Injection Of Bone Marrow-derived Mononuclear Cells Research Articles

Major cardiovascular events after bone marrow mononuclear cell transplantation following acute myocardial infarction: an updated post-BAMI meta-analysis of randomized controlled trials

BackgroundThe effect of bone marrow-derived mononuclear cells (BM-MNCs) after acute myocardial infarction (AMI) on myocardial function indices such as left ventricular ejection fraction has been widely studied. However, the effect of this intervention on major adverse cardiovascular events (MACE) was not the principal purpose of most investigations and its role is unclear. The aim of this study was to investigate the possible long-term clinical efficacy of BM-MNCs on MACE after AMI.MethodsA comprehensive search was conducted through electronic databases for potentially eligible randomized trials investigating the impact of BM-MNC therapy following acute MI on clinical outcomes. Risk of bias of the eligible studies was assessed using the Cochrane Collaboration’s tool. The effect of treatment was displayed by risk ratio (RR) and its 95% confidence interval (CI) using random-effects model.ResultsInitial database searching found 1540 records and 23 clinical trials with a total of 2286 participants eligible for meta-analysis. Injection of BM-MNCs was associated with lower risk of composite end points of hospitalization for congestive heart failure (CHF), re-infarction, and cardiac-related mortality (91/1191 vs. 111/812, RR = 0.643, 95% CI = 0.489 to 0.845, p = 0.002). This effect was derived from both reduction of CHF (47/1220 vs. 62/841, RR = 0.568, 95% CI = 0.382 to 0.844, p = 0.005) and re-infarction rate (23/1159 vs. 30/775, RR = 0.583, 95% CI = 0.343 to 0.991, p = 0.046), but not cardiac-related mortality (28/1290 vs. 31/871, RR = 0.722, 95% CI = 0.436 to 1.197, p = 0.207).ConclusionThis is the first meta-analysis focused on the cardiovascular outcomes of stem cell therapy after AMI and it revealed that transplantation of BM-MNCs may reduce composite endpoint of hospitalization for CHF, re-infarction, and cardiac related mortality driven mainly by reducing reinfarction and hospitalization for heart failure rates but not cardiovascular mortality.

Intravenous transplantation of human muse cells improves blood perfusion in a mouse model of limb ischemia

Abstract Introduction Critical limb ischemia (CLI) is the end-stage of peripheral artery disease caused by atherosclerosis and inflammation. Despite advances in treatment of CLI, substantial number of patients with CLI suffer from severe pain, ulceration, and gangrene. Although the advent of stem cell-based therapy has opened a new avenue for the treatment of various diseases, accumulating evidence suggests current cell-based therapies are safe, but their efficacy is modest in CLI patients. Multilineage-differentiating stress enduring (Muse) cells were first reported by one of the authors and colleagues as endogenous pluripotent-like stem cells residing in the bone marrow, peripheral blood and connective tissue of many organs. Previous studies have demonstrated that systemic administration of exogenous Muse cells improves functional recovery after ischemic organ injury such as myocardial infarction. However, their therapeutic potential in CLI remains unclear. Objective The goal of this study is to elucidate the efficacy and safety of exogenous Muse cell transplantation with animal models of CLI. Methods Muse cells were isolated from human bone marrow-derived mesenchymal stem cells (MSCs) by fluorescence-activated cell sorting with anti-SSEA-3 antibody. To establish an animal model of CLI, 12–14-week-old male BALB/c mice were anesthetized and subjected to left femoral artery and vein resection. At 24 hours after establishment of hindlimb ischemia, mice were randomly divided into 5 groups and treated as follows: Group 1, intravenous injection of PBS as control group; group 2, intravenous injection of 3 × 104 SSEA3-negative MSCs (non-Muse MSCs); group 3, intravenous injection of 3 × 104 Muse cells; group 4, intramuscular injection of 3 × 104 Muse cells into ischemic limb; group 5, intramuscular injection of 2 × 105 mouse bone marrow-derived mononuclear cells (BM-MNCs) into ischemic limb (n=5 for each group). Hindlimb blood flow was evaluated by laser Doppler flowmetry for 14 days and expressed as the ratio of ischemic to non-ischemic hindlimb. Results We found that intramuscular injection of xenogeneic Muse cells without immunosuppression significantly improved the blood flow in the ischemic hindlimb compared to control at day 7 and 14 (0.67 vs. 0.52, p=0.0002 and 0.74 vs. 0.53, p<0.0001, respectively) similar to intramuscular injection of allogenic BM-MNCs. In addition, we also found that intravenous injection of xenogeneic Muse cells without immunosuppression significantly improved the blood flow in the ischemic hindlimb compared to control at day 7 and 14 (0.72, p<0.0001 and 0.67, p=0.004, respectively). In contrast, intravenous injection of xenogeneic non-Muse MSCs did not improve blood flow in the ischemic hindlimb. Conclusion Our result suggests that Muse cell-based regenerative therapy could be a novel, less invasive, cost-effective, and subsequently more effective treatment for CLI patients. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Grant-in-Aid for Scientific Research (KAKENHI)

