Therapeutic Effects Of Stem Cells Research Articles

Extracellular fraction of adipose tissue as an innovative regenerative approach for vitiligo treatment

Vitiligo is a common, disfiguring autoimmune disease that negatively affects patients' self-esteem and quality of life. Current treatments are moderately effective in reversing disease and promoting melanocyte regeneration. Thus, therapeutic advanced strategies are emerging from regenerative medicine. It has recently emerged that adipose tissue secretome may be used as a cell-free therapy in skin regeneration since paracrine functions of adipose-derived stem cells alone are responsible for most of the therapeutic effect of stem cells in several animal disease models. In this study, we tested the effect of adipose tissue extracellular fraction (AT-Ex) isolated from lipoaspirates on dermal and epidermal vitiligo cells in vitro. Using this experimental model, we demonstrated that molecules secreted by adipose tissue ameliorate the capability to counteract oxidative stress by a physiological stimulation of intracellular antioxidant enzymes and positively impact on cell proliferation. Due to the presence of Wnt-secreted factors, AT-Ex treatment promotes glycogen synthase kinase 3β inactivation and consequently Wnt/β-catenin pathway activation. Collectively, our findings show that AT-Ex could be useful as a natural approach to improve treatment of vitiligo.

Therapeutic effects of stem cells from human exfoliated deciduous teeth on diabetic peripheral neuropathy

ObjectiveTo evaluate the therapeutic potential of stem cells from human exfoliated deciduous teeth (SHED) for diabetic peripheral neuropathy.MethodsThe biological characteristics of SHED were identified by flow cytometric study and evaluation of differentiation potential. Using high-fat feeding, diabetes was induced in GK rats, and SHED were transplanted into the caudal veins of these rats. Immunohistochemical analysis was used to compare the capillary to muscle fiber ratio and intra-epidermal nerve fiber density between SHED- and saline-treated diabetic rats. Further, the expressions of angiogenesis-related and neurotrophic factors were quantified by real-time PCR and western blot.ResultsSHED had a capacity of multiple differentiation and shared typical characteristics of mesenchymal stem cells. SHED transplantation relieved diabetic neuropathic pain, enabled functional recovery of the peripheral nerves, and increased the capillary to muscle fiber ratio and intra-epidermal nerve fiber density compared to the saline group and normal controls. Real-time PCR results showed that the expressions of CD31, vWF, bFGF, NGF, and NT-3 in the skeletal muscles were higher in the SHED group than in the saline groups. Western blot results indicated that the levels of the CD31 and NGF proteins were higher in the SHED transplantation group than the saline group.ConclusionSHED transplantation ameliorated diabetic peripheral neuropathy in diabetic GK rats. Thus, systemic application of SHED could be a novel strategy for the treatment of diabetic peripheral neuropathy.

Microvesicles from human adipose stem cells promote wound healing by optimizing cellular functions via AKT and ERK signaling pathways

BackgroundHuman adipose stem cells (ASCs) have emerged as a promising treatment paradigm for skin wounds. Recent works demonstrate that the therapeutic effect of stem cells is partially mediated by extracellular vesicles, which comprise exosomes and microvesicles. In this study, we investigate the regenerative effects of isolated microvesicles from ASCs and evaluate the mechanisms how ASC microvesicles promote wound healing.MethodsAdipose stem cell-derived microvesicles (ASC-MVs) were isolated by differential ultracentrifugation, stained by PKH26, and characterized by electron microscopy and dynamic light scattering (DLS). We examined ASC-MV effects on proliferation, migration, and angiogenesis of keratinocytes, fibroblasts, and endothelial cells both in vitro and in vivo. Next, we explored the underlying mechanisms by gene expression analysis and the activation levels of AKT and ERK signaling pathways in all three kinds of cells after ASC-MV stimulation. We then assessed the effect of ASC-MVs on collagen deposition, neovascularization, and re-epithelialization in an in vivo skin injury model.ResultsASC-MVs could be readily internalized by human umbilical vein endothelial cells (HUVECs), HaCAT, and fibroblasts and significantly promoted the proliferation, migration, and angiogenesis of these cells both in vitro and in vivo. The gene expression of proliferative markers (cyclin D1, cyclin D2, cyclin A1, cyclin A2) and growth factors (VEGFA, PDGFA, EGF, FGF2) was significantly upregulated after ASC-MV treatment. Importantly, ASC-MVs stimulated the activation of AKT and ERK signaling pathways in those cells. The local injection of ASC-MVs at wound sites significantly increased the re-epithelialization, collagen deposition, and neovascularization and led to accelerated wound closure.ConclusionsOur data suggest that ASC-MVs can stimulate HUVEC, HaCAT, and fibroblast functions. ASC-MV therapy significantly accelerates wound healing, and the benefits of ASC-MVs may due to the involvement of AKT and ERK signaling pathways. This illustrates the therapeutic potential of ASC-MVs which may become a novel treatment paradigm for cutaneous wound healing.

