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1.
Neurosci Lett ; 769: 136392, 2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-34902517

RESUMO

Stem cells from human exfoliated deciduous teeth (SHED) have stromal-derived inducing activity (SDIA): which means these stromal cells induce neural differentiation where they are used as a substratum for embryonic stem cell (ESCs) culture. Recent studies show that mitochondria or mitochondrial products, as paracrine factors, can be released and transferred from one cell to another. With this information, we were curious to know whether in the SDIA co-culture system, SHED release or donate their mitochondria to ESCs. For this purpose, before co-culture, SHED s' mitochondria and ESCs s' cell membranes were separately labeled with specific fluorescent probes. After co-culture, SHED s' mitochondria were tracked by fluorescent microscope and flow cytometry analysis. Co-culture also performed in the presence of inhibitors that block probable transfer pathways suchlike tunneling nanotubes, gap junctions or vesicles. Results showed that mitochondrial transfer takes place from SHED to ESCs. This transfer partly occurs by tunneling nanotubes and not through gap junctions or vesicles; also was not dependent on intracellular calcium level. This kind of horizontal gene transfer may open a new prospect for further research on probable role of mitochondria on fate choice and neural induction processes.


Assuntos
Comunicação Celular , Estruturas da Membrana Celular/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Mitocôndrias/fisiologia , Cálcio/metabolismo , Linhagem Celular , Técnicas de Cocultura/métodos , Matriz Extracelular/metabolismo , Junções Comunicantes/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/fisiologia , Mitocôndrias/metabolismo , Nanotubos , Dente Decíduo/citologia
3.
Sci Rep ; 10(1): 5076, 2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-32193457

RESUMO

Aberrant patterns of DNA methylation are consistent events in SCNT derived embryos and mechanistically are believed to be related to abnormal development. While some epigenetic drugs have been used in attempts to improve SCNT efficiency but some concerns remained toward the safety of these drugs on the health of future offspring. Folate is an essential cofactor in one-carbon cycle for conversion of homocysteine to methionine, thereby ensuring supply of SAM, the universal methyl donor for many biological methylation reactions including DNA methylation. Therefore, in vitro DNA hypo-methylation can be induced by folate deprivation and this study aims at deciphering the role of folic acid deprivation in culture medium of BFFs for 6 days on SCNT efficiency. Our data revealed that culture of fibroblast cells in folate- medium containing 0.5% FBS did not alter the cell cycle compared to other groups. Flowcytometric analysis revealed that DNA methylation (5-mC level) in folate deprived cells cultured in 0.5% serum was decreased compared to folate+ group. The result of bisulfite sequencing was in accordance with flowcytometric analysis, which indicated a decrease in DNA methylation of POU5F1 promoter. Gene expression analysis revealed an increase in expression of POU5F1 gene in folate- group. The nuclear area of the cells in folate- group was significantly larger than folate+ group. Induced DNA hypomethylation by folate deprivation in the folate- group significantly improved blastocyst rate compared to the folate+ group. DNA methylation level in POU5F1 promoter and ICR of H19 and IGF2 of SCNT derived embryos in the folate- group was similar to the IVF derived blastocysts. In conclusion, our results proposes a promising "non-chemical" instead of "chemical" approach using inhibitors of epigenetic modifier enzymes for improving mammalian SCNT efficiency for agricultural and biomedical purposes.


