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Li M, Li H, Ruan Y, Wang T, Liu J. Stem Cell Therapy for Diabetic Erectile Dysfunction in Rats: A Meta-Analysis. PLoS One 2016; 11:e0154341. [PMID: 27111659 PMCID: PMC4844188 DOI: 10.1371/journal.pone.0154341] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 04/11/2016] [Indexed: 01/23/2023] Open
Abstract
Introduction Stem cell therapy is a novel method for the treatment of diabetic erectile dysfunction (ED). Many relative animal studies have been done to evaluate the efficacy of this therapy in rats. Aims This meta-analysis was performed to compare the efficacy of different stem cell therapies, to evaluate the influential factors and to determine the optimal stem cell therapeutic strategy for diabetic ED. Methods We searched the studies analyzing the efficacy of stem cell therapy for diabetic ED in rats published before September 30, 2015 in PubMed, Web of Science and EBSCO. A random effects meta-analysis was conducted to assess the outcomes of stem cell therapy. Subgroup analysis was also performed by separating these studies based on their different characteristics. Changes in the ratio of intracavernous pressure (ICP) to mean arterial pressure (MAP) and in the structure of the cavernous body were compared. Results 10 studies with 302 rats were enrolled in this meta-analysis. Pooled analysis of these studies showed a beneficial effect of stem cell therapy in improving erectile function of diabetic rats (SMD 4.03, 95% CI = 3.22 to 4.84, P< 0.001). In the stem cell therapy group, both the smooth muscle and endothelium content were much more than those in control group. There was also significant increase in the expression of endothelial nitric oxide synthase (eNOS) and neuronal nitric oxide synthase (nNOS), the ratio of smooth muscle to collagen, as well as the secretion of vascular endothelial growth factor (VEGF). Besides, apoptotic cells were reduced by stem cell treatment. The subgroup analysis indicated that modified stem cells were more effective than those without modification. Conclusions Our results confirmed that stem cell therapy could apparently improve the erectile function of diabetic rats. Some specific modification, especially the gene modification with growth factors, could improve the efficacy of stem cell therapy. Stem cell therapy has potential to be an effective therapeutic strategy for diabetic ED.
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Affiliation(s)
- Mingchao Li
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Hao Li
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- * E-mail: (HL); (JL)
| | - Yajun Ruan
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Tao Wang
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Jihong Liu
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- * E-mail: (HL); (JL)
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Oxygen cycling to improve survival of stem cells for myocardial repair: A review. Life Sci 2016; 153:124-31. [PMID: 27091653 DOI: 10.1016/j.lfs.2016.04.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 03/28/2016] [Accepted: 04/08/2016] [Indexed: 02/08/2023]
Abstract
Heart disease represents the leading cause of death among Americans. There is currently no clinical treatment to regenerate viable myocardium following myocardial infarction, and patients may suffer progressive deterioration and decreased myocardial function from the effects of remodeling of the necrotic myocardium. New therapeutic strategies hold promise for patients who suffer from ischemic heart disease by directly addressing the restoration of functional myocardium following death of cardiomyocytes. Therapeutic stem cell transplantation has shown modest benefit in clinical human trials with decreased fibrosis and increased functional myocardium. Moreover, autologous transplantation holds the potential to implement these therapies while avoiding the immunomodulation concerns of heart transplantation. Despite these benefits, stem cell therapy has been characterized by poor survival and low engraftment of injected stem cells. The hypoxic tissue environment of the ischemic/infracting myocardium impedes stem cell survival and engraftment in myocardial tissue. Hypoxic preconditioning has been suggested as a viable strategy to increase hypoxic tolerance of stem cells. A number of in vivo and in vitro studies have demonstrated improved stem cell viability by altering stem cell secretion of protein signals and up-regulation of numerous paracrine signaling pathways that affect inflammatory, survival, and angiogenic signaling pathways. This review will discuss both the mechanisms of hypoxic preconditioning as well as the effects of hypoxic preconditioning in different cell and animal models, examining the pitfalls in current research and the next steps into potentially implementing this methodology in clinical research trials.
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Gilmour AD, Woolley AJ, Poole-Warren LA, Thomson CE, Green RA. A critical review of cell culture strategies for modelling intracortical brain implant material reactions. Biomaterials 2016; 91:23-43. [PMID: 26994876 DOI: 10.1016/j.biomaterials.2016.03.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 02/29/2016] [Accepted: 03/06/2016] [Indexed: 02/07/2023]
Abstract
The capacity to predict in vivo responses to medical devices in humans currently relies greatly on implantation in animal models. Researchers have been striving to develop in vitro techniques that can overcome the limitations associated with in vivo approaches. This review focuses on a critical analysis of the major in vitro strategies being utilized in laboratories around the world to improve understanding of the biological performance of intracortical, brain-implanted microdevices. Of particular interest to the current review are in vitro models for studying cell responses to penetrating intracortical devices and their materials, such as electrode arrays used for brain computer interface (BCI) and deep brain stimulation electrode probes implanted through the cortex. A background on the neural interface challenge is presented, followed by discussion of relevant in vitro culture strategies and their advantages and disadvantages. Future development of 2D culture models that exhibit developmental changes capable of mimicking normal, postnatal development will form the basis for more complex accurate predictive models in the future. Although not within the scope of this review, innovations in 3D scaffold technologies and microfluidic constructs will further improve the utility of in vitro approaches.
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Affiliation(s)
- A D Gilmour
- Graduate School of Biomedical Engineering, The University of New South Wales, Sydney, NSW 2052, Australia.
| | - A J Woolley
- Graduate School of Biomedical Engineering, The University of New South Wales, Sydney, NSW 2052, Australia; Western Sydney University, Sydney, NSW, Australia
| | - L A Poole-Warren
- Graduate School of Biomedical Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
| | - C E Thomson
- Department of Veterinary Medicine, University of Alaska, Fairbanks, AK 99775, USA
| | - R A Green
- Graduate School of Biomedical Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
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Stegen S, van Gastel N, Eelen G, Ghesquière B, D'Anna F, Thienpont B, Goveia J, Torrekens S, Van Looveren R, Luyten FP, Maxwell PH, Wielockx B, Lambrechts D, Fendt SM, Carmeliet P, Carmeliet G. HIF-1α Promotes Glutamine-Mediated Redox Homeostasis and Glycogen-Dependent Bioenergetics to Support Postimplantation Bone Cell Survival. Cell Metab 2016; 23:265-79. [PMID: 26863487 PMCID: PMC7611069 DOI: 10.1016/j.cmet.2016.01.002] [Citation(s) in RCA: 136] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 10/19/2015] [Accepted: 01/02/2016] [Indexed: 12/23/2022]
Abstract
Cell-based therapy is a promising strategy in regenerative medicine, but the poor survival rate of the implanted cells remains a major challenge and limits clinical translation. We preconditioned periosteal cells to the hypoxic and ischemic environment of the bone defect site by deleting prolyl hydroxylase domain-containing protein 2 (PHD2), resulting in hypoxia-inducible factor 1 alpha (HIF-1α) stabilization. This strategy increased postimplantation cell survival and improved bone regeneration. The enhanced cell viability was angiogenesis independent but relied on combined changes in glutamine and glycogen metabolism. HIF-1α stabilization stimulated glutaminase-mediated glutathione synthesis, maintaining redox homeostasis at baseline and during oxidative or nutrient stress. Simultaneously, HIF-1α signaling increased glycogen storage, preventing an energy deficit during nutrient or oxygen deprivation. Pharmacological inhibition of PHD2 recapitulated the adaptations in glutamine and glycogen metabolism and, consequently, the beneficial effects on cell survival. Thus, targeting cellular metabolism is an appealing strategy for bone regeneration and cell-based therapy in general.
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Affiliation(s)
- Steve Stegen
- Laboratory of Clinical and Experimental Endocrinology, Department of Clinical and Experimental Medicine, KU Leuven, 3000 Leuven, Belgium; Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, 3000 Leuven, Belgium
| | - Nick van Gastel
- Laboratory of Clinical and Experimental Endocrinology, Department of Clinical and Experimental Medicine, KU Leuven, 3000 Leuven, Belgium; Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, 3000 Leuven, Belgium
| | - Guy Eelen
- Laboratory of Angiogenesis & Vascular Metabolism, Vesalius Research Center, Department of Oncology, KU Leuven/VIB, 3000 Leuven, Belgium
| | - Bart Ghesquière
- Laboratory of Angiogenesis & Vascular Metabolism, Vesalius Research Center, Department of Oncology, KU Leuven/VIB, 3000 Leuven, Belgium
| | - Flora D'Anna
- Laboratory of Translational Genetics, Vesalius Research Center, Department of Oncology, KU Leuven/VIB, 3000 Leuven, Belgium
| | - Bernard Thienpont
- Laboratory of Translational Genetics, Vesalius Research Center, Department of Oncology, KU Leuven/VIB, 3000 Leuven, Belgium
| | - Jermaine Goveia
- Laboratory of Angiogenesis & Vascular Metabolism, Vesalius Research Center, Department of Oncology, KU Leuven/VIB, 3000 Leuven, Belgium
| | - Sophie Torrekens
- Laboratory of Clinical and Experimental Endocrinology, Department of Clinical and Experimental Medicine, KU Leuven, 3000 Leuven, Belgium
| | - Riet Van Looveren
- Laboratory of Clinical and Experimental Endocrinology, Department of Clinical and Experimental Medicine, KU Leuven, 3000 Leuven, Belgium
| | - Frank P Luyten
- Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, 3000 Leuven, Belgium; Skeletal Biology and Engineering Research Center, Department of Development and Regeneration, KU Leuven, 3000 Leuven, Belgium
| | - Patrick H Maxwell
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XU, UK
| | - Ben Wielockx
- Heisenberg Research Group, Department of Clinical Pathobiochemistry, Institute for Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, 01069 Dresden, Germany
| | - Diether Lambrechts
- Laboratory of Translational Genetics, Vesalius Research Center, Department of Oncology, KU Leuven/VIB, 3000 Leuven, Belgium
| | - Sarah-Maria Fendt
- Laboratory of Cellular Metabolism and Metabolic Regulation, Vesalius Research Center, Department of Oncology, KU Leuven/VIB, 3000 Leuven, Belgium
| | - Peter Carmeliet
- Laboratory of Angiogenesis & Vascular Metabolism, Vesalius Research Center, Department of Oncology, KU Leuven/VIB, 3000 Leuven, Belgium
| | - Geert Carmeliet
- Laboratory of Clinical and Experimental Endocrinology, Department of Clinical and Experimental Medicine, KU Leuven, 3000 Leuven, Belgium; Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, 3000 Leuven, Belgium.
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McMurtrey RJ. Analytic Models of Oxygen and Nutrient Diffusion, Metabolism Dynamics, and Architecture Optimization in Three-Dimensional Tissue Constructs with Applications and Insights in Cerebral Organoids. Tissue Eng Part C Methods 2016; 22:221-49. [PMID: 26650970 PMCID: PMC5029285 DOI: 10.1089/ten.tec.2015.0375] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Diffusion models are important in tissue engineering as they enable an understanding of gas, nutrient, and signaling molecule delivery to cells in cell cultures and tissue constructs. As three-dimensional (3D) tissue constructs become larger, more intricate, and more clinically applicable, it will be essential to understand internal dynamics and signaling molecule concentrations throughout the tissue and whether cells are receiving appropriate nutrient delivery. Diffusion characteristics present a significant limitation in many engineered tissues, particularly for avascular tissues and for cells whose viability, differentiation, or function are affected by concentrations of oxygen and nutrients. This article seeks to provide novel analytic solutions for certain cases of steady-state and nonsteady-state diffusion and metabolism in basic 3D construct designs (planar, cylindrical, and spherical forms), solutions that would otherwise require mathematical approximations achieved through numerical methods. This model is applied to cerebral organoids, where it is shown that limitations in diffusion and organoid size can be partially overcome by localizing metabolically active cells to an outer layer in a sphere, a regionalization process that is known to occur through neuroglial precursor migration both in organoids and in early brain development. The given prototypical solutions include a review of metabolic information for many cell types and can be broadly applied to many forms of tissue constructs. This work enables researchers to model oxygen and nutrient delivery to cells, predict cell viability, study dynamics of mass transport in 3D tissue constructs, design constructs with improved diffusion capabilities, and accurately control molecular concentrations in tissue constructs that may be used in studying models of development and disease or for conditioning cells to enhance survival after insults like ischemia or implantation into the body, thereby providing a framework for better understanding and exploring the characteristics and behaviors of engineered tissue constructs.
