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Background: Extensive studies have attempted to clarify the contribution of bone marrow-derived cells to the regeneration of various organs, but not the lungs. We evaluated the role of bone marrow-derived cells in compensatory regenerative lung growth., Methods: We induced regenerative lung growth by left pneumonectomy in adult C57BL/6 mice. To evaluate the role of bone marrow-derived cells in lung regenerative growth, green fluorescent protein (GFP)-positive, bone marrow-transplanted chimeric mice underwent inhibition of stromal-cell-derived factor (SDF)-1α/CXCR4 signaling by 7-d continuous administration of a CXCR4 antagonist after pneumonectomy., Results: Left pneumonectomy resulted in a significant increase in lung dry weight, as well as an increase in lung volume, without enlargement of the alveolar air space. We observed GFP-positive cells 2.1-fold more frequently in the lungs of pneumonectomized mice versus sham-operated mice by immunohistochemistry (P = 0.001), although only a proportion of these accumulated cells possessed a pneumocyte-like appearance. Pneumonectomy induced a 1.4-fold increase in the SDF-1α level in the remaining lung at 7 d compared with sham-operated mice (P < 0.05), although pneumonectomy was not accompanied by histopathological lung injury. Blockade of SDF-1α/CXCR4 signaling resulted in a significant reduction in the accumulation of GFP-positive cells in the remaining lung at 7 d and prevented regenerative lung growth, as shown by a 10% reduction in lung dry weight at 14 d compared with control pneumonectomized mice (P < 0.05)., Conclusions: Bone marrow-derived cells have a significant role in compensatory regenerative lung growth in an adult mouse model. Further evaluation to clarify molecular interactions between bone marrow-derived cells and pneumocytes should prove fruitful., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Objectives: The goal of this study was to conduct a direct head-to-head comparison of different stem cell types in vitro for various assays of potency and in vivo for functional myocardial repair in the same mouse model of myocardial infarction., Background: Adult stem cells of diverse origins (e.g., bone marrow, fat, heart) and antigenic identity have been studied for repair of the damaged heart, but the relative utility of the various cell types remains unclear., Methods: Human cardiosphere-derived cells (CDCs), bone marrow-derived mesenchymal stem cells, adipose tissue-derived mesenchymal stem cells, and bone marrow mononuclear cells were compared., Results: CDCs revealed a distinctive phenotype with uniform expression of CD105, partial expression of c-kit and CD90, and negligible expression of hematopoietic markers. In vitro, CDCs showed the greatest myogenic differentiation potency, highest angiogenic potential, and relatively high production of various angiogenic and antiapoptotic-secreted factors. In vivo, injection of CDCs into the infarcted mouse hearts resulted in superior improvement of cardiac function, the highest cell engraftment and myogenic differentiation rates, and the least-abnormal heart morphology 3 weeks after treatment. CDC-treated hearts also exhibited the lowest number of apoptotic cells. The c-kit(+) subpopulation purified from CDCs produced lower levels of paracrine factors and inferior functional benefit when compared with unsorted CDCs. To validate the comparison of cells from various human donors, selected results were confirmed in cells of different types derived from individual rats., Conclusions: CDCs exhibited a balanced profile of paracrine factor production and, among various comparator cell types/subpopulations, provided the greatest functional benefit in experimental myocardial infarction., (Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Delayed wound healing is a serious clinical problem in patients after surgery. A recent study has demonstrated that bone marrow-derived c-kit-positive (c-kit(+)) cells play important roles in repairing and regenerating various tissues and organs. To examine the hypothesis that surgical injury induces the mobilization and recruitment of c-kit+ cells to accelerate wound healing. Mice were subjected to a left pneumonectomy. The mobilization of c-kit+ cells was monitored after surgery. Using green fluorescent protein (GFP(+)) bone marrow-transplanted chimera mice, we investigated further whether the mobilized c-kit+ cells were recruited to effect wound healing in a skin puncture model. The group with left pneumonectomies increased the c-kit(+) and CD34(+) stem cells in peripheral blood 24 h after surgery. At 3 days after surgery, the skin wound size was observed to be significantly smaller, and the number of bone marrow-derived GFP(+) cells and GFP(+)/c-kit+ cells in the wound tissue was significantly greater in mice that had received pneumonectomies, as compared with those that had received a sham operation. Furthermore, some of these GFP(+) cells were positively expressed specific markers of macrophages (F4/80), endothelial cells (CD31), and myofibroblasts (αSMA). The administration of AMD3100, an antagonist of a stromal-cell derived factor (SDF)-1/CXCR4 signaling pathway, reduced the number of GFP(+) cells in wound tissue and completely negated the accelerated wound healing. Surgical injury induces the mobilization and recruitment of c-kit+ cells to contribute to wound healing. Regulating c-kit+ cells may provide a new approach that accelerates wound healing after surgery.