Assuntos
Metilação de DNA , Embrião de Mamíferos , Fibroblastos , Ácido Fólico/fisiologia , Técnicas de Transferência Nuclear , Animais , Bovinos , Células Cultivadas , Feminino , Ácido Fólico/farmacologia , Expressão Gênica , Homocisteína/metabolismo , Metionina , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Regiões Promotoras Genéticas
4.
Iran Biomed J ; 21(1): 16-23, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27432596

RESUMO

BACKGROUND: Imprinted genes are a unique subset of few genes that have been differentially methylated region (DMR) in a parental origin-dependent manner during gametogenesis, and these genes are highly protected during pre-implantation epigenetic reprogramming. Several studies have shown that the particular vulnerability of imprinting genes during suboptimal pre- and peri-conception micro-environments often is occurred by assisted reproduction techniques (ART). This study investigated the methylation status of H19/IGF2 DMR at high-quality expanding/expanded human blastocysts donated by healthy individuals to evaluate the risks linked to ART. METHODS: Methylation levels of H19/IGF2 DMR were analyzed by bisulfite conversion and sequencing at 18 CpG sites (CpGs) located in this region. RESULTS: The overall percentage of methylated CpGs and the proportion of hyper-methylated clones of H19/IGF2 DMR in analyzed blastocysts were 37.85±4.87% and 43.75±5.1%, respectively. For validation of our technique, the corresponding methylation levels of peripheral human lymphocytes were defined (49.52±1.86% and 50%, respectively). CONCLUSIONS: Considering the absence of in vivo- produced human embryos, it is not possible to conclude that the methylation found in H19/IGF2 DMR is actually normal or abnormal. Regarding the possible risks associated with ART, the procedures should be optimized in order to at least reduce some of the epigenetic risks.


Assuntos
Blastocisto/citologia , Metilação de DNA/genética , Epigênese Genética/genética , Impressão Genômica/genética , Fator de Crescimento Insulin-Like II/genética , RNA Longo não Codificante/genética , Ilhas de CpG/genética , Humanos , Linfócitos/citologia , Técnicas de Reprodução Assistida
5.
Cryobiology ; 73(2): 168-74, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27497663

RESUMO

One of the most widely used assisted reproductive technology (ART) is vitrification. The aim of this study is to evaluate DNA methylation of H19/IGF2 differentially methylation region (DMR) in in vitro produced human blastocysts derived from non-vitrified and vitrified day3 embryos. Day3 embryos derived from ICSI cycles from fertile couples referring for family balancing program were either biopsied or vitrified/warmed and subsequently biopsied. Following biopsy, embryos were cultured to day 5. Day5 blastocysts with desired sex were transferred or vitrified for future use. Blastocysts with un-desired sex were donated for research. The assessment of the embryos was performed in two non-vitrified and vitrified groups. Methylation level of H19/IGF2 DMR was analysed by bisulfite conversion and sequencing at 18 CpG sites (CpGs) located in this region. Results showed that the overall methylated CpGs percentages of this region in the vitrified and non-vitrified groups were 35.3% ± 3.6 and 38.27 ± 4.1%, respectively. The difference between the two groups was not significant. Vitrification of day3 embryo appears to have no adverse effect on DNA methylation status of H19/IGF2 DMR of embryos cultured in vitro to blastocyst stage. These data may have implications for performing frozen embryo cycles transfer instead of fresh embryo transfer cycles, owing to the naturally synchronized uterus and subsequently improved endometrial receptivity in frozen embryo transfer instead of imbalanced hormonal milieu in fresh embryo transfer cycles.


Assuntos
Blastocisto/metabolismo , Criopreservação/métodos , Metilação de DNA/genética , Impressão Genômica/genética , Vitrificação , Animais , Blastocisto/citologia , Transferência Embrionária , Feminino , Humanos , Técnicas de Reprodução Assistida
6.
Mol Cell Biochem ; 420(1-2): 29-42, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27435855

