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Cell Journal [Yakhteh]. 2019; 21 (1): 78-85
in English | IMEMR | ID: emr-203101


Objective: The role of epigenetic in regulating of the gene expression profile the embryo has been documented. MicroRNAs [miRNAs] are one of these epigenetic mechanisms. Twins are valuable models in determining the relative contributions of genetics and the environment. In this study, we compared differences in the expression levels of 44 miRNAs in hematopoietic stem cells [HSCs] of identical twins to that of fraternal twins as a controls

Materials and Methods: In this experimental study, CD133+ HSCs were isolated from cord blood of identical and fraternal twins via magnetic-activated cell sorting [MACS]. Variation in of gene expression levels of 44 miRNAs were evaluated using quantitative reverse transcription-polymerase chain reaction [qRT-PCR]

Results: Significant differences in expression were observed in both fraternal and identical twins to varying degrees, but variations alteration in expression of the miRNAs were higher in fraternal twins

Conclusion: Identical twins had a positive correlation in miRNA expression, while the correlation was not statistically significant in fraternal twins. Altogether, more differences in miRNA expression level in fraternal twins can be attributed to the both genetics and the intrauterine environment. The contribution of the intrauterine environment and genetics to miRNAs expression in HSCs was estimated 8 and 92%, respectively. By comparing of miRNA expression in identical and fraternal twins and identification of their target genes and biological pathways, it could be possible to estimate the effects of genetics and the environment on a number of biological pathways

Cell Journal [Yakhteh]. 2018; 20 (2): 195-203
in English | IMEMR | ID: emr-198730


Objective: In order to clarify the role of microRNAs [miRNA] in megakaryocyte differentiation, we ran a microRNA microarray experiment to measure the expression level of 961 human miRNA in megakaryocytes differentiated from human umbilical cord blood CD133+ cells

Materials and Methods: In this experimental study, human CD133+ hematopoietic stem cells were collected from three human umbilical cord blood [UCB] samples, and then differentiated to the megakaryocytic lineage and characterized by flow cytometry, CFU-assay and ploidy analysis. Subsequently, microarray analysis was undertaken followed by quantitative polymerase chain reaction [qPCR] to validate differentially expressed miRNA identified in the microarray analysis

Results: A total of 10 and 14 miRNAs were upregulated [e.g. miR-1246 and miR-148-a] and down-regulated [e.g. miR- 551b and miR-10a] respectively during megakaryocyte differentiation, all of which were confirmed by qPCR. Analysis of targets of these miRNA showed that the majority of targets are transcription factors involved in megakaryopoiesis

Conclusion: We conclude that miRNA play an important role in megakaryocyte differentiation and may be used as targets to change the rate of differentiation and further our understanding of the biology of megakaryocyte commitment

Cell Journal [Yakhteh]. 2018; 20 (1): 1-9
in English | IMEMR | ID: emr-191489


Objective: In this study, we describe an efficient approach for stable knockdown of adenosine kinase [ADK] using lentiviral system, in an astrocytoma cell line and in human Wharton's jelly mesenchymal stem cells [hWJMSCs]. These sources of stem cells besides having multilineage differentiation potential and immunomodulatory activities, are easily available in unlimited numbers, do not raise ethical concerns and are attractive for gene manipulation and cell-based gene therapy

Materials and Methods: In this experimental study, we targeted adenosine kinase mRNA at 3' and performed coding sequences using eight miR-based expressing cassettes of anti-ADK short hairpin RNA [shRNAs]. First, these cassettes with scrambled control sequences were cloned into expressing lentiviral pGIPZ vector. Quantitative real time-polymerase chain reaction [qRT-PCR] was used to screen multi-cassettes anti-ADK miR-shRNAs in stably transduced U-251 MG cell line and measuring ADK gene expression at mRNA level. Extracted WJMSCs were characterized using flow cytometry for expressing mesenchymal specific marker [CD44+] and lack of expression of hematopoietic lineage marker [CD45-]. Then, the lentiviral vector that expressed the most efficient anti-ADK miR-shRNA, was employed to stably transduce WJMSCs