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Affiliation(s)
- Richard J McMurtrey
- 1 Institute of Neural Regeneration & Tissue Engineering , Highland, Utah, United States .,2 Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford , Oxford, United Kingdom
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Wei ZZ, Lee JH, Zhang Y, Zhu YB, Deveau TC, Gu X, Winter MM, Li J, Wei L, Yu SP. Intracranial Transplantation of Hypoxia-Preconditioned iPSC-Derived Neural Progenitor Cells Alleviates Neuropsychiatric Defects After Traumatic Brain Injury in Juvenile Rats. Cell Transplant 2016; 25:797-809. [PMID: 26766038 DOI: 10.3727/096368916x690403] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Traumatic brain injury (TBI) is a common cause of mortality and long-term morbidity in children and adolescents. Posttraumatic stress disorder (PTSD) frequently develops in these patients, leading to a variety of neuropsychiatric syndromes. Currently, few therapeutic strategies are available to treat juveniles with PTSD and other developmental neuropsychiatric disorders. In the present investigation, postnatal day 14 (P14) Wistar rats were subjected to TBI induced by a controlled cortical impact (CCI) (velocity = 3 m/s, depth = 2.0 mm, contact time = 150 ms). This TBI injury resulted in not only cortical damages, but also posttrauma social behavior deficits. Three days after TBI, rats were treated with intracranial transplantation of either mouse iPSC-derived neural progenitor cells under normal culture conditions (N-iPSC-NPCs) or mouse iPSC-derived neural progenitor cells pretreated with hypoxic preconditioning (HP-iPSC-NPCs). Compared to TBI animals that received N-iPSC-NPCs or vehicle treatment, HP-iPSC-NPC-transplanted animals showed a unique benefit of improved performance in social interaction, social novelty, and social transmission of food preference tests. Western blotting showed that HP-iPSC-NPCs expressed significantly higher levels of the social behavior-related genes oxytocin and the oxytocin receptor. Overall, HP-iPSC-NPC transplantation exhibits a great potential as a regenerative therapy to improve neuropsychiatric outcomes after juvenile TBI.
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Affiliation(s)
- Zheng Zachory Wei
- Laboratories of Stem Cell Biology and Regenerative Medicine, Department of Neurology, Experimental Research Center and Neurological Disease Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
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57
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The stabilization of hypoxia inducible factor modulates differentiation status and inhibits the proliferation of mouse embryonic stem cells. Chem Biol Interact 2016; 244:204-14. [DOI: 10.1016/j.cbi.2015.12.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 10/26/2015] [Accepted: 12/17/2015] [Indexed: 01/16/2023]
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58
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Fluid Flow Shear Stress Stimulation on a Multiplex Microfluidic Device for Rat Bone Marrow Stromal Cell Differentiation Enhancement. MICROMACHINES 2015. [DOI: 10.3390/mi6121470] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Lee J, Byeon JS, Lee KS, Gu NY, Lee GB, Kim HR, Cho IS, Cha SH. Chondrogenic potential and anti-senescence effect of hypoxia on canine adipose mesenchymal stem cells. Vet Res Commun 2015; 40:1-10. [PMID: 26661466 DOI: 10.1007/s11259-015-9647-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 11/19/2015] [Indexed: 12/24/2022]
Abstract
Mesenchymal stem cells (MSCs) have the ability to differentiate into multi-lineage cells, which confers great promise for use in regenerative medicine. In this study, canine adipose MSCs (cAD-MSCs) were isolated from canine adipose tissue. These cells clearly represented stemness (Oct4, Sox2, and Nanog) and differentiation potential into the mesoderm (adipocytes, chondrocytes, and osteoblasts) at early passages. The aim of this study was to evaluate the effects of hypoxia on the differentiation potential into mesoderm, and the expression of anti-apoptotic genes associated with cell survival for the optimal culturing of MSCs. We observed that the proliferation of the cAD-MSCs meaningfully increased when cultured under hypoxic condition than in normoxic condition, during 7 consecutive passages. Also, we found that hypoxia strongly expressed anti-senescence related genes such as HDAC1 (histone deacetylase 1), DNMT1 (DNA (cytosine-5)-methyltransferase 1), Bcl-2 (inhibitor of apoptosis), TERT (telomerase reverse transcriptase), LDHA (lactate dehydrogenase A), SLC2A1 (glucose transporter), and DKC1 (telomere holoenzyme complex) and differentiation potential of cAD-MSCs into chondrocytes, than seen under the normoxic culture conditions. We also examined the multipotency of hypoxic conditioned MSCs using quantitative real-time RT-PCR. We found that the expression levels of stemness genes such as Oct-4, Nanog, and Sox-2 were increased in hypoxic condition when compared to the normoxic condition. Collectively, these results suggest that hypoxic conditions have the ability to induce proliferation of MSCs and augment their chondrogenic potential. This study suggests that cell proliferation of cAD-MSC under hypoxia could be beneficial, when considering these cells for cell therapies of canine bone diseases.
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Affiliation(s)
- Jienny Lee
- Animal Stem Cells Laboratory, Viral Disease Division, Animal and Plant Quarantine Agency, 175 Anyang-ro, Manan-gu, Anyang-si, Gyeonggi-do, 14089, Republic of Korea
| | - Jeong Su Byeon
- Animal Stem Cells Laboratory, Viral Disease Division, Animal and Plant Quarantine Agency, 175 Anyang-ro, Manan-gu, Anyang-si, Gyeonggi-do, 14089, Republic of Korea
| | - Keum Sil Lee
- Animal Stem Cells Laboratory, Viral Disease Division, Animal and Plant Quarantine Agency, 175 Anyang-ro, Manan-gu, Anyang-si, Gyeonggi-do, 14089, Republic of Korea
| | - Na-Yeon Gu
- Animal Stem Cells Laboratory, Viral Disease Division, Animal and Plant Quarantine Agency, 175 Anyang-ro, Manan-gu, Anyang-si, Gyeonggi-do, 14089, Republic of Korea
| | - Gyeong Been Lee
- Animal Stem Cells Laboratory, Viral Disease Division, Animal and Plant Quarantine Agency, 175 Anyang-ro, Manan-gu, Anyang-si, Gyeonggi-do, 14089, Republic of Korea
| | - Hee-Ryang Kim
- Animal Stem Cells Laboratory, Viral Disease Division, Animal and Plant Quarantine Agency, 175 Anyang-ro, Manan-gu, Anyang-si, Gyeonggi-do, 14089, Republic of Korea
| | - In-Soo Cho
- Animal Stem Cells Laboratory, Viral Disease Division, Animal and Plant Quarantine Agency, 175 Anyang-ro, Manan-gu, Anyang-si, Gyeonggi-do, 14089, Republic of Korea
| | - Sang-Ho Cha
- Animal Stem Cells Laboratory, Viral Disease Division, Animal and Plant Quarantine Agency, 175 Anyang-ro, Manan-gu, Anyang-si, Gyeonggi-do, 14089, Republic of Korea.
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Chen O, Wu M, Jiang L. The Effect of Hypoxic Preconditioning on Induced Schwann Cells under Hypoxic Conditions. PLoS One 2015; 10:e0141201. [PMID: 26509259 PMCID: PMC4624905 DOI: 10.1371/journal.pone.0141201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 10/06/2015] [Indexed: 11/18/2022] Open
Abstract
OBJECT Our objective was to explore the protective effects of hypoxic preconditioning on induced Schwann cells exposed to an environment with low concentrations of oxygen. It has been observed that hypoxic preconditioning of induced Schwann cells can promote axonal regeneration under low oxygen conditions. METHOD Rat bone marrow mesenchymal stem cells (MSCs) were differentiated into Schwann cells and divided into a normal oxygen control group, a hypoxia-preconditioning group and a hypoxia group. The ultrastructure of each of these groups of cells was observed by electron microscopy. In addition, flow cytometry was used to measure changes in mitochondrial membrane potential. Annexin V-FITC/PI staining was used to detect apoptosis, and Western blots were used to detect the expression of Bcl-2/Bax. Fluorescence microscopic observations of axonal growth in NG-108 cells under hypoxic conditions were also performed. RESULTS The hypoxia-preconditioning group maintained mitochondrial cell membrane and crista integrity, and these cells exhibited less edema than the hypoxia group. In addition, the cells in the hypoxia-preconditioning group were found to be in early stages of apoptosis, whereas cells from the hypoxia group were in the later stages of apoptosis. The hypoxia-preconditioning group also had higher levels of Bcl-2/Bax expression and longer NG-108 cell axons than were observed in the hypoxia group. CONCLUSION Hypoxic preconditioning can improve the physiological state of Schwann cells in a severe hypoxia environment and improve the ability to promote neurite outgrowth.
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Affiliation(s)
- Ou Chen
- Department of Orthopedic Surgery, Wenzhou Hospital of Integrated Traditional Chinese and Western Medicine, Wenzhou, Zhejiang, China
| | - Miaomiao Wu
- Department of Orthopedic Surgery, The 2nd Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
- * E-mail:
| | - Liangfu Jiang
- Department of Hand and Plastic Surgery, The 2nd Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
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Choi JH, Lim SM, Yoo YI, Jung J, Park JW, Kim GJ. Microenvironmental Interaction Between Hypoxia and Endothelial Cells Controls the Migration Ability of Placenta-Derived Mesenchymal Stem Cells via α4 Integrin and Rho Signaling. J Cell Biochem 2015; 117:1145-57. [PMID: 26448639 DOI: 10.1002/jcb.25398] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 10/06/2015] [Indexed: 12/13/2022]
Abstract
Mesenchymal stem cells (MSCs) are a powerful source for cell therapy in degenerative diseases. The migration ability of MSCs is an important factor that enhances the therapeutic effect of the cells when they are transplanted into target tissues or organs. Hypoxia and the endothelial barrier, which are representative migration microenvironmental factors, are known to be regulated by the integrin-mediated pathway in several cancers. However, their regulatory mechanisms in MSCs remain unclear. Here, the objectives of the study were to compare the expression of markers related to integrin-mediated signaling in placenta-derived MSCs (PDMSCs) dependent on hypoxia and co-cultured with human umbilical vein endothelial cells (HUVECs) and to evaluate their correlations between migration ability and microenvironmetal factors including hypoxia and endothelial cells. The migration abilities of PDMSCs exposed to hypoxic conditions were significantly increased compared with normal fibroblasts (WI-38) and control (P < 0.05). Interestingly, decreased integrin α4 in PDMSCs under hypoxia induce to increase migration abilities of PDMSCs. Also, Rho family-related markers were significantly increased in PDMSCs under hypoxic conditions compared with normoxia (P < 0.05). Furthermore, the migration ability of PDMSCs was decreased by Rho kinase inhibitor treatment (Y-27632) and co-culturing with HUVECs in an ex vivo system. ROCK activity was increased by inhibiting integrin α4 with HUVECs and hypoxia compared with the absence of HUVECs and under normoxia. The findings suggest microenvironment event by hypoxia and the interaction with endothelial cells may be useful as a regulator of MSC migration and provide insight into the migratory mechanism of MSCs in stem cell-based therapy.
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Affiliation(s)
- Jong Ho Choi
- Department of Biomedical Science, CHA University, Seongnam-si, Republic of Korea
| | - Seung Mook Lim
- Department of Biomedical Science, CHA University, Seongnam-si, Republic of Korea
| | - Yong In Yoo
- Department of Biomedical Science, CHA University, Seongnam-si, Republic of Korea
| | - Jieun Jung
- Department of Nanobiomedical Science, Dankook University, Cheonan-si, Republic of Korea
| | - Jong-Won Park
- Department of Biomedical Sciences and Pharmacology, Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Gi Jin Kim
- Department of Biomedical Science, CHA University, Seongnam-si, Republic of Korea
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Lyons PG, Zadravecz FJ, Edelson DP, Mokhlesi B, Churpek MM. Obstructive sleep apnea and adverse outcomes in surgical and nonsurgical patients on the wards. J Hosp Med 2015; 10:592-8. [PMID: 26073058 PMCID: PMC4560995 DOI: 10.1002/jhm.2404] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 05/11/2015] [Accepted: 05/20/2015] [Indexed: 12/27/2022]
Abstract
BACKGROUND Obstructive sleep apnea (OSA) has been associated with clinical deterioration in postoperative patients and patients hospitalized with pneumonia. Paradoxically, OSA has also been associated with decreased risk of inpatient mortality in these same populations. OBJECTIVES To investigate the association between OSA and in-hospital mortality in a large cohort of surgical and nonsurgical ward patients. DESIGN Observational cohort study. SETTING A 500-bed academic tertiary care hospital in the United States. PATIENTS A total of 93,676 ward admissions from 53,150 unique adult patients between November 1, 2008 and October 1, 2013. INTERVENTION None. MEASUREMENTS OSA diagnoses and comorbidities were identified by International Classification of Diseases, Ninth Revision, Clinical Modification codes. Logistic regression was used to control for patient characteristics, location prior to ward admission, and admission severity of illness. The primary outcome was in-hospital death. Secondary outcomes included rapid response team (RRT) activation, intensive care unit (ICU) transfer, intubation, and cardiac arrest on the wards. MAIN RESULTS OSA was identified in 5,625 (10.6%) patients. Patients with OSA were more likely to be older, male, and obese, and had higher rates of comorbidities. OSA patients had more frequent RRT activations (1.5% vs 1.1%) and ICU transfers (8% vs 7%) than controls (P < 0.001 for both comparisons), but a lower inpatient mortality rate (1.1% vs 1.4%, P < 0.05). OSA was associated with decreased adjusted odds for ICU transfer (odds ratio [OR]: 0.91 [0.84-0.99]), cardiac arrest (OR: 0.72 [0.55-0.95]), and in-hospital mortality (OR: 0.70 [0.58-0.85]). CONCLUSIONS After adjustment for important confounders, OSA was not associated with clinical deterioration on the wards and was associated with significantly decreased in-hospital mortality.
