Repetitive spikes of glucose and lipid induce senescence-like phenotypes of bone marrow stem cells through H3K27me3 demethylase-mediated epigenetic regulation.

Bone marrow-derived endothelial progenitor cells (EPCs) contribute to endothelial repair and angiogenesis. Reduced number of circulating EPCs is associated with future cardiovascular events. We tested whether dysregulated glucose and/or triglyceride (TG) metabolism has an impact on EPC homeostasis. The analysis of metabolic factors associated with circulating EPC number in humans revealed that postprandial hyperglycemia is negatively correlated with circulating EPC number, and this correlation appears to be further enhanced in the presence of postprandial hypertriglyceridemia (hTG). We therefore examined the effect of glucose/TG spikes on bone marrow lineage-sca-1+ c-kit+ (LSK) cells in mice, because primitive EPCs reside in bone marrow LSK fraction. Repetitive glucose + lipid (GL) spikes, but not glucose (G) or lipid (L) spikes alone, induced senescence-like phenotypes of LSK cells, and this phenomenon was reversible after cessation of GL spikes. G spikes and GL spikes differentially affected transcriptional program of LSK cell metabolism and differentiation. GL spikes upregulated a histone H3K27 demethylase JMJD3, and inhibition of JMJD3 eliminated GL spikes-induced LSK cell senescence-like phenotypes. These observations suggest that postprandial glucose/TG dysmetabolism modulate transcriptional regulation in LSK cells through H3K27 demethylase-mediated epigenetic regulation, leading to senescence-like phenotypes of LSK cells, reduced number of circulating EPCs, and development of atherosclerotic cardiovascular disease.NEW & NOTEWORTHY Combination of hyperglycemia and hypertriglyceridemia is associated with increased risk of atherosclerotic cardiovascular disease. We found that 1) hypertriglyceridemia may enhance the negative impact of hyperglycemia on circulating EPC number in humans and 2) metabolic stress induced by glucose + triglyceride spikes in mice results in senescence-like phenotypes of bone marrow stem/progenitor cells via H3K27me3 demethylase-mediated epigenetic regulation. These findings have important implications for understanding the pathogenesis of atherosclerotic cardiovascular disease in patients with T2DM.

Influence of different physiological hemodynamics on fractional flow reserve values in the left coronary artery and right coronary artery.

BACKGROUND: Although the left coronary artery (LCA) has a flow profile in that most blood flow occurs during diastole rather than systole, the right coronary artery (RCA) has a flow pattern that is less diastolic dominant. This study assessed whether coronary pressure waveforms distal to stenoses with the same fractional flow reserve (FFR) was the same between the LCA and RCA. METHODS: A total of 347 vessels from 318 patients who underwent FFR measurements were included. Conventional FFR was calculated as the ratio of the mean coronary distal pressure (Pd) to the mean aortic pressure (Pa) at maximal hyperemia. The pressure drop ratios in systole (PDRsystole) and diastole (PDRdiastole) were calculated as the sum of (Pa minus Pd) divided by the sum of Pa at the intracoronary diastolic and systolic pressure phases, respectively. RESULTS: Analysis of covariance of the regression line of correlation between conventional FFR and PDRsystole revealed that the slope was significantly greater in the RCA than in the left anterior descending artery (LAD) and left circumflex artery (LCX) (-0.765, -0.578, and -0.589, p < 0.001). On the other hand, the regression line of correlation between conventional FFR and PDRdiastole found that the slope was significantly greater in the LAD and LCX than in the RCA (-1.349, -1.318, and -1.223, p < 0.001). CONCLUSIONS: The pressure waveform distal to the stenosis differs between the LCA and RCA. In the LCA, the decrease in diastolic pressure mainly contributed to the drop in FFR, whereas in the RCA, it was the decrease in systolic pressure.

Heparin Induces the Mobilization of Heart-Derived Multipotent Mesoangioblasts During Cardiac Surgery With Cardiopulmonary Bypass or Cardiac Catheterization.