Background: Hypoxic preconditioning of bone marrow cells (BMCs) from young healthy individuals can enhance the cells' therapeutic potential. Considering that the response to hypoxia may differ according to the quality of the cells, we assessed the effect of hypoxic preconditioning on BMCs from aged mice and compared the difference in response between BMCs from aged and young mice., Methods and Results: BMCs from young (3 months) and aged (20-22 months) mice were subjected to hypoxic preconditioning by culture for 24 h in 2% O₂. Compared with BMCs from young mice, those from aged mice showed significantly fewer CD34- or c-kit-positive stem cells, higher expression of p53, and lower telomerase activity. Adhesion, survival and angiogenic potency were also lower in BMCs from aged mice, indicating an aging-related impairment. Hypoxia-preconditioned BMCs from aged mice showed enhanced adhesion, survival, and angiogenic potency with the in vitro assessments, as well as the in vivo implantation into ischemic hindlimbs. All the enhancements by hypoxic preconditioning were comparable between BMCs from aged and young mice, although the angiogenic potential of BMCs with and without hypoxic preconditioning was lower in old mice compared with young mice., Conclusions: Similar responses to hypoxia by BMCs from both aged and young mice suggest that hypoxic preconditioning could be a useful method of enhancing the angiogenic potential of BMCs.

Bone marrow (BM)-derived stem/progenitor cells play an important role in ischemia-induced angiogenesis in cardiovascular diseases. Heat shock factor 1 (HSF1) is known to be induced in response to hypoxia and ischemia. We examined whether HSF1 contributes to ischemia-induced angiogenesis through the mobilization and recruitment of BM-derived stem/progenitor cells using HSF1-knockout (KO) mice. After the induction of ischemia, blood flow and microvessel density in the ischemic hindlimb were significantly lower in the HSF1-KO mice than in the wild-type (WT) mice. The mobilization of BM-derived Sca-1- and c-kit-positive cells in peripheral blood after ischemia was significantly lower in the HSF1-KO mice than in the WT mice. BM stem/progenitor cells from HSF1-KO mice showed a significant decrease in their recruitment to ischemic tissue and in migration, adhesion, and survival when compared with WT mice. Blood flow recovery in the ischemic hindlimb significantly decreased in WT mice receiving BM reconstitution with donor cells from HSF1-KO mice. Conversely, blood flow recovery in the ischemic hindlimb significantly increased in HSF1-KO mice receiving BM reconstitution with donor cells from WT mice. These findings suggest that HSF1 contributes to ischemia-induced angiogenesis by regulating the mobilization and recruitment of BM-derived stem/progenitor cells.

Background: Although operative injury is thought generally to worsen the prognosis of cancer patients, the relevant mechanisms are not yet understood fully. We tested the hypothesis that operative injury induces mobilization and recruitment of bone marrow stem cells, thereby enhancing angiogenesis and accelerating tumor growth., Methods: Mice were subjected to an open gastrotomy, and naïve mice were used as controls. The mobilization of bone marrow stem cells was monitored after operation. Using an established tumor model in green fluorescent protein (GFP)(+) bone marrow-transplanted chimera mice, we investigated further whether the mobilized stem cells affected tumor growth., Results: Compared with the control, gastrotomy increased the populations of CD34(+) cells (6.9 ± 4.5 % vs 3.3 ± 0.4%, P < .05) and CD34(+)/Flk-1(+) cells (0.08 ± 0.02% vs 0.05 ± 0.01%, P < .05) in peripheral blood 12 h after operation. Twelve days after operation, the tumor volume almost doubled in mice after gastrotomy compared with control (580 ± 106 mm(3) vs 299 ± 162 mm(3), P < .05). A histologic analysis of tumor tissue revealed that the microvessel density and number of proliferating cells were significantly greater, but those of apoptotic cells were significantly less, in mice after gastrotomy as compared with control. Furthermore, the number of GFP(+) cells found in tumor tissue was significantly greater in mice that underwent gastrotomy than in controls. Some of the stained GFP(+) cells were positive for CD34 and had been incorporated into microvessels. Administration of AMD3100, which is an antagonist of stromal-cell-derived factor (SDF)-1/CXCR4 signaling pathway, inhibited the recruitment of GFP(+) cells and negated completely the acceleration in tumor growth after operation (345 ± 172 mm(3), P < .05)., Conclusion: Operative injury may induce the mobilization and recruitment of bone marrow stem cells, thereby enhancing angiogenesis and accelerating tumor growth. Inhibition of the SDF-1/CXCR4 signals may represent a new therapeutic strategy for preventing acceleration of tumor growth after operation., (Copyright © 2011 Mosby, Inc. All rights reserved.)

