Grant: Travel Awards - Institute Community Support

The increasing incidence of cardiovascular disease is a major burden on our healthcare system. A critical precursor is the development of insulin resistance (IR) where insulin's ability to stimulate the usage of glucose is impaired. Recent evidence suggests that IR can be a result of suboptimal pregnancy conditions, particularly in situations resulting in babies born of low birth-weight (LBW). Confounding this problem is the readily available western diet (WD, high-fat/high-sugar) in our society. Studies now show the pivotal role a WD plays in the development of IR in liver and heart which subsequently leads to diabetes and heart disease. Additionally cardiac IR is associated with reduced heart size, and impairment of cardiac function. Thus the study of LBW and WD effects on the development of IR in the heart is an important area of research with significant implications. However, despite numerous studies outlining the independent effects of LBW or WD on adult health, the interactions between LBW and WD remain unknown. We postulate that the combination of LBW and WD will exacerbate the development of heart IR. Our objective was to utilize non-invasive imaging techniques to identify physiological changes in the heart associated with IR development. Using a well established model in the guinea pig, we investigated the physiological changes of LBW and WD. Combining with the latest technology in computed tomography (CT) and positron emission tomography (PET), we were able to non-invasively characterize changes blood flow and glucose metabolism in the left ventricle. We demonstrated that guinea pigs born of LBW and fed a WD have a reduced heart blood flow in addition to reduced glucose metabolism. These changes are indicative of an alteration in insulin sensitivity and improper cardiac function. Therefore this leads us to conclude that the combined LBW and WD insults may lead to the exacerbation of the IR deficits, resulting to its expression in early adulthood.