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Affiliation(s)
| | - Frank J. Zadravecz
- University of Chicago Medicine, Department of Medicine, Section of Hospital Medicine, Chicago, IL
| | - Dana P. Edelson
- University of Chicago Medicine, Department of Medicine, Section of Hospital Medicine, Chicago, IL
| | - Babak Mokhlesi
- University of Chicago Medicine, Department of Medicine, Section of Pulmonary and Critical Care Medicine, Chicago, IL
| | - Matthew M. Churpek
- University of Chicago Medicine, Department of Medicine, Section of Pulmonary and Critical Care Medicine, Chicago, IL
- Corresponding author and requests for reprints (Matthew M Churpek), University of Chicago, Section of Pulmonary and Critical Care, 5841 S Maryland Avenue, MC 6076, Chicago, IL 60637,
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Lan YW, Choo KB, Chen CM, Hung TH, Chen YB, Hsieh CH, Kuo HP, Chong KY. Hypoxia-preconditioned mesenchymal stem cells attenuate bleomycin-induced pulmonary fibrosis. Stem Cell Res Ther 2015; 6:97. [PMID: 25986930 PMCID: PMC4487587 DOI: 10.1186/s13287-015-0081-6] [Citation(s) in RCA: 152] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 03/19/2015] [Accepted: 04/21/2015] [Indexed: 12/14/2022] Open
Abstract
INTRODUCTION Idiopathic pulmonary fibrosis is a progressive diffuse parenchymal lung disorder of unknown etiology. Mesenchymal stem cell (MSC)-based therapy is a novel approach with great therapeutic potential for the treatment of lung diseases. Despite demonstration of MSC grafting, the populations of engrafted MSCs have been shown to decrease dramatically 24 hours post-transplantation due to exposure to harsh microenvironments. Hypoxia is known to induce expression of cytoprotective genes and also secretion of anti-inflammatory, anti-apoptotic and anti-fibrotic factors. Hypoxic preconditioning is thought to enhance the therapeutic potency and duration of survival of engrafted MSCs. In this work, we aimed to prolong the duration of survival of engrafted MSCs and to enhance the effectiveness of idiopathic pulmonary fibrosis transplantation therapy by the use of hypoxia-preconditioned MSCs. METHODS Hypoxic preconditioning was achieved in MSCs under an optimal hypoxic environment. The expression levels of cytoprotective factors and their biological effects on damaged alveolar epithelial cells or transforming growth factor-beta 1-treated fibroblast cells were studied in co-culture experiments in vitro. Furthermore, hypoxia-preconditioned MSCs (HP-MSCs) were intratracheally instilled into bleomycin-induced pulmonary fibrosis mice at day 3, and lung functions, cellular, molecular and pathological changes were assessed at 7 and 21 days after bleomycin administration. RESULTS The expression of genes for pro-survival, anti-apoptotic, anti-oxidant and growth factors was upregulated in MSCs under hypoxic conditions. In transforming growth factor-beta 1-treated MRC-5 fibroblast cells, hypoxia-preconditioned MSCs attenuated extracellular matrix production through paracrine effects. The pulmonary respiratory functions significantly improved for up to 18 days of hypoxia-preconditioned MSC treatment. Expression of inflammatory factors and fibrotic factor were all downregulated in the lung tissues of the hypoxia-preconditioned MSC-treated mice. Histopathologic examination observed a significant amelioration of the lung fibrosis. Several LacZ-labeled MSCs were observed within the lungs in the hypoxia-preconditioned MSC treatment groups at day 21, but no signals were detected in the normoxic MSC group. Our data further demonstrated that upregulation of hepatocyte growth factor possibly played an important role in mediating the therapeutic effects of transplanted hypoxia-preconditioned MSCs. CONCLUSION Transplantation of hypoxia-preconditioned MSCs exerted better therapeutic effects in bleomycin-induced pulmonary fibrotic mice and enhanced the survival rate of engrafted MSCs, partially due to the upregulation of hepatocyte growth factor.
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Affiliation(s)
- Ying-Wei Lan
- Division of Biotechnology, Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan, Republic of China.
| | - Kong-Bung Choo
- Department of Preclinical Sciences, Faculty of Medicine and Health Sciences and Centre for Stem Cell Research, Universiti Tunku Abdul Rahman, Selangor, Malaysia.
| | - Chuan-Mu Chen
- Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan, Republic of China.
- Agricultural Biotechnology Center, National Chung Hsing University, Taichung, Taiwan, Republic of China.
- Rong-Hsing Translational Medicine Center, National Chung Hsing University, Taichung, Taiwan, Republic of China.
| | - Tsai-Hsien Hung
- Division of Biotechnology, Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan, Republic of China.
| | - Young-Bin Chen
- Institute of Biotechnology, National Taiwan University, Taichung, Taiwan, Republic of China.
| | - Chung-Hsing Hsieh
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan, Republic of China.
- Department of Thoracic Medicine, St Paul's Hospital, Taoyuan, Taiwan, Republic of China.
- Department of Thoracic Medicine, Ton-Yen General Hospital, Hsinchu, Taiwan, Republic of China.
| | - Han-Pin Kuo
- Department of Thoracic Medicine, Pulmonary Disease Research Center, Chang Gung Memorial Hospital, Taipei, Taiwan, Republic of China.
- Department of Medicine, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan, Republic of China.
| | - Kowit-Yu Chong
- Division of Biotechnology, Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan, Republic of China.
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan, Republic of China.
- Molecular Medicine Research Center, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan, Republic of China.
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Sung JH, An HS, Jeong JH, Shin S, Song SY. Megestrol Acetate Increases the Proliferation, Migration, and Adipogenic Differentiation of Adipose-Derived Stem Cells via Glucocorticoid Receptor. Stem Cells Transl Med 2015; 4:789-99. [PMID: 25972147 DOI: 10.5966/sctm.2015-0009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2015] [Accepted: 04/08/2015] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED : Because adipose-derived stem cells (ASCs) are usually expanded to acquire large numbers of cells for therapeutic applications, it is important to increase the production yield and regenerative potential during expansion. Therefore, a tremendous need exists for alternative ASC stimuli during cultivation to increase the proliferation and adipogenic differentiation of ASCs. The present study primarily investigated the involvement of megestrol acetate (MA), a progesterone analog, in the stimulation of ASCs, and identifies the target receptors underlying stimulation. Mitogenic and adipogenic effects of MA were investigated in vitro, and pharmacological inhibition and small interfering (si) RNA techniques were used to identify the molecular mechanisms involved in the MA-induced stimulation of ASCs. MA significantly increased the proliferation, migration, and adipogenic differentiation of ASCs in a dose-dependent manner. Glucocorticoid receptor (GR) is highly expressed compared with other nuclear receptors in ASCs, and this receptor is phosphorylated after MA treatment. MA also upregulated genes downstream of GR in ASCs, including ANGPTL4, DUSP1, ERRF11, FKBP5, GLUL, and TSC22D3. RU486, a pharmacological inhibitor of GR, and transfection of siGR significantly attenuated MA-induced proliferation, migration, and adipogenic differentiation of ASCs. Although the adipogenic differentiation potential of MA was inferior to that of dexamethasone, MA had mitogenic effects in ASCs. Collectively, these results indicate that MA increases the proliferation, migration, and adipogenic differentiation of ASCs via GR phosphorylation. SIGNIFICANCE Magestrol acetate (MA) increases the proliferation, migration, and adipogenic differentiation of adipose-derived stem cells (ASCs) via glucocorticoid receptor phosphorylation. Therefore, MA can be applied to increase the production yield during expansion and can be used to facilitate adipogenic differentiation of ASCs.
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Affiliation(s)
- Jong-Hyuk Sung
- College of Pharmacy, Yonsei University, Incheon, Republic of Korea; STEMORE Co. Ltd., Incheon, Republic of Korea; College of Pharmacy, Wonkwang University, Iksan, Republic of Korea; Institute for Human Tissue Restoration, Department of Plastic and Reconstructive Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Hyo-Sun An
- College of Pharmacy, Yonsei University, Incheon, Republic of Korea; STEMORE Co. Ltd., Incheon, Republic of Korea; College of Pharmacy, Wonkwang University, Iksan, Republic of Korea; Institute for Human Tissue Restoration, Department of Plastic and Reconstructive Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jin-Hyun Jeong
- College of Pharmacy, Yonsei University, Incheon, Republic of Korea; STEMORE Co. Ltd., Incheon, Republic of Korea; College of Pharmacy, Wonkwang University, Iksan, Republic of Korea; Institute for Human Tissue Restoration, Department of Plastic and Reconstructive Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Soyoung Shin
- College of Pharmacy, Yonsei University, Incheon, Republic of Korea; STEMORE Co. Ltd., Incheon, Republic of Korea; College of Pharmacy, Wonkwang University, Iksan, Republic of Korea; Institute for Human Tissue Restoration, Department of Plastic and Reconstructive Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Seung Yong Song
- College of Pharmacy, Yonsei University, Incheon, Republic of Korea; STEMORE Co. Ltd., Incheon, Republic of Korea; College of Pharmacy, Wonkwang University, Iksan, Republic of Korea; Institute for Human Tissue Restoration, Department of Plastic and Reconstructive Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea
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Sun J, Wei ZZ, Gu X, Zhang JY, Zhang Y, Li J, Wei L. Intranasal delivery of hypoxia-preconditioned bone marrow-derived mesenchymal stem cells enhanced regenerative effects after intracerebral hemorrhagic stroke in mice. Exp Neurol 2015; 272:78-87. [PMID: 25797577 DOI: 10.1016/j.expneurol.2015.03.011] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 03/10/2015] [Accepted: 03/13/2015] [Indexed: 12/11/2022]
Abstract
Intracerebral hemorrhagic stroke (ICH) causes high mortality and morbidity with very limited treatment options. Cell-based therapy has emerged as a novel approach to replace damaged brain tissues and promote regenerative processes. In this study we tested the hypothesis that intranasally delivered hypoxia-preconditioned BMSCs could reach the brain, promote tissue repair and improve functional recovery after ICH. Hemorrhagic stroke was induced in adult C57/B6 mice by injection of collagenase IV into the striatum. Animals were randomly divided into three groups: sham group, intranasal BMSC treatment group, and vehicle treatment group. BMSCs were pre-treated with hypoxic preconditioning (HP) and pre-labeled with Hoechst before transplantation. Behavior tests, including the mNSS score, rotarod test, adhesive removal test, and locomotor function evaluation were performed at varying days, up to 21days, after ICH to evaluate the therapeutic effects of BMSC transplantation. Western blots and immunohistochemistry were performed to analyze the neurotrophic effects. Intranasally delivered HP-BMSCs were identified in peri-injury regions. NeuN+/BrdU+ co-labeled cells were markedly increased around the hematoma region, and growth factors, including BDNF, GDNF, and VEGF were significantly upregulated in the ICH brain after BMSC treatment. The BMSC treatment group showed significant improvement in behavioral performance compared with the vehicle group. Our data also showed that intranasally delivered HP-BMSCs migrated to peri-injury regions and provided growth factors to increase neurogenesis after ICH. We conclude that intranasal administration of BMSC is an effective treatment for ICH, and that it enhanced neuroregenerative effects and promoted neurological functional recovery after ICH. Overall, the investigation supports the potential therapeutic strategy for BMSC transplantation therapy against hemorrhagic stroke.
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Affiliation(s)
- Jinmei Sun
- Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China; Laboratories of Stem Cell Biology and Neural Regeneration and Function Recovery, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China; Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Zheng Zachory Wei
- Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China; Laboratories of Stem Cell Biology and Neural Regeneration and Function Recovery, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China; Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Xiaohuan Gu
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - James Ya Zhang
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Yongbo Zhang
- Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China; Laboratories of Stem Cell Biology and Neural Regeneration and Function Recovery, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
| | - Jimei Li
- Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China; Laboratories of Stem Cell Biology and Neural Regeneration and Function Recovery, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China.
| | - Ling Wei
- Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China; Laboratories of Stem Cell Biology and Neural Regeneration and Function Recovery, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China; Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA.
