Dynamic aspects of cardiac relaxation
Paul Janssen, Department of Physiology and Cell
Biology
Research in the Janssen lab focuses on aspects of myocardial relaxation. Cardiac relaxation is no longer thought to be a mere passive process that logically follows contraction, but is a highly regulated process, involving interactions between calcium removal systems and mechanical molecular motors. We study relaxation using a minimalized systems approach, in which we have the advantage of working in a sub-organ level model (multicellular trabeculae) that still encompasses all the electrical, biochemical, and contractile functions of the whole heart, yet is small enough to control in vitro while allowing for assessment of intracellular events, such as calcium transients. More than half of the patients suffering from heart failure (which kills more people than all cancers and aids combined) suffer from relaxation disorders, and part of our work is to gain understanding in the molecular events that change during progression to heart failure. Other research areas in the lab are aimed at understanding the role of hydroxyl-radical induced damage to the heart, inotropic therapy using glycolysis intermediates, the role of junction proteins in the heart, and cardiac insufficiency in skeletal muscular dystrophy.