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Asahara, T.

Publications and source records attributed to Asahara, T..

2 recordsLinked to original sources

Dipeptidyl dipeptidase-4 inhibitor, MK-0626, promotes bone marrow-derived endothelial progenitor cell bioactivities for vascular regeneration in diet-induced obese mice

Metabolic syndrome (MS), overlapping type 2 diabetes, hyperlipidemia, and/or hypertension, based on high-fat diet, poses risk for cardiovascular disease. A critical feature associated with such risk is the functional impairment of endothelial progenitor cells (EPCs). Dipeptidyl dipeptidase-4 inhibitors are known not only to inhibit degradation of incretins to control blood glucose levels, but also to improve EPC bioactivity and induce anti-inflammatory effects in tissues. In the present study, we investigated the effects of such an inhibitor, MK-06266, in ischemia model of MS using diet-induced obese (DIO) mice. EPC bioactivity was examined in MK-0626-administered DIO mice and non-treated control group, using an EPC colony-forming assay and bone marrow cKit+ Sca-1+ lineage-cells, and peripheral blood-mononuclear cells. Our results showed that, in vitro, the effect of MK-0626 treatment on EPC bioactivities and differentiation was superior in comparison with non-treatment. Further, in vivo hindlimb ischemia model experiment indicated that microvascular density and pericyte-recruited arteriole number were increased in MK-0626-administered group, but not control group. Lineage profiling of isolated cells from ischemic tissues disclosed that MK-0626 administration has an inhibitory effect on unproductive inflammation. This occurred via a decrease in the influx of total blood cells and pro-inflammatory cells such as neutrophils, total macrophages, M1, total T-cells, cytotoxic T-cells, and B-cells, with a concomitant increase in number of regeneration-associated cells, such as M2/M ratio and Treg/T-helper. Laser Doppler analysis revealed that at day 14 after ischemic injury, blood perfusion in hindlimb was grater in DIO mice treated with MK-0626, but not in control. In conclusion, the dipeptidyl dipeptidase-4 inhibitor has a positive effect on EPC differentiation in MS model of DIO mice. Following ischemic injury, DPP-4 i sharply reduces recruitment of pro-inflammatory cells into ischemic tissue, and triggers regeneration and reparation process. Thus, DPP-4 i is a promising therapeutic agent for MS treatment.

cell biology

Regeneration-Associated Cells Improve Recovery from Myocardial Infarction through Enhanced Vasculogenesis, Anti-inflammation, and Cardiomyogenesis

BackgroundConsidering the impaired function of regenerative cells in patients with comorbidities and associated risk factors, cell therapy to enhance the regenerative microenvironment was designed using regeneration-associated cells (RACs), including endothelial progenitor cells (EPCs) and anti-inflammatory cells.\n\nMethodsRACs were prepared by quality and quantity control culture of blood mononuclear cells (QQMNCs). The peripheral blood mononuclear cells (PBMNCs) were isolated from Lewis rats and conditioned for 5 days using a medium containing stem cell factors, thrombopoietin, Flt-3 ligand, vascular endothelial growth factor, and interleukin-6 to generate QQMNCs.\n\nResultsIn vitro EPC colony forming assays demonstrated a 5.3-fold increase in the definitive colony-forming EPCs and vasculogenic EPCs, in comparison to naive PBMNCs. Flow cytometry analysis revealed that QQMNCs were enriched with RACs, such as EPCs (28.9-fold, P<0.0019) and M2 macrophages (160.3-fold, P<0.0002). Cell transcriptome analysis revealed that angiogenesis (angpt1, angpt2, and vegfb), stem/progenitor (c-kit and sca-1) and anti-inflammation related (arg-1, erg-2, tgfb, and foxp3) genes were highly expressed in QQMNCs. For in vivo cell transplantation experiments, 1x105 cells were administered via the tail vein into syngeneic rat models of myocardial infarction (MI). Echocardiographic data showed that QQMNCs-transplanted group (QQ-Tx) preserved cardiac function and fraction shortening (45.5{+/-}4.6%) at 28-days post-MI in comparison with PBMNCs-transplanted (PB-Tx) (30.9{+/-}6.4%, P<0.0001) and Control (32.2{+/-}7.7%, P<0.0008) groups. Histological analysis revealed that QQ-Tx showed enhanced angiogenesis and reduced interstitial left ventricular fibrosis, along with a decrease in neutrophils and an increase in M2 macrophages in the acute phase of MI. Cell tracing studies revealed that intravenously administered QQMNCs preferentially homed to ischemic tissues via blood circulation, while PBMNCs did not. QQ-Tx showed markedly upregulated early cardiac transcriptional cofactors (Nkx2-5, 29.8-fold, and Gata-4, 5.2- fold) as well as c-kit (4.5-fold) while these markers were downregulated in PB-Tx. In QQ-Tx animals, de novo blood vessels formed a \"Biological Bypass\" as observed macroscopically and microscopically, while PB-Tx and Control-Tx groups never developed epicardial blood vessels but showed severe fibrotic adhesion to the surrounding tissues.\n\nConclusionQQMNCs, as RACs derived from rat PBMNCs, conferred potent angiogenic and anti-inflammatory properties to the regenerative microenvironment, enhancing myocardiogenesis and functional recovery of rat MI hearts.

systems biology