Bone marrow stem cells from diabetes mellitus patients exhibit functional impairment, but the relative molecular mechanisms responsible for this impairment are poorly understood. We investigated the mechanisms responsible for diabetes-related functional impairment of bone marrow stem cells by extensively screening the expression levels of inflammatory factors, cell cycle regulating molecules, extracellular matrix molecules and adhesion molecules. Bone marrow cells were collected from type 2 diabetic (db/db) and healthy control (db/m+) mice, and c-kit+ stem cells were purified (purity>85%) for experiments. Compared with the healthy control mice, diabetic mice had significantly fewer c-kit+ stem cells, and these cells had a lower potency of endothelial differentiation; however, the production of the angiogenic growth factor VEGF did not differ between groups. A pathway-focused array showed that the c-kit+ stem cells from diabetic mice had up-regulated expression levels of many inflammatory factors, including Tlr4, Cxcl9, Il9, Tgfb1, Il4, and Tnfsf5, but no obvious change in the expression levels of cell cycle molecules. Interestingly, diabetes-related alterations of the extracellular matrix and adhesion molecules were varied; Pecam, Mmp10, Lamc1, Itgb7, Mmp9, and Timp4 were up-regulated, but Col11a1, Fn1, Admts2, and Itgav were down-regulated. Some of these changes were also confirmed at the protein level by flow cytometry analysis. In conclusion, c-kit+ bone marrow stem cells from diabetic mice exhibited an extensive enhancement of inflammatory factors and disorders of the extracellular matrix and adhesion molecules. Further intervention studies are required to determine the precise role of each molecule in the diabetes-related functional impairment of c-kit+ bone marrow stem cells.

Objective: The implantation of autologous bone marrow-derived cells has been used for the treatment of ischemic diseases, but obvious interindividual differences were observed in the improvement of regional perfusion and cardiac function after treatment. We examined the angiogenic potency of bone marrow cells from patients with different clinical backgrounds., Methods: Bone marrow cells were collected from 25 patients scheduled to undergo sternotomy for various surgical procedures. We examined the quality of bone marrow cells and investigated their angiogenic potency by using an ischemic limb model in mice with severe combined immunodeficiency., Results: When compared with their control cohort, bone marrow cells from patients with advanced age, renal failure, or anemia had significantly less c-kit- and CD34-positive stem cells (P < .05) and showed significantly lower vascular endothelial growth factor production and colony-forming units in culture (P < .05). Furthermore, the implantation of bone marrow cells from patients with advanced age, renal failure, or anemia into the ischemic limbs of mice also resulted in significantly worse blood flow recovery and clinical score when compared with the implantation of bone marrow cells from their control cohorts (P < .05). However, the bone marrow cells from patients with diabetes and hypertension did not show significant impairment of angiogenic potency when compared with their control cohorts., Conclusions: The quality and angiogenic potency of bone marrow cells differs among patients. Advanced age, renal failure, and anemia should be the risk factors related to poor angiogenic potency of bone marrow cells for the treatment of ischemic diseases., (2010 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