BACKGROUND: We previously identified circulating mesoangioblasts (cMABs), a subset of mesenchymal stem cells that express cardiac mesodermal markers, in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). We also found that hepatocyte growth factor (HGF) is upregulated during cardiac surgery with CPB in humans, and induces MAB-like cell mobilization in rodents. These results strongly suggest that heparin induced MAB mobilization via HGF upregulation. Here, we tested this hypothesis in patients undergoing cardiac surgery or cardiac catheterization. We also examined whether human cMABs are derived from the heart.Methods and Results:Plasma HGF levels were determined by ELISA. Mononuclear cells isolated from blood samples were cultured on fibronectin-coated dishes, and outgrowing cMAB colonies were counted. We first confirmed that HGF upregulation and cMAB mobilization were observed before the start of CPB, excluding the possibility that CPB is the primary inducer of cMAB mobilization. We then examined patients undergoing cardiac catheterization and found that heparin significantly increased plasma HGF levels and the number of cMAB colonies in a dose-dependent manner. The results of simultaneous blood sampling from the aortic sinus, coronary sinus, and right atrium were consistent with the notion that human cMABs are derived from the heart. CONCLUSIONS: Human cMABs are mobilized by heparin injection during cardiac surgery or cardiac catheterization, presumably via HGF upregulation.

Acute myocardial infarction activates progenitor cells and increases Wnt signalling in the bone marrow.

AIMS: We aimed to characterize the influence of acute myocardial infarction (AMI) on the metabolic activity of the bone marrow (BM) and on the composition and functional activity of BM-derived mononuclear cells (BMC). Acute ischaemia or other stressors induce the mobilization of progenitor cells from the BM stem cell niche. The effect of AMI on the numbers and functional activity of cells within the BM is unknown. METHODS AND RESULTS: In patients of the REPAIR-AMI trial as well as in mice, the number and functionality of BMC was compared with respect to the time interval from AMI. Activation of Wnt signalling was assessed after AMI induction in TOP-GAL transgenic reporter mice, carrying a ß-galactosidase gene driven by an LEF/TCF/ß-catenin responsive promoter. The metabolic activity of the BM, as determined by F-18-fluorodeoxyglucose-positron emission tomography, was significantly higher in patients with AMI compared with patients with chronic post-ischaemic heart failure. Moreover, the number of haematopoietic CD34(+) (P < 0.05) and CD133(+) (P < 0.05) cells in the BM aspirates was significantly increased in patients within 7 days after AMI. In order to confirm these clinical data, we induced AMI in mice, which time-dependently increased the number of c-kit + Sca-1 + lin- cells and colony-forming units in the BM. Activation of the BM by AMI induced a significant increase in Wnt signalling, which is known to induce proliferation of haematopoietic stem cells, and demonstrated increased levels of the Wnt target Axin-2 in BM-derived cells on Day 7 (P < 0.01 vs. control). CONCLUSION: Acute myocardial infarction is associated with an increased metabolic activity and increased levels of progenitor cells within days after AMI. These findings document an activation of the stem cell niche within the BM following AMI, which may have important implications for the optimal timing of cell aspirations used for therapeutic application in patients with AMI.

Wnt5a-YAP signaling axis mediates mechanotransduction in cardiac myocytes and contributes to contractile dysfunction induced by pressure overload.

Non-canonical Wnt signaling activated by Wnt5a/Wnt11 is required for the second heart field development in mice. However, the pathophysiological role of non-canonical Wnt signaling in the adult heart has not been fully elucidated. Here we show that cardiomyocyte-specific Wnt5a knockout mice exhibit improved systolic function and reduced expression of mechanosensitive genes including Nppb when subjected to pressure overload. In cultured cardiomyocytes, Wnt5a knockdown reduced Nppb upregulation induced by cyclic cell stretch. Upstream analysis revealed that TEAD1, a transcription factor that acts with Hippo pathway co-activator YAP, was downregulated both in vitro and in vivo by Wnt5a knockdown/knockout. YAP nuclear translocation was induced by cell stretch and attenuated by Wnt5a knockdown. Wnt5a knockdown-induced Nppb downregulation during cell stretch was rescued by Hippo inhibition, and the rescue effect was canceled by knockdown of YAP. These results collectively suggest that Wnt5a-YAP signaling axis mediates mechanotransduction in cardiomyocytes and contributes to heart failure progression.