RESUMO

Parkinson's disease (PD) can degenerate dopaminergic (DA) neurons in midbrain, substantia-nigra pars compacta. Alleviation of its symptoms and protection of normal neurons against degeneration are the main aspects of researches to establish novel therapeutic strategies. PPARγ as a member of PPARs have shown neuroprotection in a number of neurodegenerative disorders such as Alzheimer's disease and PD. Nuclear receptor related 1 protein (Nurr1) is, respectively, member of NR4A family and has received great attentions as potential target for development, maintenance, and survival of DA neurons. Based on neuroprotective effects of PPARγ and dual role of Nurr1 in anti-inflammatory pathways and development of DA neurons, we hypothesize that PPARγ and Nurr1 agonists alone and in combined form can be targets for neuroprotective therapeutic development for PD in vitro model. 1-Methyl-4-phenylpyridinium (MPP(+)) induced neurotoxicity in PC12 cells as an in vitro model for PD studies. Treatment/cotreatment with PPARγ and Nurr1 agonists 24 h prior to MPP(+) induction enhanced the viability of PC12 cell. The viability of PC12 cells was determined by MTS test. Mitochondrial membrane potential (MMP) and intracellular reactive oxygen species (ROS) were detected by flow cytometry. In addition, the relative expression of four genes including TH (the marker of DA neurons), Ephrin A1, Nurr1, and Ferritin light chain were assessed by RT-qPCR. In the MPP(+)-pretreated PC12 cells, PPARγ and Nurr1 agonists and their combined form resulted in a decrease in the cell death rate. Moreover, production of intracellular ROS and MMP modulated by MPP(+) was decreased by PPARγ and Nurr1 agonists' treatment alone and in the combined form.


Assuntos
1-Metil-4-fenilpiridínio/toxicidade , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares , PPAR gama , Espécies Reativas de Oxigênio/metabolismo , Animais , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/agonistas , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Células PC12 , PPAR gama/agonistas , PPAR gama/metabolismo , Ratos
7.
Iran J Biotechnol ; 14(3): 169-176, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28959333

RESUMO

BACKGROUND: Promyelocytic leukemia protein (PML) is a tumor suppressor protein that is involved in myeloid cell differentiation in response to retinoic acid (RA). In addition, RA acts as a natural morphogen in neural development. OBJECTIVES: This study aimed to examine PML gene expression in different stages of in vitro neural differentiation of NT2 cells, and to investigate the possible role of PML in pluripotency and/or neural development. MATERIALS AND METHODS: RA was used as a neural inducer for in vitro neural differentiation of NT2 cells. During this process PML mRNA and protein levels were assessed by quantitative real time RT-PCR (QRT-PCR) and Immunoblotting, respectively. Furthermore bisulfite sequencing PCR (BSP) was used to assess PML promoter methylation in NT2 cells and NT2 derived neuronal precursor cells (NT2.NPCs). RESULTS: QRT-PCR results showed that, PML had maximum expression with significant differences in NT2 derived neuronal precursor cells relative to NT2 cells and NT2 derived neural cells (NT2.NCs). Numerous isoforms of PML with different intensities appeared in immunoblots of pluripotent NT2 cells, NT2.NPCs, and NT2.NCs. Furthermore, the methylation of the PML promoter in NT2.NCs was 2.6 percent lower than NT2 cell. CONCLUSIONS: The observed differences in PML expression in different cellular stages possibly could be attributed to the fact that PML in each developmental state might be involved in different cell signaling machinery and different functions. The appearance of different PML isoforms with more intensity in neural progenitor cells; may suggest apossible role for this protein in neural development.

8.
Cell J ; 17(1): 37-48, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25870833

RESUMO

OBJECTIVE: The neural crest is a transient structure of early vertebrate embryos that generates neural crest cells (NCCs). These cells can migrate throughout the body and produce a diverse array of mature tissue types. Due to the ethical and technical problems surrounding the isolation of these early human embryo cells, researchers have focused on in vitro studies to produce NCCs and increase their knowledge of neural crest development. MATERIALS AND METHODS: In this experimental study, we cultured human embryonic stem cells (hESCs) on stromal stem cells from human exfoliated deciduous teeth (SHED) for a two-week period. We used different approaches to characterize these differentiated cells as neural precursor cells (NPCs) and NCCs. RESULTS: In the first co-culture week, hESCs appeared as crater-like structures with marginal rosettes. NPCs derived from these structures expressed the early neural crest marker p75 in addition to numerous other genes associated with neural crest induction such as SNAIL, SLUG, PTX3 and SOX9. Flow cytometry analysis showed 70% of the cells were AP2/P75 positive. Moreover, the cells were able to self-renew, sustain multipotent differentiation potential, and readily form neurospheres in suspension culture. CONCLUSION: SHED, as an adult stem cell with a neural crest origin, has stromal-derived inducing activity (SDIA) and can be used as an NCC inducer from hESCs. These cells provide an invaluable resource to study neural crest differentiation in both normal and disordered human neural crest development.