Role of caveolin-1 in epidermal stem cells during burn wound healing in rats

Local transplantation of stem cells has therapeutic effects on skin damage but cannot provide satisfactory wound healing. Studies on the mechanisms underlying the therapeutic effects of stem cells on skin wound healing will be needed. Hence, in the present study, we explored the role of Caveolin-1 in epidermal stem cells (EpiSCs) in the modulation of wound healing. We first isolated EpiSCs from mouse skin tissues and established stable EpiSCs with overexpression of Caveolin-1 using a lentiviral construct. We then evaluated the epidermal growth factor (EGF)-induced cell proliferation ability using cell counting Kit-8 (CCK-8) assay and assessed EpiSC pluripotency by examining Nanog mRNA levels in EpiSCs. Furthermore, we treated mice with skin burn injury using EpiSCs with overexpression of Caveolin-1. Histological examinations were conducted to evaluate re-epithelialization, wound scores, cell proliferation and capillary density in wounds. We found that overexpression of Caveolin-1 in EpiSCs promoted EGF-induced cell proliferation ability and increased wound closure in a mouse model of skin burn injury. Histological evaluation demonstrated that overexpression of Caveolin-1 in EpiSCs promoted re-epithelialization in wounds, enhanced cellularity, and increased vasculature, as well as increased wound scores. Taken together, our results suggested that Caveolin-1 expression in the EpiSCs play a critical role in the regulation of EpiSC proliferation ability and alteration of EpiSC proliferation ability may be an effective approach in promoting EpiSC-based therapy in skin wound healing.

Intrastriatal transplantation of stem cells from human exfoliated deciduous teeth reduces motor defects in Parkinsonian rats

BackgroundThis study explored the neural differentiation and therapeutic effects of stem cells from human exfoliated deciduous teeth (SHED) in a rat model of Parkinson's disease (PD). MethodsThe SHED were isolated from fresh dental pulp and were induced to differentiate to neurons and dopamine neurons by inhibiting similar mothers against dpp (SMAD) signaling with Noggin and increase conversion of dopamine neurons from SHED with CHIR99021, Sonic Hedgehog (SHH) and FGF8 in vitro. The neural-primed SHED were transplanted to the striatum of 6-hydroxydopamine (6-OHDA)–induced PD rats to evaluate their neural differentiation and functions in vivo. ResultsThese SHED were efficiently differentiated to neurons (62.7%) and dopamine neurons (42.3%) through a newly developed method. After transplantation, the neural-induced SHED significantly improved recovery of the motor deficits of the PD rats. The grafted SHED were differentiated into neurons (61%), including dopamine neurons (22.3%), and integrated into the host rat brain by forming synaptic connections. Patch clamp analysis showed that neurons derived from grafted SHED have the same membrane potential profile as dopamine neurons, indicating these cells are dopamine neuron-like cells. The potential molecular mechanism of SHED transplantation in alleviating motor deficits of the rats is likely to be mediated by neuronal replacement and immune-modulation as we detected the transplanted dopamine neurons and released immune cytokines from SHED. ConclusionUsing neural-primed SHED to treat PD showed significant restorations of motor deficits in 6-OHDA–induced rats. These observations provide further evidence that SHED can be used for cell-based therapy of PD.