Background: Therapeutic angiogenesis induced by the implantation of autologous bone marrow-derived cells has been used for the treatment of ischemic diseases. However, as the outcomes of cell implantation obviously vary among patients, it is essential to identify patients that would benefit the most from this treatment., Methods and Results: We collected clinical and laboratory data from 25 patients scheduled to undergo sternotomy for various surgical procedures. Then, we aspirated bone marrow cells from the sternum during the operation and investigated the cell quality in vitro by cultivation, and their angiogenic potency in vivo using an ischemic limb model of mice. The angiogenic potency of bone marrow cells differed among patients. Aging, renal failure, anemia, and high serum levels of triglyceride, C-reactive protein, interleukin-6, and type I collagen cross-linked N-telopeptide (NTX) significantly correlated with poor angiogenic potency of bone marrow cells. We assigned scores to these risk factors, and found a strong correlation between the risk scores of patients and the angiogenic potency of their bone marrow cells (r=-0.883, P<0.001). These risk scores can predict the angiogenic potency of bone marrow cells for inducing therapeutic angiogenesis with an accuracy of 80%., Conclusions: We have identified the risk factors related to poor angiogenic potency of bone marrow cells and developed a new scoring system to predict their angiogenic potency for the treatment of ischemic diseases. Our results may help select patients for this treatment in future clinical trials.

Objectives: The aim of this study was to investigate whether the mobilization and recruitment of bone marrow stem cells (BMSCs) contribute to cardioprotection in the late phase after ischemic pre-conditioning (IPC)., Background: IPC is an innate phenomenon in which brief exposure to sublethal ischemia provides tissue protection from subsequent ischemia/reperfusion (I/R) injury. A delayed cardioprotection also occurs after IPC, but the precise mechanism is unclear., Methods: IPC was created with 4 cycles of 5-min occlusion and reperfusion of the abdominal aorta in mice. Heart I/R injury was induced by occluding the left anterior descending artery for 30 min immediately (early phase) or 24 h (late phase) after IPC., Results: Serum vascular endothelial growth factor and stromal cell-derived factor-1alpha levels were increased significantly 1 and 3 h after IPC, but CD34+ and CD34+/flk-1+ stem cells in the peripheral blood were increased significantly 12 and 24 h after IPC (p < 0.05). Compared with the control treatment, both the early and late phases of IPC protected the heart against I/R injury. However, the recruitment of BMSCs was significantly greater in the heart when I/R injury was induced in late phase than in the early phase of IPC (p < 0.01). Interestingly, the blockade of the recruitment of BMSCs significantly attenuated the cardioprotective effect of IPC in the late phase (p < 0.01) but did not change in the early phase., Conclusions: Cardioprotection was observed in the early and late phases of IPC; however, the enhanced mobilization and recruitment of BMSCs played an important role in the late phase of IPC.

Background: Bone marrow cells from humans and animals with diabetes exhibit decreased angiogenic potency, thought to be related to oxidative stress, so the present study investigated if antioxidant therapy would attenuate the diabetes-related impairment., Methods and Results: Diabetic mice were given antioxidant therapy, as a daily subcutaneous injection of superoxide dismutase-mimic (10 mg kg(-1) day(-1)). Diabetic and healthy mice given a vehicle treatment were used as the control. After 4 weeks of treatment, bone marrow mononuclear cells (BM-MNCs) were collected for analysis and the endothelial progenitor cells in BM-MNCs were evaluated by flow cytometry. The intracellular reactive oxygen species (ROS) levels in BM-MNCs were measured using 6-carboxy-2'7'-dichlorodihydrofluorescein diacetate. Endothelial differentiation from the BM-MNCs was estimated by immunostaining with VE-cadherin 7 days after culture. BM-MNCs from the control diabetic mice had fewer Flk-1/CD34 double-positive progenitor cells and higher intracellular ROS levels, with lower potency of endothelial differentiation than BM-MNCs from the healthy mice. Antioxidant therapy decreased the intracellular ROS level in BM-MNCs from that in the diabetic mice significantly (P<0.05), but increased significantly the percentage of endothelial progenitor cells (P<0.05) and their potency of differentiation into endothelial cells (P<0.05)., Conclusions: Antioxidant therapy attenuated the diabetes-related impairment of BM-MNCs by reducing oxidative stress.

Transforming growth factor-beta(1) (TGF-beta(1)) was found to induce the myogenic differentiation of bone marrow stem cells (BMSC). We investigated the morphological and electrophysiological properties of differentiated cells, and the mechanisms related to TGF-beta(1)-induced myogenic differentiation. We found that TGF-beta increased the expression of the cardiac transcription factors, GATA-4 and NKx-2.5, in BMSC after 1-3 days of cultivation. TGF-beta also induced the expressions of cardiac myosin, troponins, and ANP after 3-14 days of cultivation. However, the Ca(2+) transient was relatively weak, the connexin-43 expression was irregular, and spontaneous beating was not detected within 28 days observation. TGF-beta stimulation up-regulated most of the TGF-beta BMP signaling pathway genes, including TGFBI, ACVR2B, and phosphorylated Smad-2 and Smad-3, within 24h. TGF-beta induced the differentiation of BMSC into immature cardiomyocytes by activating the TGF-beta BMP signaling pathway.