9.
Int Wound J ; 12(1): 27-31, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23551454

RESUMO

Fibrocytes are unique bone marrow-derived cells with great potential in wound healing. Hence, the aim of this study was to determine the safety and efficacy of the applied circulating fibrocytes in the treatment of non healing diabetic foot ulcers. Peripheral blood mononuclear cells were isolated by centrifugation through Ficoll-Paque method. After 3 days, the non adherent cells were removed by a single, gentle aspiration. Adherent cells were cultured in the same medium for 10 days. The cells were characterised using mouse anti-human-CD45-fluorescein isothiocyanate (FITC) and mouse anti-human-collagen I, and also characterised by immunofluorescence microscopy using the above mentioned antibodies. Sterility measures were applied for clinical evaluation. Based on the literature review, cell transplantation generally requires at least 3 × 10(6) cells regarding efficacy measures. As fibrocytes are non proliferating cells, 350 ml patient's blood is required to prepare patient-specific serum before cell isolation and culture, and 85 ml patient's blood is needed for cell isolation and differentiation on cell transplantation applications. In our survey, no diabetic patient was inclined to be donor of such blood volume, mainly because of their pre-assumption that they are anaemic. It is concluded that fibrocytes do not seem to be candidate cells for cell therapy in the treatment of diabetic foot ulcers because of the rarity of this cell population in circulation.


Assuntos
Separação Celular/métodos , Transplante de Células/métodos , Pé Diabético/terapia , Leucócitos Mononucleares/transplante , Aceitação pelo Paciente de Cuidados de Saúde , Humanos
10.
Avicenna J Med Biotechnol ; 6(2): 119-22, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24834314

RESUMO

BACKGROUND: In vitro simulation of developmental processes is an invaluable tool to shed light on the intrinsic mechanism of developmental biosystems such as central nervous system in mammals. Chick somites have been used to simulate the neural differentiation of human neural progenitor cells. In the present study, we aimed to indicate whether somites have the ability to express required neural differentiation factors at mRNA level. METHODS: Chick embryos were isolated from the yolk surface of the fertilized eggs and somites were subsequently isolated from embryos under a dissecting microscope. Total RNA of the somites was extracted and RT-PCR carried out with specific primers of cerberus, chordin, FGF8, follistatin and noggin. RESULTS: Data showed that five aforementioned factors were co-expressed after 7 days in vitro by somites. CONCLUSION: We concluded that neural induction property of somites appeared by production of required neural differentiation factors including cerberus, chordin, FGF8, follistatin and noggin.