Results: Transfection of anti-ADK miR-shRNAs in HEK293T cells using CaPO4 method showed high efficiency. We successfully transduced U-251 cell line by recombinant lentiviruses and screened eight cassettes of anti-ADK miR- shRNAs in stably transduced U-251 MG cell line by qRT-PCR. RNAi-mediated down-regulation of ADK by lentiviral system indicated up to 95% down-regulation of ADK. Following lentiviral transduction of WJMSCs with anti-ADK miR- shRNA expression cassette, we also implicated, down-regulation of ADK up to 95% by qRT-PCR and confirmed it by western blot analysis at the protein level

Conclusion: Our findings indicate efficient usage of shRNA cassette for ADK knockdown. Engineered WJMSCs with genome editing methods like CRISPR/cas9 or more safe viral systems such as adeno-associated vectors [AAV] might be an attractive source in cell-based gene therapy and may have therapeutic potential for epilepsy

Journal of Tehran University Heart Center [The]. 2017; 12 (2): 65-71
in English | IMEMR | ID: emr-190813


Background: myocardial infarction is the main cause of death worldwide. Angiogenesis, a promising new therapy for the treatment of diffuse coronary artery disease, shows a poor response to conventional revascularization techniques. This study focused on improving myocardial function using endothelial cells [ECs] and mesenchymal stem cells [MSCs] in a sheep animal model

Methods: acute myocardial infarction was induced in 18 sheep [12 treated cases and 6 controls]. Autologous MSCs and ECs were injected in the infarcted area and the border zone. Two months after transplantation, echocardiography, electron microscopy, and immunohistochemistry were performed

Results: echocardiography in both MSC and EC groups revealed a significant improvement in the ejection fraction compared with the control group [p value < 0.05]. Vascular density, estimated by antibodies against the von Willebrand factor and smooth muscle actin, increased in both study groups. The pattern of vascularity in the MSC and EC groups was diffused. The electron microscopic evaluation of the infracted areas revealed cardiomyocytes in variable stages of development in the border zone in both EC and MSC groups

Conclusion: both ECs and MSCs were able to promote angiogenesis and improve cardiac function. Presumably, MSCs differentiate into ECs and cause angiogenesis as it occurs for ECs

IBJ-Iranian Biomedical Journal. 2017; 21 (4): 218-227
in English | IMEMR | ID: emr-189231


Background: Islet transplantation could be an ideal alternative treatment to insulin therapy for type 1 diabetes Mellitus [T1DM]. This clinical and experimental field requires a model that covers problems such as requiring a large number of functional and viable islets, the optimal transplantation site, and the prevention of islet dispersion. Hence, the methods of choice for isolation of functional islets and transplantation are crucial

Methods: The present study has introduced an experimental model that overcomes some critical issues in islet transplantation, including in situ pancreas perfusion by digestive enzymes through common bile duct. In comparison with conventional methods, we inflated the pancreas in Petri dishes with only 1 ml collagenase type XI solution, which was followed by hand-picking isolation or Ficoll gradient separation to purify the islets. Then we used a hydrogel composite in which the islets were embedded and transplanted into the peritoneal cavity of the streptozotocin-induced diabetic C57BL/6 mice

Results: As compared to the yield of the classical methods, in our modified technique, the mean yield of isolation was about 130-200 viable islets/mouse pancreas. In vitro glucosemediated insulin secretion assay indicated an appropriate response in isolated islets. In addition, data from in vivo experiments revealed that the allograft remarkably maintained blood glucose levels under 400 mg/dl and hydrogel composite prevents the passage of immune cells

Conclusion: In the model presented here, the rapid islet isolation technique and the application of biomimetic hydrogel wrapping of islets could facilitate islet transplantation procedures

Animals, Laboratory , Biomimetic Materials , Biomimetics , Hydrogels , Diabetes Mellitus, Type 1 , Mice , Diabetes Mellitus, Experimental , Streptozocin
Novelty in Biomedicine. 2016; 4 (3): 100-104
in English | IMEMR | ID: emr-183714


Background: in this study, we compared the effect of ibuprofen [IB] while incorporating by Poly Lactic-co-Glycolic Acid [PLGA] nanofiber on expression of adhesion molecules ICAM-1 and VCAM-1 in a mice adhesion model

Materials and Methods: using an adhesion model were induced in mice, PLGA-IB and PLGA membranes and IB were sutured between the abdominal wall and peritoneum after surgical operation to reveal the best membrane for prevention of postoperative adhesion bands by comparison of ICAM-1 and VCAM-1 expression

Results: compared with other groups, PLGA-IB showed a greater ability to reduce ICAM-1 and VCAM-1 expression