Randomised, double-blind, placebo-controlled clinical trial for evaluating the efficacy of intracoronary injection of autologous bone marrow mononuclear cells in the improvement of the ventricular function in patients with idiopathic dilated myocardiopathy: a study protocol

BackgroundCellular therapies have been increasingly applied to diverse human diseases. Intracoronary infusion of bone marrow-derived mononuclear cells (BMMNC) has demonstrated to improve ventricular function after acute myocardial infarction. However, less information is available about the role of BMMNC therapy for the treatment of dilated myocardiopathies (DCs) of non-ischemic origin. This article presents the methodological description of a study aimed at investigating the efficacy of intracoronary injection of autologous BMMNCs in the improvement of the ventricular function of patients with DC.MethodsThis randomised, placebo-controlled, double-blinded phase IIb clinical trial compares the improvement on ventricular function (measured by the changes on the ejection fraction) of patients receiving the conventional treatment for DC in combination with a single dose of an intracoronary infusion of BMMNCs, with the functional recovery of patients receiving placebo plus conventional treatment. Patients assigned to both treatment groups are monitored for 24 months. This clinical trial is powered enough to detect a change in Left Ventricular Ejection Fraction (LVEF) equal to or greater than 9%, although an interim analysis is planned to re-calculate sample size.DiscussionThe study protocol was approved by the Andalusian Coordinating Ethics Committee for Biomedical Research (Comité Coordinador de Ética en Investigación Biomédica de Andalucia), the Spanish Medicines and Medical Devices Agency (Agencia Española de Medicamentos y Productos Sanitarios), and is registered at the EU Clinical Trials Register (EudraCT: 2013–002015-98). The publication of the trial results in scientific journals will be performed in accordance with the applicable regulations and guidelines to clinical trials.Trial registrationClinicalTrials.gov Identifier NCT02033278 (First Posted January 10, 2014): https://clinicaltrials.gov/ct2/show/NCT02033278; EudraCT number: 2013–002015-98, EU CT Register: https://www.clinicaltrialsregister.eu/ctr-search/search?query=2013-002015-98. Trial results will also be published according to the CONSORT statement at conferences and reported peer-reviewed journals.

Bone Marrow Cells Transplant in Septic Mice Modulates Systemic Inflammatory Response via Cell-Cell Contact.

Sepsis is a dynamic disease, displaying an inflammatory profile that varies over time and for each organ. Controlling the inflammatory response based in targeting a single molecule has been proved useless. We hypothesized that treatment with bone marrow-derived mononuclear cells (BMDMCs) may be more efficient to modulate the systemic inflammatory response to infection. Adult male Balb/c mice were subjected to cecal ligation and puncture (CLP) or endotoxemia model of experimental sepsis. BMDMCs were separated under Ficoll gradient and injected intravenously 1 h after the procedures. Cytokines concentration was quantified in plasma, lungs, heart, and gut. Spleens, lymph nodes, and thymus were used for lymphocytes isolation and cell death assessment. All measurements were performed 2 h after BMDMCs injection. RAW264.7 macrophages and BMDMCs were cocultivated in vitro to investigate the mechanisms involved. Our data showed that an early single intravenous injection of BMDMCs in animals submitted to the murine model of endotoxemia led to the improvement of survival rate; BMDMCs persistency in lung, liver, and spleen after 24 h; decreased necrosis and apoptosis of mononuclear cells; lower TNF-α, but increased IL-10 concentration in plasma; and tissue-specific cytokine profile. In vitro experiments demonstrated that IL-6, IL-10, and nitric oxide production depends on direct contact of BMDMCs to macrophages and that TNF-α production is negatively regulated by PGE2. BMDMCs are efficient in protecting animals from endotoxemia and sepsis, reducing systemic inflammation as well as specifically modulating tissue inflammation, producing the necessary immune regulation to re-equilibrate the inflammatory response.