11.
J Biomed Mater Res A ; 102(12): 4554-67, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24677613

RESUMO

Artificial nanofiber nerve guides have gained huge interest in bridging nerve gaps and associated peripheral nerve regeneration due to its high surface area, flexibility and porous structure. In this study, electrospun poly (ε-caprolactone)/gelatin (PCL/Gel) nanofibrous mats were fabricated, rolled around a copper wire and fixed by medical grade adhesive to obtain a tubular shaped bio-graft, to bridge 10 mm sciatic nerve gap in in vivo rat models. Stem cells from human exfoliated deciduous tooth (SHED) were transplanted to the site of nerve injury through the nanofibrous nerve guides. In vivo experiments were performed in animal models after creating a sciatic nerve gap, such that the nerve gap was grafted using (i) nanofiber nerve guide (ii) nanofiber nerve guide seeded with SHED (iii) suturing, while an untreated nerve gap remained as the negative control. In vitro cell culture study was carried out for primary investigation of SHED-nanofiber interaction and its viability within the nerve guides after 2 and 16 weeks of implantation time. Walking track analysis, plantar test, electrophysiology and immunohistochemistry were performed to evaluate functional recovery during nerve regeneration. Vascularization was also investigated by hematoxilin/eosine (H&E) staining. Overall results showed that the SHED seeded on nanofibrous nerve guide could survive and promote axonal regeneration in rat sciatic nerves, whereby the biocompatible PCL/Gel nerve guide with cells can support axonal regeneration and could be a promising tissue engineered graft for peripheral nerve regeneration.


Assuntos
Polpa Dentária/metabolismo , Gelatina , Regeneração Tecidual Guiada , Nanofibras/química , Regeneração Nervosa/efeitos dos fármacos , Nervos Periféricos/fisiologia , Poliésteres , Células-Tronco/metabolismo , Animais , Células Cultivadas , Polpa Dentária/citologia , Gelatina/química , Gelatina/farmacologia , Humanos , Masculino , Poliésteres/química , Poliésteres/farmacologia , Ratos , Ratos Wistar , Células-Tronco/citologia
12.
J Biomed Mater Res B Appl Biomater ; 102(3): 447-54, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24039141

RESUMO

The potential of pluripotent embryonic stem cells (ESCs) isolated from the inner mass of blastocysts are investigated for its ability to differentiate on biocompatible electrospun nanofibers, for regeneration of the myocardially infracted heart. Nanostructured poly(d,l-lactide-co-glycolide)/collagen (PLGA/Col) scaffolds with fiber diameters in the range of 300 ± 65 nm, was fabricated by electrospinning to mimic the extracellular matrix of the native tissue. During the culture of embryoid bodies outgrowth on the scaffolds, and further differentiation of ESCs to cardiomyocytes, the PLGA/Col nanofibers was found better than that of the electrospun PLGA nanofibers, where a better interaction and growth of ESC differentiated cardiomyocytes was observed on the composite scaffolds. The phenotypical characteristics of ESC-derived cardiomyocytes and molecular protein expression were carried out by scanning electron microscopy and immunocytochemistry, respectively. Our studies highlight the significance of a suitable material, its architecture, and cell-biomaterial interactions that is essential at a nanoscale level signifying the application of a bioengineered cardiac graft for stem cell differentiation and transplantation, which could be an intriguing strategy for cardiac regeneration.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Nanofibras , Animais , Colágeno , Células-Tronco Embrionárias/ultraestrutura , Imuno-Histoquímica , Células-Tronco Pluripotentes Induzidas/ultraestrutura , Ácido Láctico , Fenômenos Mecânicos , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Varredura , Miócitos Cardíacos/ultraestrutura , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Resistência à Tração , Engenharia Tecidual , Alicerces Teciduais , Água/química
13.
Eur J Cell Biol ; 92(4-5): 160-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23628590

RESUMO

The aim of this study was to evaluate the influence of peroxisome proliferator-activated receptor γ (PPARγ) on self-renewal of mouse embryonic stem cells (mESCs) in the presence and absence of leukemia inhibitory factor (LIF). We demonstrated that in the presence of LIF, the activation of PPARγ by Rosiglitazone led to an increased proliferation of mESCs whereas PPARγ antagonist (GW9662) reversed this effect. Additionally, upon PPARγ activation, LIF increased PPARγ expression and resulted in the degradation of suppressor of cytokine signaling 3 (SOCS3), an important negative regulator of LIF/signal transducers and activators of transcription 3 (STAT3)-pathway. In the absence of LIF, Rosiglitazone decreased proliferation of mESCs. In this state, our results showed that extracellular signal-regulated kinase (ERK) proteins were activated and resulted in the suppression of Nanog expression, an important pluripotency determinant, whereas it did not affect Oct4 expression. These results suggest that the pivotal role of PPARγ on mESC self-renewal depends on the presence and absence of LIF.


