, and their contribution to disease remains to be determined. Methods and Results. Since proteases are regulated by post-translational control of activity, we used an activity-based probe (ABP) that covalently binds to active proteases to detect activated cathepsins. GB123 has an acyloxymethyl ketone reactive “warhead” that targets the active site of cysteine cathepsins and a Cy5.5 tag for detection. GB123 interacted with purified cathepsin B, L and S, as determined by SDS-PAGE and gel fluorescence analysis. The cathepsin inhibitor K11777 abolished this interaction, confirming that GB123 binds to active cathepsins. To identify cathepsins that are activated in the inflamed pancreas, C57/Bl6 mice were treated with cerulein or vehicle (12 hourly injections, 50 μg/kg SQ) to induce acute pancreatitis. Mice then received GB123 (25nmol/mouse IV) and were studied 24 h later. Reflectance imaging of the excised pancreas revealed a 5-fold increase in the Cy5.5 signal in mice with pancreatitis (p=18 years) over a seven-year period, from 1/02 to 12/08, who underwent colonoscopy for the indication hematochezia. We characterized and compared age-stratified LGIB cohorts by patient demographics, disease co-morbidity severity, GI practice setting, endoscopic diagnosis, reported extent of examination, and adverse procedural events. Results: We identified n=76,928 persons who underwent colonoscopy for hematochezia, n=29,376 (38.2%) in the older age cohort. As compared to the younger LGIB patients, the older age cohort had significantly more females (44.9% vs 41.7%) and White non-Hispanics 85.4% vs 79.6% (p
