[Show abstract][Hide abstract] ABSTRACT: Purpose: Recent developments in the field of cell therapy have led to a renewed interest in treatment of acute kidney injury (AKI). However, the early death of transplanted mesenchymal stem cells (MSCs) in stressful microenvironment of a recipient tissue is a major problem with this kind of treatment. The objective of this study was to determine whether overexpression of a cytoprotective factor, nuclear factor erythroid-2 related factor 2 (Nrf2), in MSCs could protect rats against AKI.
Methods: The Nrf2 was overexpressed in MSCs by recombinant adenoviruses, and the MSCs were implanted to rats suffering from cisplatin-induced AKI.
Results: The obtained results showed that transplantation with the engineered MSCs ameliorates cisplatin-induced AKI. Morphologic features of the investigated kidneys showed that transplantation with the MSCs in which Nrf2 had been overexpressed significantly improved the complications of AKI.
Conclusion: These findings suggested that the engineered MSCs might be a good candidate to be further evaluated in clinical trials. However, detailed studies must be performed to investigate the possible carcinogenic effect of Nrf2 overexpression.
[Show abstract][Hide abstract] ABSTRACT: Objective Wharton's jelly (WJ), an appropriate source of mesenchymal stem cells (MSCs), has been shown to have a wide array of therapeutic applications. However, the WJ-derived MSCs are very heterogeneous and have limited expression of pluripotency markers. Hence, improvement of their culture condition would promote the efficiency of WJ-MSCs. This study aims to employ a simple method of cultivation to obtain WJ-MSCs which express more pluripotency markers. Methods CD105(+) cells were separated by magnetic-associated (activated) cell sorting from umbilical cord mucous tissue. CD105(+) cells were added to Methocult medium diluted in α-minimum essential medium (α-MEM) and seeded in poly(2-hydroxyethyl methacrylate) (poly-HEMA)-coated plates for suspension culture preparation. Differentiation capacity of isolated cells was evaluated in the presence of differentiation-inducing media. The expression of pluripotency markers such as Oct3/4, Nanog, and Sox2 was also analyzed by RT-PCR and western blot techniques. Moreover, immunocytochemistry was performed to detect α-SMA protein. Results WJ-MSCs grew homogeneously and formed colonies when cultured under suspension culture conditions (Non-adhesive WJ-MSCs). They maintained their growth ability in both adherent and suspension cultures for several passages. Non-adhesive WJ-MSCs expressed Oct3/4, Nanog, and Sox2 both at transcriptional and translational levels in comparison to those cultured in conventional adherent cultures. They also expressed alpha-smooth muscle actin (antigene) (α-SMA) protein. Discussion In this study, we isolated WJ-MSCs using a slightly modified culture condition. Our simple non-genetic method resulted in a homogeneous population of WJ-MSCs, which highly expressed pluripotency markers. Conclusion In the future, more multipotent WJ-MSCs can be harnessed as a non-embryonic source of MSCs in MSC-based cell therapy.
[Show abstract][Hide abstract] ABSTRACT: Conditioned medium of mesenchymal stem cells (MSCs) is now being used for its cytoprotective effects, especially when the cells are equipped with cytoprotective factors to strengthen them against unfavorable microenvironments. Overexpression of Lcn2 in MSCs mimics in vivo kidney injury. Hence, unraveling how Lcn2-engineered MSCs affect kidney cells has been investigated. Cisplatin treated HK-2 or HEK293 kidney cells were co-cultivated with Lcn2 overexpressing MSCs in upper and lower chambers of transwell plates. Proliferation, apoptosis, and expression of growth factors and cytokines were assessed in the kidney cells. Co-cultivation with the MSCs-Lcn2 not only inhibited cisplatin-induced cytotoxicity in the HK-2 and HEK293 cells, but increased proliferation rate, prevented cisplatin-induced apoptosis, and increased expression of growth factors and the amount of antioxidants in the kidney cells. Thus Lcn2-engineered MSCs can ameliorate and repair injured kidney cells in vitro, which strongly suggests there are beneficial effects of the MSCs-Lcn2 in cell therapy of kidney injury.