Therapeutic effects of stem cells in rodent models of Huntington's disease: Review and electrophysiological findings.

The principal symptoms of Huntington's disease (HD), chorea, cognitive deficits, and psychiatric symptoms are associated with the massive loss of striatal and cortical projection neurons. As current drug therapies only partially alleviate symptoms, finding alternative treatments has become peremptory. Cell replacement using stem cells is a rapidly expanding field that offers such an alternative. In this review, we examine recent studies that use mesenchymal cells, as well as pluripotent, cell-derived products in animal models of HD. Additionally, we provide further electrophysiological characterization of a human neural stem cell line, ESI-017, which has already demonstrated disease-modifying properties in two mouse models of HD. Overall, the field of regenerative medicine represents a viable and promising avenue for the treatment of neurodegenerative disorders including HD.

The role of extracellular vesicles in biomineralisation: current perspective and application in regenerative medicine

Extracellular vesicles comprise a heterogenous population of exosomes and microvesicles that have critical roles in intercellular signalling and tissue development. These complex particles have been implicated as mediators of the therapeutic effects of stem cells via the transfer of an assorted cargo of proteins and nucleic acids, which can modulate inflammation and enhance endogenous regeneration in a range of tissues. In addition, extracellular vesicles have the capacity to be loaded with therapeutic molecules for targeted delivery of pharmaceuticals. The versatility, biostability and biocompatibility of extracellular vesicles make them appealing for regenerative medicine and may endow considerable advantages over single molecule approaches. Furthermore, since production can be optimised and assessed ex vivo, extracellular vesicles present a decreased risk of neoplastic transformation when compared with cell-based methods. To date, the contribution of vesicles to tissue development has perhaps been most comprehensively defined within hard tissues, such as endochondral bone, where they were first identified in 1969 and henceforth referred to as matrix vesicles. Within developing bone, vesicles function as vehicles for the delivery of pro-osteogenic factors and initiate early nucleational events necessary for matrix mineralisation. However, advancement in our understanding of the biogenesis and characterisation of matrix vesicles has occurred largely in parallel to associated developments in wider extracellular vesicle biology. As such, there is a requirement to align current understanding of matrix vesicle–mediated mineralisation within the context of an evolving literature surrounding exosomes and microvesicles. In this review, we present an overview of current progress and opinion surrounding the application of vesicles in regenerative medicine with a primary focus on their potential as an acellular approach for enhancing hard tissue regeneration. This is balanced with an assessment of areas where further development is required to maximise their application for regenerative medicine.

Stem cells: a promising candidate to treat neurological disorders.

Neurologic impairments are usually irreversible as a result of limited regeneration in the central nervous system. Therefore, based on the regenerative capacity of stem cells, transplantation therapies of various stem cells have been tested in basic research and preclinical trials, and some have shown great prospects. This manuscript overviews the cellular and molecular characteristics of embryonic stem cells, induced pluripotent stem cells, neural stem cells, retinal stem/progenitor cells, mesenchymal stem/stromal cells, and their derivatives in vivo and in vitro as sources for regenerative therapy. These cells have all been considered as candidates to treat several major neurological disorders and diseases, owing to their self-renewal capacity, multi-directional differentiation, neurotrophic properties, and immune modulation effects. We also review representative basic research and recent clinical trials using stem cells for neurodegenerative diseases, including Parkinson’s disease, Alzheimer’s disease, and age-related macular degeneration, as well as traumatic brain injury and glioblastoma. In spite of a few unsuccessful cases, risks of tumorigenicity, and ethical concerns, most results of animal experiments and clinical trials demonstrate efficacious therapeutic effects of stem cells in the treatment of nervous system disease. In summary, these emerging findings in regenerative medicine are likely to contribute to breakthroughs in the treatment of neurological disorders. Thus, stem cells are a promising candidate for the treatment of nervous system diseases.