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Wang X, Liu C, Li S, Xu Y, Chen P, Liu Y, Ding Q, Wahafu W, Hong B, Yang M. Hypoxia precondition promotes adipose-derived mesenchymal stem cells based repair of diabetic erectile dysfunction via augmenting angiogenesis and neuroprotection. PLoS One 2015; 10:e0118951. [PMID: 25790284 PMCID: PMC4366267 DOI: 10.1371/journal.pone.0118951] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Accepted: 01/20/2015] [Indexed: 12/16/2022] Open
Abstract
The aim of the present study was to examine whether hypoxia preconditioning could improve therapeutic effects of adipose derived mesenchymal stem cells (AMSCs) for diabetes induced erectile dysfunction (DED). AMSCs were pretreated with normoxia (20% O2, N-AMSCs) or sub-lethal hypoxia (1% O2, H-AMSCs). The hypoxia exposure up-regulated the expression of several angiogenesis and neuroprotection related cytokines in AMSCs, including vascular endothelial growth factor (VEGF) and its receptor FIK-1, angiotensin (Ang-1), basic fibroblast growth factor (bFGF), brain-derived neurotrophic factor (BDNF), glial cell-derived neurotrophic factor (GDNF), stromal derived factor-1 (SDF-1) and its CXC chemokine receptor 4 (CXCR4). DED rats were induced via intraperitoneal injection of streptozotocin (60 mg/kg) and were randomly divided into three groups—Saline group: intracavernous injection with phosphate buffer saline; N-AMSCs group: N-AMSCs injection; H-AMSCs group: H-AMSCs injection. Ten rats without any treatment were used as normal control. Four weeks after injection, the mean arterial pressure (MAP) and intracavernosal pressure (ICP) were measured. The contents of endothelial, smooth muscle, dorsal nerve in cavernoursal tissue were assessed. Compared with N-AMSCs and saline, intracavernosum injection of H-AMSCs significantly raised ICP and ICP/MAP (p<0.05). Immunofluorescent staining analysis demonstrated that improved erectile function by MSCs was significantly associated with increased expression of endothelial markers (CD31 and vWF) (p<0.01) and smooth muscle markers (α-SMA) (p<0.01). Meanwhile, the expression of nNOS was also significantly higher in rats receiving H-AMSCs injection than those receiving N-AMSCs or saline injection. The results suggested that hypoxic preconditioning of MSCs was an effective approach to enhance their therapeutic effect for DED, which may be due to their augmented angiogenesis and neuroprotection.
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Affiliation(s)
- XiYou Wang
- Department of Traditional Chinese Medicine, Chinese People’s Liberation Army General Hospital, No 28 Fuxing Road, Hai dian District, Beijing 100853, People’s Republic of China
| | - CuiLong Liu
- Department of Urology, PLA Navy General Hospital, No 6 Fucheng Road, Hai dian District, Beijing 100048, People’s Republic of China
| | - ShaoDan Li
- Department of Traditional Chinese Medicine, Chinese People’s Liberation Army General Hospital, No 28 Fuxing Road, Hai dian District, Beijing 100853, People’s Republic of China
| | - Yong Xu
- Department of Urology, Chinese People’s Liberation Army General Hospital, No 28 Fuxing Road, Hai dian District, Beijing 100853, People’s Republic of China
| | - Ping Chen
- Department of Urology, Chinese People’s Liberation Army General Hospital, No 28 Fuxing Road, Hai dian District, Beijing 100853, People’s Republic of China
| | - Yi Liu
- Department of Traditional Chinese Medicine, Chinese People’s Liberation Army General Hospital, No 28 Fuxing Road, Hai dian District, Beijing 100853, People’s Republic of China
| | - Qiang Ding
- Department of Urology, Chinese People’s Liberation Army General Hospital, No 28 Fuxing Road, Hai dian District, Beijing 100853, People’s Republic of China
| | - Wasilijiang Wahafu
- Department of Urology, Chinese People’s Liberation Army General Hospital, No 28 Fuxing Road, Hai dian District, Beijing 100853, People’s Republic of China
| | - BaoFa Hong
- Department of Urology, Chinese People’s Liberation Army General Hospital, No 28 Fuxing Road, Hai dian District, Beijing 100853, People’s Republic of China
| | - MingHui Yang
- Department of Traditional Chinese Medicine, Chinese People’s Liberation Army General Hospital, No 28 Fuxing Road, Hai dian District, Beijing 100853, People’s Republic of China
- * E-mail:
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Peng L, Shu X, Lang C, Yu X. Effects of hypoxia on proliferation of human cord blood-derived mesenchymal stem cells. Cytotechnology 2015; 68:1615-22. [PMID: 25742732 DOI: 10.1007/s10616-014-9818-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2014] [Accepted: 11/10/2014] [Indexed: 12/21/2022] Open
Abstract
The purpose of our study was to examine the influence of hypoxia on proliferation of human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs). The mononuclear cells were separated by density gradient centrifugation from human umbilical cord blood and then, respectively, cultured under hypoxia (5 % O2) or normoxia (20 % O2). Their cell morphology, cell surface markers, β-galactosidase staining, cell growth curve, DNA cycle, and the expression of hypoxia-inducible factor-1α (HIF-1α) were evaluated. We found that hypoxia, in part via HIF-1α, improved the proliferation efficiency, and prevented senescence of hUCB-MSCs without altering their morphology and surface markers. These results demonstrated that hypoxia provides a favorable culture condition to promote hUCB-MSCs proliferation in vitro, which is a better way to obtain sufficient numbers of hUCB-MSCs for research and certainly clinical application.
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Affiliation(s)
- Longying Peng
- Department of Pediatric, First Affiliated Hospital, Zunyi Medical College, Zunyi, 563003, Guizhou, China
| | - Xiaomei Shu
- Department of Pediatric, First Affiliated Hospital, Zunyi Medical College, Zunyi, 563003, Guizhou, China.
| | - Changhui Lang
- Department of Pediatric, First Affiliated Hospital, Zunyi Medical College, Zunyi, 563003, Guizhou, China
| | - Xiaohua Yu
- Department of Pediatric, First Affiliated Hospital, Zunyi Medical College, Zunyi, 563003, Guizhou, China
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Yoo M, Lee GA, Park C, Cohen RI, Schachner M. Analysis of human embryonic stem cells with regulatable expression of the cell adhesion molecule l1 in regeneration after spinal cord injury. J Neurotrauma 2014; 31:553-64. [PMID: 24125017 DOI: 10.1089/neu.2013.2886] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Cell replacement therapy is one potential avenue for central nervous system (CNS) repair. However, transplanted stem cells may not contribute to long-term recovery of the damaged CNS unless they are engineered for functional advantage. To fine tune regenerative capabilities, we developed a human neural cell line expressing L1, a regeneration-conducive adhesion molecule, under the control of a doxycycline regulatable Tet-off promoter. Controlled expression of L1 is desired because overexpression after regenerative events may lead to adverse consequences. The regulated system was tested in several cell lines, where doxycycline completely eliminated green fluorescent protein or L1 expression by 3-5 days in vitro. Increased colony formation as well as decreased proliferation were observed in H9NSCs without doxycycline (hL1-on). To test the role of L1 in vivo after acute compression spinal cord injury of immunosuppressed mice, quantum dot labeled hL1-on or hL1-off cells were injected at three sites: lesion; proximal; and caudal. Mice transplanted with hL1-on cells showed a better Basso Mouse Scale score, when compared to those with hL1-off cells. As compared to the hL1-off versus hL1-on cell transplanted mice 6 weeks post-transplantation, expression levels of L1, migration of transplanted cells, and immunoreactivity for tyrosine hydroxylase were higher, whereas expression of chondroitin sulfate proteoglycans was lower. Results indicate that L1 expression is regulatable in human stem cells by doxycycline in a nonviral engineering approach. Regulatable expression in a prospective nonleaky Tet-off system could hold promise for therapy, based on the multifunctional roles of L1, including neuronal migration and survival, neuritogenesis, myelination, and synaptic plasticity.
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Affiliation(s)
- Myungsik Yoo
- 1 W.M. Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University , Piscataway, New Jersey
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Sart S, Liu Y, Ma T, Li Y. Microenvironment Regulation of Pluripotent Stem Cell-Derived Neural Progenitor Aggregates by Human Mesenchymal Stem Cell Secretome. Tissue Eng Part A 2014; 20:2666-79. [DOI: 10.1089/ten.tea.2013.0437] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Affiliation(s)
- Sébastien Sart
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, Florida
| | - Yijun Liu
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, Florida
| | - Teng Ma
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, Florida
| | - Yan Li
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, Florida
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Liu XB, Wang JA, Ji XY, Yu SP, Wei L. Preconditioning of bone marrow mesenchymal stem cells by prolyl hydroxylase inhibition enhances cell survival and angiogenesis in vitro and after transplantation into the ischemic heart of rats. Stem Cell Res Ther 2014; 5:111. [PMID: 25257482 PMCID: PMC4535299 DOI: 10.1186/scrt499] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 07/16/2014] [Indexed: 01/25/2023] Open
Abstract
INTRODUCTION Poor cell survival and limited functional benefits have restricted the efficacy of bone marrow mesenchymal stem cells (BMSCs) in the treatment of myocardial infarction. We showed recently that hypoxia preconditioning of BMSCs and neural progenitor cells before transplantation can enhance the survival and therapeutic properties of these cells in the ischemic brain and heart. The present investigation explores a novel strategy of preconditioning BMSCs using the Hypoxia-inducible factor 1α (HIF-α) prolyl hydroxylase inhibitor dimethyloxalylglycine (DMOG) to enhance their survival and therapeutic efficacy after transplantation into infarcted myocardium. METHODS BMSCs from green fluorescent protein transgenic rats were cultured with or without 1 mM DMOG for 24 hours in complete culture medium before transplantation. Survival and angiogenic factors were evaluated in vitro by trypan blue staining, Western blotting, and tube formation test. In an ischemic heart model of rats, BMSCs with and without DMOG preconditioning were intramyocardially transplanted into the peri-infarct region 30 minutes after permanent myocardial ischemia. Cell death was measured 24 hours after engraftment. Heart function, angiogenesis and infarct size were measured 4 weeks later. RESULTS In DMOG preconditioned BMSCs (DMOG-BMSCs), the expression of survival and angiogenic factors including HIF-1α, vascular endothelial growth factor, glucose transporter 1 and phospho-Akt were significantly increased. In comparison with control cells, DMOG-BMSCs showed higher viability and enhanced angiogenesis in both in vitro and in vivo assays. Transplantation of DMOG-BMSCs reduced heart infarct size and promoted functional benefits of the cell therapy. CONCLUSIONS We suggest that DMOG preconditioning enhances the survival capability of BMSCs and paracrine effects with increased differentiation potential. Prolyl hydroxylase inhibition is an effective and feasible strategy to enhance therapeutic efficacy and efficiency of BMSC transplantation therapy after heart ischemia.
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Amiri F, Halabian R, Salimian M, Shokrgozar MA, Soleimani M, Jahanian-Najafabadi A, Roudkenar MH. Induction of multipotency in umbilical cord-derived mesenchymal stem cells cultivated under suspension conditions. Cell Stress Chaperones 2014; 19:657-66. [PMID: 24464492 PMCID: PMC4147073 DOI: 10.1007/s12192-014-0491-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 12/19/2013] [Accepted: 01/01/2014] [Indexed: 12/18/2022] Open
Abstract
Due to the limitations in the clinical application of embryonic stem cells (ESC) and induced pluripotent stem cells, mesenchymal stem cells (MSCs) are now much more interesting for cell-based therapy. Although MSCs have several advantages, they are not capable of differentiating to all three embryonic layers (three germ layers) without cultivation under specific induction media. Hence, improvement of MSCs for cell therapy purposes is under intensive study now. In this study, we isolated MSCs from umbilical cord tissue at the single-cell level, by treatment with trypsin, followed by cultivation under suspension conditions to form a colony. These colonies were trypsin resistant, capable of self-renewal differentiation to the three germ layers without any induction, and they were somewhat similar to ESC colonies. The cells were able to grow in both adherent and suspension culture conditions, expressed both the MSCs markers, especially CD105, and the multipotency markers, i.e., SSEA-3, and had a limited lifespan. The cells were expanded under simple culture conditions at the single-cell level and were homogenous. Further and complementary studies are required to understand how trypsin-tolerant mesenchymal stem cells are established. However, our study suggested non-embryonic resources for future cell-based therapy.