Cell Biology International 07/2014; · 1.64 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Myocardial infarction (MI) is the leading cause of death worldwide. Various therapeutic strategies have been
introduced for MI treatment. In recent years, interest in utilizing mesenchymal stem cells (MSCs) for MI therapy has
increased. In fact, the use of MSCs for MI treatment, known as cellular cardiomyoplasty, is in the clinical trial stage.
However, despite promising results, most MSCs die after transplantation as a result of exposure to various stresses.
Nuclear factor (erythroid-derived 2)-like 2 (Nrf2), a well-known cytoprotective transcription factor, protects MSCs
against some stresses. Over-expression of Nrf2 in MSCs decreases their apoptosis in vitro without any adverse
effects on their differentiation capacity. Therefore, we hypothesized that over-expression of Nrf2 in MSCs can
improve cellular cardiomyoplasty
[Show abstract][Hide abstract] ABSTRACT: Background Bacterial contamination of platelet products is the major infectious risk in blood transfusion medicine, which can result in life-threatening sepsis in recipient. Lipocalin 2 (Lcn2) is an iron-sequestering protein in the antibacterial innate immune response, which inhibit bacterial growth. This study was aimed to evaluate the antibacterial property of Lcn2 in preventing bacterial contamination of platelets. Methods Recombinant Lcn2 was expressed in a eukaryotic expression system and following purification and characterization of the recombinant Lcn2, its minimum inhibitory concentration was determined. Then, platelet concentrates were inoculated with various concentrations of Staphylococcus epidermidis, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, and Enterococcus faecalis, and the antibacterial effects of Lcn2 was evaluated at 20-24°C. Results Results revealed that Lcn2 effectively inhibited the growth of 1.5 × 10(4) CFU/ml S. epidermidis, P. aeruginosa, K. pneumoniae, E. coli, and E. faecalis at 40 ng/ml. At this concentration, Lcn2 also inhibited the growth of 1.5 × 10(3) CFU/ml Staphylococcus aureus and Proteus mirabilis. Conclusion Recombinant Lcn2 inhibited growth of a variety of platelet-contaminating bacteria. Therefore, supplementation of platelet concentrates with Lcn2 may reduce bacterial contamination.
[Show abstract][Hide abstract] ABSTRACT: Spermatogonial stem cells (SSCs) are the only cell type that can restore fertility to an infertile recipient following transplantation. Much effort has been made to develop a protocol for differentiating isolated SSCs in vitro. Recently, three-dimensional (3D) culture system has been introduced as an appropriate microenvironment for clonal expansion and differentiation of SSCs. This system provides structural support and multiple options for several manipulation such as addition of different cells. Somatic cells have a critical role in stimulating spermatogenesis. They provide complex cell to cell interaction, transport proteins and produce enzymes and regulatory factors. This study aimed to optimize the culture condition by adding somatic testicular cells to the collagen gel culture system in order to induce spermatogenesis progression.
In this experimental study, the disassociation of SSCs was performed by using a two-step enzymatic digestion of type I collagenase, hyaluronidase and DNase. Somatic testicular cells including Sertoli cells and peritubular cells were obtained after the second digestion. SSCs were isolated by Magnetic Activated Cell Sorting (MACS) using GDNF family receptor alpha-1 (Gfrα-1) antibody. Two experimental designs were investigated. 1. Gfrα-1 positive SSCs were cultured in a collagen solution. 2. Somatic testicular cells were added to the Gfrα-1 positive SSCs in a collagen solution. Spermatogenesis progression was determined after three weeks by staining of synaptonemal complex protein 3 (SCP3)-positive cells. Semi-quantitative Reverse Transcription PCR was undertaken for SCP3 as a meiotic marker and, Crem and Thyroid transcription factor-1 (TTF1) as post meiotic markers. For statistical analysis student t test was performed.
Testicular supporter cells increased the expression of meiotic and post meiotic markers and had a positive effect on extensive colony formation.
Collagen gel culture system supported by somatic testicular cells provides a microenvironment that mimics seminiferous epithelium and induces spermatogenesis in vitro.
[Show abstract][Hide abstract] 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.
