Role of adenosine A2B receptor signaling in contribution of cardiac mesenchymal stem-like cells to myocardial scar formation

Purinergic Signalling

Alissa Weaver²  Igor Feoktistov¹  Richard J. Gumina²  Italo Biaggioni²  Qinkun Zhang²  Sergey Ryzhov²  Bong Hwan Sung² 

[1] Vanderbilt University$$;Vanderbilt University Medical School$$

关键词: Alpha-smooth muscle actin;   

DOI  :  10.1007/s11302-014-9410-y

学科分类：分子生物学，细胞生物学和基因

来源: Springer

【 摘 要 】

Adenosine levels increase in ischemic hearts and contribute to the modulation of that pathological environment. We previously showed that A_2B adenosine receptors on mouse cardiac Sca1⁺CD31⁻ mesenchymal stromal cells upregulate secretion of paracrine factors that may contribute to the improvement in cardiac recovery seen when these cells are transplanted in infarcted hearts. In this study, we tested the hypothesis that A_2B receptor signaling regulates the transition of Sca1⁺CD31⁻ cells, which occurs after myocardial injury, into a myofibroblast phenotype that promotes myocardial repair and remodeling. In vitro, TGFβ1 induced the expression of the myofibroblast marker α-smooth muscle actin (αSMA) and increased collagen I generation in Sca1⁺CD31⁻ cells. Stimulation of A_2B receptors attenuated TGFβ1-induced collagen I secretion but had no effect on αSMA expression. In vivo, myocardial infarction resulted in a rapid increase in the numbers of αSMA-positive cardiac stromal cells by day 5 followed by a gradual decline. Genetic deletion of A_2B receptors had no effect on the initial accumulation of αSMA-expressing stromal cells but hastened their subsequent decline; the numbers of αSMA-positive cells including Sca1⁺CD31⁻ cells remained significantly higher in wild type compared with A_2B knockout hearts. Thus, our study revealed a significant contribution of cardiac Sca1⁺CD31⁻ cells to the accumulation of αSMA-expressing cells after infarction and implicated A_2B receptor signaling in regulation of myocardial repair and remodeling by delaying deactivation of these cells. It is plausible that this phenomenon may contribute to the beneficial effects of transplantation of these cells to the injured heart.

【 授权许可】

Unknown