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Affiliation(s)
- Fatemeh Amiri
- />Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran
| | - Raheleh Halabian
- />Applied Microbiology Research Center, Medical Science of Baqiyatallah University, Tehran, Iran
| | - Morteza Salimian
- />Department of Medical Laboratory, Kashan University of Medical Sciences and Health, Kashan, Iran
| | | | - Masoud Soleimani
- />Department of Hematology, School of Medical Sciences, Tarbiat Modarres University, Tehran, Iran
| | - Ali Jahanian-Najafabadi
- />Department of Pharmaceutical Biotechnology and Bioinformatics Research Center, School of Pharmacy, Isfahan University of Medical Sciences and Health Services, Isfahan, Iran
| | - Mehryar Habibi Roudkenar
- />Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran
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Abstract
Stem cell transplantation therapy has emerged as a promising regenerative medicine for ischemic stroke and other neurodegenerative disorders. However, many issues and problems remain to be resolved before successful clinical applications of the cell-based therapy. To this end, some recent investigations have sought to benefit from well-known mechanisms of ischemic/hypoxic preconditioning. Ischemic/hypoxic preconditioning activates endogenous defense mechanisms that show marked protective effects against multiple insults found in ischemic stroke and other acute attacks. As in many other cell types, a sub-lethal hypoxic exposure significantly increases the tolerance and regenerative properties of stem cells and progenitor cells. So far, a variety of preconditioning triggers have been tested on different stem cells and progenitor cells. Preconditioned stem cells and progenitors generally show much better cell survival, increased neuronal differentiation, enhanced paracrine effects leading to increased trophic support, and improved homing to the lesion site. Transplantation of preconditioned cells helps to suppress inflammatory factors and immune responses, and promote functional recovery. Although the preconditioning strategy in stem cell therapy is still an emerging research area, accumulating information from reports over the last few years already indicates it as an attractive, if not essential, prerequisite for transplanted cells. It is expected that stem cell preconditioning and its clinical applications will attract more attention in both the basic research field of preconditioning as well as in the field of stem cell translational research. This review summarizes the most important findings in this active research area, covering the preconditioning triggers, potential mechanisms, mediators, and functional benefits for stem cell transplant therapy.
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Affiliation(s)
- Shan Ping Yu
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
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Lee IC, Wu YC. Assembly of polyelectrolyte multilayer films on supported lipid bilayers to induce neural stem/progenitor cell differentiation into functional neurons. ACS APPLIED MATERIALS & INTERFACES 2014; 6:14439-50. [PMID: 25111699 DOI: 10.1021/am503750w] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The key factors affecting the success of neural engineering using neural stem/progenitor cells (NSPCs) are the neuron quantity, the guidance of neurite outgrowth, and the induction of neurons to form functional synapses at synaptic junctions. Herein, a biomimetic material comprising a supported lipid bilayer (SLB) with adsorbed sequential polyelectrolyte multilayer (PEM) films was fabricated to induce NSPCs to form functional neurons without the need for serum and growth factors in a short-term culture. SLBs are suitable artificial substrates for neural engineering due to their structural similarity to synaptic membranes. In addition, PEM film adsorption provides protection for the SLB as well as the ability to vary the surface properties to evaluate the effects of physical and mechanical signals on NSPC differentiation. Our results revealed that NSPCs were inducible on SLB-PEM films consisting of up to eight alternating layers. In addition, the process outgrowth length, the percentage of differentiated neurons, and the synaptic function were regulated by the number of layers and the surface charge of the outermost layer. The average process outgrowth length was greater than 500 μm on SLB-PLL/PLGA (n = 7.5) after only 3 days of culture. Moreover, the quantity and quality of the differentiated neurons were obviously enhanced on the SLB-PEM system compared with those on the PEM-only substrates. These results suggest that the PEM films can induce NSPC adhesion and differentiation and that an SLB base may enhance neuron differentiation and trigger the formation of functional synapses.
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Affiliation(s)
- I-Chi Lee
- Graduate Institute of Biochemical and Biomedical Engineering, Chang-Gung University , No. 259, Wenhua First Road, Guishan Township, Taoyuan County, 33302, Taiwan (R.O.C.)
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Abstract
Stem cells have emerged as promising tools for the treatment of incurable neural and heart diseases and tissue damage. However, the survival of transplanted stem cells is reported to be low, reducing their therapeutic effects. The major causes of poor survival of stem cells in vivo are linked to anoikis, potential immune rejection, and oxidative damage mediating apoptosis. This review investigates novel methods and potential molecular mechanisms for stem cell preconditioning in vitro to increase their retention after transplantation in damaged tissues. Microenvironmental preconditioning (e.g., hypoxia, heat shock, and exposure to oxidative stress), aggregate formation, and hydrogel encapsulation have been revealed as promising strategies to reduce cell apoptosis in vivo while maintaining biological functions of the cells. Moreover, this review seeks to identify methods of optimizing cell dose preparation to enhance stem cell survival and therapeutic function after transplantation.
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Affiliation(s)
- Sébastien Sart
- Hydrodynamics Laboratory , CNRS UMR7646, Ecole Polytechnique, Palaiseau, France
| | - Teng Ma
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University , Tallahassee, Florida
| | - Yan Li
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University , Tallahassee, Florida
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75
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Benitez SG, Castro AE, Patterson SI, Muñoz EM, Seltzer AM. Hypoxic preconditioning differentially affects GABAergic and glutamatergic neuronal cells in the injured cerebellum of the neonatal rat. PLoS One 2014; 9:e102056. [PMID: 25032984 PMCID: PMC4102512 DOI: 10.1371/journal.pone.0102056] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 06/13/2014] [Indexed: 12/13/2022] Open
Abstract
In this study we examined cerebellar alterations in a neonatal rat model of hypoxic-ischemic brain injury with or without hypoxic preconditioning (Pc). Between postnatal days 7 and 15, the cerebellum is still undergoing intense cellular proliferation, differentiation and migration, dendritogenesis and synaptogenesis. The expression of glutamate decarboxylase 1 (GAD67) and the differentiation factor NeuroD1 were examined as markers of Purkinje and granule cells, respectively. We applied quantitative immunohistochemistry to sagittal cerebellar slices, and Western blot analysis of whole cerebella obtained from control (C) rats and rats submitted to Pc, hypoxia-ischemia (L) and a combination of both treatments (PcL). We found that either hypoxia-ischemia or Pc perturbed the granule cells in the posterior lobes, affecting their migration and final placement in the internal granular layer. These effects were partially attenuated when the Pc was delivered prior to the hypoxia-ischemia. Interestingly, whole nuclear NeuroD1 levels in Pc animals were comparable to those in the C rats. However, a subset of Purkinje cells that were severely affected by the hypoxic-ischemic insult—showing signs of neuronal distress at the levels of the nucleus, cytoplasm and dendritic arborization—were not protected by Pc. A monoclonal antibody specific for GAD67 revealed a three-band pattern in cytoplasmic extracts from whole P15 cerebella. A ∼110 kDa band, interpreted as a potential homodimer of a truncated form of GAD67, was reduced in Pc and L groups while its levels were close to the control animals in PcL rats. Additionally we demonstrated differential glial responses depending on the treatment, including astrogliosis in hypoxiated cerebella and a selective effect of hypoxia-ischemia on the vimentin-immunolabeled intermediate filaments of the Bergmann glia. Thus, while both glutamatergic and GABAergic cerebellar neurons are compromised by the hypoxic-ischemic insult, the former are protected by a preconditioning hypoxia while the latter are not.
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Affiliation(s)
- Sergio G Benitez
- Laboratory of Neurobiology: Chronobiology Section, Institute of Histology and Embryology of Mendoza (IHEM), School of Medicine, National University of Cuyo, Mendoza, National Scientific and Technical Research Council (CONICET), National Agency for Scientific and Technological Promotion (ANPCyT), Mendoza, Argentina
| | - Analía E Castro
- Laboratory of Neurobiology: Chronobiology Section, Institute of Histology and Embryology of Mendoza (IHEM), School of Medicine, National University of Cuyo, Mendoza, National Scientific and Technical Research Council (CONICET), National Agency for Scientific and Technological Promotion (ANPCyT), Mendoza, Argentina
| | - Sean I Patterson
- Traumatic and Toxic Lesions in the Nervous System Section, Institute of Histology and Embryology of Mendoza (IHEM), School of Medicine, National University of Cuyo, Mendoza, National Scientific and Technical Research Council (CONICET), National Agency for Scientific and Technological Promotion (ANPCyT), Mendoza, Argentina
| | - Estela M Muñoz
- Laboratory of Neurobiology: Chronobiology Section, Institute of Histology and Embryology of Mendoza (IHEM), School of Medicine, National University of Cuyo, Mendoza, National Scientific and Technical Research Council (CONICET), National Agency for Scientific and Technological Promotion (ANPCyT), Mendoza, Argentina
| | - Alicia M Seltzer
- Neonatal Brain Development Section, Institute of Histology and Embryology of Mendoza (IHEM), School of Medicine, National University of Cuyo, Mendoza, National Scientific and Technical Research Council (CONICET), National Agency for Scientific and Technological Promotion (ANPCyT), Mendoza, Argentina
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76
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Hawkins KE, Sharp TV, McKay TR. The role of hypoxia in stem cell potency and differentiation. Regen Med 2014; 8:771-82. [PMID: 24147532 DOI: 10.2217/rme.13.71] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Regenerative medicine relies on harnessing the capacity of stem cells to grow, divide and differentiate safely and predictably. This may be in the context of expanding stem cells in vitro or encouraging their expansion, mobilization and capacity to regenerate tissues either locally or remotely in vivo. In either case, understanding the stem cell niche is fundamental to recapitulating or manipulating conditions to enable therapy. It has become obvious that hypoxia plays a fundamental role in the maintenance of the stem cell niche. Low O2 benefits the self-renewal of human embryonic, hematopoietic, mesenchymal and neural stem cells, as well as improving the efficiency of genetic reprogramming to induced pluripotency. There is emerging evidence that harnessing or manipulating the hypoxic response can result in safer, more efficacious methodologies for regenerative medicine.
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Affiliation(s)
- Kate E Hawkins
- Division of Biomedical Sciences, St George's University of London, Cranmer Terrace, London, SW17 0RE, UK
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77
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Choi YC, Choi JS, Woo CH, Cho YW. Stem cell delivery systems inspired by tissue-specific niches. J Control Release 2014; 193:42-50. [PMID: 24979211 DOI: 10.1016/j.jconrel.2014.06.032] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 05/29/2014] [Accepted: 06/06/2014] [Indexed: 12/18/2022]
Abstract
Since stem cells have the capacity to differentiate into a variety of cell types, stem cell delivery systems (SCDSs) can be effective therapeutic strategies for a multitude of diseases and disorders. For stem cell-based therapy, stem cells are introduced directly (or peripherally) into a target tissue via different delivery systems. Despite initial promising results obtained from preclinical studies, a number of technical hurdles must be overcome for ultimate clinical utility of stem cells. A key aspect of SCDSs is how to create local environments, called stem cell niches, for improvement of survival and engraftment as well as the fate of transplanted stem cells. The stem cell niches encompassing a wide range of biochemical, biophysical, and biomechanical cues play a guidance role to modulate stem cell behaviors such as adhesion, proliferation, and differentiation. Recent studies have tried to decipher the complex interplay between stem cells and niches, and thereafter to engineer SCDS, mimicking dynamic stem cell niches encompassing a wide range of biochemical, biophysical, and biomechanical cues. Here, we discuss the biological role of stem cell niches and highlight recent progress in SCDS to mimic stem cell niches, particularly focusing on important biomaterial properties for modulating stem cell fate.
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Affiliation(s)
- Young Chan Choi
- Department of Chemical Engineering, Hanyang University, Ansan, Gyeonggi-do 426-791, South Korea
| | - Ji Suk Choi
- Department of Chemical Engineering, Hanyang University, Ansan, Gyeonggi-do 426-791, South Korea
| | - Chang Hee Woo
- Department of Chemical Engineering, Hanyang University, Ansan, Gyeonggi-do 426-791, South Korea
| | - Yong Woo Cho
- Department of Chemical Engineering, Hanyang University, Ansan, Gyeonggi-do 426-791, South Korea.
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78
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Yang Z, Zhu L, Li F, Wang J, Wan H, Pan Y. Bone marrow stromal cells as a therapeutic treatment for ischemic stroke. Neurosci Bull 2014; 30:524-34. [PMID: 24817388 DOI: 10.1007/s12264-013-1431-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 12/12/2013] [Indexed: 12/15/2022] Open
Abstract
Cerebral ischemia remains the most frequent cause of death and quality-of-life impairments due to neurological deficits, and accounts for the majority of total healthcare costs. However, treatments for cerebral ischemia are limited. Over the last decade, bone marrow stromal cell (BMSC) therapy has emerged as a particularly appealing option, as it is possible to help patients even when initiated days or even weeks after the ischemic insult. BMSCs are a class of multipotent, self-renewing cells that give rise to differentiated progeny when implanted into appropriate tissues. Therapeutic effects of BMSC treatment for ischemic stroke, including sensory and motor recovery, have been reported in pre-clinical studies and clinical trials. In this article, we review the recent progress in BMSC-based therapy for ischemic stroke, focusing on the route of delivery and pre-processing of BMSCs. Selecting an optimal delivery route is of particular importance. The ideal approach, as well as the least risky, for translational applications still requires further identification. Appropriate preprocessing of BMSCs or combination therapy has the benefit of achieving the maximum possible restoration. Further pre-clinical studies are required to determine the time-window for transplantation and the appropriate dosage of cells.