Cell Stress and Chaperones 01/2014; · 2.48 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The regenerative potential of mesenchymal stem cells (MSCs) is impaired by cellular senescence, a multi factorial process that has various functions. However, pathways and molecules involved in senescence have not been fully identified. Lipocalin 2 (Lcn2) has been the subject of intensive research, due to its contribution to many physiological and pathophysiological conditions. The implication of Lcn2 has been reported in many conditions where senescence also occurs. In the present study, we evaluated the role of Lcn2 in the occurrence of senescence in human bone marrow-derived mesenchymal stem cells (hB-MSCs) under oxidative conditions. When hB-MSCs were genetically engineered to over-express Lcn2 (MSC-Lcn2) and exposed to H2O2, the proliferation rate of the cells increased. However, the number of colonies and the number of cells that made up each colony in both MSC-V and MSC-Lcn2 cells decreased compared to those cultivated under normal conditions. Our results revealed that over-expression of recombinant Lcn2 in hB-MSCs decreases senescence induced by H2O2 treatment. Senescent cells were observed in aged hB-MSCs; however, no alteration in the expression level of Lcn2 was detected compared to earlier passages. Finally, a higher amount of Lcn2 protein was detected in the plasma of the elderly than in young people. Our findings suggest that Lcn2 might restore the health and regeneration potential of MSCs by decreasing senescence.
Cell Stress and Chaperones 01/2014; · 2.48 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background: Increased mesenchymal stem cells (MSCs) survival after transplantation can improve their therapeutic potential. Therefore, manipulation of the MSCs with cytoprotective genes such as NF-E2 Related Factor-2 (NRF2) is important to improve cell therapy efficiency. The aim of this study was cloning and transient over-expression of the NRF2 gene in MSCs by adenoviral expression system.
Methods: NRF2 was isolated from MSCs and cloned into pENTR/TOPO/D vector by TOPO cloning reaction. NRF2 was translocated from pENTR/TOPO/D vector to adenoviral vector using the Gateway technology. The recombinant adenovirus vector was transformed into 293A cells to package recombinant adenovirus particles. Recombinant adenoviruses harboring NRF2 infected MSCs.
Results: NRF2 was successfully isolated, cloned and its accuracy was confirmed by Deoxyribonucleic acid (DNA) sequencing. NRF2 over-expression was evaluated. This over-expression by adenoviral expression system was transient.
Conclusion: NRF2 over-expression in MSCs with adenoviral expression system could be a valuable device because of its transient expression. Stable over-expression of genes in MSCs could not be permitted.
Journal of Kermanshah University of Medical Sciences. 07/2013; 17(5):273-286.
[Show abstract][Hide abstract] ABSTRACT: Abstract Spermatogonial stem cells (SSCs) represent a unique testicular cell type that has the capacity for proliferating, differentiating, and transmitting genetic information. This particular cell type is a strong focus of stem cell research, with isolation and maintenance of SSCs as an important issue. Therefore, we attempted to optimize SSCs handling and to analyze different media and feeder layers, such as adult and embryonic Sertoli cells. The expression patterns of SSC-specific proteins (α6 and β1 integrins, Stra8, and DAZL) and restoration of spermatogenesis were chosen as parameters to demonstrate the efficacy of the protocol. SSCs were isolated from testes of 3- to 6-day-old mice using a magnetic activated cell-sorting system and Thy-1 antibody. After enrichment, SSCs were cultured for 7 days with different media and feeder layers. Then, SSCs were transplanted to recipient mice. Culturing on adult and embryonic Sertoli cells and in the presence of different growth factors [glial cell line-derived neurotrophic factor (GDNF), GDNF family receptor α1 (GFR-α1), and basic fibroblast growth factor (bFGF) resulted in an undifferentiated SSC phenotype with typical stem cell characteristics observed in vivo. The established co-culture model could help to improve the recovery and quality of stem cell preparation of mammalian testis.
[Show abstract][Hide abstract] ABSTRACT: Sulfur mustard (SM) has been identified as an important chemical weapon. During the Iran-Iraq war of 1980-88, the extensive usage of SM against Iranian civilians and military forces was proven. This agent has been shown to cause severe damage mainly in the skin, eyes, lungs, and respiratory tract in Iranian veterans. The most common disease is bronchiolitis obliterans (BO)). SM increases the endogenous production of reactive oxygen species (ROS). Superoxide dismutases (SODs) are known as protective antioxidants against the harmful effects of ROS. Twenty exposed SM individuals (43.2±6.4 years), and 10 normal controls (41.3±2.5 years) were enrolled in this study. Evaluation of SODs was performed by semiquantitative RT-PCR and immunohistochemistry. Our results demonstrated that CuZnSOD and MnSOD mRNA were up-regulated 2.79±1.09 and 2.49±1.11 folds, respectively in SM-injured patients in comparison with control levels. In contrast, Immunohistochemistry results showed downregulation of CuZnSOD protein expression in SM injured patients. Our results revealed that SODs may play an important role in cellular protection against oxidative stress due to mustard gas toxicity in airway wall of SM exposed patients.