Sox2 transduction enhances cardiovascular repair capacity of blood-derived mesoangioblasts.

RATIONALE: Complementation of pluripotency genes may improve adult stem cell functions. OBJECTIVES: Here we show that clonally expandable, telomerase expressing progenitor cells can be isolated from peripheral blood of children. The surface marker profile of the clonally expanded cells is distinct from hematopoietic or mesenchymal stromal cells, and resembles that of embryonic multipotent mesoangioblasts. Cell numbers and proliferative capacity correlated with donor age. Isolated circulating mesoangioblasts (cMABs) express the pluripotency markers Klf4, c-Myc, as well as low levels of Oct3/4, but lack Sox2. Therefore, we tested whether overexpression of Sox2 enhances pluripotency and facilitates differentiation of cMABs in cardiovascular lineages. METHODS AND RESULTS: Lentiviral transduction of Sox2 (Sox-MABs) enhanced the capacity of cMABs to differentiate into endothelial cells and cardiomyocytes in vitro. Furthermore, the number of smooth muscle actin positive cells was higher in Sox-MABs. In addition, pluripotency of Sox-MABs was shown by demonstrating the generation of endodermal and ectodermal progenies. To test whether Sox-MABs may exhibit improved therapeutic potential, we injected Sox-MABs into nude mice after acute myocardial infarction. Four weeks after cell therapy with Sox-MABs, cardiac function was significantly improved compared to mice treated with control cMABs. Furthermore, cell therapy with Sox-MABs resulted in increased number of differentiated cardiomyocytes, endothelial cells, and smooth muscle cells in vivo. CONCLUSIONS: The complementation of Sox2 in Oct3/4-, Klf4-, and c-Myc-expressing cMABs enhanced the differentiation into all 3 cardiovascular lineages and improved the functional recovery after acute myocardial infarction.

Hepatocyte growth factor mobilizes non-bone marrow-derived circulating mesoangioblasts.

AIMS: The identification of factors that mobilize subsets of endogenous progenitor cells may provide new therapeutic tools to enhance the repair of ischaemic tissue. We previously identified circulating mesenchymal cells that co-express endothelial markers (so-called circulating mesoangioblasts, cMABs) in children undergoing heart surgery with cardiopulmonary bypass (CPB). However, the mechanisms by which these cells are mobilized and their origin is unclear. METHODS AND RESULTS: Circulating CD73(+)CD45(-)KDR(+) cMABs were analysed in adults undergoing heart surgery with (n = 21) or without CPB (n = 8). During surgery with CPB, cMABs are mobilized with a maximal response at the end of the operation. In contrast, off-pump heart surgery does not stimulate cMAB mobilization, indicating that the stress mediated by CPB induces the mobilization of cMAB. Circulating mesoangioblasts were enriched in blood obtained from the coronary sinus. Histologically, CD73(+) cells were detected around vessels in the heart, indicating that the heart is one of the niches of cMABs. Consistently, studies in gender mismatched bone marrow transplanted patients demonstrated that cMABs did not originate from the bone marrow. Cytokine profiling of serum samples revealed that hepatocyte growth factor (HGF) was profoundly increased at the time point of maximal mobilization of cMABs. Hepatocyte growth factor stimulated the migration of cMABs. Importantly, injection of recombinant HGF increased cMABs in rats. CONCLUSIONS: Hepatocyte growth factor induces mobilization of non-haematopoietic progenitor cells with a cardiac repair capacity. This newly identified function together with the known pleiotrophic effects of HGF makes HGF an attractive therapeutic option for the treatment of ischaemic heart disease.

Comparison of metabolic profile and adiponectin level with pioglitazone versus voglibose in patients with type-2 diabetes mellitus associated with metabolic syndrome.

