TRAF3IP2 as a Proinflammatory Mediator of Alcohol-related Cardiomyopathy - Abstract This NRSA F30 fellowship will provide the groundwork that will prepare the applicant for a career in academic medicine as a cardiothoracic anesthesiologist. Much of the applicant’s career development will come from work in alcohol and cardiovascular-related research. Alcohol-related Cardiomyopathy (AC) manifests in humans after excessive alcohol consumption and is characterized by ventricular dilation and cardiac function impairment. During cardiac inflammation and injury, fibroblasts differentiate into myofibroblasts, which are larger in cell size and express higher levels of collagens and their crosslinking enzyme lysyl oxidase (LOX). Here, the role of TRAF3IP2, a proinflammatory cytoplasmic adapter protein, in the pathogenesis of AC is explored. Preliminary data indicates that exposure of naïve cardiac fibroblasts (CF) to alcohol induces TRAF3IP2 protein expression in a time- and dose-dependent manner. In our studies, we will investigate whether i) alcohol-induced cardiac fibroblast activation, and proinflammatory cytokine and extracellular matrix expression are dependent on TRAF3IP2 and ii) global TRAF3IP2 gene deletion prevents alcohol-induced cardiac inflammation, fibrosis, and dysfunction. The cellular mechanism underlying alcohol-induced cardiac inflammation and fibrosis are investigated using both in vitro and in vivo alcohol exposure. In vitro, TRAF3IP2 is targeted using naïve CF from wild-type mice transduced with TRAF3IP2 shRNA and CF isolated from homozygous TRAF3IP2 knockout mice. In vivo, TRAF3IP2 is targeted using global TRAF3IP2- knockout mice on a 30-day Lieber-DeCarli or isocaloric control liquid diet based on the chronic+binge model. Endpoint measures include induction of proinflammatory and profibrotic pathways. Using the chronic+binge model of AC, TRAF3IP2-KO and littermate controls are exposed to chronic alcohol consumption. Endpoints include assessment of cardiac function and chamber dimensions by echocardiography and pressure-volume left ventricular catheterization. Markers of inflammation and fibrotic measures include collagens I and III, LOX expression, left ventricle total collagen, and histological assessment of interstitial fibrosis by PSR staining. Ultimately, these studies may identify novel, therapeutic targets for the treatment of alcohol- related cardiomyopathy. With the support of a strong mentoring team, completion of the proposed research and training plan will ensure that the applicant is prepared for an impactful career as a physician-scientist.
