Guidelines for Doppler Ultrasound and Resistance Vessel Function

How can researchers ensure that Doppler ultrasound measurements of human resistance vessel function are both accurate and repeatable? Listen as Editor in Chief Dr. Irving H. Zucker (University of Nebraska Medical Center) interviews the lead authors of this Guidelines in Cardiovascular Research article— Jacqueline K. Limberg (University of Missouri), Jaume Padilla (University of Missouri), Darren P. Casey (University of Iowa), Joel Trinity (University of Utah). The authors discuss the need for clear inclusion and exclusion criteria for human subjects, as well as the necessity of avoiding several key environmental stressors for a period of time prior to assessments. As a result of collaborating with experts around the globe, the authors developed a comprehensive figure and tables to outline considerations surrounding medication use and the potential impact of medication on vascular function, as well as other concerns for study participants such as caffeine intake, alcohol use, posture, and sleep. What is the best ambient room temperature to avoid confounding results related to skin blood flow when evaluating total limb blood flow to skeletal muscle? For the answer to this key question and more, listen now.

 

Jacqueline K. Limberg, Darren P. Casey, Joel D. Trinity, Wayne T. Nicholson, D. Walter Wray, Michael E. Tschakovsky, Daniel J. Green, Ylva Hellsten, Paul J. Fadel, Michael J. Joyner, Jaume Padilla Assessment of resistance vessel function in human skeletal muscle: guidelines for experimental design, Doppler ultrasound, and pharmacology  Am J Physiol Heart Circ Physiol, published January 31, 2020. DOI: doi.org/10.1152/ajpheart.00649.2019

Behind the Bench Episode 2

In this episode, Jonathan Kirk (Loyola University Chicago) and Lisandra de Castro Bras (East Carolina University) talk with Ninette Shenouda, an ambitious and savvy researcher at the University of Delaware. While finishing her PhD at McMaster University, Ninette co-authored two papers investigating the influence of sex hormones on flow-mediated dilation. While conducting her experiments, Ninette mastered the deceptively complex technique of measuring FMD and navigated some unpredictable situations with study participants. It was an APS Connect job posting that led Ninette to her current post-doc position, in which she has expanded her skill set by studying pulsatile load and connections between heart and brain function in kidney disease. Ninette speaks with refreshing honesty and wisdom about a pivotal moment early in her PhD when she wondered if she could trust her data, and the choice she faced to either stay discouraged or “find a way to get better.” Clearly Ninette chose the latter. This podcast will resonate with every trainee. We cover the importance of becoming affiliated with a professional society in your area of research, thinking two steps ahead of your current position, and perhaps the most valuable take-away: developing expertise which round out your skill portfolio to make you uniquely marketable. Oh, and #ScienceRomance is a thing. Listen now.

 

Ninette Shenouda, Stacey E. Priest, Vanessa I. Rizzuto, Maureen J. MacDonald Brachial artery endothelial function is stable across a menstrual and oral contraceptive pill cycle but lower in premenopausal women than in age-matched men Am J Physiol Heart Circ Physiol, published August 8, 2019. DOI: doi.org/10.1152/ajpheart.00102.2018

 

Stacey E. Priest, Ninette Shenouda, and Maureen J. MacDonald Effect of sex, menstrual cycle phase, and monophasic oral contraceptive pill use on local and central arterial stiffness in young adults Am J Physiol Heart Circ Physiol, published August 8, 2019. DOI: doi.org/10.1152/ ajpheart.00039.2018

Behind the Bench Episode One: Cam Squared

Welcome to our very first episode of Behind the Bench from AJP-Heart and Circ, where we try to get the story behind the story from the researchers themselves. In this episode we talk with Camilla Wenceslau, an Assistant Professor at University of Toledo, and Cameron McCarthy, a Postdoctoral to Faculty Fellow also at University of Toledo. Camilla and Cam co-authored a recent article in AJP-Heart and Circ. They’re both early career investigators, and husband and wife. We enlisted the help of Jonathan Kirk (Loyola University Chicago) and Lisandra de Castro Bras (East Carolina University) to interview this dynamic duo, with special cameo appearances by some familiar AJP-Heart and Circ personalities. How did science bring “Cam Squared” together? Let’s find out.

