Diet-induced obese mouse hearts tolerate an acute high fatty acid exposure that also increases ischemic tolerance.

Diet-induced obese mouse hearts tolerate an acute high fatty acid exposure that also increases ischemic tolerance. Am J Physiol Heart Circ Physiol. 2020 Aug 14;: Authors: Boardman NT, Pedersen TM, Rossvoll L, Hafstad AD, Aasum E Abstract An ischemic insult is accompanied by an acute increase in circulating fatty acid (FA), which can induce adverse changes related to cardiac metabolism/energetics. Although chronic hyperlipidemia contributes to the pathogenesis of obesity/diabetes-related cardiomyopathy, it unclear how these hearts are affected by an acute high FA-load. We hypothesize that adaptation to chronic FA exposure enhances the obese hearts' ability to handle an acute high FA-load. Diet-induced obese (DIO) and age-matched control (CON) mouse hearts were perfused in the presence of low or high FA-load (0.4 and 1.8 mM). Left ventricular (LV) function, FA oxidation rate, myocardial oxygen consumption and mechanical efficiency were assessed, followed by analysis of myocardial oxidative stress, mitochondrial respiration, protein acetylation as well as gene expression. Finally, ischemic tolerance was determined by examining LV functional recovery and infarct size. Under low FA conditions, DIO hearts showed mild LV dysfunction, oxygen wasting, mechanical inefficiency, and reduced mitochondrial OxPhos. High FA-load increased FA oxidation rates in both groups, but this did not alter any of the above parameters in DIO hearts. In contrast...
Source: American Journal of Physiology. Heart and Circulatory Physiology - Category: Physiology Authors: Tags: Am J Physiol Heart Circ Physiol Source Type: research