Type 2 diabetes mellitus (T2DM) associated with metabolic syndrome (MetS) represents a high risk of cardiovascular disease. We compared the effect of early intervention with pioglitazone versus voglibose on physical and metabolic profiles and serum adiponectin level in patients with T2DM associated with MetS. Sixty patients who were diagnosed for the first time as T2DM associated with MetS were analyzed for insulin sensitivity, lipid profile, serum adiponectin and systemic inflammation. Those patients were randomly assigned to oral pioglitazone group (n = 30) or voglibose group (n = 30) in addition to conventional diet and exercise training. Body mass index and waist circumference did not change in the pioglitazone group, whereas these physical parameters significantly decreased in the voglibose group during a 6-month follow-up period. However, glycosylated hemoglobin, fasting plasma glucose, and HOMA-IR more significantly decreased in the pioglitazone group. The level of serum adiponectin especially high-molecular weight adiponectin markedly increased in the pioglitazone group. Moreover, high sensitive CRP significantly decreased only in the pioglitazone group. These results suggest that voglibose is superior in improving obesity, while pioglitazone is superior in ameliorating insulin sensitivity and increasing serum adiponectin in patients with an early stage of T2DM associated with MetS.

Interleukin-10 from transplanted bone marrow mononuclear cells contributes to cardiac protection after myocardial infarction.

Bone marrow mononuclear cells (BM-MNCs) have successfully been used as a therapy for the improvement of left ventricular (LV) function after myocardial infarction (MI). It has been suggested that paracrine factors from BM-MNCs may be a key mechanism mediating cardiac protection. We previously performed microarray analysis and found that the pleiotropic cytokine interleukin (IL)-10 was highly upregulated in human progenitor cells in comparison with adult endothelial cells and CD14+ cells. Moreover, BM-MNCs secrete significant amounts of IL-10, and IL-10 could be detected from progenitor cells transplanted in infarcted mouse hearts. Specifically, intramyocardial injection of wild-type BM-MNCs led to a significant decrease in LV end-diastolic pressure (LVEDP) and LV end-systolic volume (LVESV) compared to hearts injected with either diluent or IL-10 knock-out BM-MNCs. Furthermore, intramyocardial injection of wild-type BM-MNCs led to a significant increase in stroke volume (SV) and rate of the development of pressure over time (+dP/dt) compared to hearts injected with either diluent or IL-10 knock-out BM-MNCs. The IL-10-dependent improvement provided by transplanted cells was not caused by reduced infarct size, neutrophil infiltration, or capillary density, but rather was associated with decreased T lymphocyte accumulation, reactive hypertrophy, and myocardial collagen deposition. These results suggest that BM-MNCs mediate cardiac protection after myocardial infarction and this is, at least in part, dependent on IL-10.

Notch signaling contributes to the expression of cardiac markers in human circulating progenitor cells.

It has been demonstrated that adult human circulating endothelial progenitor cells (EPCs) can differentiate to a cardiomyogenic phenotype. Notch signaling promotes epithelial-to-mesenchymal transformation and plays a role in heart and vessel development. Here, we investigated the role of Notch activation for cardiac differentiation of EPCs in a coculture system with neonatal cardiomyocyte. After coculture, Notch activation was transiently detected in EPCs, as determined by immunohistochemical detection of NICD (the intracellular cleavage fragment of Notch-1) and expression of human Notch target genes. Inhibition of gamma-secretase blocked Notch cleavage and NICD translocation. Furthermore, the expression of the cardiac marker protein alpha-sarcomeric actinin and troponin T was significantly suppressed by gamma-secretase inhibition or addition of soluble recombinant Jagged-1, indicating that Notch activation facilitates cardiac marker gene expression. Because noncanonical Wnts have previously been shown to promote cardiac differentiation, we additionally determined the influence of Notch activation on the expression of Wnt5a and Wnt11. Wnt5a and Wnt11 expression in the human cells was induced by the coculture and was blocked by gamma-secretase inhibition. Likewise, stimulation of Notch signaling by immobilized Jagged-1 promoted Wnt5a expression in EPCs. These data suggest that Notch is activated upon coculture of EPCs with neonatal rat cardiac myocytes. Gamma-secretase-dependent Notch activation is required for cardiac gene expression in human cells and induces the expression of noncanonical Wnt proteins, which may act in a paracrine manner to further amplify cardiac differentiation.

Characterization of long-term endogenous cardiac repair in children after heart transplantation.