 

Cameron G. McCarthy, Camilla F. Wenceslau, Fabiano B. Calmasini, Nicole S. Klee, Michael W. Brands, Bina Joe, and R. Clinton Webb Reconstitution of autophagy ameliorates vascular function and arterial stiffening in spontaneously hypertensive rats Am J Physiol Heart Circ Physiol, published October 23, 2019. DOI: doi.org/10.1152/ajpheart.00227.2019

Cortical Bone Derived Stem-Cell Therapy Reduces Apoptosis

How do cortical bone derived stem cells reduce scar size and improve cardiac function following myocardial infarction? Guest Editor Lorrie Kirshenbaum (St. Boniface General Hospital Research Centre) interviews authors Steven Houser (Temple University) and Alexander Hobby (Temple University), along with Associate Editor Junichi Sadoshima (Rutgers New Jersey Medical School), about the innovative new study by Hobby et al showing CBSCs reduce apoptosis of both myocytes and non-myocytes in a large animal model of reperfusion injury. Hobby et al found that CBSCs increased the number of T cells and macrophages in the heart, which may mean that the cardioprotective effects of CBSCs could be mediated through T cells. What do our experts have to say about the overall state of stem cell therapy, how CBSCs differ from other conventional types of stem cells, and the potential clinical application of CBSCs for post-MI wound healing? Listen now.

 

Alexander R. H. Hobby, Thomas E. Sharp 3rd, Remus M. Berretta, Giulia Borghetti, Eric Feldsott, Sadia Mohsin, Steven R. Houser Cortical bone-derived stem cell therapy reduces apoptosis after myocardial infarction Am J Physiol Heart Circ Physiol, published October 7, 2019. DOI: doi.org/10.1152/ajpheart.00144.2019

Angiogenic Exosomes from Vascular Progenitor Cells

Where did the search to find exosome donor cells lead the authors of the new study by Johnson et al? Editor in Chief Irving H. Zucker (University of Nebraska Medical Center) interviews authors Dong Liu (Morehouse School of Medicine) and Takerra Johnson (National Institutes of Health/ National Eye Institute), along with content expert Jean-Pyo Lee (Tulane University), about this novel study which utilized induced vascular progenitor cells as exosome donor cells to promote angiogenesis. The authors determined that secretion is more important to endothelial cells than differentiation, because secretion includes growth factors, cytokines, and exosomes. Compared to rat aortic endothelial cells, induced vascular progenitor cells have a greater secretion of exosomes. Johnson et al found that iVPCs promoted angiogenesis in a rat hindlimb ischemia model. What did the authors uncover when they investigated the microRNA cargo carried by iVPC exosomes? Listen and learn more.

 

Takerra K. Johnson, Lina Zhao, Dihan Zhu, Yang Wang, Yan Xiao, Babayewa Oguljahan, Xueying Zhao, Ward G. Kirlin, Liya Yin, William M. Chilian, and Dong Liu Exosomes derived from induced vascular progenitor cells promote angiogenesis in vitro and in an in vivo rat hindlimb ischemia model Am J Physiol Heart Circ Physiol, published October 1, 2019. DOI: doi.org/10.1152/ajpheart.00247.2019

“Fit-for-Purpose” Approach to Antibody Validation

Why is it critical for researchers to take the time to validate their antibodies and protocols used in specific applications? Associate Editor Crystal Ripplinger (University of California Davis) interviews lead author Rebekah Gundry (University of Nebraska Medical Center) and Deputy Editor Merry Lindsey (University of Nebraska Medical Center) about this unique Perspective by Matthew Waas and Rebekah Gundry that proposes an approach for antibody validation for flow cytometry assessment of stem cell-derived cardiomyocytes used in cardiovascular physiology and translational research. We address the rigor and reproducibility hurdles researchers face when standardizing immunophenotyping protocols, as well as the challenges of including sufficient experimental details in manuscripts when faced with publisher-mandated manuscript word counts. Waas and Gundry call for moving away from the term “validation” and instead adopting “fit-for-purpose.” How does this fit with the concept of “trust but verify” and new NIH antibody authentication documents required for grant submissions? Listen now.

 

Matthew Waas and Rebekah L. Gundry A call to adopt a 'fit-for-purpose' approach to antibody validation for flow cytometry analyses of stem cell models and beyond Am J Physiol Heart Circ Physiol, published October 23, 2019. DOI: doi.org/10.1152/ajpheart.00347.2019

Spinal Cord Stimulation Blunts Dorsal Root Transduction of the Ischemic Ventricle

Can neuromodulation be used to change the sensory transduction of the ischemic ventricle? To answer this question, Editor-in-Chief Dr. Irving H. Zucker (University of Nebraska Medical Center) interviewed lead author Jeffrey Ardell ( University of California Los Angeles) and content expert Marc Kaufman (Pennsylvania State University) about the new work by Salavatian et al. Ardell and co-authors found that preemptive spinal cord stimulation can reduce the afferent signal coming from the ischemic ventricle. Was this a result of a change in substrate utilization in the heart or was this “silent ischemia”? Does this spinal cord stimulation work by Ardell and collaborators have the potential to translate to reducing pain for patients with angina? Don’t miss the extra “off the record” commentary at the end to find out.