The potential therapeutic effect of stem cells loaded on two different vehicles (amniotic membrane and platelet rich plasma gel) in experimentally induced corneal alkali burns in rats

Background: Corneal alkali burns are common ophthalmic emergencies which may lead to permanent visual impairment. In spite of great advances made in the treatment of these cases, the structural and functional restoration of corneal alkali burns remains challenging. Bone marrow-derived mesenchymal stem cells (BM-MSCs) have been demonstrated to enhance corneal healing. However the problem remains in finding a suitable vehicle to deliver BM-MSCs to the site of injury.Objectives: To evaluate the therapeutic potential of BM-MSCs loaded on two biological vehicles (amniotic membrane versus platelet-rich plasma gel) in corneal alkali burns.Materials & Methods: Fifty rats were randomly divided into five equal groups. Group I (control group), group II (corneal ulcer group) and group III (recovery group). Group IV rats with corneal ulcers were treated with amniotic membrane loaded with BM-MSCs while in the group V the rats with corneal ulcers were treated with platelet-rich plasma cells loaded with BM-MSCs. The corneal specimens were processed for the light microscope, transmission electron microscope examination, and RT qPCR assay for VEGF and iNOS.Results: Group II showed epithelial separation and denudation with disorganized stroma and disrupted Descemet’s membrane and endothelium. Group III showed residual epithelial separation and vacuolation with neovascularization of the disorganized stroma. Group IV showed thinning of corneal epithelium with inflammatory infiltration of the stroma. Group V corneas revealed restoration of corneal epithelial thickness, organized stroma and continuous Descemet’s membrane. Also, there was an upregulation of iNOS & VEGF gene expression in groups II and III which was downregulated in group IV and V.Conclusions: The combination of BM-MSCs with PRP gel was a promising treatment for corneal alkali burns and may be applicable for other types of corneal disorders.

The Development of Stem Cell-Based Treatment for Liver Failure.

Liver failure is a devastating clinical syndrome with a persistently mortality rate despite advanced care. Orthotopic liver transplantation protected patients from hepatic failure. Yet, limitations including postoperative complications, high costs, and shortages of donor organs defect its application. The development of stem cell therapy complements the deficiencies of liver transplantation, due to the inherent ability of stem cells to proliferate and differentiate. Understand the source of stem cells, as well as the advantages and disadvantages of stem cell therapy. Based on published papers, we discussed the cell sources and therapeutic effect of stem cells. We also summarized the pros and cons, as well as optimization of stem cell-based treatment. Finally outlook future prospects of stem cell therapy. Stem cells may be harvested from a variety of human tissues, and then used to promote the convalescence of hepatocellular function. The emergence of the co-cultured system, tissueengineered technology and genetic modfication has further enhanced the functionality of stem cells. However, the tumorigenicity, the low survival rate and the scarcity of long-term treatment effect are obstacles for the further development of stem cell therapy. In this review, we highlight current research findings and present the future prospects in the area of stem cell-based treatment for liver failure.

Systemic Administration of Exosomes Released from Mesenchymal Stromal Cells Attenuates Apoptosis, Inflammation, and Promotes Angiogenesis after Spinal Cord Injury in Rats

