Inhibiting Extracellular Vesicle Release from Human Cardiosphere Derived Cells with Lentiviral Knockdown of nSMase2 Differentially Effects Proliferation and Apoptosis in Cardiomyocytes, Fibroblasts and Endothelial Cells In Vitro.
Numerous studies have shown a beneficial effect of cardiosphere-derived cell (CDC) therapy on regeneration of injured myocardium. Paracrine signaling by CDC secreted exosomes may contribute to improved cardiac function. However, it has not yet been demonstrated by a genetic approach that exosome release contributes to the therapeutic effect of transplanted CDCs. By employing a lentiviral knockdown (KD) strategy against neutral spingomyelinase 2 (nSMase2), a crucial gene in exosome secretion, we have defined the role of physiologically secreted human CDC-derived exosomes on cardiac fibroblast, endothelial cell and primary cardiomyocyte proliferation, cell death, migration and angiogenesis using a series of in vitro coculture assays. We found that secretion of hCDC-derived exosomes was effectively inhibited by nSMase2 lentiviral KD and shRNAi expression was stable and constitutive. hCDC exosome release contributed to the angiogenic and pro-migratory effects of hCDCs on HUVECs, decreased proliferation of fibroblasts, and decreased apoptosis of cardiomyocytes. These in vitro reactions support a role for exosome secretion as a paracrine mechanism of stem cell-mediated cardiac repair in vivo. Importantly, we have established a novel tool to test constitutive inhibition of exosome secretion in stem cell populations in animal models of cardiac disease.
Department of Medicine, Division of Cardiology, Jacobs School of Medicine and Biomedical Sciences, Buffalo, N.Y, 14203, United States of America.
Jennifer K
http://orcid.org/0000-0002-6221-8625
JK
Lang
Department of Medicine, Division of Cardiology, Jacobs School of Medicine and Biomedical Sciences, Buffalo, N.Y, 14203, United States of America.
Rebeccah F
RF
Young
Department of Cardiothoracic Surgery, Kaleida Health, Buffalo, N.Y, 14203, United States of America.
Hashmat
H
Ashraf
Department of Medicine, Division of Cardiology, Jacobs School of Medicine and Biomedical Sciences, Buffalo, N.Y, 14203, United States of America.|VA WNY Healthcare System, Buffalo, N.Y., 14215, United States of America.
John M
JM
Canty
D017209:Apoptosis; D049109:Cell Proliferation; D002478:Cells, Cultured; D018920:Coculture Techniques; D042783:Endothelial Cells / Q000166:cytology*; D000067128:Extracellular Vesicles / Q000378:metabolism*; D005347:Fibroblasts / Q000166:cytology*; D055785:Gene Knockdown Techniques / Q000379:methods*; D006801:Humans; D066298:In Vitro Techniques; D016086:Lentivirus / Q000235:genetics; D032383:Myocytes, Cardiac / Q000166:cytology*; D019899:Paracrine Communication; D013108:Sphingomyelin Phosphodiesterase / Q000235:genetics*
C491484:SMPD3 protein, human; D013108:Sphingomyelin Phosphodiesterase