AIMS: Circulating cells repopulate the heart at a very low rate in adult humans. The knowledge about time-dependent cardiac regeneration is very limited and the contribution of circulating cells to cardiomyocytes or vascular cells in children is unknown. This study investigates the endogenous repair capacity and the long-term incorporation of circulating cells in heart-transplanted children. METHODS AND RESULTS: Cardiac and endothelial chimerism was detected in endomyocardial biopsies of nine children (age 1 months-14 years) with sex-mismatched heart transplantation by fluorescence in situ hybridization. Time from transplantation to biopsy ranged from 1 month up to 10 years. The extent of repopulating cardiomyocytes was 2.39 +/- 1.54% (range: 0-4.2%) and correlated significantly with the time from transplantation to biopsy sampling (r(2) = 0.69, P = 0.006; n = 9). The calculated contribution of male cardiomyocytes in the female heart per year was 0.36 +/- 0.09%. Consistent with the previous reports, the incorporation of vascular cells was higher compared with cardiomyocytes (14.4 +/- 4.17%), but did not correlate in a time-dependent manner. CONCLUSION: Circulating cells contribute to cardiomyocytes and endothelial cells in children after heart transplantation. The incidence of repopulating cardiomyocytes continuously increases in a time-dependent manner ( approximately 4% Y-chromosome(+) cardiomyocytes/10 years) and resembles the cardiac regeneration activity observed in adults.

Administration of granulocyte colony-stimulating factor to recipients followed by intra-bone marrow-bone marrow transplantation accelerates acceptance of allogeneic bone marrow cells in mice.

We have recently established a novel method for bone marrow transplantation: intra-bone marrow-bone marrow transplantation (IBM-BMT), by which the rapid recovery of donor-derived hematopoiesis can be expected even when reduced radiation doses are used. In this paper, we examine, using mice, whether the combination of pretreatment of recipients with granulocyte-colony-stimulating factor (G-CSF) and IBM-BMT can induce a more rapid recovery of donor-derived hematopoiesis than IBM-BMT alone. We first pretreated recipients with recombinant human (rh) G-CSF (250 microg/kg/day) for 5 consecutive days (days -6 to -2). On day -1, the recipients were irradiated, and IBM-BMT was carried out on day 0. On day 12, we performed colony-forming units of spleen (CFU-S) assays. The combination of G-CSF pretreatment and IBM-BMT augmented the CFU-S counts, the weight of spleens, and the numbers of donor-derived hematopoietic cells. We next analyzed the mechanisms underlying these effects of G-CSF and found that (i) G-CSF induces Th2 polarization, which can prevent graft rejection, and (ii) G-CSF augments natural suppressor activity, which suppresses graft rejection. The combination of G-CSF pretreatment and IBM-BMT can produce the rapid recovery of donor-derived hematopoiesis and suppress graft rejection. This method would lighten the burden on patients in allogeneic BMT.

FKBP51 expressed by both normal epithelial cells and adenocarcinoma of colon suppresses proliferation of colorectal adenocarcinoma.

It has been reported, as a result of Western blot analyses, that FKBP51 is expressed in various tissues, but that it is not expressed in the pancreas, lung, colon, stomach, or spleen. In this paper, we show, using Western blot analyses, reverse transcriptase polymerase chain reaction, and immunohistochemical analyses of samples from colon cancer patients, that both normal epithelial cells and adenocarcinoma in the human colon express FKBP51, and that there are no significant differences in the expressions of FKBP51 between them. We also show that FKBP51 suppresses the proliferation of colorectal adenocarcinoma, possibly due to the suppression of functions of the glucocorticoid receptors.

Immunotherapy for malignant tumors using combination of allogeneic intra-bone marrow-bone marrow transplantation, donor lymphocyte infusion and dendritic cells.