Spinal cord injury (SCI) is one of the most common devastating injuries, which causes permanent disabilities such as paralysis and loss of movement or sensation. The precise pathogenic mechanisms of the disease remain unclear, and, as of yet, there is no effective cure. Mesenchymal stem cells (MSCs) show promise as an effective therapy in the experimental models of SCI. MSCs secrete various factors that can modulate a hostile environment, which is called the paracrine effect. Among these paracrine molecules, exosome is considered to be the most valuable therapeutic factor. Thus, exosomes from MSCs (MSCs-exosomes) can be a potential candidate of therapeutic effects of stem cells. The present study was designed to investigate the effect of whether systemic administration of exosomes generated from MSCs can promote the function recovery on the rat model of SCI in vivo. In the present study, we observed that systemic administration of MSCs-exosomes significantly attenuated lesion size and improved functional recovery post-SCI. Additionally, MSCs-exosomes treatment attenuated cellular apoptosis and inflammation in the injured spinal cord. Expression levels of proapoptotic protein (Bcl-2-associated X protein) and proinflammatory cytokines (tumor necrosis factor alpha and interleukin [IL]-1β) were significantly decreased after MSCs-exosomes treatment, whereas expression levels of antiapoptotic (B-cell lymphoma 2) and anti-inflammatory (IL-10) proteins were upregulated. Further, administration of MSCs-exosomes significantly promoted angiogenesis. These results show, for the first time, that systemic administration of MSCs-exosomes attenuated cell apoptosis and inflammation, promoted angiogenesis, and promoted functional recovery post-SCI, suggesting that MSCs-exosomes hold promise as a novel therapeutic strategy for treating SCI.

Stem Cell-Induced Biobridges as Possible Tools to Aid Neuroreconstruction after CNS Injury.

Notch-induced mesenchymal stromal cells (MSCs) mediate a distinct mechanism of repair after brain injury by forming a biobridge that facilitates biodistribution of host cells from a neurogenic niche to the area of injury. We have observed the biobridge in an area between the subventricular zone and the injured cortex using immunohistochemistry and laser capture. Cells in the biobridge express high levels of extracellular matrix metalloproteinases (MMPs), specifically MMP-9, which co-localized with a trail of MSCs graft. The transplanted stem cells then become almost undetectable, being replaced by newly recruited host cells. This stem cell-paved biobridge provides support for distal migration of host cells from the subventricular zone to the site of injury. Biobridge formation by transplanted stem cells seems to have a fundamental role in initiating endogenous repair processes. Two major stem cell-mediated repair mechanisms have been proposed thus far: direct cell replacement by transplanted grafts and bystander effects through the secretion of trophic factors including fibroblast growth factor 2 (FGF-2), epidermal growth factor (EGF), stem cell factor (SCF), erythropoietin, and brain-derived neurotrophic factor (BDNF) among others. This groundbreaking observation of biobridge formation by transplanted stem cells represents a novel mechanism for stem cell mediated brain repair. Future studies on graft-host interaction will likely establish biobridge formation as a fundamental mechanism underlying therapeutic effects of stem cells and contribute to the scientific pursuit of developing safe and efficient therapies not only for traumatic brain injury but also for other neurological disorders. The aim of this review is to hypothetically extend concepts related to the formation of biobridges in other central nervous system disorders.

MicroRNA-Mediated Down-Regulation of Apoptosis Signal-Regulating Kinase 1 (ASK1) Attenuates the Apoptosis of Human Mesenchymal Stem Cells (MSCs) Transplanted into Infarcted Heart.

Stem cell therapy using adult stem cells, such as mesenchymal stem cells (MSCs) has produced some promising results in treating the damaged heart. However, the low survival rate of MSCs after transplantation is still one of the crucial factors that limit the therapeutic effect of stem cells. In the damaged heart, oxidative stress due to reactive oxygen species (ROS) production can cause the death of transplanted MSCs. Apoptosis signal-regulating kinase 1 (ASK1) has been implicated in the development of oxidative stress-related pathologic conditions. Thus, we hypothesized that down-regulation of ASK1 in human MSCs (hMSCs) might attenuate the post-transplantation death of MSCs. To test this hypothesis, we screened microRNAs (miRNAs) based on a miRNA-target prediction database and empirical data and investigated the anti-apoptotic effect of selected miRNAs on human adipose-derived stem cells (hASCs) and on rat myocardial infarction (MI) models. Our data indicated that miRNA-301a most significantly suppressed ASK1 expression in hASCs. Apoptosis-related genes were significantly down-regulated in miRNA-301a-enriched hASCs exposed to hypoxic conditions. Taken together, these data show that miRNA-mediated down-regulation of ASK1 protects MSCs during post-transplantation, leading to an increase in the efficacy of MSC-based cell therapy.

