Youngkeun Ahn

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Heart failure is associated with death of cardiomyocytes leading to loss of contractility. Previous studies using membrane-targeted Akt (myristolated-Akt), an enzyme involved in antiapoptotic signaling, showed inhibition of cell death and prevention of pathogenesis induced by cardiomyopathic stimuli. However, recent studies by our group have found(More)
Mesenchymal stem cells (MSCs) have been widely studied for their applications in stem cell-based regeneration. During myocardial infarction (MI), infiltrated macrophages have pivotal roles in inflammation, angiogenesis and cardiac remodeling. We hypothesized that MSCs may modulate the immunologic environment to accelerate regeneration. This study was(More)
The work demonstrated the development of thermally cross-linked superparamagnetic nanomaterial which possessed polyethylene glycol moiety and covalently linked branched polyethylenimine (BPEI), and exhibited highly efficient magnetofection even under serum conditioned media. The study showed its high anti-biofouling, cell viability and serum stability and(More)
OBJECTIVE The proliferation and remodeling of vascular smooth muscle cells (VSMCs) is an important pathological event in atherosclerosis and restenosis. Here we report that microRNA-132 (miR-132) blocks vascular smooth muscle cells (VSMC) proliferation by inhibiting the expression of LRRFIP1 [leucine-rich repeat (in Flightless 1) interacting protein-1]. (More)
OBJECTIVE Sulforaphane, a naturally occurring organosulfur compound in broccoli, has chemopreventive properties in cancer. However, the effects of sulforaphane in vascular diseases have not been examined. We therefore aimed to investigate the effects of sulforaphane on vascular smooth muscle cell (VSMC) proliferation and neointimal formation and the related(More)
Angiogenesis is the main therapeutic mechanism of cell therapy for cardiovascular diseases, but diabetes is reported to reduce the function and number of progenitor cells. Therefore, we studied the effect of streptozotocin-induced diabetes on the bone marrow-mesenchymal stem cell (MSC) function, and examined whether diabetes-impaired MSC could be rescued by(More)
OBJECTIVE The conventional method for the analysis of myocardial cell transplantation depends on postmortem histology. Here, we have sought to demonstrate the feasibility of a longitudinal monitoring of transplanted cell survival in living animals, accomplished with optical imaging techniques and pharmacological interventions. METHODS Human cord blood (50(More)
In this study, we present nanofiber-mediated gene delivery for myocardial infarction (MI). Branched polyethylenimine cross-linked via disulfide bonds (ssPEI) complexed with vascular endothelial growth factor (VEGF) were immobilized on electrospun polycaprolactone (PCL)/polyethylenimine (PEI) nanofibers for the local expression of VEGF angiogenic factor. We(More)
Restenosis is the formation of blockages occurring at the site of angioplasty or stent placement. In order to avoid such blockages, the suppression of smooth muscle cells near the implanted stent is required. The Akt1 protein is known to be responsible for cellular proliferation, and specific inhibition of Akt1 gene expression results in the retardation of(More)
High glucose-insulted bone marrow-derived mesenchymal stem cells (BMCs) showed impaired angiogenesis along with downregulation of stem cell factor (SCF). This study was designed to determine the involvement of microRNAs (miR), which are actively involved in the physiological function of stem cells. We observed that miR-34c was significantly induced by high(More)