Iranian journal of allergy, asthma, and immunology 06/2013; 12(2):153-60. · 0.65 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: INTRODUCTION: Bone marrow transplantation is a critical approach for the treatment of many hematological disorders. Success of this approach is dependent on many factors the most important of which is the number of hematopoietic stem cells along with an efficient stroma. Co-transplantation of efficient mesenchymal stem cells can greatly improve the outcome of transplantations. Current researches assign a critical role for hypoxia inducible factor (HIF)-1alpha in protection of various cells and tissues probably through induction of cytokines. To make this feature applicable to human bone marrow-derived mesenchymal stem cells, we manipulated these cells to over express HIF-1alpha gene. MATERIALS AND METHODS: Full-length cDNA of human HIF-1alpha was inserted into human bone marrow mesenchymal stem cells by pcDNA.3.1 non-viral plasmid vector, and the effect of this over expression on production of some hematopoietic growth factors was explored. Moreover, using a co-culture system, the interactive impact of HIF-1alpha-overexpressed mesenchymal stem cells on hematopoietic stem cells was evaluated. RESULTS: Over expression of HIF-1alpha in mesenchymal stem cells in normoxia increased production of one of the most important hematopoietic growth factors, Stem cell factor (also known as Steel factor or c-kit ligand). HIF-1alpha overexpression had no effect on production of other hematopoietic growth factors. In co-culture of mesenchymal stem cells-HIF-1alpha with hematopoietic stem cells, enhancement of colony formation and reduced differentiation of hematopoietic stem cells were observed. CONCLUSION: Over expression of HIF-1alpha in human bone marrow-derived mesenchymal stem cells can augment the production of some hematopoietic growth factors, and we suggest this response of mesenchymal stem cells could help to improve the outcome of bone marrow transplantation.
[Show abstract][Hide abstract] ABSTRACT: Despite many advantages of mesenchymal stem cells (MSCs) that make them suitable for cell therapy purposes, their therapeutic application has been limited due to their susceptibility to several stresses (e.g., nutrient-poor environment, oxidative stress, and hypoxic and masses of cytotoxic factors) to which they are exposed during their preparation and following transplantation. Hence, reinforcing MSCs against these stresses is a challenge for both basic and clinician scientists. Recently, much attention has been directed toward equipping MSCs with cytoprotective factors to strengthen them against unfavorable microenvironments. Here, we engineered MSCs with lipocalin 2 (Lcn2), a cytoprotective factor that is naturally induced following exposure of cells to stresses imposed by the microenvironment. Lcn2 overexpression not only did not interfere with the multidifferentiation capacity of the MSCs but also granted many protective properties to them. Lcn2 potentiated MSCs to withstand oxidative, hypoxia, and serum deprivation (SD) conditions via antagonizing their induced cytotoxicity and apoptosis. Adhesion rate of MSCs to coated culture plates was also enhanced by Lcn2 overexpression. In addition, Lcn2 induced antioxidants and upregulated some growth factors in MSCs. Our findings suggested a new strategy for prevention of graft cell death in MSC-based cell therapy.
Cell Stress and Chaperones 04/2013; · 2.48 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND AND AIMS: The major limiting factor in therapeutic application of mesenchymal stem cells (MSCs) is their high vulnerability during the early days of transplantation. Hence, researchers have been encouraged to find various strategies to make the cells resistant to different stresses before and after transplantation. Overexpression of HIF-1α in MSCs to confer resistance against harmful conditions was the aim of this study. METHODS: Using an in vitro approach, we engineered MSCs to overexpress HIF-1α and then evaluated their viability following exposure to hypoxic and oxidative stresses. The inherent expression of HIF-1α was downregulated by siRNA. Viability and apoptosis of the MSCs were then evaluated in vitro following their exposure to hypoxic and oxidative stress conditions. RESULTS: Whereas overexpression of HIF-1α in MSCs was protective against cell death and apoptosis triggered by hypoxic and oxidative stress conditions, its downregulation increased apoptosis and death rate. CONCLUSIONS: Our study is the first to demonstrate how human MSCs can be manipulated to gain protection against stresses that potentially limit their clinical application.