Conclusion: these results suggested that in considering the FDA approved polymers, PLGA-IB could be introduced as a potential candidate for prevention of abdominal post-surgery inflammation and adhesion band formation after surgeries

Cell Journal [Yakhteh]. 2016; 18 (3): 322-331
in English | IMEMR | ID: emr-183766


Objective: receptor activator of nuclear factor-kappa B ligand [RANKL] appears to be an osteoclast-activating factor, bearing an important role in the pathogenesis of multiple myeloma. Some studies demonstrated that U-266 myeloma cell line and primary myeloma cells expressed RANK and RANKL. It had been reported that the expression of myeloid and monocytoid markers was increased by co-culturing myeloma cells with hematopoietic stem cells [HSCs]. This study also attempted to show the molecular mechanism of RANK and RANKL on differentiation capability of human cord blood HSC to osteoclast, as well as expression of calcitonin receptor [CTR] on cord blood HSC surface

Materials and Methods: in this experimental study, CD133[+] hematopoietic stem cells were isolated from umbilical cord blood and cultured in the presence of macrophage colony-stimulating factor [M-CSF] and RANKL. Osteoclast differentiation was characterized by using tartrate-resistant acid phosphatase [TRAP] staining, giemsa staining, immunophenotyping, and reverse transcription-polymerase chain reaction [RT-PCR] assay for specific genes

Results: hematopoietic stem cells expressed RANK before and after differentiation into osteoclast. Compared to control group, flow cytometric results showed an increased expression of RANK after differentiation. Expression of CTR mRNA showed TRAP reaction was positive in some differentiated cells, including osteoclast cells

Conclusion: presence of RANKL and M-CSF in bone marrow could induce HSCs differentiation into osteoclast

Cell Journal [Yakhteh]. 2016; 18 (3): 353-361
in English | IMEMR | ID: emr-183770


Objective: micro-RNAs [miRNAs] are a class of posttranscriptional regulators that play crucial roles in various biological processes. Emerging evidence suggests a direct link between miRNAs and development of several diseases including type 2 diabetes [T2D]. In this study, we aimed to investigate the effect of predicted miRNA and target genes on insulin resistance

Materials and Methods: this experimental study was conducted on the C2C12 cell line. Using bioinformatics tools miRNA-135 and two respective target genes-insulin receptor [Insr] and vesicle associated membrane protein 2 [Vamp2]- were selected as potential factors involved in insulin resistance process. Levels of glucose uptake miRNA expression and respective gene targets were determined after cell transfaction by miR-135

Results: it was determined that Insr gene expression was significantly down-regulated in miR-135 transfected C2C12 cell line [P

Conclusion: our data indicated no change on the Vamp2 expression level after miRNA transfection, while expression level of Insr was reduced and miR-135 expression was contrarily increased leading to poor stimulation of glucose uptake through insulin, and development of insulin resistance phenotype in C2C12 cell line

Modares Journal of Medical Sciences, Pathobiology. 2016; 19 (1): 79-91
in Persian | IMEMR | ID: emr-185202


Objective: In the present study we investigated the effect of a dynamic culture in a shake flask bioreactor [SFB] on the proliferation and differentiation to osteoblasts for human mesenchymal stem cells [hMSCs] cultured on multilayered electrospun PCL-nHA scaffolds

Methods: First, we prepared PCL-nHA scaffolds by electrospinning. After culturing the hMSCs on the scaffolds in a static state, the seeded scaffolds were divided into two groups [static and SFB culture] and incubated up to 21 days. We assessed biocompatibility and cell differentiation by the MTT, calcium, and alkaline phosphatase [ALP] assays on days 7, 14, and 21

Results: The MTT assay evaluated hMSCs proliferation rate on the scaffold layers. There was greater cell proliferation [optical density values] on the layers in the bioreactor [OD=2.18] compared to the static state condition [OD=1.68] on day 21. In order to study osteogenic differentiation, we determined the amount of calcium deposition and ALP activity. We observed a 1.6-fold greater level of calcium deposition for the dynamic culture compared to the static culture, which showed increased cell differentiation within the bioreactor on day 21. The ALP results showed that during 14 days, ALP activity within the bioreactor was 1.55-fold higher than the static culture

Conclusion: The SFB culture displayed a higher proliferation and differentiation of stem cells on PCL-nHA multilayered scaffolds compared to the static state condition