Therapeutic effects of stem cells on ischemic stroke were confirmed in an improved photothrombotic mouse model.

See accompanying article by Yun-Kyong Choi et al. DOI 10.1002/biot.201600057 Photothrombosis models with well-defined infarcts in specific regions of the cortex were developed by adjusting the intensity, duration and field of light/laser of irradiation. Infarct sizes, cellular and motor behaviors were observed. Optimal operation parameters were determined to create suitable lesions that mimic stroke. The model was used in the study of bone marrow-derived mesenchymal stem cells transplantation therapy. Neurogenesis and behavior recovery were observed after transplantation. Ischemic stroke is becoming a major cause of serious brain damage with enormous cost to the society in aftercare 1 and the loss of productivity in developed countries. Effective animal models for ischemic stroke are very important to improve our understanding to the pathophysiologic mechanism, treatment and prognosis of this complicated disease. However, the actual applicability of the animal study data on human treatment of various aspects of stroke-related symptoms is not all satisfactory. For example, the most common technique 2 used to induce ischemic stroke, middle cerebral artery occlusion (MCAO) produces significant edema and size variability which bring forth uncertainty in the interpretation of the observed behavior. The photothrombotic ischemia model 3, on the other hand, is more reproducible and reliable due to its much milder damages to the brain. Furthermore, as shown in Fig. 1, well-defined infarcts can be made to have more precise volume and location, with optimized operation parameters such as irradiation intensity, field and duration. In the current paper 4, a study to improve the method by determining better operation parameters for the photothrombotic method was conducted. The usefulness of a particular model for scientific studies resides closely with how much the model resembles human conditions, at molecular, cellular, physiological and systemic levels, of the studied disease or symptoms. Cerebral vasculature is one of the most important factors that affect the selection of proper models for specific stroke study. The ability to observe partial or complete recovery in brain tissue or motor function of a particular model is also important for developing treatment. In those areas, the well-controlled photothrombotic model presents a good opportunity for the medical research community. Laser is used to create thrombotic clots in specific regions of the brain, in order to produce well-controlled mimics of ischemic stroke in animal models. The authors present their results of stem-cell therapy 5 based on this model, as an example of the applicability of their improved method. In their results of transplantation of bone marrow-derived mesenchymal stem cells, significant improvement in neurogenesis with high reliability was reported. A stable animal model by the current method will benefit future researchers in ischemic brain diseases. The author declares no financial or commercial conflict of interest.

Therapeutic effects of adipose-derived stem cells pretreated with pioglitazone in an emphysema mouse model.

There is no therapy currently available that influences the natural history of disease progression in patients with chronic obstructive pulmonary disease (COPD). Although stem cell therapy is considered a potential therapeutic option in COPD, there are no clinical trials proving definitive therapeutic effects in patients with COPD. Recently, it was reported that pioglitazone might potentiate the therapeutic effects of stem cells in patients with heart or liver disease. To test the capacity of pioglitazone pretreatment of stem cells for emphysema repair, we evaluated the therapeutic effects of pioglitazone-pretreated human adipose-derived mesenchymal stem cells (ASCs) on elastase-induced or cigarette smoke-induced emphysema in mice. We also investigated the mechanisms of action of pioglitazone-pretreated ASCs. Pioglitazone-pretreated ASCs had a more potent therapeutic effect than non-pretreated ASCs in the repair of both elastase-induced and smoke-induced emphysema models (mean linear intercept, 78.1±2.5 μm vs 83.2±2.6 μm in elastase models and 75.6±1.4 μm vs 80.5±3.2 μm in smoke models, P<0.05). Furthermore, we showed that pioglitazone-pretreated ASCs increased vascular endothelial growth factor (VEGF) production both in vitro and in mouse lungs in the smoke-induced emphysema model. Pioglitazone-pretreated ASCs may have more potent therapeutic effects than non-pretreated ASCs in emphysema mouse models.