Various cytokines produced by bone marrow cells can protect adult cardiomyocytes against apoptosis. Thus, we investigated the feasibility of implanting adult cardiomyocytes in combination with bone marrow cells for myocardial repair. Ventricular cardiomyocytes were isolated from adult rats and cocultured with bone marrow cells. Using a rat model of doxorubicin-induced cardiomyopathy, we injected 6 x 10(5) adult cardiomyocytes, 3 x 10(7) bone marrow cells, or both into damaged hearts, for myocardial repair. Coculture of the cardiomyocytes with the bone marrow cells enhanced the expression of integrin-beta1D and focal adhesion kinase in cardiomyocytes, resulting in increased survival and decreased apoptosis of the cardiomyocytes after 7 days of culture. Compared with the baseline levels, cardiac function was preserved by the implantation of bone marrow cells alone and by the implantation of cardiomyocytes in combination with bone marrow cells, but it was decreased significantly 28 days after the implantation of cardiomyocytes alone. Furthermore, apoptosis of the host cardiomyocytes was decreased significantly after the implantation of bone marrow cells alone, or in combination with cardiomyocytes, compared with that after the implantation of cardiomyocytes alone (p < 0.01). Interestingly, the implantation of adult cardiomyocytes in combination with bone marrow cells resulted in a dramatic increase in the survival of donor cardiomyocytes, and induced the myogenic differentiation of donor bone marrow stem cells. Our findings indicate that cardiomyocytes and bone marrow cells can assist and compliment each other; thus, the implantation of adult cardiomyocytes in combination with bone marrow cells shows promise as a feasible new strategy for myocardial repair.

Therapeutic angiogenesis can be induced by the implantation of bone marrow cells (BMCs). Hydrogen peroxide (H(2)O(2)) has been shown to increase VEGF expression and to be involved in angiogenesis. We tested the hypothesis that pretreatment with H(2)O(2) enhances the efficacy of BMCs for neovascularization. H(2)O(2) pretreatment was done by incubating mouse BMCs in 5 microM H(2)O(2) for 30 min, followed by washing twice with PBS. The H(2)O(2)-pretreated and untreated BMCs were then studied in vitro and in vivo. RT-PCR analysis showed that expression of VEGF and Flk-1 mRNA was significantly higher in H(2)O(2)-pretreated BMCs than in untreated BMCs after 12 and 24 h of culture (P<0.01). Pretreatment with H(2)O(2) also effectively enhanced the VEGF production and endothelial differentiation from BMCs after 1 and 7 days of culture (P<0.05). To estimate the angiogenic potency in vivo, H(2)O(2)-pretreated or untreated BMCs were intramuscularly implanted into the ischemic hindlimbs of mice. After 14 days of treatment, many of the H(2)O(2)-pretreated BMCs were viable, showed endothelial differentiation, and were incorporated in microvessels. Conversely, the survival and incorporation of the untreated BMCs were relatively poor. Microvessel density and blood flow in the ischemic hindlimbs were significantly greater in the mice implanted with H(2)O(2)-pretreated BMCs than in those implanted with untreated BMCs (P<0.05). These results show that the short-term pretreatment of BMCs with low-dose H(2)O(2) is a novel, simple, and feasible method of enhancing their angiogenic potency.

Background: Therapeutic angiogenesis for ischemic diseases has been successfully induced by the implantation of autologous bone marrow cells (BMCs). It is understood that interleukin (IL)-1beta increases remarkably in ischemic tissue and has particular effects on angiogenesis. Thus, it is important to clarify how IL-1beta would effect BMCs survival and angiogenic potential., Methods and Results: The effect of IL-1beta on BMCs survival, adhesion, and endothelial differentiation, as well as the production of angiogenic growth factors, was investigated using an in vitro assessment approach. BMCs were harvested from Zucker obese rats and cultured at a density of 3x10(6) cells/ml with 5 ng/ml IL-1 beta (IL-1beta group) or without IL-1 beta (control group). Survival and adhesion of BMCs were significantly increased in the IL-1beta group than in the control group after 1, 3, and 7 days of culture (p<0.01). The release of vascular endothelial growth factor in supernatant was also significantly higher in the IL-1beta group than in the control group after 3 and 7 days of culture (p<0.01). Furthermore, the number of differentiated endothelial cells derived from BMCs was significantly higher in the IL-1beta group than in the control group after 7 days of culture (p<0.01)., Conclusions: These results suggest that IL-1beta has a positive effect on the angiogenic potential of BMCs in vitro.