IJB-Iranian Journal of Biotechnology. 2016; 14 (2): 41-49
in English | IMEMR | ID: emr-193911


Background: Monolayer electrospun scaffolds have already been used in bone tissue engineering due to their high surface-tovolume ratio, interconnectivity, similarity to natural bone extracellular matrix [ECM], and simple production

Objectives: The aim of this study was to evaluate the dynamic culture effect on osteogenic differentiation and mineralizationi into a compact cellular multilayer nHA-PCL electrospun construct. The dynamic culture was compared with static culture

Materials and Methods: The calcium content, alkaline phosphatase [ALP] activity and cell viability were investigated on days 3 and 7

Results: When the dynamic culture compared to static culture, the mineralization and ALP activity were increased in dynamic culture. After 7 days, calcium contents were 41.24 and 20.44 micro g.[cm[3]][-1], and also normalized ALP activity were 0.32 and 0.19[-1] in dynamic and static culture, respectively. Despite decreasing the cell viability until day 7, the scanning electron microscopy [SEM] results showed that, due to higher mineralization, a larger area of the construct was covered with calcium deposition in dynamic culture

Conclusions: The dynamic flow could improve ALP activity and mineralization into the compact cellular multilayer construct cultured in the perfusion bioreactor after 7 days. Fluid flow of media helped to facilitate the nutrients transportation into the construct and created uniform cellular construct with high mineralization. This construct can be applied for bone tissue engineering

AJMB-Avicenna Journal of Medical Biotechnology. 2016; 8 (1): 2-8
in English | IMEMR | ID: emr-174769


Background: The Definitive Endoderm [DE] differentiation using the undefined media and non-human feeders can cause contaminations in the generated cells for therapeutic applications. Therefore, generating safer and more appropriate DE cells is needed. This study compared five different methods to establish an appropriate method for inducing an efficient DE differentiation from Human Induced Pluripotent Stem Cells [hiPSCs] on an appropriate feeder in a more defined medium

Methods: Human Induced Pluripotent Stem Cells [hiPSCs] were cultured on inactivated feeders. Passaged hiPSCs, without feeder, were incubated for three days with Activin-A and different endodermal differentiation media including 1-FBS, 2-B27, 3- ITS and albumin fraction-V, 4-B27 and ITS and 5-like the third medium. The feeder cells in the first four methods were Mouse Embryonic Fibroblasts [MEFs] and in the fifth method were human adult bone marrow Mesenchymal Stem Cells [hMSCs]. DE markers FOXA2, SOX17 and CXCR4 and also pluripotency marker OCT4 were evaluated using qRT-PCR, as well as FOXA2 by the immunocytochemistry

Results: QRT-PCR analysis showed that after three days, the expression levels of DE and pluripotency markers in the differentiated hiPSCs among all five groups did not have any significant differences. Similarly, the immunocytochemistry analysis demonstrated that the differentiated hiPSCs expressed FOXA2, with no significant differences

Conclusion: Despite this similarity in the results, the third differentiation medium has more defined and cost effective components. Furthermore, hMSC, a human feeder, is safer than MEF. Therefore, the fifth method is preferable among other DE differentiation methods and can serve as a fundamental method helping the development of regenerative medicine

Cell Journal [Yakhteh]. 2016; 17 (4): 583-592
in English | IMEMR | ID: emr-179286


Today the regulatory role of microRNAs [miRs] is well characterized in many diverse cellular processes. MiR-based regulation is categorized under epigenetic regulatory mechanisms. These small non-coding RNAs participate in producing and maturing erythrocytes, expressing hematopoietic factors and regulating expression of globin genes by post-transcriptional gene silencing. The changes in expression of miRs [miR-144/-320/-451/-503] in thalassemic/sickle cells compared with normal erythrocytes may cause clinical severity. According to the suppressive effects of certain miRs [miR-15a/-16-1/-23a/-26b/-27a/-451] on a number of transcription factors [myeloblastosis oncogene [MYB], B-cell lymphoma 11A [BCL11A], GATA1, Krüppel-like factor 3 [KLF3] and specificity protein 1 [Sp1]] during beta globin gene expression, It has been possible to increasing ? globin gene expression and fetal hemoglobin [HbF] production. Therefore, this strategy can be used as a novel therapy in infusing HbF and improving clinical complications of patients with hemoglobinopathies