Administration of Bone Marrow-Derived Mononuclear Cells Contributed to the Reduction of Hypoxic-Ischemic Brain Injury in Neonatal Rats.

Background/Objective: Perinatal hypoxic-ischemia (HI) causes neonatal death and permanent neurological deficits. Cell therapy using various cell sources has been recently identified as a novel therapy for perinatal HI. Among the available types of cell sources, bone marrow-derived mononuclear cells (BMMNCs) have unique features for clinical application. For example, stem cells can be collected after admission, thus enabling us to perform autologous transplantation. This study aimed to investigate whether the administration of BMMNCs ameliorated HI brain injury in a neonatal rat model.Methods: Seven-day-old rats underwent left carotid artery ligation and were exposed to 8% oxygen for 60 min. BMMNCs were collected from the femurs and tibias of juvenile rats using the Ficoll–Hypaque technique and injected intravenously 24 h after the insult (1 × 105 cells). Active caspase-3, as an apoptosis marker, and ED1, as an activated microglia/macrophage marker, were evaluated immunohistochemically 48 h after the insult (vehicle, n = 9; BMMNC, n = 10). Behavioral assessments using the rotarod treadmill, gait analysis, and active avoidance tests were initiated 3 weeks after the insult (sham, n = 9, vehicle, n = 8; BMMNC, n = 8). After these behavioral tests (6 weeks after the insult), we evaluated the volumes of their hippocampi, cortices, thalami, striata, and globus pallidus.Results: The mean cell densities of the sum of four parts that were positive for active caspase-3 significantly decreased in the BMMNC group (p < 0.05), whereas in the hippocampi, cortices, thalami, and striata cell densities decreased by 42, 60, 56, and 47%, respectively, although statistical significance was not attained. The number of ED1 positive cells for the sum of the four parts also significantly decreased in the BMMNC group compared to the vehicle group (p < 0.05), whereas in each of the four parts the decrease was 35, 39, 47, and 36%, respectively, although statistical significance was not attained. In gait analysis, the BMMNC normalized the contact area of the affected hind paw widened by HI. The volumes of the affected striata and globus pallidus were significantly larger in the BMMNC group than in the control group.Conclusion: These results indicated that the injection of BMMNCs ameliorated HI brain injury in a neonatal rat model.

The effects of a functionally-graded scaffold and bone marrow-derived mononuclear cells on steroid-induced femoral head osteonecrosis

Osteonecrosis of the femoral head (ONFH) is a debilitating disease that may progress to femoral head collapse and subsequently, degenerative arthritis. Although injection of bone marrow-derived mononuclear cells (BMMCs) is often performed with core decompression (CD) in the early stage of ONFH, these treatments are not always effective in prevention of disease progression and femoral head collapse. We previously described a novel 3D printed, customized functionally-graded scaffold (FGS) that improved bone growth in the femoral head after CD in a normal healthy rabbit, by providing structural and mechanical guidance. The present study demonstrates similar results of the FGS in a rabbit steroid-induced osteonecrosis model. Furthermore, the injection of BMMCs into the CD decreased the osteonecrotic area in the femoral head. Thus, the combination of FGS and BMMC provides a new therapy modality that may improve the outcome of CD for early stage of ONFH by providing both enhanced biological and biomechanical cues to promote bone regeneration in the osteonecrotic area.