It is well known that the implantation of bone marrow mononuclear cells (BM-MNCs) into ischemic hearts can induce angiogenesis and improve cardiac function after myocardial infarction, but the precise mechanisms of these actions are unclear. We hypothesize that the cytokines produced by BM-MNCs play a key role in this cell-based therapy. BM-MNCs from rats were cultured under normoxic or hypoxic (1% O2) conditions for 24 h, and then supernatants were collected for study. ELISA and Western blotting analysis showed that various cytokines, including VEGF, IL-1 beta, PDGF, and IGF-1, were produced from BM-MNCs, some of which were enhanced significantly under hypoxia stimulation. When compared with a control blank medium, the supernatants of BM-MNCs cultured under normoxic or hypoxic conditions inhibited apoptosis significantly and preserved the contractile capacity of isolated adult rat cardiomyocytes in vitro (P < 0.05). Using a rat model of acute myocardial infarction, we injected the supernatants of BM-MNCs or control medium intramyocardially on day 0 and then intraperitoneally on days 2, 4, and 6 after infarction. When compared with the control medium, the supernatants of BM-MNCs cultured under both normoxic or hypoxic conditions increased the microvessel density and decreased the fibrotic area in the infarcted myocardium significantly, contributing to remarkable improvement in cardiac function. Various cytokines were produced by BM-MNCs, and these cytokines contributed to functional improvement of the infarcted heart by directly preserving the contractile capacity of the myocardium, inhibiting apoptosis of cardiomyocytes, and inducing therapeutic angiogenesis of the infarcted heart.

Nicaraven, a chemically synthesized hydroxyl radical-specific scavenger, has been demonstrated to protect against ischemia-reperfusion injury in various organs. We investigated whether nicaraven can attenuate radiation-induced injury in hematopoietic stem/progenitor cells, which is the conmen complication of radiotherapy and one of the major causes of death in sub-acute phase after accidental exposure to high dose radiation. C57BL/6 mice were exposed to 1 Gy γ-ray radiation daily for 5 days in succession (a total of 5 Gy), and given nicaraven or a placebo after each exposure. The mice were sacrificed 2 days after the last radiation treatment, and the protective effects and relevant mechanisms of nicaraven in hematopoietic stem/progenitor cells with radiation-induced damage were investigated by ex vivo examination. We found that post-radiation administration of nicaraven significantly increased the number, improved the colony-forming capacity, and decreased the DNA damage of hematopoietic stem/progenitor cells. The urinary levels of 8-oxo-2′-deoxyguanosine, a marker of DNA oxidation, were significantly lower in mice that were given nicaraven compared with those that received a placebo treatment, although the levels of intracellular and mitochondrial reactive oxygen species in the bone marrow cells did not differ significantly between the two groups. Interestingly, compared with the placebo treatment, the administration of nicaraven significantly decreased the levels of the inflammatory cytokines IL-6 and TNF-α in the plasma of mice. Our data suggest that nicaraven effectively diminished the effects of radiation-induced injury in hematopoietic stem/progenitor cells, which is likely associated with the anti-oxidative and anti-inflammatory properties of this compound. [ABSTRACT FROM AUTHOR]