We have previously shown that the combination of allogeneic intra-bone marrow-bone marrow transplantation (IBM-BMT) and donor lymphocyte infusion (DLI) using CD4+ cell-depleted spleen cells is effective in suppressing tumor growth, but that this does not induce graft-versus-host disease (GVHD) in mice. In this report, we show that formalin-fixed tumor cell-pulsed dendritic cells (FFTCP DCs) have an additive effect with IBM-BMT plus DLI on the suppression of tumor growth, but that the DCs do not augment GVHD. BALB/c mice, which had been subcutaneously inoculated with Meth A (BALB/c-derived fibrosarcoma), were irradiated at a low dose (5 Gy) and were transplanted with bone marrow cells (BMCs) from C57BL/6 (B6) mice into the bone marrow cavity (IBM-BMT). Simultaneously, the mice were intravenously injected with spleen cells from B6 mice, and subcutaneously injected with FFTCP DCs derived from the bone marrow (BM) of B6 mice. At the point of the induction of DCs from BMCs, formalin-fixed Meth A cells were added into the culture. The mice treated with the combination of FFTCP DCs, IBM-BMT and DLI using CD4+ cell-depleted spleen cells showed smaller tumor sizes and longer survival than the mice treated with IBM-BMT plus FFTCP DCs or IBM-BMT plus DLI using CD4+ cell-depleted spleen cells. These results suggest that the combination of FFTCP DCs, IBM-BMT plus DLI using CD4+ cell-depleted spleen cells has potent anti-tumor effects without showing GVHD.

An innovative approach to bone marrow collection and transplantation in a patient with beta-thalassemia major: marrow collection using a perfusion method followed by intra-bone marrow injection of collected bone marrow cells.

Using small animals (mice and rats) and monkeys, we have found that the combination of bone marrow collection using the perfusion method (PM) and intra-bone marrow-bone marrow transplantation (IBM-BMT) of the collected cells is safe and effective in treating various intractable diseases. Based on these findings, we attempted to apply this method to humans. We report here the first case of a patient (6 years old) with beta-thalassemia major who underwent allogeneic BMT using this new PM + IBM-BMT method. The white blood cell counts of the patient gradually increased to more than 1500/microL by day 47 and continued to increase, reaching the highest level (8600/microL) on day +55. Fluorescence in situ hybridization data on day +33 showed that 98% of the peripheral blood cells were from the donor. Notably, there were no symptoms of graft-versus-host disease (GvHD). However, on day +56, the patient regrettably died of asphyxia resulting from sticky sputum. There was no evidence of infection (in the lung or liver) or GvHD (in the skin) by necropsy. We hope that this case report will help make our new strategies more readily available for the treatment of patients with various intractable diseases.

Effects of low-dose irradiation on enhancement of immunity by dendritic cells.

Low-doses of irradiation have been reported to have beneficial effects, particularly anti-tumor effects. In this paper, we show the effects of the low-dose irradiation on T cell activation induced by dendritic cells (DCs). DCs, which had been pre-irradiated at 0.02-1.0 Gy from a (137)Cs source, were cultured with allogeneic T cells, and the proliferation of T cells was then examined. The 0.05Gy-pre-irradiated DCs showed the highest proliferation capacity of T cells. The 0.05Gy-irradiation does not augment the expression of major histocompatibility complexes (MHCs) or costimulatory molecules on DCs, as with non-irradiated DCs or 1Gy-irradiated DCs, but does augment the production of IL-2, IL-12 and IFN-gamma DCs. These results suggest that the low-dose irradiation augments T cell-activation capacity through cytokine production by DCs, which might shift naïve helper T cells to Th1 cells.

Human cord blood cells can differentiate into retinal nerve cells.

Retinal degeneration and dystrophy are the major causes of blindness in the developed world. It has been reported that human cord blood cells (HCBCs) can differentiate into neuron-like cells in vitro. We have recently demonstrated that bone marrow cells (BMCs) of both mice and rats can differentiate into retinal nerve cells (RNCs). In the present study, we show the differentiation capacity of HCBCs into RNCs in vivo. We transplanted lineage-negative HCBCs into the subretinal space of severe combined immunodeficiency (SCID) mice. Two weeks after the transplantation, some of the transplanted cells expressed human nestin, human MAP2, human neuron specific enolase (NSE), beta-III tubulin and also rhodopsin. These results indicate that HCBCs can differentiate into RNCs and suggest that our new strategy could be used for the regeneration of retinal nerve cells in degenerative or dystrophic diseases.

G-CSF and/or M-CSF accelerate differentiation of bone marrow cells into endothelial progenitor cells in vitro.