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Affiliation(s)
- Zizhen Yang
- Department of Neurology, First Hospital and Clinical College, Harbin Medical University, Harbin, 150001, China
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79
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Kim JH, Kim WK, Sung YK, Kwack MH, Song SY, Choi JS, Park SG, Yi T, Lee HJ, Kim DD, Seo HM, Song SU, Sung JH. The molecular mechanism underlying the proliferating and preconditioning effect of vitamin C on adipose-derived stem cells. Stem Cells Dev 2014; 23:1364-76. [PMID: 24524758 DOI: 10.1089/scd.2013.0460] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Although adipose-derived stem cells (ASCs) show promise for cell therapy, there is a tremendous need for developing ASC activators. In the present study, we investigated whether or not vitamin C increases the survival, proliferation, and hair-regenerative potential of ASCs. In addition, we tried to find the molecular mechanisms underlying the vitamin C-mediated stimulation of ASCs. Sodium-dependent vitamin C transporter 2 (SVCT2) is expressed in ASCs, and mediates uptake of vitamin C into ASCs. Vitamin C increased the survival and proliferation of ASCs in a dose-dependent manner. Vitamin C increased ERK1/2 phosphorylation, and inhibition of the mitogen-activated protein kinase (MAPK) pathway attenuated the proliferation of ASCs. Microarray and quantitative polymerase chain reaction showed that vitamin C primarily upregulated expression of proliferation-related genes, including Fos, E2F2, Ier2, Mybl1, Cdc45, JunB, FosB, and Cdca5, whereas Fos knock-down using siRNA significantly decreased vitamin C-mediated ASC proliferation. In addition, vitamin C-treated ASCs accelerated the telogen-to-anagen transition in C3H/HeN mice, and conditioned medium from vitamin C-treated ASCs increased the hair length and the Ki67-positive matrix keratinocytes in hair organ culture. Vitamin C increased the mRNA expression of HGF, IGFBP6, VEGF, bFGF, and KGF, which may mediate hair growth promotion. In summary, vitamin C is transported via SVCT2, and increased ASC proliferation is mediated by the MAPK pathway. In addition, vitamin C preconditioning enhanced the hair growth promoting effect of ASCs. Because vitamin C is safe and effective, it could be used to increase the yield and regenerative potential of ASCs.
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Affiliation(s)
- Ji Hye Kim
- 1 Department of Applied Bioscience, CHA University , Seoul, Korea
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80
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Mohamad O, Yu SP, Chen D, Ogle M, Song M, Wei L. Efficient neuronal differentiation of mouse ES and iPS cells using a rotary cell culture protocol. Differentiation 2014; 86:149-58. [PMID: 24480155 DOI: 10.1016/j.diff.2013.12.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 10/28/2013] [Accepted: 12/05/2013] [Indexed: 02/01/2023]
Abstract
Embryonic stem (ES) cells and induced pluripotent stem (iPS) cells hold great promise in regenerative medicine for the treatment of neurodegenerative diseases. Current neuronal differentiation protocols however, are not optimized yet for the high scale production of neural precursors and terminally differentiated neurons. The present investigation reports a novel technique for the scalable production of highly uniformed neurospheres, neural precursors and terminal neurons from mouse ES and iPS cells using retinoic acid and a mechanical rotation procedure. We compared embryoid bodies (EB) and neurosphere morphology, yield of neural precursors and quality of neurons between rotary and static suspension cultures of mouse ES and iPS cells undergoing neural differentiation. Analysis of neurospheres formed under continuous rotation showed increased neurosphere uniformity and a high yield of neural precursors after neurosphere dissociation. Neurospheres formed under rotation conditions were relatively smaller, more uniform and had less dead cells and higher proliferation compared to those formed under static conditions. Neural precursors under rotation conditions matured faster, survived better, differentiated to functional neurons that stained positively for mature neuronal markers, and fired action potentials similar to the statically cultured neurons. This report thus provides a technique for the scalable production of neurons from ES and iPS cells and we suggest that rotation culture procedure can be a routine technique for stem cell neural and neuronal differentiation.
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Affiliation(s)
- Osama Mohamad
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Shan Ping Yu
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Dongdong Chen
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Molly Ogle
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Mingke Song
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Ling Wei
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA.
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81
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Zhdanov AV, Dmitriev RI, Hynes J, Papkovsky DB. Kinetic Analysis of Local Oxygenation and Respiratory Responses of Mammalian Cells Using Intracellular Oxygen-Sensitive Probes and Time-Resolved Fluorometry. Methods Enzymol 2014; 542:183-207. [DOI: 10.1016/b978-0-12-416618-9.00010-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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82
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Liu X, Ye R, Yan T, Yu SP, Wei L, Xu G, Fan X, Jiang Y, Stetler RA, Liu G, Chen J. Cell based therapies for ischemic stroke: from basic science to bedside. Prog Neurobiol 2013; 115:92-115. [PMID: 24333397 DOI: 10.1016/j.pneurobio.2013.11.007] [Citation(s) in RCA: 146] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 11/11/2013] [Accepted: 11/26/2013] [Indexed: 12/20/2022]
Abstract
Cell therapy is emerging as a viable therapy to restore neurological function after stroke. Many types of stem/progenitor cells from different sources have been explored for their feasibility and efficacy for the treatment of stroke. Transplanted cells not only have the potential to replace the lost circuitry, but also produce growth and trophic factors, or stimulate the release of such factors from host brain cells, thereby enhancing endogenous brain repair processes. Although stem/progenitor cells have shown a promising role in ischemic stroke in experimental studies as well as initial clinical pilot studies, cellular therapy is still at an early stage in humans. Many critical issues need to be addressed including the therapeutic time window, cell type selection, delivery route, and in vivo monitoring of their migration pattern. This review attempts to provide a comprehensive synopsis of preclinical evidence and clinical experience of various donor cell types, their restorative mechanisms, delivery routes, imaging strategies, future prospects and challenges for translating cell therapies as a neurorestorative regimen in clinical applications.
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Affiliation(s)
- Xinfeng Liu
- Department of Neurology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China.
| | - Ruidong Ye
- Department of Neurology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Tao Yan
- Department of Neurology, Henry Ford Hospital, Detroit, MI, USA; Department of Neurology, Tianjin General Hospital, Tianjin University School of Medicine, Tianjin, China
| | - Shan Ping Yu
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA, USA
| | - Ling Wei
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA, USA
| | - Gelin Xu
- Department of Neurology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Xinying Fan
- Department of Neurology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Yongjun Jiang
- Department of Neurology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - R Anne Stetler
- Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - George Liu
- Institute of Cardiovascular Sciences, Peking University Health Science Center, Beijing, China
| | - Jieli Chen
- Department of Neurology, Henry Ford Hospital, Detroit, MI, USA.
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83
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Hsiao ST, Dilley RJ, Dusting GJ, Lim SY. Ischemic preconditioning for cell-based therapy and tissue engineering. Pharmacol Ther 2013; 142:141-53. [PMID: 24321597 DOI: 10.1016/j.pharmthera.2013.12.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 12/02/2013] [Indexed: 01/07/2023]
Abstract
Cell- and tissue-based therapies are innovative strategies to repair and regenerate injured hearts. Despite major advances achieved in optimizing these strategies in terms of cell source and delivery method, the clinical outcome of cell-based therapy remains unsatisfactory. The non-genetic approach of ischemic/hypoxic preconditioning to enhance cell- and tissue-based therapies has received much attention in recent years due to its non-invasive drug-free application. Here we discuss the current development of hypoxic/ischemic preconditioning to enhance stem cell-based cardiac repair and regeneration.
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Affiliation(s)
- Sarah T Hsiao
- Department of Cardiovascular Science, University of Sheffield, United Kingdom
| | - Rodney J Dilley
- Ear Science Institute Australia and Ear Sciences Centre, School of Surgery, University of Western Australia, Nedlands, Western Australia, Australia
| | - Gregory J Dusting
- Centre for Eye Research Australia and Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia; Department of Ophthalmology, University of Melbourne, East Melbourne, Victoria, Australia; Department of Surgery, University of Melbourne, Fitzroy, Victoria, Australia; O'Brien Institute, Fitzroy, Victoria, Australia
| | - Shiang Y Lim
- Department of Surgery, University of Melbourne, Fitzroy, Victoria, Australia; O'Brien Institute, Fitzroy, Victoria, Australia.
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84
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Song M, Mohamad O, Gu X, Wei L, Yu SP. Restoration of Intracortical and Thalamocortical Circuits after Transplantation of Bone Marrow Mesenchymal Stem Cells into the Ischemic Brain of Mice. Cell Transplant 2013; 22:2001-15. [DOI: 10.3727/096368912x657909] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Transplantation of bone marrow mesenchymal stem cells (BMSCs) provides a promising regenerative medicine for stroke. Whether BMSC therapy could repair ischemia-damaged neuronal circuits and recover electrophysiological activity has largely been unknown. To address this issue, BMSCs were implanted into the ischemic barrel cortex of adult mice 1 and 7 days after focal barrel cortex stroke. Two days after the first transplantation (3 days after stroke), the infarct volume determined by TTC staining was significantly smaller in BMSC-treated compared to vehicle-treated stroke mice. The behavioral corner test showed better long-term recovery of sensorimotor function in BMSC-treated mice. Six weeks poststroke, thalamocortical slices were prepared and neuronal circuit activity in the peri-infarct region of the barrel cortex was determined by extracellular recordings of evoked field potentials. In BMSC-transplanted brain slices, the ischemia-disrupted intracortical activity from layer 4 to layer 2/3 was noticeably recovered, and the thalamocortical circuit connection was also partially restored. In contrast, much less and slower recovery was seen in control animals of barrel cortex stroke. Immunohistochemical staining disclosed that the density of neurons, axons, and blood vessels in the peri-infarct region was significantly higher in BMSC-treated mice, accompanied with enhanced local blood flow recovery. Western blotting showed that BMSC treatment increased the expression of stromal cell-derived factor-1 (SDF-1), vascular endothelial growth factor (VEGF), and brain-derived neurotrophic factor (BDNF) in the peri-infarct region. Moreover, the expression of the axonal growth associated protein-43 (GAP-43) was markedly increased, whereas the axonal growth inhibiting proteins ROCK II and NG2 were suppressed in the BMSC-treated brains. BMSC transplantation also promoted directional migration and survival of doublecortin (DCX)-positive neuroblasts in the peri-infarct region. The present investigation thus provides novel evidence that BMSC transplantation has the potential to repair the ischemia-damaged neural networks and restore lost neuronal connections. The recovered circuit activity likely contributes to the improved sensorimotor function after focal ischemic stroke and BMSC transplantation.
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Affiliation(s)
- Mingke Song
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA, USA
| | - Osama Mohamad
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA, USA
| | - Xiaohuan Gu
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA, USA
| | - Ling Wei
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA, USA
| | - Shan Ping Yu
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA, USA
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85
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Liu M, Liu N, Zang R, Li Y, Yang ST. Engineering stem cell niches in bioreactors. World J Stem Cells 2013; 5:124-35. [PMID: 24179601 PMCID: PMC3812517 DOI: 10.4252/wjsc.v5.i4.124] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 06/05/2013] [Accepted: 07/04/2013] [Indexed: 02/06/2023] Open
Abstract
Stem cells, including embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells and amniotic fluid stem cells have the potential to be expanded and differentiated into various cell types in the body. Efficient differentiation of stem cells with the desired tissue-specific function is critical for stem cell-based cell therapy, tissue engineering, drug discovery and disease modeling. Bioreactors provide a great platform to regulate the stem cell microenvironment, known as "niches", to impact stem cell fate decision. The niche factors include the regulatory factors such as oxygen, extracellular matrix (synthetic and decellularized), paracrine/autocrine signaling and physical forces (i.e., mechanical force, electrical force and flow shear). The use of novel bioreactors with precise control and recapitulation of niche factors through modulating reactor operation parameters can enable efficient stem cell expansion and differentiation. Recently, the development of microfluidic devices and microbioreactors also provides powerful tools to manipulate the stem cell microenvironment by adjusting flow rate and cytokine gradients. In general, bioreactor engineering can be used to better modulate stem cell niches critical for stem cell expansion, differentiation and applications as novel cell-based biomedicines. This paper reviews important factors that can be more precisely controlled in bioreactors and their effects on stem cell engineering.
