Episodes
Tuesday Jul 25, 2017
Leucine Metabolism Inhibits Cardiac Glucose Uptake
Tuesday Jul 25, 2017
Tuesday Jul 25, 2017
Does the branch chain amino acid leucine mediate cardiac insulin resistance? Listen as Associate Editor Gary Lopaschuk (University of Alberta) interviews lead author Luc Bertrand (Université Catholique de Louvain) and content expert Ravichandran Ramasamy (NYU Langone Medical Center) about the recent work by Renguet et al which investigated whether leucine is simply a biomarker of type 2 diabetes or a factor of the metabolic inflexibility which is a hallmark of type 2 diabetes pathogenesis. Bertrand and colleagues showed that the inhibitory reaction of leucine and ketone bodies in glucose transport requires an increase in protein acetylation, which then contributes to the inhibition of cardiac glucose uptake by hampering the translocation of glucose transporter 4 (GLUT4) to the plasma membrane. This new study by Bertrand and colleagues may be “a new piece in the complex puzzle of cardiac insulin resistance.” Listen and learn more.
Edith Renguet, Audrey Ginion, Roselle Gélinas, Laurent Bultot, Julien Auquier, Isabelle Robillard Frayne, Caroline Daneault, Jean-Louis Vanoverschelde, Christine Des Rosiers, Louis Hue, Sandrine Horman, Christophe Beauloye, Luc Bertrand Metabolism and acetylation contribute to leucine-mediated inhibition of cardiac glucose uptake Am J Physiol Heart Circ Physiol, published online June 23, 2017. DOI: 10.1152/ajpheart.00738.2016
Thursday Jul 20, 2017
β-AR Stimulation and Alternans in Border Zone Cardiomyocytes
Thursday Jul 20, 2017
Thursday Jul 20, 2017
Are calcium alternans in the post-MI border zone more susceptible to the effects of sympathetic stimulation than in normal zone cardiomyocytes? In this podcast Consulting Editor Crystal Ripplinger uncovers the answer in her interview with lead author Jordi Heijman and content expert Thomas Hund about the recent work by Tomek et al. Heijman and co-authors explored sympathetic stimulation and its role in arrhythmogenesis by applying an innovative computational model to the canine post-MI border zone. Did Heijman and colleagues find that β-adrenergic stimulation suppressed alternans by one single mechanism or via multiple pathways? Did Heijman and co-authors also find that hyperinnervation in the border zone is actually anti-arrhythmic, by preventing alternans? Listen and find out.
Jakub Tomek, Blanca Rodriguez, Gil Bub, Jordi Heijman β-adrenergic receptor stimulation inhibits proarrhythmic alternans in post-infarction border zone cardiomyocytes: a computational analysis Am J Physiol Heart Circ Physiol, published online May 26, 2017. DOI: 10.1152/ajpheart.00094.2017