In vitro studies of early cardiac remodeling: impact on contraction and calcium handling

Mesenchymal stem cell-derived exosomes in cardiovascular and cerebrovascular diseases: From mechanisms to therapy

Cardiovascular and cerebrovascular diseases (CVDs) remain an intractable problem and have high morbidity and mortality worldwide, as well as substantial health and economic burdens, representing an urgent clinical need. In recent years, the focus of research has shifted from the use of mesenchymal stem cells (MSCs) for transplantation to the use of their secretory exosomes (MSC-exosomes) for the treatment of numerous CVDs, including atherosclerosis, myocardial infarction (MI), heart failure (HF), ischemia/reperfusion (I/R), aneurysm, and stroke. MSCs are pluripotent stem cells with multiple differentiation pathways that exert pleiotropic effects by producing soluble factors, the most effective components of which are exosomes. MSC-exosomes are considered to be an excellent and promising cell-free therapy for CVDs due to their higher circulating stability, improved biocompatibility, reduced toxicity, and immunogenicity. In addition, exosomes play critical roles in repairing CVDs by inhibiting apoptosis, regulating inflammation, ameliorating cardiac remodeling, and promoting angiogenesis. Herein, we describe knowledge about the biological characteristics of MSC-exosomes, investigate the mechanism by which MSC-exosomes mediate therapeutic repair, and summarize recent advances in the efficacy of MSC-exosomes in CVDs, with a view toward future clinical applications.

Exosomes in cardiovascular diseases: a blessing or a sin for the mankind

Cardiovascular diseases (CVDs) comprises disorders of blood vessels and heart. Multiple cells in the heart suggests that hetero-cellular communication, which is an important aspect in heart functioning and there is a need to elucidate the way in which this inter-cellular communication occurs. Now a days, exosomal research has gained much attention. Exosomes, nano-shuttles, are EVs with diameters ranging from 40 to 160 nm (average 100 nm), secreted by body cells. These vesicles act as cell-to-cell communicators and are carriers of important biomolecules such as RNAs, miRNAs, Proteins and lipids. Exosomes can change the gene expression of the recipient cells, thereby, changes the cellular characteristics. Exosomes have known to play an essential role in protection as well as progression of various cardiovascular diseases. In the present review, role of exosomes in various CVDs have been discussed.

Exosomes in mesenchymal stem cells, a new therapeutic strategy for cardiovascular diseases?

Cardiovascular diseases (CVDs) are still a major cause of people deaths worldwide, and mesenchymal stem cells (MSCs) transplantation holds great promise due to its capacity to differentiate into cardiovascular cells and secrete protective cytokines, which presents an important mechanism of MSCs therapy for CVDs. Although the capability of MSCs to differentiate into cardiomyocytes (CMCs), endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) has been well recognized in massive previous experiments both in vitro and in vivo, low survival rate of transplanted MSCs in recipient hearts suggests that therapeutic effects of MSCs transplantation might be also correlated with other underlying mechanisms. Notably, recent studies uncovered that MSCs were able to secret cholesterol-rich, phospholipid exosomes which were enriched with microRNAs (miRNAs). The released exosomes from MSCs acted on hearts and vessels, and then exerted anti-apoptosis, cardiac regeneration, anti-cardiac remodeling, anti-inflammatory effects, neovascularization and anti-vascular remodeling, which are considered as novel molecular mechanisms of therapeutic potential of MSCs transplantation. Here we summarized recent advances about the role of exosomes in MSCs therapy for CVDs, and discussed exosomes as a novel approach in the treatment of CVDs in the future.

The S100A6 calcium-binding protein regulates endothelial cell-cycle progression and senescence

Endothelial cells regulate many aspects of vascular physiology, including vasculogenesis and angiogenesis. The S100 family of calcium-binding proteins regulates many aspects of cell function but their roles in vascular physiology are less well understood. Herein, we investigated the expression and function of S100-related family members in endothelial cells. Analysis of total endothelial mRNAs using a human gene chip array revealed significant gene expression of the S100 calcium-binding protein family members S100A6, S100A10, S100A11 and S100A13. We then examined the expression and functional properties of the major S100 family member, S100A6, in vascular endothelial cells. Comparison of primary and transformed human cells revealed significant differences in S100A6 protein levels in these cells. In primary human endothelial cells, S100A6 was present in both the nucleus and the cytoplasm. To assess the function of endothelial S100A6, we depleted protein levels using RNA interference and this caused increased cell-cycle arrest in the G2/M phase under different conditions. S100A6 depletion caused a decrease in both cyclin-dependent kinase 1 (CDK1) and phospho-CDK1 levels, which are essential for eukaryote cell-cycle progression. S100A6 depletion also decreased expression of CDK1, cyclin A1 (CCNA1) and cyclin B (CCNB1) genes with effects on cell-cycle progression. Depletion of endothelial S100A6 levels also elevated β-galactosidase expression, which is an important hallmark of cellular senescence and exit from the mammalian cell cycle. We thus propose that S100A6 has an important role in regulating endothelial commitment to, and progression through, the cell cycle.