New Modalities in Knee Osteoarthritis Treatment Using Autologous Bone Marrow-Derived Mononuclear Cells

Abstract The clinical effects on knee osteoarthritis (OA) symptoms and tissue structure were evaluated after bone marrow-derived mononuclear cell intraarticular injection. A group of 32 patients with 34 knee joints in stage II–III osteoarthritis were treated by intraarticular injection of mononuclear cell suspension. Clinical results were obtained by KOOS (Knee Osteoarthritis Outcome Score) and KSS (Knee Society Score) scores during a 12 months follow-up period. Radiological evaluation was performed using magnetic resonance imaging. A comparison with a control group of 28 patients treated with routinely used three hyaluronic acid intra-articular injections was made. No adverse effects were observed after the bone marrow derived mononuclear cells (BM-MNC) injection. At the end point of the follow up all score results had improved, compared to those at to the starting point. 65% of patients maintained minimal perceptible clinical improvement of the score results. The Whole Organ Magnetic Resonance Imaging Score showed improvement from 44.31 to 42.93 points (p &lt; 0.05) during a 6–7 month period. Comparing score results to the control group, a statistically significant (p &lt; 0.05) improvement in the KOOS pain subscale score at the 6 and 12 months was observed in the mononuclear cell group. BM-MNC injection leads to a decrease of knee OA symptoms and slows changes in structure of the degenerative joint tissue.

New Modalities in Knee Osteoarthritis Treatment Using Autologous Bone Marrow-Derived Mononuclear Cells

Abstract The clinical effects on knee osteoarthritis (OA) symptoms and tissue structure were evaluated after bone marrow-derived mononuclear cell intraarticular injection. A group of 32 patients with 34 knee joints in stage II–III osteoarthritis were treated by intraarticular injection of mononuclear cell suspension. Clinical results were obtained by KOOS (Knee Osteoarthritis Outcome Score) and KSS (Knee Society Score) scores during a 12 months follow-up period. Radiological evaluation was performed using magnetic resonance imaging. A comparison with a control group of 28 patients treated with routinely used three hyaluronic acid intra-articular injections was made. No adverse effects were observed after the bone marrow derived mononuclear cells (BM-MNC) injection. At the end point of the follow up all score results had improved, compared to those at to the starting point. 65% of patients maintained minimal perceptible clinical improvement of the score results. The Whole Organ Magnetic Resonance Imaging Score showed improvement from 44.31 to 42.93 points (p &lt; 0.05) during a 6–7 month period. Comparing score results to the control group, a statistically significant (p &lt; 0.05) improvement in the KOOS pain subscale score at the 6 and 12 months was observed in the mononuclear cell group. BM-MNC injection leads to a decrease of knee OA symptoms and slows changes in structure of the degenerative joint tissue.

Transplantation of hematopoietic stem cells: intra-arterial versus intravenous administration impacts stroke outcomes in a murine model

Based on results of hematopoietic stem cell transplantation in animal models of stroke, clinical trials with hematopoietic stem cells administered intra-arterially or intravenously have been initiated in patients. Although intra-arterial injection is expected to deliver transplanted cells more directly to the ischemic tissue, the optimal route for enhancing clinical outcomes has not been identified in the setting of stroke. In this study, we compared the therapeutic potential of intra-arterial versus intravenous injection of bone marrow derived-mononuclear cells (BM-MNCs) and CD133-positive (CD133(+)) cells in a murine stroke model. We have found that intra-arterial injection of BM-MNCs exaggerates inflammation with accompanying loss of microvascular structures in poststroke brain and no improvement in cortical function. In contrast, intravenous injection of BM-MNCs did not similarly enhance inflammation and improved cortical function. Our results indicate that the optimal route of cell transplantation can vary with different cell populations and highlight possible issues that might arise with intra-arterial cell administration for acute ischemic cerebrovascular disease.

Abstract 18016: Cell and Hydrogel-based Therapies Employing Cathelicidin Related Antimicrobial Peptide (CRAMP) Attenuate Cardiac Dysfunction in a Mouse Model of Myocardial Infarction: Potential Therapeutic Targets in Ischemic Heart Disease

