September 27, 2021
Is the loss of endothelin-B receptor mediated vasodilation in women after menopause due to aging or the decline in estradiol that occurs with menopause? Associate Editor Dr. Jason Carter (Montana State University) interviews senior author Megan Wenner (University of Delaware) and content expert Lacy Alexander (Pennsylvania State University) about the work by Wenner and co-authors to isolate and study specific effects of estradiol on the regulation of the ETB receptor. Shoemaker et al. enrolled young women in their study and utilized an endogenous hormone suppression with estradiol add-back experimental design to eliminate changes related to aging and other sex hormones. Wenner and collaborators then measured microvascular endothelial function using laser Doppler flowmetry while perfusing an antagonist for the ETB receptor via intradermal microdialysis fiber, a technique pioneered by Lacy Alexander. The authors found that when estradiol is present, the ETB receptor mediates vasodilation. However, when estradiol is absent or suppressed, ETB-mediated dilation is lost. Bottom line: changes in estradiol regulate the function of this ETB receptor. What is the clinical relevance of this work for women’s health, in particular related to endometriosis, premature ovarian failure, and other pathophysiological conditions related to dysregulated sex hormones? Listen to learn more about this fascinating study and its implications on women’s overall cardiovascular health.
Leena N. Shoemaker, Katherine M. Haigh, Andrew V. Kuczmarski, Shane J. McGinty, Laura M. Welti, Joshua C. Hobson, David G. Edwards, Ronald F. Feinberg, and Megan M. Wenner ETB receptor-mediated vasodilation is regulated by estradiol in young women
Am J Physiol Heart Circ Physiol, published September 3, 2021.
September 15, 2021
Is cardiac remodeling associated with an increase in left ventricular dyssynchrony and post-systolic shortening in young bodybuilders using anabolic-androgenic steroids? Guest Host Brady Holmer (University of Florida) interviews lead author Stéphane Nottin (Avignon University) and content expert Austin Robinson (Auburn University) to get the answers. The groundbreaking work by Grandperrin et al. is the first study to investigate the presence of LV dyssynchrony in strength-trained male athletes using anabolic-androgenic steroids. Black-market steroids are illegal in most sports, yet easily available to athletes on the internet. It is well documented in the literature that use of anabolic-androgenic steroids by strength-trained athletes leads to deleterious cardiac hypertrophy with non-reversible myocardial dysfunction. The authors studied three groups: 1) young male bodybuilders who self-reported substantial use of anabolic-androgenic steroids; 2) young male bodybuilders who self-reported to have never used anabolic-androgenic steroids; 3) young untrained control subjects. Nottin and co-authors evaluated regional strains via resting echocardiography, and found that the group of young male bodybuilders who reported substantial steroid use showed increased LV mechanical dispersion, which correlated with increased LV mass and LV post-systolic shortening. Our experts discuss long term cardiovascular risks to anabolic-androgenic steroid users, as well as future directions and unique techniques needed to study female bodybuilders using anabolic-androgenic steroids. This episode is a must-listen for athletes, coaches, and exercise physiologists alike. Listen now.
Antoine Grandperrin, Iris Schuster, Thomas Rupp, Omar Izem, Philippe Obert, and Stéphane Nottin Left ventricular dyssynchrony and post-systolic shortening in young bodybuilders using anabolic-androgenic steroids Am J Physiol Heart Circ Physiol, published August 25, 2021. DOI: 10.1152/ajpheart.00136.2021
September 7, 2021
Allow us to introduce you to Tommy Martin, a trainee in The Kirk Lab at Loyola University Chicago, who is scheduled to defend his PhD thesis in October 2021. Tommy is first author on a recently published AJP-Heart and Circ article, which is co-authored by Jonathan Kirk, an Associate Editor for AJP-Heart and Circ, and a founding member of our Behind the Bench podcast crew. Tommy has a story that will resonate with trainees and early career researchers: he was vacillating between going to medical school and getting a PhD. His interview with the very personable and enthusiastic Jonathan Kirk was the deciding factor to take the fork in the road that led to graduate school for a PhD in cardiovascular research. Our intrepid Behind the Bench co-hosts Lisandra de Castro Brás (East Carolina University) and Charlotte Usselman (McGill University) interview Tommy about life in the lab as a would-be medical student, learning how to use a pipette for the first time, his best advice to trainees for how to nail the post-doc interview process, and the drive and commitment necessary to pursue success in science. We also get the inside scoop about all things Jonathan Kirk (that beard!), and along the way we manage to discuss BAG3 protein expression in sarcomeric proteins in heart failure. Tommy Martin is engaging, sharp and clearly a rising star in cardiovascular research. Listen now, and don’t miss the bonus outtake after the credits.
Thomas G. Martin, Sara Tawfik, Christine S. Moravec, Toni R. Pak, Jonathan A. Kirk BAG3 expression and sarcomere localization in the human heart are linked to HSF-1 and are differentially affected by sex and disease Am J Physiol Heart Circ Physiol, published May 26, 2021.