It has been reported that granulocyte-colony stimulating factor (G-CSF) and granulocyte-macrophage-colony stimulating factor (GM-CSF) can mobilize endothelial progenitor cells (EPCs) in bone marrow cells (BMCs) into peripheral blood (PB) in vivo. Previously, we also reported that macrophage-colony stimulating factor (M-CSF) can mobilize EPCs into PB, which results in the rapid recovery of blood flow in induced-ischemia limbs by augmenting the number of intramuscular capillaries in vivo. In the present study, we demonstrate that M-CSF and/or G-CSF can increase EPCs from lineage (CD3, B220, Gr-1, Mac-1, CD11c, Ter119, NK1.1 or CD31)-negative BMCs in vitro. Lineage-negative BMCs were cultured with or without M-CSF and/or G-CSF. Three days after culture with M-CSF and/or G-CSF, the number of Flk-1+/CD45-, Sca-1+/CD45-, CD31+/CD45- or CD146+/CD45- cells increased in comparison with no cytokines. When the cultured BMCs with or without G-CSF and/or M-CSF were intravenously injected into ischemia-induced hindlimbs of mice, the number of intramuscular capillaries in the ischemia-induced legs increased; BMCs cultured with G-CSF and/or M-CSF were more effective than those of cytokine non-treated BMCs. These results suggest that M-CSF and/or G-CSF can induce the differentiation of BMCs into EPCs, even in vitro.

Synergistic effects of granulocyte-colony stimulating factor and macrophage-colony stimulating factor on recovery of donor hematopoietic cells in allogeneic bone marrow transplantation.

G-CSF and M-CSF are used clinically to augment hematopoiesis after bone marrow transplantation (BMT) and chemotherapy. In this paper, we examined the synergistic effect of G-CSF and M-CSF on hematopoietic recovery in allogeneic BMT as a model of human BMT. We performed BMT from eGFP-transgenic mice (C57BL/6 background; H-2b) into lethally-irradiated C3H (H-2k). From the day after BMT, G-CSF and/or M-CSF were injected for 5 consecutive days. Not only the numbers of day 12 CFU-S and spleen weight, but also white blood cell (WBC) counts in the peripheral blood (PB) and nuclear cells in the bone marrow (BM) increased in the mice treated with G-CSF and/or M-CSF 12 days after BMT. Moreover, the number of donor-type WBCs in the PB and donor-type nuclear cells in the BM also increased in the mice treated with G-CSF and/or M-CSF. The effects were pronounced when G-CSF and M-CSF were used together rather than independently. These results suggest that treatment with the combination of G-CSF and M-CSF has a synergistic effect on hematopoiesis in allogeneic BMT.

Antagomir-92a impregnated gelatin hydrogel microsphere sheet enhances cardiac regeneration after myocardial infarction in rats.

INTRODUCTION: We investigated whether attachment of gelatin hydrogel microsphere (GHM) sheet impregnated with antagomir-92a on the infarcted heart promotes angiogenesis and cardiomyogenesis, and improves cardiac function after myocardial infarction (MI) in rats. METHODS: GHM sheet impregnated with antagomir-92a, its scramble sequence antagomir-control sheet or the sheet alone was attached on the area at risk of MI after the left anterior descending coronary artery ligation. Bromodeoxyuridine (BrdU) was included in the sheet to trace proliferating cells. RESULTS: The antagomir-92a sheet significantly increased capillary density in the infarct border zone 14 days after MI compared to the antagomir-control sheet or the sheet alone, associated with an increase in endothelial cells incorporated with BrdU. The antagomir-92a sheet significantly increased cardiac stem cells incorporated with BrdU 3 days after MI in the infarct border zone. This was associated with an increase in cardiomyocytes incorporated with BrdU 14 days after MI. Scar area was significantly reduced by the antagomir-92a sheet compared to the antagomir-control sheet or the sheet alone (12.8 ± 1.3 vs 25.2 ± 2.2, 24.0 ± 1.7% LV area, respectively) 14 days after MI. LV dilatation was inhibited, and LV wall motion was improved 14 days after MI in rats with the antagomir-92a sheet compared to the antagomir-control sheet or the sheet alone. CONCLUSIONS: These results suggest that attachment of the GHM sheet impregnated with antagomir-92a on the area at risk of MI enhances angiogenesis, promotes cardiomyogenesis, and ameliorates LV function.