What’s better than discussing one paper on the effects of cortical bone stem cells and their impact on myocardial infarction? Discussing two papers! Associate Editor Dr. Jonathan Kirk (Loyola University Chicago Stritch School of Medicine) interviews lead authors Dr. Timothy McKinsey (University of Colorado Anschutz Medical Campus) and Dr. Steven R. Houser (Lewis Katz School of Medicine at Temple University) along with expert Dr. Helen Collins (University of Louisville School of Medicine). The latest collaborations from the Houser lab and the McKinsey lab could pave the way for significant advancements in understanding how exosomes derived from cortical bone stem cells (CBSCs) may have the ability to reduce injury from acute myocardial infarction (MI). In the study by Schena et al., Houser and co-authors used an ischemia/reperfusion model and found that, if given soon enough after injury, CBSC-derived exosomes had an acute protective effect on infarct size. The authors then found that secreted factors from CBSCs and their exosomes modified fibroblasts in ways that likely alter MI scar formation. In the study by Hobby et al., McKinsey and co-authors found that CBSCs influence macrophage polarity in vitro toward an anti-inflammatory protective phenotype. Those macrophages, which had been treated with CBSC-derived factors, influenced fibroblasts to become less fibrotic yet more proliferative. Enter small nucleolar RNA (snoRNA) into this story as important regulators of protein translation. Downregulating snoRNAs in turn downregulated protein translation and blocked fibroblast activation. Our experts discuss the advantages and challenges of conducting large animal studies, the opportunities for discovery with snoRNAs, and the exciting future ahead for translational heart failure research. Listen and learn more.

Giana J. Schena, Emma K. Murray, Alycia N. Hildebrand, Alaina L. Headrick, Yijun Yang, Keith A. Koch, Hajime Kubo, Deborah Eaton, Jaslyn Johnson, Remus Berretta, Sadia Mohsin, Raj Kishore, Timothy A. McKinsey, John W. Elrod, and Steven R. Houser Cortical bone stem cell-derived exosomes’ therapeutic effect on myocardial ischemia-reperfusion and cardiac remodeling Am J Physiol Heart Circ Physiol, published November 8, 2021. DOI: 10.1152/ajpheart.00197.2021

Alexander R. H. Hobby, Remus M. Berretta, Deborah M. Eaton, Hajime Kubo, Eric Feldsott, Yijun Yang, Alaina L. Headrick, Keith A. Koch, Marcello Rubino, Justin Kurian, Mohsin Khan, Yinfei Tan, Sadia Mohsin, Stefania Gallucci, Timothy A. McKinsey, and Steven R. Houser Cortical bone stem cells modify cardiac inflammation after myocardial infarction by inducing a novel macrophage phenotype Am J Physiol Heart Circ Physiol, published September 23, 2021. DOI: 10.1152/ajpheart.00304.2021