Cell Journal [Yakhteh]. 2016; 17 (4): 617-628
in English | IMEMR | ID: emr-179290


Objective: Gastric cancer [GC] is widely associated with chronic inflammation. The pro inflammatory microenvironment provides conditions that disrupt stem/progenitor cell proliferation and differentiation. The signal transducer and activator of transcrip-tion-3 [STAT3] signaling pathway is involved in inflammation and also contributes to the maintenance of embryonic stem cell [ESCs] pluripotency. Here, we have investi-gated the activation status of STAT3 in GC stem-like cells [GCSLCs]

Materials and Methods: In this experimental research, CSLCs derived from the human GC cell line MKN-45 and patient specimens, through spheroid body formation, characterized and then assayed for the STAT3 transcription factor expression in mRNA and protein level further to its activation

Results: Spheroid cells showed higher potential for spheroid formation than the parental cells. Furthemore, stemness genes NANOG, c-MYC and SOX-2 were over expressed in spheroids of MKN-45 and in patient samples. In MKN-45 spheroid cells, epithelial mesenchymal transition [EMT] related markers CDH2, SNAIL2, TWIST and VIMENTIN were upregulated [P<0.05], but we observed no change in expression of the E-cadherin epithelial marker. These cells exhibited more resistance to docetaxel [DTX] when compared with parental cells [P<0.05] according to the MTS assay. Although immunostaining and Western blotting showed expression of the STAT3 protein in both spheroids and parents, the mRNA level of STAT3 in spheroids was higher than the parents. Nuclear translocation of STAT3 was accompanied by more intensive phospho-STAT3 [p-STAT3] in spheroid structures relative to the parent cells according to flow cytometry analysis [P<0.05]

Conclusion: The present findings point to STAT3 over activation in GCSLCs. Complementary experiments are required to extend the role of STAT3 in stemness features and invasion properties of GCSCs and to consider the STAT3 pathway for CSC targeted therapy

Cell Journal [Yakhteh]. 2016; 18 (2): 165-178
in English | IMEMR | ID: emr-183006


Objective: MicroRNAs [miRNAs] are small endogenous non-coding regulatory RNAs that control mRNAs post-transcriptionally. Several mouse stem cells miRNAs are cloned differentially regulated in different hematopoietic lineages, suggesting their possible role in hematopoietic lineage differentiation. Recent studies have shown that specific miRNAs such as Mir-451 have key roles in erythropoiesis

Materials and Methods: In this experimental study, murine embryonic stem cells [mESCs] were infected with lentiviruses containing pCDH-Mir-451. Erythroid differentiation was assessed based on the expression level of transcriptional factors [Gata-1, Klf-1, Epor] and hemoglobin chains [alpha, beta, gamma, epsilon and zeta] genes using quantitative reverse transcriptase-polymerase chain reaction [qRT-PCR] and presence of erythroid surface antigens [TER-119 and CD235a] using flow cytometery. Colony-forming unit [CFU] assay was also on days 14thand 21thafter transduction

Results: Mature Mir-451 expression level increased by 3.434-fold relative to the untreated mESCs on day 4 after transduction [P<0.001]. Mir-451 up-regulation correlated with the induction of transcriptional factor [Gata-1, Klf-1, Epor] and hemoglobin chain [alpha, beta, gamma, epsilon and zeta] genes in mESCs [P<0.001] and also showed a strong correlation with presence of CD235a and Ter- 119 markers in these cells [13.084and 13.327-fold increse, respectively] [P<0.05]. Moreover, mESCs treated with pCDH-Mir-451 showed a significant raise in CFU-erythroid [CFU-E] colonies [5.2-fold] compared with untreated control group [P<0.05]

Conclusion: Our results showed that Mir-451 up-regulation strongly induces erythroid differentiation and maturation of mESCs. Overexpression of Mir-451 may have the potential to produce artificial red blood cells [RBCs] without the presence of any stimulatory cytokines

Cell Journal [Yakhteh]. 2016; 18 (2): 189-196
in English | IMEMR | ID: emr-183008