Introduction: Limited stem cell retention following intracoronary administration has reduced the clinical efficacy of this novel therapy. Cathelicidins related antimicrobial proteins (CRAMPs) have been shown to prime bone marrow Derived mononuclear Cells (BMMNC) migration towards low gradients of SDF-1 suggesting a potential role in BMMNC retention. Here, we assessed the therapeutic efficacy of CRAMP in the context of BMMNC recruitment and retention via intracardiac delivery of CRAMP-treated BMMNCs or CRAMP-packed hydrogels (HG) post-myocardial infarction (MI). Methods and Results: During the in vivo cell studies, mice were randomized into 3 groups: MI followed by injection of PBS, BMMNCs alone, and BMMNCs incubated with CRAMP. During the in vivo HG studies, BM GFP chimera mice were randomized into 4 groups: MI followed by injection of HG alone, HG + SDF-1, HG + SDF-1 + CRAMP, HG + CRAMP. Changes in infarct size and cardiac function between 5 days and 5 weeks after MI were assessed using cardiac MRI (CMR) and echocardiography respectively. Treatment of BMMNCs with CRAMP enhanced their migration towards low, yet physiological, levels of SDF-1 in vitro (Fig 1A). In vivo, BMMNC+CRAMP therapy was associated with significant increase in capillary density as compared to the BMMNC-alone and control groups (Fig 1B). Moreover, BMMNC+CRAMP administration led to improvement in cardiac function and reduction in infarct size as compared to other groups (Fig 1C-D). Similar to the BMMNCs+CRAMP cell therapy, HG + SDF-1 + CRAMP administration post-MI led to improvement of cardiac function and reduction in infarct size compared with other groups (Fig 1E-F). Conclusion: Cathelicidins enhance BMMNC retention and recruitment after intramyocardial administration post-MI resulting in improvements in heart physiology and recovery. Therapies employing these strategies may represent an attractive method for improving outcomes of regenerative therapies in human studies.

GW24-e1170 The effects and safety of autologous intracoronary Bone Marrow Mononuclear Cells transplantation in cardiomyopathy

ObjectivesTo invest the effects and safety of autologous bone marrow–derived mononuclear cells (BMMNCs) transplantation in dilated cardiomyopathy. We report the results of the randomised trial of BMMNCs therapy in 20...

Combined Delivery of Bone Marrow‐Derived Mononuclear Cells in Chronic Ischemic Heart Disease: Rationale and Study Design

Treatment with bone marrow-derived mononuclear cells (BM-MNC) may improve left ventricular (LV) function in patients with chronic ischemic heart disease (IHD). Delivery method of the cell product may be crucial for efficacy. We aimed to demonstrate that the combination of intramyocardial and intracoronary injection of BM-MNC is safe and improves LV function in patients with chronic IHD. After a safety/feasibility phase of 10 patients, 54 patients will be randomly assigned in a 1:1:1 pattern to 1 control and 2 BM-MNC treatment groups. The control group will be treated with state-of-the-art medical management. The treatment groups will receive either exclusively intramyocardial injection or a combination of intramyocardial and intracoronary injection of autologous BM-MNC. Left ventricular function as well as scar size, transmural extension, and regional wall-motion score will be assessed by cardiac magnetic resonance imaging studies at baseline and after 6 months. The primary endpoint is the change in global LV ejection fraction by cardiac magnetic resonance from 6 months to baseline. The results, it is hoped, will have important clinical impact and provide essential information to improve the design of future regenerative-medicine protocols in cardiology. As cell delivery may play an important role in chronic IHD, we aim to demonstrate feasibility and efficacy of a combined cell-delivery approach in patients with decreased LV function.

Percutaneous, transendocardial injection of bone marrow-derived mononuclear cells in heart failure patients following acute ST-elevation myocardial infarction: ALSTER-Stem Cell trial

Patients with symptomatic heart failure following acute ST-elevation myocardial infarction (STEMI) received transendocardial application of bone marrow-derived mononuclear cells (BMC) to improve left ventricular (LV) function and clinical outcome. Patients (n=12) with LV ejection fraction (EF) <45% and NYHA Class ≥II received NOGA-guided transendocardial injection of BMC into the infarction border zone 17.5±0.8 days following successful interventional revascularisation after STEMI. A matched control group (n=11) was generated from the source data of the previously published LIPSIAbciximab-STEMI trial. Primary and secondary endpoints were derived from comparisons of baseline vs. six-month follow-up cardiac magnetic resonance imaging (CMR) measurements and clinical assessments. Following cell therapy we observed a significant increase of EF (+7.9±1.5%, p=0.001) while the control group showed no change. This effect was driven by a reduction of LV end-systolic volume (ESV) by -27.5±6.5 ml (p=0.001); LV end-diastolic volume (EDV) and scar volu-me remained unchanged. A significant decrease of NYHA Class was found only in the cell therapy group (-0.75 vs. -0.18, p=0.04). Findings were also translated into enhancement of clinical assessments (rehospitalisation for decompensated heart failure, six-minute walk test, NT-proBNP levels). The data suggest transendocardial injection of BMC can be used safely in patients with sympto-matic heart failure following acute STEMI. These prospective, preliminary data of a well-characterised, small cohort suggest efficiency compared to routine treatment.

