ABSTRACT
Matrix metalloproteinases (MMPs) are zinc-dependent secreted or transmembrane enzymes constituting a family of over 20 proteolytic members that are capable of selectively digesting a wide spectrum of both extracellular matrix (ECM) and nonmatrix proteins. MMP-1 expression is acutely increased in the rat ischemia reperfusion model following one hour of coronary ligation and one h of reperfusion before tissue analysis. MMP-1 in this model was cardiomyotoxic, and could be linked to myocardial weakening by favoring collagen scar degradation. There are a number of reports on MMP-based imaging agents for imaging MMP expression in tumors. Several synthetic sulfonamide-based MMP inhibitors have been radiolabeled with carbon-11, fluorine-18, or iodine-123; and preliminary evaluations of these radiotracers for tumor imaging have been performed. In a more successful approach, C. Bremer et al. reported on a biocompatible near-infrared fluorogenic MMP substrate that is used as an activatable reporter probe to sense MMP activity.