Objective: Treatment and repair of neurodegenerative diseases such as brain tumors, spinal cord injuries, and functional disorders, including Alzheimer's disease, are challenging problems. A common treatment approach for such disorders involves the use of mesenchymal stem cells [MSCs] as an alternative cell source to replace injured cells. However, use of these cells in hosts may potentially cause adverse outcomes such as tumorigenesis and uncontrolled differentiation. In attempt to generate mesenchymal derived neural cells, we have infected MSCs with recombinant lentiviruses that expressed nerve growth factor [NGF] and assessed their neural lineage genes

Materials and Methods: In this experimental study, we cloned the NGF gene sequence into a helper dependent lentiviral vector that contained the green fluorescent protein [GFP] gene. The recombinant vector was amplified in DH5 bacterial cells. Recombinant viruses were generated in the human embryonic kidney 293 [HEK-293] packaging cell line with the helper vectors and analyzed under fluorescent microscopy. Bone marrow mesenchymal cells were infected by recombinant viruses for three days followed by assessment of neural differentiation. We evaluated expression of NGF through measurement of the NGF protein in culture medium by ELISA; neural specific genes were quantified by real-time polymerase chain reaction [PCR]

Results: We observed neural morphological changes after three days. Quantitative PCR showed that expressions of NESTIN, glial derived neurotrophic factor [GDNF], glial fibrillary acidic protein [GFAP] and Microtubule-associated protein 2 [MAP2] genes increased following induction of NGF overexpression, whereas expressions of endogenous NGF and brain derived neural growth factor [BDNF] genes reduced

Conclusion: Ectopic expression of NGF can induce neurogenesis in MSCs. Direct injection of MSCs may cause tumorigenesis and an undesirable outcome. Therefore an alternative choice to overcome this obstacle may be the utilization of differentiated neural stem cells

Cell Journal [Yakhteh]. 2015; 17 (3): 461-470
in English | IMEMR | ID: emr-174879


Objective: MicroRNAs [miRNAs] are a class of small non-coding RNAs that play pivotal roles in many biological processes such as regulating skeletal muscle development where alterations in miRNA expression are reported during myogenesis. In this study, we aimed to investigate the impact of predicted miRNAs and their target genes on the myoblast to myocyte differentiation process

Materials and Methods: This experimental study was conducted on the C2C12 cell line. Using a bioinformatics approach, miR-214 and miR-135 were selected according to their targets as potential factors in myoblast to myocyte differentiation induced by 3% horse serum. Immunocytochemistry [ICC] was undertaken to confirm the differentiation process and quantitative real-time polymerase chain reaction [PCR] to determine the expression level of miRNAs and their targets

Results: During myoblast to myocyte differentiation, miR-214 was significantly down-regulated while miRNA-135, Irs2, Akt2 and Insr were overexpressed during the process

Conclusion: miR-214 and miR-135 are potential regulators of myogenesis and are involved in skeletal muscle development through regulating the IRS/PI3K pathway

AJMB-Avicenna Journal of Medical Biotechnology. 2015; 7 (1): 32-38
in English | IMEMR | ID: emr-159978


Development of tissue engineering and regenerative medicine has led to designing scaffolds and their modification to provide a better microenvironment which mimics the natural niche of the cells. Gelatin surface modification was applied to improve scaffold flexibility and cytocompatibility. PLLA/PCL aligned fibrous scaffold was fabricated using electrospinning method. ADSCs were seeded after O[2] plasma treatment and gelatin coating of the scaffolds. The morphological and mechanical properties of blends were assessed by Scanning Electron Microscopy [SEM], tensile test and ATR-FTIR. The cells proliferation was evaluated by MTT assay. Based on the results, it is supposed that gelatin coating is a brilliant method of surface modification which significantly increases the mechanical properties of scaffold without any changes on the construction or on the direction of nanofibers which conducts cell's elongation. MTT analysis exhibited that ADSCs attachment, viability and proliferation significantly [p<0.05] increased after gelatin treatment. Gelatin surface modification is a highly beneficial method to improve cytocompatibility, flexibility and mechanical features of the scaffolds which doesn't affect the nanofibers construction. Proliferation of Adipose Derived Stem Cells [ADSCs] as a remarkable source of stem cells was investigated for the first time on PLLA/PCL hybrid scaffold

Gelatin , Stem Cells , Adipose Tissue , Nanofibers , Tissue Engineering
Cell Journal [Yakhteh]. 2015; 17 (2): 231-242
in English | IMEMR | ID: emr-166904