Injectable Hydrogel Helps Bone Marrow-Derived Mononuclear Cells Restore Infarcted Myocardium

Backgrounds: Experimental and clinical studies have suggested that cell implantation could improve cardiac function after myocardial infarction (MI). However, this technique was limited by decreased engraftment and survival of transplanted cells within the ischemic tissue. The present study was performed to investigate whether implantation of bone marrow-derived mononuclear cells (BMMNCs) encapsulated in hydrogel could increase cell engraftment and help to restore cardiac function of MI rabbits. Methods: MI was induced in rabbits by coronary artery ligation. One week later, cell culture medium, Dex-PCL-HEMA/PNIPAAm hydrogel, BMMNCs in medium or BMMNCs in hydrogel were injected into the infarcted area of the left ventricle (LV). Results: Increased cell engraftment was observed 48 h after injection when cells were encapsulated in hydrogel; 30 days after treatment, echocardiographic studies showed that injection of BMMNCs in hydrogel preserved LV ejection fraction and attenuated LV dilatation compared with other groups. Histological analysis indicated that injection of BMMNCs in hydrogel enhanced neovascular formation and prevented scar expansion compared with the other groups. Conclusion: Injection of hydrogel-encapsulated BMMNCs increased cell engraftment and improved LV function; this technique may serve as an effective approach to restore infarcted myocardium.

D023 CHOP-10 Deletion improves neovascularization and stem/progenitor cells pro-angiogenic potential in type I diabetic mice with hindlimb ischemia

Diabetes-induced reactive oxygen species overproduction impairs neovascularization. CHOP 10 is a novel developmentally regulated nuclear protein that emerges as critical transcriptional integrator among pathways regulating differentiation, proliferation and survival. Of interest, CHOP-10 has been shown to trigger oxidative stress-induced β cells apoptosis in the setting of diabetes. Here, we analyzed the role of CHOP-10 in postnatal neovascularization and bone-marrow-derived mononuclear cells (BMC) pro-angiogenic potential in type I diabetic mice with hindlimb ischemia. Ischemia was induced by right femoral artery ligation in C57/ Bl6 animals (WT, n = 8), diabetic C57/Bl6 animals (diab WT, n = 8, Streptozotocin 40 mg/kg) and diabetic CHOP-10-deficient animals (diab CHOP-10 KO, n = 8). Two days after ischemia, CHOP-10 mRNA and protein levels were increased by 7- (p < 0.001) and 4-fold (p < 0.01), respectively in ischemic muscle of WT diab compared to WT. Angiographic score, capillary density and foot perfusion were increased by 3.3- (p < 0.01), 1.8- (p < 0.001) and 2.2-fold (p < 0.001)in diab CHOP-10 KO compared to WT diab, 21 days after ischemia. This effect was associated with a reduction in the number of apoptotic cells and an increase in eNOS levels in diab CHOP- 10 KO compared to WT diab. We next analyzed the role of CHOP- 10 in post-natal vasculogenesis. Injection of BMC isolated from diab CHOP-10 KO in WT mice with hindlimb ischemia improved neovascularization by around 1.8-fold when compared to WT diab BMC (p < 0.05). BMC isolated from diab CHOP-10 KO mice showed an upregulation of eNOS protein levels and an increase in their ability to differentiate into cells with endothelial phenotype in vitro differentiation assay. Finally, treatment of cultured HUVEC with homocysteine increased CHOP-10 mRNA levels and repressed eNOS gene expression. Consistent with these results, eNOS protein expression was significantly upregulated in the CHOP-10 siRNA- transfected endothelial cells. Additionally, overexpression of CHOP-10 inhibited the basal transcriptional activation of the eNOS promoter as assessed by a reporter gene assay using a 3,500-bp fragment of the human eNOS gene. Our study unravels an important inhibitory role of CHOP-10 in the regulation of vessel formation in the setting of diabetes.