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Affiliation(s)
- Meimei Liu
- Meimei Liu, Ning Liu, Ru Zang, Shang-Tian Yang, William G Lowrie Department of Chemical and Biomolecular Engineering, Ohio State University, Columbus, OH 43210, United States
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86
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Chung DJ, Wong A, Hayashi K, Yellowley CE. Effect of hypoxia on generation of neurospheres from adipose tissue-derived canine mesenchymal stromal cells. Vet J 2013; 199:123-30. [PMID: 24252224 DOI: 10.1016/j.tvjl.2013.10.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Revised: 10/16/2013] [Accepted: 10/18/2013] [Indexed: 12/29/2022]
Abstract
Adipose tissue-derived mesenchymal stromal cells (AT-MSCs) are good candidates for cell therapy due to the accessibility of fat tissue and the abundance of AT-MSCs therein. Neurospheres are free-floating spherical condensations of cells with neural stem/progenitor cell (NSPC) characteristics that can be derived from AT-MSCs. The aims of this study were to examine the influence of oxygen (O2) tension on generation of neurospheres from canine AT-MSCs (AT-cMSCs) and to develop a hypoxic cell culture system to enhance the survival and therapeutic benefit of generated neurospheres. AT-cMSCs were cultured under varying oxygen tensions (1%, 5% and 21%) in a neurosphere culture system. Neurosphere number and area were evaluated and NSPC markers were quantified using real-time quantitative PCR (qPCR). Effects of oxygen on neurosphere expression of hypoxia inducible factor 1, α subunit (HIF1A) and its target genes, erythropoietin receptor (EPOR), chemokine (C-X-C motif) receptor 4 (CXCR4) and vascular endothelial growth factor (VEGF), were quantified by qPCR. Neural differentiation potential was evaluated in 21% O2 by cell morphology and qPCR. Neurospheres were successfully generated from AT-cMSCs at all O2 tensions. Expression of nestin mRNA (NES) was significantly increased after neurosphere culture and was significantly higher in 1% O2 compared to 5% and 21% O2. Neurospheres cultured in 1% O2 had significantly increased levels of VEGF and EPOR. There was a significant increase in CXCR4 expression in neurospheres generated at all O2 tensions. Neurosphere culture under hypoxia had no negative effect on subsequent neural differentiation. This study suggests that generation of neurospheres under hypoxia could be beneficial when considering these cells for neurological cell therapies.
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Affiliation(s)
- D J Chung
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - A Wong
- Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - K Hayashi
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - C E Yellowley
- Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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87
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Drury-Stewart D, Song M, Mohamad O, Guo Y, Gu X, Chen D, Wei L. Highly efficient differentiation of neural precursors from human embryonic stem cells and benefits of transplantation after ischemic stroke in mice. Stem Cell Res Ther 2013; 4:93. [PMID: 23928330 PMCID: PMC3854684 DOI: 10.1186/scrt292] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 07/26/2013] [Indexed: 02/07/2023] Open
Abstract
Introduction Ischemic stroke is a leading cause of death and disability, but treatment options are severely limited. Cell therapy offers an attractive strategy for regenerating lost tissues and enhancing the endogenous healing process. In this study, we investigated the use of human embryonic stem cell-derived neural precursors as a cell therapy in a murine stroke model. Methods Neural precursors were derived from human embryonic stem cells by using a fully adherent SMAD inhibition protocol employing small molecules. The efficiency of neural induction and the ability of these cells to further differentiate into neurons were assessed by using immunocytochemistry. Whole-cell patch-clamp recording was used to demonstrate the electrophysiological activity of human embryonic stem cell-derived neurons. Neural precursors were transplanted into the core and penumbra regions of a focal ischemic stroke in the barrel cortex of mice. Animals received injections of bromodeoxyuridine to track regeneration. Neural differentiation of the transplanted cells and regenerative markers were measured by using immunohistochemistry. The adhesive removal test was used to determine functional improvement after stroke and intervention. Results After 11 days of neural induction by using the small-molecule protocol, over 95% of human embryonic stem-derived cells expressed at least one neural marker. Further in vitro differentiation yielded cells that stained for mature neuronal markers and exhibited high-amplitude, repetitive action potentials in response to depolarization. Neuronal differentiation also occurred after transplantation into the ischemic cortex. A greater level of bromodeoxyuridine co-localization with neurons was observed in the penumbra region of animals receiving cell transplantation. Transplantation also improved sensory recovery in transplant animals over that in control animals. Conclusions Human embryonic stem cell-derived neural precursors derived by using a highly efficient small-molecule SMAD inhibition protocol can differentiate into electrophysiologically functional neurons in vitro. These cells also differentiate into neurons in vivo, enhance regenerative activities, and improve sensory recovery after ischemic stroke.
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Gao J, Thonhoff JR, Dunn TJ, Wu P. Lipoic acid enhances survival of transplanted neural stem cells by reducing transplantation-associated injury. JOURNAL OF NEURORESTORATOLOGY 2013; 1:1-12. [PMID: 35663360 PMCID: PMC9162033 DOI: 10.2147/jn.s43745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The efficacy of stem cell-based therapy for neurological diseases depends highly on cell survival post-transplantation. One of the key factors affecting cell survival is the grafting procedure. The current study aims to determine whether needle insertion into intact rat spinal cords creates a hypoxic environment that is prone to lipid peroxidation damage upon reperfusion, and whether an antioxidant protects human neural stem cells (hNSCs) both in vitro and post-transplantation into rat spinal cords. We show here that a single needle injection creates a hypoxic environment within the rat spinal cord that peaks at approximately 12 hours before reperfusion occurs. Lipid peroxidation damage at the transplantation site is evident by 48 hours post-needle insertion. In an in vitro model, hypoxia-reperfusion results in apoptotic death of hNSCs. Pretreatment with the antioxidant, α-lipoic acid, protects hNSCs against hypoxia-reperfusion injury and oxidative stress-mediated cell death. Increasing glutathione, but not Akt signaling, contributes to the protective effect of lipoic acid. Pretreating hNSCs with lipoic acid also increases the cell survival rate 1 month post-transplantation. Further investigation is warranted to develop improved techniques to maximize the survival of transplanted stem cells.
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Affiliation(s)
- Junling Gao
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Jason R Thonhoff
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX, USA
- Department of Neurology, The Methodist Hospital, Houston, TX, USA
| | - Tiffany J Dunn
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Ping Wu
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX, USA
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89
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Kim J, Sachdev P, Sidhu K. Alginate microcapsule as a 3D platform for the efficient differentiation of human embryonic stem cells to dopamine neurons. Stem Cell Res 2013; 11:978-89. [PMID: 23900167 DOI: 10.1016/j.scr.2013.06.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 05/26/2013] [Accepted: 06/14/2013] [Indexed: 01/17/2023] Open
Abstract
Human embryonic stem cells (hESCs) are emerging as an attractive alternative source for cell replacement therapy since the cells can be expanded in culture indefinitely and differentiated into any cell types in the body. In order to optimize cell-to-cell interaction, cell proliferation and differentiation into specific lineages as well as tissue organization, it is important to provide a microenvironment for the hESCs which mimics the stem cell niche. One approach is to provide a three-dimensional (3D) environment such as encapsulation. We present an approach to culture and differentiate hESCs into midbrain dopamine (mdDA) neurons in a 3D microenvironment using alginate microcapsules for the first time. A detailed gene and protein expression analysis during neuronal differentiation showed an increased gene and protein expression of various specific DA neuronal markers, particularly tyrosine hydroxylase (TH) by >100 folds after 2 weeks and at least 50% higher expression after 4 weeks respectively, compared to cells differentiated under conventional two-dimensional (2D) platform. The encapsulated TH(+) cells co-expressed mdDA neuronal markers, forkhead box protein A-2 (FOXA2) and pituitary homeobox-3 (PITX3) after 4 weeks and secreted approximately 60pg/ml/10(6) cells higher DA level when induced. We propose that the 3D platform facilitated an early onset of DA neuronal generation compared to that with conventional 2D system which also secretes more DA under potassium-induction. It is a very useful model to study the proliferation and directed differentiation of hESCs to various lineages, particularly to mdDA neurons. This 3D system also allows the separation of feeder cells from hESCs during the process of differentiation and also has potential for immune-isolation during transplantation studies.
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Affiliation(s)
- Jaemin Kim
- Stem Cell Lab, Faculty of Medicine, School of Psychiatry, University of New South Wales, Australia.
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90
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Mohamad O, Drury-Stewart D, Song M, Faulkner B, Chen D, Yu SP, Wei L. Vector-free and transgene-free human iPS cells differentiate into functional neurons and enhance functional recovery after ischemic stroke in mice. PLoS One 2013; 8:e64160. [PMID: 23717557 PMCID: PMC3662762 DOI: 10.1371/journal.pone.0064160] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Accepted: 04/11/2013] [Indexed: 02/07/2023] Open
Abstract
Stroke is a leading cause of human death and disability in the adult population in the United States and around the world. While stroke treatment is limited, stem cell transplantation has emerged as a promising regenerative therapy to replace or repair damaged tissues and enhance functional recovery after stroke. Recently, the creation of induced pluripotent stem (iPS) cells through reprogramming of somatic cells has revolutionized cell therapy by providing an unlimited source of autologous cells for transplantation. In addition, the creation of vector-free and transgene-free human iPS (hiPS) cells provides a new generation of stem cells with a reduced risk of tumor formation that was associated with the random integration of viral vectors seen with previous techniques. However, the potential use of these cells in the treatment of ischemic stroke has not been explored. In the present investigation, we examined the neuronal differentiation of vector-free and transgene-free hiPS cells and the transplantation of hiPS cell-derived neural progenitor cells (hiPS-NPCs) in an ischemic stroke model in mice. Vector-free hiPS cells were maintained in feeder-free and serum-free conditions and differentiated into functional neurons in vitro using a newly developed differentiation protocol. Twenty eight days after transplantation in stroke mice, hiPS-NPCs showed mature neuronal markers in vivo. No tumor formation was seen up to 12 months after transplantation. Transplantation of hiPS-NPCs restored neurovascular coupling, increased trophic support and promoted behavioral recovery after stroke. These data suggest that using vector-free and transgene-free hiPS cells in stem cell therapy are safe and efficacious in enhancing recovery after focal ischemic stroke in mice.
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Affiliation(s)
- Osama Mohamad
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Danielle Drury-Stewart
- Department of Biomedical Engineering, Georgia Tech Institute, Atlanta, Georgia, United States of America
| | - Mingke Song
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Ben Faulkner
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Dongdong Chen
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Shan Ping Yu
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Ling Wei
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, Georgia, United States of America
- * E-mail:
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91
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Haines B, Mao X, Xie L, Spusta S, Zeng X, Jin K, Greenberg DA. Neuroglobin expression in neurogenesis. Neurosci Lett 2013; 549:3-6. [PMID: 23643985 DOI: 10.1016/j.neulet.2013.04.039] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 04/11/2013] [Accepted: 04/12/2013] [Indexed: 01/15/2023]
Abstract
Neuroglobin is a hypoxia-inducible, neuroprotective protein related to myoglobin and hemoglobin, but little is known about its neurodevelopmental expression or function. To begin to explore these issues, we measured neuroglobin protein expression during neuronal differentiation of human embryonic stem cells in vitro and in the neurogenic subventricular zone of adult rats in vivo. Neuroglobin protein expression was barely detectable by western blotting in human embryonic stem cells, but was readily demonstrable in neural stem cells, and was further induced upon differentiation to neurons. In the adult subventricular zone, neuroglobin expression coincided with that of the neuronal lineage marker doublecortin, but not with vimentin or glial fibrillary acidic protein. These findings suggest that neuroglobin is expressed early in the course of neuronal differentiation and may, therefore, have a role in neurodevelopment.
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Affiliation(s)
- Bryan Haines
- Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945, USA
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92
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Chocyk A, Bobula B, Dudys D, Przyborowska A, Majcher-Maślanka I, Hess G, Wędzony K. Early-life stress affects the structural and functional plasticity of the medial prefrontal cortex in adolescent rats. Eur J Neurosci 2013; 38:2089-107. [PMID: 23581639 DOI: 10.1111/ejn.12208] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Accepted: 03/03/2013] [Indexed: 02/06/2023]
Abstract
Early life experiences are crucial factors that shape brain development and function due to their ability to induce structural and functional plasticity. Among these experiences, early-life stress (ELS) is known to interfere with brain development and maturation, increasing the risk of future psychopathologies, including depression, anxiety, and personality disorders. Moreover, ELS may contribute to the emergence of these psychopathologies during adolescence. In this present study, we investigated the effects of ELS, in the form of maternal separation (MS), on the structural and functional plasticity of the medial prefrontal cortex (mPFC) and anxiety-like behavior in adolescent male rats. We found that the MS procedure resulted in disturbances in mother-pup interactions that lasted until weaning and were most strongly demonstrated by increases in nursing behavior. Moreover, MS caused atrophy of the basal dendritic tree and reduced spine density on both the apical and basal dendrites in layer II/III pyramidal neurons of the mPFC. The structural changes were accompanied by an impairment of long-term potentiation processes and increased expression of key proteins, specifically glutamate receptor 1, glutamate receptor 2, postsynaptic density protein 95, αCa(2+) /calmodulin-dependent protein kinase II and αCa(2+)/calmodulin-dependent protein kinase II phosphorylated at residue Thr305, that are engaged in long-term potentiation induction and maintenance in the mPFC. We also found that the MS animals were more anxious in the light/dark exploration test. The results of this study indicate that ELS has a significant impact on the structural and functional plasticity of the mPFC in adolescents. ELS-induced adaptive plasticity may underlie the pathomechanisms of some early-onset psychopathologies observed in adolescents.