Archives of medical research 03/2013; · 1.88 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Objective(s): Spermatogonial Stem Cells (SSCs) maintain spermatogenesis throughout the life of the male. Because of the small number of SSCs in adult, enriching and culturing them is a crucial step prior to differentiation or transplantation. Maintenance of SSCs and transplantation or induction of in vitro spermio-genesis may provide a therapeutic strategy to treat male infertility. This study investigated the enrichment and proliferation of SSCs co-cultured with STO cells in the presence or absence of growth factors. Materials and Methods: Spermatogonial populations were enriched from the testis of 4-6 week-old male mice by MACS according to the expression of a specific marker, Thy-1. Isolated SSCs were cultured in the presence or absence of growth factors (GDNF, GFRα1 and EGF) on STO or gelatin-coated dishes for a week. Subsequently, the authors evaluated the effects of growth factors and STO on SSCs colonization by alkaline phosphates (AP) activity and flow cytometery of α6 and β1 integrins. Results: SSCs co-cultured with STO cells and growth factors developed colonization and AP activity as well as expression of α6 and β1 integrins (P≤0/05). Conclusion: Our present SSC-STO co-culture provides conditions that may allow efficient maintenance and proliferation of SSCs for the treatment of male infertility.
Iranian Journal of Basic Medical Science 02/2013; 16(2):134-139. · 0.24 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Spermatogonial stem cells (SSCs) maintain spermatogenesis throughout life in the male. Maintenance of SSCs and induction of spermiogenesis in vitro may provide a therapeutic strategy to treat male infertility. This study investigated in vitro differentiation of mouse SSCs in presence or absence of Sertoli cells, hormones and vitamins. Spermatogonial populations were enriched from testes of 4-6 week old males by magnetic activated cell sorting and anti-Thy-1 antibody. Sertoli cells isolated from 6-8 week old testes were enriched using lectin-DSA-coated plates. Isolated SSCs were cultured in the presence of Leukemia inhibitory factor (LIF) for 7 days in gelatin-coated dishes, then dissociated and cultured for 7 days in media lacking LIF in the presence or absence of Sertoli cells, with or without FSH, testosterone and vitamins. After one week, the effects of Sertoli cells ± supplementary media on SSC differentiation was evaluated by microscopy and expression of meiotic and postmeiotic transcripts using RT-PCR. SSC colonies had limited development after LIF removal alone, exhibiting low expression of meiotic (Scp3, Th2b) but not postmeiotic transcript, and loss of Stra8 and Dazl expression. SSCs co-cultured with Sertoli cells, hormones and vitamins developed spermatid-like cells expressing postmeiotic markers (TP1, TP2, Prm1) at levels over 2-fold higher than Sertoli cells or hormone/vitamins alone. Our present SSC-Sertoli co-culture provides conditions that may allow efficient in vitro differentiation of SSCs for the treatment of male infertility.
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND AND AIMS:
The major limiting factor in therapeutic application of mesenchymal stem cells (MSCs) is their high vulnerability during the early days of transplantation. Hence, researchers have been encouraged to find various strategies to make the cells resistant to different stresses before and after transplantation. Overexpression of HIF-1α in MSCs to confer resistance against harmful conditions was the aim of this study.
Using an in vitro approach, we engineered MSCs to overexpress HIF-1α and then evaluated their viability following exposure to hypoxic and oxidative stresses. The inherent expression of HIF-1α was downregulated by siRNA. Viability and apoptosis of the MSCs were then evaluated in vitro following their exposure to hypoxic and oxidative stress conditions.
Whereas overexpression of HIF-1α in MSCs was protective against cell death and apoptosis triggered by hypoxic and oxidative stress conditions, its downregulation increased apoptosis and death rate.
Our study is the first to demonstrate how human MSCs can be manipulated to gain protection against stresses that potentially limit their clinical application.
Archives of Medical Research 01/2013; · 2.08 Impact Factor