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Introduction:Although transplantation of mesenchymal stem cell (MSC) is a promising therapeutic option for myocardial infarction, its? therapeutic effects are not satisfactory especially for severely damaged heart, which propose some modifications in cell therapy. One possibility may be how to enhance cytokine expression especially endothelial nitric oxide synthase (eNOS) based on cellular tissue transplantation.Hypothesis:In this study, we hypothesized that fibrin scaffold stimulates the NOx production in ADSC and the NOx may depend on the cardiac functional recovery after myocardial infarction.Methods and Results:In-vitro, ADSC embedded in fibrin-gel produced more eNOS and NO than 2-dimensionally cultured-ADSC did significantly (about 2.5 and 2 folds respectively).N(G)-nitro-L-arginine methyl ester (L-NAME), which is a non-selective NOS inhibitor, is added to ADSC and NOx production and cell viability were monitored. The cell viability was not changed and NOx production was almost completely blocked by L-NAME.In-vivo, transplantation of ADSC with or without L-NAME (group N and A respectively) on the heart surfaceor sham operation (group C) was performed in rats that were subjected to LAD ligation 2 weeks prior to the treatment (n=7 each).The number of transplant cell was 1x10^6/body. The cardiac function assessed with echocardiography was significantly better in group A than group N and C (EF:A, N and C group; 55%, 50% and 40%, p<0.05).Histological analysis revealed the capillary density in peri infarct area was increased and the cadiomyocyte dimeter was significantly decreased in A group compared with the other groups.Conclusion:Cellular tissue transplantation using fibrin scaffold and ADSCs enhanced NO production from ADSC in vitro and vivo examination, suggesting possibility in better clinical outcomes of cellular therapy for ischemic cardiomyopathy.

Introduction:Although transplantation of Mesenchymal stem cell (MSC) shows efficacy in the treatment of ischemic cardiomyopathy, its? therapeutic mechanisms have not been fully elucidated.It has been already reported that mitochondria transfer (MT) from MSC to recipient cells have impact on resistance to cell injury and tissue regeneration.Hypothesis:We examined the MT observing the co-culture of adipose-derived MSC (ADSC) and cardiomyocytes (CM) for 24 hours under hypoxia with analyze of the mitochondrial function and motion of CMand checked functional recovery in rat infarction model.Methods and Results:In-vitro, the co-culture of rat CM and human ADSC was observed with time-lapse photography and demonstrated mitochondrial transfer under the hypoxic condition. In addition, fixed sample showed granular shape transferred MT in CM clearly.To evaluate the energy metabolism, the oxygen consumption rate (OCR), one of the indicators of mitochondrial respiration and glycolysis, was reinforced by co-culture with ADSC conspicuously (CM:54.3, ADSC:47.1, CM+ADSC:129.7 pmol/min).On the other hands addition of alpha-glycyrrhetinic acid (?GA), a blocker of the cell-cell junction formation through connexin 43, canceled these phenomena.Next the culture supernatant of ADSC was added to the freshly isolated CM and the motion of these cell were analyzed withmotion analysis system. The contractile force and heart rate were not affected by addition of culture supernatant, indicating that cytokines dose not directly effect on CM and cell-cell contact was required for MT.In-vivo, transplantation of ADSC (group A) with/without ?GA to the heart surfaceor sham operation (group C) was performed in rats infarction model(n=7 each).The number of transplant cell was 1x10^6/body. Three days after transplantation, transferred mitochondria were observed in recipient CM histologically. The cardiac function assessed with echocardiography was significantly better in group A (Ejection fraction; A vs. C vs. A+?GA: 59.2 vs. 46.4 vs. 46.2%).Conclusion:Mitochondrial transfer from ADSC to CM was observed in-vitro and in-vivo ischemic/hypoxic condition,suggesting that mitochondrial transfer has some relations to functional recovery in the failed heart.

Introduction:Refractory dilated cardiomyopathy has been reported to have pathophysiologies such as abnormalities in cytoskeletal protein, mitochondrial ATP transporter, microvasculature, and fibrosis, which may be main therapeutic target. The Mesenchymal stem cells (MSCs) have been already reported to have a potential to ameliorate the distressed mitochondria, structural protein, and anti-fibrotic effects by cytokine paracrine effect.Hypothesis:In this study we hypothesized that MSC transplantation may recover the cardiac function through regulation of mitochondrial function and cytoskeletal protein.Methods and Results:The adipose-derived MSC (ADSC) were implanted onto the cardiac surface of the delta sarcoglycan(SG)-deficient hamster 18 weeks after birth (A group, n=10)and sham operation was performed(C group, n=10).In the A group, left ventricular ejection fraction and end-systolic diameter were maintained during 4 weeks after transplantation (A vs. C group; EF 42.8 vs. 25.3%, p<0.05). The ATP concentration in the cardiomyocytes was significantly increased in A group (A vs. C group; 1.89 vs. 1.20 mol/mg weight tissue, p<0.05).In addition, expression of ANT-1, an ATP counter transporter located at mitochondrial inner membrane, significantly upregulated in the A group(A vs. C group; 65.02 vs. 21.49 %ANT-1/COX4 (vs. Normal), p<0.05).Histologically there were no significant differences in the expression of extra-cellular matrix and myocardial cytoskeletal proteins such as collagen, SG and ?-dystroglycan between groups. However, significant improvement of myosin and Smad-4 gene expression, the cardiomyocyte hypertrophy and capillary density were detected in the A group.In vitro, ELISA analysis revealed that the ADSC secreted cytokine such as HGF, VEGF and activin. From the above results, activin may act on the TGF-beta receptor on cardiomyocytes and Smad-4 related intracellular cascade may involve in the up-regulation of myosin.Conclusions:ADSC, which can deliver cytokines to distressed cardiomyocytes, may improve cardiac function in the DCM-like hamster with amelioration of ATP concentration, mitochondrial transporter and myosin expression, proposing possibilities in clinical application of ADSC therapy for DCM.