Adipose-derived stem cell exosomes alleviate pathology of amyotrophic lateral sclerosis in vitro

Amyotrophic lateral sclerosis (ALS) is a degenerative disorder that involves the death of motor neurons in the cortex, brain stem, and spinal cord. Adipose-derived stem cells (ADSCs) are considered as a perspective remedy for therapy of neurodegenerative diseases including ALS. Stem cells secrete various factors which can modulate a hostile environment, called paracrine effect. Exosomes are small extracellular vesicles containing cell derived factors and mediate paracrine effect of cells. Thus, exosomes from ADSCs (ADSC-exo) can be a potential candidate of therapeutic effects of stem cells. To investigate the effect of ADSC-exo on the cellular phenotypes of ALS, we used neuronal stem cells (NSCs), which can be differentiated into neuronal cells, isolated from wild type or G93A ALS mice model. ADSC-exo was treated to neuronal cells from G93A ALS mice model. Immunocytochemistry and dot-blot assay result showed that ADSC-exo alleviated aggregation of superoxide dismutase 1 (SOD1). Reduction of cytosolic SOD1 level by ADSC-exo was also confirmed by western blot. Mitochondria display various abnormalities in ALS and the decrease of phospho-CREB and PGC-1α were observed in the G93A cells. ADSC-exo treatment showed normalization of phospho-CREB/CREB ratio and PGC-1α expression level. Our results suggest that ADSC-exo modulates cellular phenotypes of ALS including SOD-1 aggregation and mitochondrial dysfunction, and can be a therapeutic candidate for ALS.

DTI metrics can be used as biomarkers to determine the therapeutic effect of stem cells in acute peripheral nerve injury.

To determine the role of diffusion tensor imaging (DTI) metrics as biomarkers for the therapeutic effects of mesenchymal stem cells (MSCs) in acute peripheral nerve injury. Forty-four adult rats received subepineurial microinjection of MSCs (n = 22) or phosphate buffered saline (PBS, n = 22) 1 week after the sciatic nerve trunk crush injury. Sequential fat-suppressed T2-weighted imaging, T2 measurement, DTI and sciatic nerve functional assessment were performed at a 3.0 Tesla MR unit over an 8-week follow-up, with histological assessments performed at regular intervals. The sciatic nerve function index, T2 value, and DTI metrics, including fractional anisotropy (FA), axial diffusivity, radial diffusivity (RD), and mean diffusivity values of the distal stumps of crushed nerves were measured and compared between the two groups. Nerves treated with MSCs showed better functional recovery and exhibited more pronounced nerve regeneration compared with nerves treated with PBS. T2 values in nerves treated with MSCs or PBS showed a similar change pattern (P = 0.174), while FA and RD values in nerves treated with MSCs showed more rapid return (one week earlier) to baseline level than nerves treated with PBS (P = 0.045; 0.035). Nerves treated with MSCs had higher FA and lower RD values than nerves treated with PBS during the period from 2 to 3 weeks after surgery (P ≤ 0.0001, 0.004; P = 0.004, 0.006). FA and RD values derived from DTI might be used as sensitive biomarkers for detecting the therapeutic effect of stem cells in acute peripheral nerve crush injuries. 2 J. Magn. Reson. Imaging 2017;45:855-862.

