August 30, 2017
How does cancer cachexia directly affect the heart? Listen as Deputy Editor Merry Lindsey (University of Mississippi Medical Center) tackles this question and more as she interviews lead author Loren Wold (The Ohio State University) and content expert Hemal Patel (VA San Diego Healthcare System, University of California San Diego) about the insightful study by Devine et al on cancer-induced cachexia and its effects on cardiac muscle structure and physiology. Using a proteomics approach, Wold and colleagues investigated how hypoxia inducible factor-1alpha served as a sensor for oxygen handling in the heart during cancer cachexia, a global hypoxic event. What strain and sex -dependent effects of tumor formation did Wold and co-authors observe in their model of cancer cachexia? Why was it significant that c-kit was elevated in the left ventricle of the tumor-bearing mice? Does lipid accumulation in the cachexia model bear resemblance to accelerated aging? Many questions, many answers. Listen now.
Raymond D. Devine, Sabahattin Bicer, Peter J. Reiser, Loren E. Wold Increased hypoxia-inducible factor-1α in striated muscle of tumor-bearing mice Am J Physiol Heart Circ Physiol, published June 1, 2017. DOI: 10.1152/ajpheart.00090.2016
August 13, 2017
What is the mechanism by which mental stress affects cardiac performance? Listen as Associate Editor Fabio Recchia (Temple University Lewis Katz School of Medicine, and Scuola Superiore Sant'Anna, Pisa, Italy) interviews lead author, and fellow Associate Editor, Ajay Shah (King’s College London) along with content expert Nazareno Paolocci (Johns Hopkins University) about the clinical translational work by Khan et al. Shah and co-authors explored for the first time the effects of mental stress elicited by the Stroop color-word test and coronary flow and diameter on patients undergoing elective diagnostic coronary catheterization. The key finding is that neuronal nitric oxide synthase (nNOS), in additional to endothelial nitric oxide synthase (eNOS), contributes to the local regulation of coronary flow in response to mental stress. The authors showed that the Stroop test stimulated nNOS without altering heart rate and blood pressure. Does this indicate specific stimulation of the perivascular nerves? Listen now to this intriguing podcast exploring cross-talk between the brain and heart.
Sitara Gulurkh Khan, Narbeh Melikian, Husain Shabeeh, Ana Rita Cabaco, Katherine Martin, Faisal Khan, Kevin O'Gallagher, Phil Chowienczyk, Ajay M. Shah The human coronary vasodilatory response to acute mental stress is mediated by neuronal nitric oxide synthase Am J Physiol Heart Circ Physiol, published June 23, 2017. DOI: 10.1152/ajpheart.00745.2016