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Affiliation(s)
- Agnieszka Chocyk
- Laboratory of Pharmacology and Brain Biostructure, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland.
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93
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Ohnuki Y, Kurosawa H. Effects of hanging drop culture conditions on embryoid body formation and neuronal cell differentiation using mouse embryonic stem cells: optimization of culture conditions for the formation of well-controlled embryoid bodies. J Biosci Bioeng 2012; 115:571-4. [PMID: 23276518 DOI: 10.1016/j.jbiosc.2012.11.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Revised: 11/08/2012] [Accepted: 11/20/2012] [Indexed: 01/18/2023]
Abstract
Hanging drop (HD) cultures were carried out with a drop volume of either 20 or 30 μl. An incubation period of 3 days was determined to be appropriate for the formation of well-controlled embryoid bodies (EBs), and the initial cell number was identified as the most critical factor in the growth and neuronal cell differentiation of EBs.
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Affiliation(s)
- Yoshitsugu Ohnuki
- Division of Medicine and Engineering Science, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511, Japan
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94
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Lei XH, Zhao D, Li YL, Li XF, Sun X, Du WZ, Sun Y, Hao ZF, Xin SY, Liu C, Zhang ZR, Jiang CL. Pifithrin-α enhances the survival of transplanted neural stem cells in stroke rats by inhibiting p53 nuclear translocation. CNS Neurosci Ther 2012; 19:109-16. [PMID: 23253187 DOI: 10.1111/cns.12045] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 11/05/2012] [Accepted: 11/09/2012] [Indexed: 12/16/2022] Open
Abstract
AIMS To examine a novel strategy to enhance the survival of grafted neural stem cells (NSCs) in stroke model. METHODS Using a cell counting kit-8 (CCK-8) and TUNEL assay to test the protective effects of p53 inhibitor, pifithrin-α (PFT-α), on oxygen glucose deprivation (OGD) in NSCs. We compared the effects of vehicle + NSCs and FFT-α + NSCs on the efficacy of transplantation in stroke rat model using behavioral analysis, immunohistochemistry, etc. RESULTS Pifithrin-α increased viability and decreased apoptosis in NSCs after OGD in vitro. By in vivo studies, we showed that the best recovery of neurological function in the stroke rats and the maximum survival of grafted NSCs were found in the PFT-α + NSCs group. Twelve hours after cell transplantation, p53 was localized to the nuclei of grafted NSCs in the vehicle + NSCs group but was primarily localized to the cytoplasm in the PFT-α + NSCs group. The p53-upregulated modulator of apoptosis (PUMA) was highly expressed among the grafted cells in the vehicle + NSCs group compared with that in the PFT-α + NSCs group. CONCLUSION Our results indicate that PFT-α enhances the survival of grafted NSCs through the inhibition of p53 translocation into the nucleus.
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Affiliation(s)
- Xu-Hui Lei
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, China
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95
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Pellegrini L, Bennis Y, Guillet B, Velly L, Bruder N, Pisano P. [Cell therapy for stroke: from myth to reality]. Rev Neurol (Paris) 2012; 169:291-306. [PMID: 23246427 DOI: 10.1016/j.neurol.2012.08.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 07/13/2012] [Accepted: 08/09/2012] [Indexed: 01/01/2023]
Abstract
INTRODUCTION Stroke is one of the leading causes of death and disability worldwide. Intravenous recombinant tissue plasminogen activator is the only available therapy for acute ischemic stroke, but its use is limited by a narrow therapeutic window and cannot stimulate endogenous repair and regeneration of damaged brain tissue. Stem cell-based approaches hold much promise as potential novel treatments to restore neurological function after stroke. STATE OF THE ART In this review, we summarize data from preclinical and clinical studies to investigate the potential application of stem cell therapies for treatment of stroke. Stem cells have been proposed as a potential source of new cells to replace those lost due to central nervous system injury, as well as a source of trophic molecules to minimize damage and promote recovery. Various stem cells from multiple sources can generate neural cells that survive and form synaptic connections after transplantation in the stroke-injured brain. Stem cells also exhibit neurorevitalizing properties that may ameliorate neurological deficits through stimulation of neurogenesis, angiogenesis and inhibition of inflammation. PERSPECTIVES/CONCLUSION Performed in stroke, cell therapy would decrease brain damage and reduce functional deficits. After the damage has been done, it would still improve neurological functions by activating endogenous repair. Nevertheless, many questions raised by experimental studies particularly related to long-term safety and technical details of cell preparation and administration must be resolved before wider clinical use.
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Affiliation(s)
- L Pellegrini
- Service d'anesthésie-réanimation 1, CHU de la Timone, Assistance publique-Hôpitaux de Marseille, 264, rue Saint-Pierre, 13385 Marseille cedex 5, France.
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96
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Paulsen BDS, da Silveira MS, Galina A, Rehen SK. Pluripotent stem cells as a model to study oxygen metabolism in neurogenesis and neurodevelopmental disorders. Arch Biochem Biophys 2012; 534:3-10. [PMID: 23111185 DOI: 10.1016/j.abb.2012.10.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Revised: 09/14/2012] [Accepted: 10/17/2012] [Indexed: 01/19/2023]
Abstract
Reactive oxygen species (ROS) and oxygen (O2) have been implicated in neurogenesis and self-renewal of neural progenitor cells (NPCs). On the other hand, oxidative unbalance, either by an impairment of antioxidant defenses or by an intensified production of ROS, is increasingly related to risk factors of neurodevelopmental disorders, such as schizophrenia. In this scenario, human induced pluripotent stem cells (hiPSCs) emerged as an interesting platform for the study of cellular and molecular aspects of this mental disorder, by complementing other experimental models, with exclusive advantages such as the recapitulation of brain development. Herein we discuss the role of O2/ROS signaling for neuronal differentiation and how its unbalance could be related to neurodevelopmental disorders, such as schizophrenia. Identifying the role of O2/ROS in neurogenesis as well as tackling oxidative stress and its disturbances in schizophrenic patients' derived cells will provide an interesting opportunity for the study of neural stem cells differentiation and neurodevelopmental disorders.
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Affiliation(s)
- Bruna da Silveira Paulsen
- Laboratório Nacional de Células-Tronco Embrionárias, Instituto de Ciências Biomédicas, UFRJ, Rio de Janeiro RJ 21941-913, Brazil
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97
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Mahan VL, Zurakowski D, Otterbein LE, Pigula FA. Inhaled carbon monoxide provides cerebral cytoprotection in pigs. PLoS One 2012; 7:e41982. [PMID: 22879904 PMCID: PMC3413707 DOI: 10.1371/journal.pone.0041982] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Accepted: 06/27/2012] [Indexed: 11/18/2022] Open
Abstract
Carbon monoxide (CO) at low concentrations imparts protective effects in numerous preclinical small animal models of brain injury. Evidence of protection in large animal models of cerebral injury, however, has not been tested. Neurologic deficits following open heart surgery are likely related in part to ischemia reperfusion injury that occurs during cardiopulmonary bypass surgery. Using a model of deep hypothermic circulatory arrest (DHCA) in piglets, we evaluated the effects of CO to reduce cerebral injury. DHCA and cardiopulmonary bypass (CPB) induced significant alterations in metabolic demands, including a decrease in the oxygen/glucose index (OGI), an increase in lactate/glucose index (LGI) and a rise in cerebral blood pressure that ultimately resulted in increased cell death in the neocortex and hippocampus that was completely abrogated in piglets preconditioned with a low, safe dose of CO. Moreover CO-treated animals maintained normal, pre-CPB OGI and LGI and corresponding cerebral sinus pressures with no change in systemic hemodynamics or metabolic intermediates. Collectively, our data demonstrate that inhaled CO may be beneficial in preventing cerebral injury resulting from DHCA and offer important therapeutic options in newborns undergoing DHCA for open heart surgery.
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Affiliation(s)
- Vicki L Mahan
- Department of Surgery, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States of America.
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98
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Lee SW, Jeong HK, Lee JY, Yang J, Lee EJ, Kim SY, Youn SW, Lee J, Kim WJ, Kim KW, Lim JM, Park JW, Park YB, Kim HS. Hypoxic priming of mESCs accelerates vascular-lineage differentiation through HIF1-mediated inverse regulation of Oct4 and VEGF. EMBO Mol Med 2012; 4:924-38. [PMID: 22821840 PMCID: PMC3491825 DOI: 10.1002/emmm.201101107] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Revised: 05/15/2012] [Accepted: 05/18/2012] [Indexed: 12/21/2022] Open
Abstract
Hypoxic microenvironment plays an important role in determining stem cell fates. However, it is controversial to which direction between self-renewal and differentiation the hypoxia drives the stem cells. Here, we investigated whether a short exposure to hypoxia (termed ‘hypoxic-priming’) efficiently directed and promoted mouse embryonic stem cells (mESCs) to differentiate into vascular-lineage. During spontaneous differentiation of embryoid bodies (EBs), hypoxic region was observed inside EB spheroids even under normoxic conditions. Indeed, hypoxia-primed EBs more efficiently differentiated into cells of vascular-lineage, than normoxic EBs did. We found that hypoxia suppressed Oct4 expression via direct binding of HIF-1 to reverse hypoxia-responsive elements (rHREs) in the Oct4 promoter. Furthermore, vascular endothelial growth factor (VEGF) was highly upregulated in hypoxia-primed EBs, which differentiated towards endothelial cells in the absence of exogenous VEGF. Interestingly, this differentiation was abolished by the HIF-1 or VEGF blocking. In vivo transplantation of hypoxia-primed EBs into mice ischemic limb elicited enhanced vessel differentiation. Collectively, our findings identify that hypoxia enhanced ESC differentiation by HIF-1-mediated inverse regulation of Oct4 and VEGF, which is a novel pathway to promote vascular-lineage differentiation.
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Affiliation(s)
- Sae-Won Lee
- Department of Internal Medicine, Innovative Research Institute for Cell Therapy, Seoul National University Hospital, Korea
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99
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Abstract
Although the adult human brain has a small number of neural stem cells, they are insufficient to repair the damaged brain to achieve significant functional recovery for neurodegenerative diseases and stroke. Stem cell therapy, by either enhancing endogenous neurogenesis, or transplanting stem cells, has been regarded as a promising solution. However, the harsh environment of the diseased brain posts a severe threat to the survival and correct differentiation of those new stem cells. Hormesis (or preconditioning, stress adaptation) is an adaptation mechanism by which cells or organisms are potentiated to survive an otherwise lethal condition, such as the harsh oxidative stress in the stroke brain. Stem cells treated by low levels of chemical, physical, or pharmacological stimuli have been shown to survive better in the neurodegenerative brain. Thus combining hormesis and stem cell therapy might improve the outcome for treatment of these diseases. In addition, since the cell death patterns and their underlying molecular mechanism may vary in different neurodegenerative diseases, even in different progression stages of the same disease, it is essential to design a suitable and optimum hormetic strategy that is tailored to the individual patient.
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Affiliation(s)
- Guanghu Wang
- Institute of Molecular Medicine and Genetics, Medical College of Georgia, Georgia Health Sciences University
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100
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Stem cells as a tool for breast imaging. JOURNAL OF ONCOLOGY 2012; 2012:814014. [PMID: 22848220 PMCID: PMC3405672 DOI: 10.1155/2012/814014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Accepted: 06/18/2012] [Indexed: 12/16/2022]
Abstract
Stem cells are a scientific field of interest due to their therapeutic potential. There are different groups, depending on the differentiation state. We can find lonely stem cells, but generally they distribute in niches. Stem cells don't survive forever. They are affected for senescence. Cancer stem cells are best defined functionally, as a subpopulation of tumor cells that can enrich for tumorigenic property and can regenerate heterogeneity of the original tumor. Circulating tumor cells are cells that have detached from a primary tumor and circulate in the bloodstream. They may constitute seeds for subsequent growth of additional tumors (metastasis) in different tissues. Advances in molecular imaging have allowed a deeper understanding of the in vivo behavior of stem cells and have proven to be indispensable in preclinical and clinical studies. One of the first imaging modalities for monitoring pluripotent stem cells in vivo, magnetic resonance imaging (MRI) offers high spatial and temporal resolution to obtain detailed morphological and functional information. Advantages of radioscintigraphic techniques include their picomolar sensitivity, good tissue penetration, and translation to clinical applications. Radionuclide imaging is the sole direct labeling technique used thus far in human studies, involving both autologous bone marrow derived and peripheral stem cells.
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