NADPH Oxidase-Derived Overproduction of Reactive Oxygen Species Impairs Postischemic Neovascularization in Mice with Type 1 Diabetes

We hypothesized that diabetes-induced oxidative stress may affect postischemic neovascularization. The response to unilateral femoral artery ligation was studied in wild-type or gp91(phox)-deficient control or type 1 diabetic mice or in animals treated with the anti-oxidant N-acetyl-l-cysteine (NAC) or with in vivo electrotransfer of a plasmid encoding dominant-negative Rac1 (50 microg) for 21 days. Postischemic neovascularization was reduced in diabetic mice in association with down-regulated vascular endothelial growth factor-A protein levels. In diabetic animals vascular endothelial growth factor levels and postischemic neovascularization were restored to nondiabetic levels by the scavenging of reactive oxygen species (ROS) by NAC administration or the inhibition of ROS generation by gp91(phox) deficiency or by administration of dominant-negative Rac1. Finally, diabetes reduced the ability of adherent bone marrow-derived mononuclear cells (BM-MNCs) to differentiate into endothelial progenitor cells. Treatment with NAC (3 mmol/L), apocynin (200 micromol/L), or the p38MAPK inhibitor LY333351 (10 micromol/L) up-regulated the number of endothelial progenitor cell colonies derived from diabetic BM-MNCs by 1.5-, 1.6-, and 1.5-fold, respectively (P < 0.05). In the ischemic hindlimb model, injection of diabetic BM-MNCs isolated from NAC-treated or gp91(phox)-deficient diabetic mice increased neovascularization by approximately 1.5-fold greater than untreated diabetic BM-MNCs (P < 0.05). Thus, inhibition of NADPH oxidase-derived ROS overproduction improves the angiogenic and vasculogenic processes and restores postischemic neovascularization in type 1 diabetic mice.

Hybrid Surgical Angiogenesis: Omentopexy Can Enhance Myocardial Angiogenesis Induced by Cell Therapy

The conditions at the injection site are important in cell transplantation for severe ischemic heart disease. The omentum is both a well-vascularized tissue and a source of angiogenic factors. We examined the effectiveness of autologous bone marrow-derived mononuclear cells (BM-MNCs) with or without omentopexy in a large animal model. Myocardial infarction was generated in the lateral wall by ligation of coronary artery branches in miniswine. Animals received BM-MNC injection with or without omentopexy. Controls received saline only. Three weeks after surgery, regional myocardial blood flow and contractility were measured, and density of arterioles was evaluated immunohistologically. Angiography and postmortem examinations were performed to determine collateral communication. Regional myocardial contractility was significantly improved by BM-MNC transplantation both with and without omentopexy (0.29 +/- 0.02 vs 0.11 +/- 0.03, p < 0.01, 0.30 +/- 0.02 vs 0.12 +/- 0.01, p < 0.01, respectively). Relative regional myocardial blood flow in the combined omentopexy group was significantly higher than the controls both at rest (1.05 +/- 0.11 vs 0.57 +/- 0.07, p < 0.01) and under stress (1.09 +/- 0.08 vs 0.40 +/- 0.10, p < 0.01). The number of arterioles (< 50 microm) in both groups were higher than the controls (88.1 +/- 5.00 vs 38.1 +/- 8.99, p < 0.01 and 109.2 +/- 9.91 vs 38.1 +/- 8.99, p < 0.01, respectively). The number of large arterioles (> 50 microm) in the combined omentopexy group was significantly higher than in both BM-MNC alone (26.9 +/- 2.4 vs 17.6 +/- 1.8, p = 0.011) and controls (26.9 +/- 2.4 vs 10.0 +/- 1.3, p < 0.01). Collateral communication between the omentum and myocardium was demonstrated by angiography and postmortem injection. The BM-MNC transplantation may attenuate cardiac contractile dysfunction, and omentopexy may enhance angiogenesis induced by BM-MNC transplantation.