Bone marrow stem cells from diabetes mellitus patients exhibit functional impairment, but the relative molecular mechanisms responsible for this impairment are poorly understood. We investigated the mechanisms responsible for diabetes-related functional impairment of bone marrow stem cells by extensively screening the expression levels of inflammatory factors, cell cycle regulating molecules, extracellular matrix molecules and adhesion molecules. Bone marrow cells were collected from type 2 diabetic (db/db) and healthy control (db/m+) mice, and c-kit+ stem cells were purified (purity>85%) for experiments. Compared with the healthy control mice, diabetic mice had significantly fewer c-kit+ stem cells, and these cells had a lower potency of endothelial differentiation; however, the production of the angiogenic growth factor VEGF did not differ between groups. A pathway-focused array showed that the c-kit+ stem cells from diabetic mice had up-regulated expression levels of many inflammatory factors, including Tlr4, Cxcl9, Il9, Tgfb1, Il4, and Tnfsf5, but no obvious change in the expression levels of cell cycle molecules. Interestingly, diabetes-related alterations of the extracellular matrix and adhesion molecules were varied; Pecam, Mmp10, Lamc1, Itgb7, Mmp9, and Timp4 were up-regulated, but Col11a1, Fn1, Admts2, and Itgav were down-regulated. Some of these changes were also confirmed at the protein level by flow cytometry analysis. In conclusion, c-kit+ bone marrow stem cells from diabetic mice exhibited an extensive enhancement of inflammatory factors and disorders of the extracellular matrix and adhesion molecules. Further intervention studies are required to determine the precise role of each molecule in the diabetes-related functional impairment of c-kit+ bone marrow stem cells. [ABSTRACT FROM AUTHOR]

: BackgroundLocal bone marrow cell implantation can induce angiogenesis. In the present study we investigated whether angiogenesis induced by bone marrow cell implantation improves deteriorated cardiac function in a rat heart model of hypoperfusion.: MethodsA hypoperfusion heart model was created in Dark Agouti rats by ligating the left anterior descending artery placed against a copper wire (φ275 μm), then pulling out the wire immediately. The left ventricular (LV) anterior wall was injected directly at six points, each with 1 × 107 bone marrow cells in 10 μL of phosphate-buffered saline or with phosphate-buffered saline only, respectively. Echocardiography was performed to evaluate the cardiac function 7, 30, 60, and 90 days after treatment. Microvessel density and blood flow in the LV anterior wall were estimated 60 days after treatment.: ResultsBoth the increase of LV end-systolic diameter and the decrease of percent of fractional shortening caused by myocardial ischemia were attenuated effectively by bone marrow cell implantation treatment. Bone marrow cell implantation treatment also increased the levels of angiopoietin-1 and vascular endothelial growth factor in the LV anterior wall. The microvessel density, blood flow, and thickness of the LV anterior wall significantly also increased after bone marrow cell implantation treatment compared with those after phosphate-buffered saline injection.: ConclusionsThe local implantation of autologous bone marrow cells induced angiogenesis and improved the perfusion of ischemic myocardium, thereby preventing LV remodeling and improving deteriorated cardiac function caused by myocardial hypoperfusion. [Copyright &y& Elsevier]

Presents information on a study that performed local implantation of autologous bone marrow cells to induce therapeutic angiogenesis for patients with ischemic heart or limb disease. Methodology of the study; Results and discussion on the study.

Background. Therapeutic angiogenesis was induced by local autologous bone marrow cell implantation (BMCI) in ischemic hindlimb or ischemic heart models in rats. This study was designed to investigate the toxicity and therapeutic potency of local BMCI using a chronic coronary occlusion model in dogs.Methods. The canine chronic coronary occlusion model was created by ligating of the left anterior descending artery (LAD). The myocardium in the left ventricle was divided into distinct normal, marginal, and infarction areas 30 days after LAD ligation. Each area was injected at two locations, with either 2 × 107 bone marrow cells (n = 7, BMCI group) or 0.1 mL phosphate-buffered saline (PBS) only (n = 7, PBS group), respectively. Hemodynamics were evaluated by a single ultrasonic transducer and echocardiography before and 30 days after the treatment. Angiogenesis was evaluated by vessel count 30 days after the treatment. The toxicity of BMCI treatment was also evaluated in 8 normal dogs by following changes in electrocardiography (ECG), echocardiography, local histology, and systemic biochemistry indexes.Results. There was a significantly higher percentage of wall thickening in the marginal area in the BMCI group than in the PBS group 30 days after treatment (14.5 ± 2.28 versus 8.1 ± 3.00, p = 0.002). Significantly more microvessels were observed in the marginal area in the BMCI group than in the PBS group 30 days after treatment (127.7 ± 20.1 versus 88.0 ± 10.2/field, p = 0.0007). No systemic or local toxicity was found following BMCI treatment in the acute or chronic phases.Conclusions. BMCI treatment improved local wall thickening dynamics, presumably due to the angiogenesis induced by the treatment. This indicates that it might be a safe and effective therapy for ischemic heart disease. [Copyright &y& Elsevier]