Abstract 40: Interleukin-10 Deficiency Impairs Reparative Properties of Bone Marrow-derived Endothelial Progenitor Cell Exosomes Function in Ischemic Myocardium

Endothelial progenitor cell (EPC) based therapy promotes neovascularization in ischemic myocardium. Studies suggest that therapeutic effect of stem cells is largely due to paracrine mechanisms including stem cell-derived exosomes that are emerging as key paracrine mediators of stem cell functions. However, the autologous transplantation of EPCs in patients with systemic inflammation, which is a common symptom in patients with ischemic heart diseases, yield modest results suggesting the compromised cell function and altered exosome performance. We hypothesized that EPCs under inflammatory stress secrete dysfunctional exosomes with altered contents including packaged microRNAs, which eventually compromises exosomes repair ability in ischemic myocardium. Whether modulation of identified targets like specific microRNAs in the cargo of exosomes can rescue and/or enhance their reparative properties of dysfunctional exosomes is not known. We have previously shown in Interleukin-10 (IL-10) KO mice (model mimicking systemic inflammation) that loss of IL-10 impairs EPCs functions via miR-375. After cell expansion, we isolated exosomes from these two groups and compared their functions in terms of cell survival, proliferation, migration and angiogenic capacity in vitro and in vivo . We report that WT-EPC-exosomes (Exo) transplantation in the ischemic myocardium after MI significantly improved post-infarct repair, neovascularization and left ventricle functions. Our in vitro studies revealed that WT-EPC-Exo treatment enhanced endothelial cells proliferation and tube formation and inhibited apoptosis; whereas IL-10 KO-EPC-Exo exhibited opposite effects, suggesting that reparative capacity of WT-EPC-Exo is lost in exosomes derived from IL-10 KO-EPCs. Exosome miRNA profiling revealed a drastically different expression patterns with enrichment of inflammation induced microRNAs including significantly higher expression of miR-375. Interestingly, Knockdown of miR-375 in IL-10-EPCs decreased the expression level of miR-375 in their exosomes and partly rescued their angiogenic dysfunctions. Taken together, our studies suggest that modulation of miR-375 in IL-10 KO-EPC-Exo can rescue its phenotype and promote cardiac repair.

Endometrial stem cells expansion capability for local and systemic routes of administration in a model of experimentally injured endometrium

Endometrial stem cells due to their therapeutic characteristics could to be an effective tool of cell technologies in reproductive medicine. The aim of the study was to determine the most therapeutically effective route of administration for endometrial stem cells suspension. The study was conducted in approved animal model of injured endometrium. To create the experimental model tissue pieces of autologous endometrium were implanted on the anterior abdominal wall peritoneum using general surgical techniques. Experimental group animals were treated with endometrial stem cells suspension; in the control animal group a placebo was used. Local and systemic routes of endometrial stem cells administration were compared. The direct injections of stem cells suspension in the endometrial implants were used as the local route of administration, the intravenous injections of stem cells suspension were used as a systemic route. Endometrial stem cells expansion didn’t depend on the routes of administration, whereas therapeutic effects of stem cells was more obvious in tissue pieces after local injection of stem cells.

Angio-Vasculogenic Properties of Endothelial-Induced Mesenchymal Stem Cells Derived From Human Adipose Tissue.

Although stem cells have been regarded as a promising therapeutic option, the marginal therapeutic effects of stem cells are limitations that must be overcome for the development of effective cell therapy. This study sought to identify the angio-vasculogenic properties of endothelial differentiated mesenchymal stem cells (MSCs) and to determine whether these cells are effective for vascular repair. Adipose MSCs were cultured for 10 days under endothelial cell (EC) culture conditions. These endothelial cell differentiated adipose MSCs (EA) and undifferentiated adipose MSCs (UA) were characterized via angiogenesis and adhesion assays. These cells were transplanted into a hindlimb ischemia (HLI) model to determine therapeutic effects and their underlying mechanisms. EA displayed low adhesion and angiogenic properties in vitro compared with UA. When implanted into mouse HLI models, EA exhibited the decreased recovery of blood perfusion in limb ischemia than uncultured UA. Histology data showed that injected EA exhibited lower retention, angiogenic cytokine levels, and neovascularization in vivo than did UA. Short-term differentiated EA display less cell engraftment and angio-vasculogenic potential, and are less effective for peripheral vascular repair than UA. EC differentiation of MSCs may not present an effective strategy for the promotion of therapeutic neovascularization.