 

Siamak Salavatian, Sarah M. Ardell, Mathew Hammer, David Gibbons, J. Andrew Armour, Jeffrey L. Ardell Thoracic spinal cord neuromodulation obtunds dorsal root ganglion afferent neuronal transduction of the ischemic ventricle Am J Physiol Heart Circ Physiol, published November 4, 2019. DOI: doi.org/10.1152/ajpheart.00257.2019

Guidelines for Evaluating Myocardial Cell Death

It’s well known that myocardial cell death leads to cardiac remodeling and heart failure. It is, however, less well known exactly which mechanisms lead to myocyte cell death in the heart. In our latest podcast, Associate Editor Junichi Sadoshima (Rutgers New Jersey Medical School) interviews lead authors Paras Mishra (University of Nebraska Medical Center), Joseph Hill (University of Texas Southwestern Medical Center), Peter Kang (Beth Israel Deaconess Medical Center), James Downey (University of South Alabama) and Takashi Matsui (University of Hawaii at Manoa) about their recent comprehensive Guidelines in Cardiovascular Research article on evaluating myocardial cell death. Listen as our experts—all of whom are global thought-leaders in their individual fields—delve into the 6 main mechanisms of cell death in the heart: apoptosis, ferroptosis, autophagic cell death, necroptosis, MPT-mediated necrosis, pyroptosis, autosis.

 

Paras K. Mishra, Adriana Adameová, Joseph A. Hill, Christopher P. Baines, Peter M. Kang, James Downey, Jagat Narula, Masafumi Takahashi, Antonio Abbate, Hande C. Piristine, Sumit Kar, Shi Su, Jason K. Higa, Nicholas K. Kawasaki, Takashi Matsui Guidelines for evaluating myocardial cell death Am J Physiol Heart Circ Physiol, published October 23, 2019. DOI: doi.org/10.1152/ajpheart.00259.2019

Experimental Design: Survey, Training & Practical Tools

Is it possible for preclinical researchers to improve the quality of their cardiac and metabolic animal studies by incorporating protocols and strategies aimed at reducing bias? Listen as Deputy Editor Merry L. Lindsey (University of Nebraska Medical Center) interviews lead author Julie R. McMullen (Baker Heart & Diabetes Institute) and content expert Lisandra de Castro Brás (East Carolina University) about the study by Weeks et al., the latest article in the AJP-Heart and Circulatory Physiology Cores of Reproducibility in Physiology series. McMullen and co-authors conducted a short survey of preclinical research colleagues about how animal studies were being performed, with a focus on blinding, randomization and allocation concealment. The survey was followed by skills training aimed at improving practices, such as computer-generated methods for randomization and de-identifying drugs and interventions. Why take on this project? By providing basic scientists with tools to correctly randomize animals, and rationale to pre-specify inclusion and exclusion criteria, pre-specify endpoints, and appropriately address negative data, McMullen and collaborators hope to equip investigators with tools and knowledge to remove unconscious bias. This includes the encouragement of team science among smaller labs to allow for improvements in experimental design such as allocation concealment, which requires more personnel. Listen now to learn more.

 

Kate L. Weeks, Darren C. Henstridge, Agus Salim, Jonathan E. Shaw, Thomas H. Marwick, Julie R. McMullen CORP: Practical Tools for Improving Experimental Design and Reporting of Laboratory Studies of Cardiovascular Physiology and Metabolism Am J Physiol Heart Circ Physiol, published July 26, 2019. DOI: doi.org/10.1152/ajpheart.00327.2019

CD161a+ Immune Cells in Cholinergic Hypertension

How do the immune system, nervous system, and renal system interact in the pathogenesis of hypertension? In this podcast Editor in Chief Irving H. Zucker (University of Nebraska Medical Center) interviews lead author Sailesh Harwani (University of Iowa) and content expert Liang Xiao (Vanderbilt University) about the new study by Raikwar et al, which used a spontaneously hypertensive rat model in a pre-hypertensive state to determine the causality of the multi-system components. The study design involved two interventions--complete bi-lateral renal denervation, and ablation of CD161a+ immune cells. The authors found that administering nicotine in the renal denervation group prevented cholinergic hypertension. Blood pressure elevation and renal inflammation were prevented in both the renal denervation and CD161a+ ablation intervention groups by administering nicotine. Does the location of CD161 immune cells at the vertex between the kidneys and immune systems play a pivotal role in how these cells are influenced by the adrenergic and cholinergic nervous systems? Listen and find out.

 

Nandita Raikwar, Cameron Braverman, Peter M. Snyder, Robert A. Fenton, David K. Meyerholz, Francois M. Abboud, and Sailesh C. Harwani Renal denervation and CD161a immune ablation prevent cholinergic hypertension and renal sodium retention Am J Physiol Heart Circ Physiol, published August 20, 2019. DOI: doi.org/10.1152/ajpheart.00234.2019