Type I diabetes is an immunologically-mediated devastation of insulin producing cells [IPCs] in the pancreatic islet. Stem cells that produce beta-cells are a new promising tool. Adult stem cells such as mesenchymal stem cells [MSCs] are self renewing multi potent cells showing capabilities to differentiate into ectodermal, mesodermal and endodermal tissues. Pancreatic and duodenal homeobox factor 1 [PDX1] is a master regulator gene required for embryonic development of the pancreas and is crucial for normal pancreatic islets activities in adults. We induced the over-expression of the PDX1 gene in human bone marrow MSCs [BM-MSCs] by Lenti-PDX1 in order to generate IPCs. Next, we examine the ability of the cells by measuring insulin/c-peptide production and INSULIN and PDX1 gene expressions. After transduction, MSCs changed their morphology at day 5 and gradually differentiated into IPCs. INSULIN and PDX1 expressions were confirmed by real time polymerase chain reaction [RT-PCR] and immunostaining. IPC secreted insulin and C-peptide in the media that contained different glucose concentrations. MSCs differentiated into IPCs by genetic manipulation. Our result showed that lentiviral vectors could deliver PDX1 gene to MSCs and induce pancreatic differentiation

Cell Journal [Yakhteh]. 2015; 16 (4): 466-475
in English | IMEMR | ID: emr-154849


Many studies have focused on the epigenetic characteristics of donor cells to improve somatic cell nuclear transfer [SCNT]. We hypothesized that the epigenetic status and chromatin structure of undifferentiated bovine adipose tissue-derived stem cells [BADSCs] would not remain constant during different passages. The objective of this study was to determine the mRNA expression patterns of DNA methyltransferases [DNMT1, DNMT3a, DNMT3b] and histone deacetyltransferses [HDAC1, HDAC2, HDAC3] in BADSCs. In addition, we compared the measured levels of octamer binding protein-4 expression [OCT4] and acetylation of H3K9 [H3K9ac] in BADSCs cultures and different passages in vitro. In this experimental study, subcutaneous fat was obtained from adult cows immediately post-mortem. Relative level of DNMTs and HDACs was examined using quantitative real time polymerase chain reaction [q-PCR], and the level of OCT4 and H3K9ac was analyzed by flow cytometry at passages 3 [P3], 5 [P5] and 7 [P7]. The OCT4 protein level was similar at P3 and P5 but a significant decrease in its level was seen at P7. The highest and lowest levels of H3K9ac were observed at P5 and P7, respectively. At P5, the expression of HDACs and DNMTs was significantly decreased. In contrast, a remarkable increase in the expression of DNMTs was observed at P7. Our data demonstrated that the epigenetic status of BADSCs was variable during culture. The P5 cells showed the highest level of stemness and multipotency and the lowest level of chromatin compaction. Therefore, we suggest that P5 cells may be more efficient for SCNT compared with other passages

Animals , DNA Methylation , Histones , RNA, Messenger , Adipose Tissue , Histone Deacetylase 1 , Histone Deacetylase 2 , Histone Deacetylases , Cattle
IJI-Iranian Journal of Immunology. 2015; 12 (4): 226-239
in English | IMEMR | ID: emr-181360


Background: Differentiation, migratory properties and availability of MesenchymalStromal Cells [MSC] have become an important part of biomedical research. However,the functional heterogeneity of cells derived from different tissues has hamperedproviding definitive phenotypic markers for these cells

Objective: To characterize andcompare the phenotype and cytokines of adipose derived MSCs [AD-MSCs] andtumoral-MSCs [T-MSCs] isolated from mammary tumors of BALB/c mice

Methods:Immunophenotyping and in vitro differentiation tests were used for MSCcharacterization. Cytokine and enzyme profiles were assessed using ELISA and RealtimePCR, respectively

Results: T-MSCs expressed significantly higher levels of HLADR[p=0.04]. Higher levels of PGE2 and COX-2 enzyme were also observed in TMSCs[p=0.07 and p=0.00, respectively]. Additionally, T-MSCs expressed higher levelsof iNOS and MMP9 [p=0.01 and p=0.01, respectively]. T-MSCs were also able toinduce higher levels of proliferation and migration of HUVEC endothelial cells inwound scratch assay compared to AD-MSCs [p=0.015]

Conclusion: Functionaldifferences showed by the surface markers of MSCs, cytokine and enzyme productionindicate the effect of different microenvironments on MSCs phenotype and function