Assuntos
Proliferação de Células , Células-Tronco Embrionárias/fisiologia , Fator Inibidor de Leucemia/fisiologia , PPAR gama/fisiologia , Anilidas/farmacologia , Animais , Diferenciação Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Células Cultivadas , Proteínas de Homeodomínio/metabolismo , Camundongos , Proteína Homeobox Nanog , PPAR gama/agonistas , PPAR gama/antagonistas & inibidores , Transporte Proteico/efeitos dos fármacos , Rosiglitazona , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Tiazolidinedionas/farmacologia
14.
Avicenna J Med Biotechnol ; 5(1): 2-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23626871

RESUMO

BACKGROUND: The transcription factor Oct-4, is an important marker of undifferentiating level and a key regulating factor for maintenance of pluripotency in cells. Establishment of an Oct-4 promoter-based reporter system is an appropriate tool for monitoring the differentiation of embryonic stem cells both in vivo and in vitro. METHODS: In the present study, we report construction of a recombinant vector, pDB2 Oct4 promoter/EGFP, in which expression of Enhanced Green Fluorescent Protein (EGFP) was controlled by the mouse Oct-4 promoter. RESULTS: In transfected mouse embryonic stem cells with this vector, EGFP was predicted to be specifically expressed in pluripotency state. After transfection, high-level expression of EGFP under the control of Oct-4 promoter was observed in manipulated embryonic stem cells. CONCLUSION: Thus, our new cellular reporter showed that both the properties of embryonic cells and expression the EGFP could be of great help in studying the differentiating and reprogramming mechanisms of mESCs.

15.
Ann Clin Lab Sci ; 43(1): 76-80, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23462609

RESUMO

Rhizomelic Chondrodysplasia Punctata (RCDP) type 1 is a peroxisomal biogenesis disorder with a genetic abnormality in PEX7 gene. In the present study, mutational analysis was performed on two Iranian RCDP patients with distinct clinical phonotype. Mutation detection was carried out by sequencing of RT-PCR product consisting the whole length of PEX7 cDNA. Sequence data revealed the same missense homozygous mutation of G to A at nucleotide 257 in exon3 of PEX7 coding sequence in both patients. Moreover, genomic analysis of the PEX7 gene confirmed the RT-PCR data. This mutation caused one amino acid residue substitution of Cys to Tyr at codon 86 located on WD1 repeat domain region of Pex7p, which severely affected the functionality of PEX7 protein. Back-transfection of vector encoding mutant Pex7p did not restore the normal peroxisomal function in RCDP patient's fibroblast cells dissimilar to the native type of PEX7.


Assuntos
Substituição de Aminoácidos/genética , Condrodisplasia Punctata Rizomélica/genética , Homozigoto , Mutação/genética , Receptores Citoplasmáticos e Nucleares/genética , Acetil-CoA C-Aciltransferase/metabolismo , Sequência de Bases , Pré-Escolar , Análise Mutacional de DNA , Feminino , Humanos , Lactente , Masculino , Dados de Sequência Molecular , Proteínas Mutantes/metabolismo , Linhagem , Receptor 2 de Sinal de Orientação para Peroxissomos
16.
J Res Med Sci ; 17(6): 513-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23626625

RESUMO

CONTEXT: Cutaneous leishmaniasis (CL) is a public health problem in several endemic countries. Recent studies on mouse model and also a few clinical experiments showed that the type of immune response generated at the site of infection and especially balance between regulatory and effector T-cells determines the outcome of the disease toward self-limiting or long-lasting lesions. AIMS: The aim of this study was to evaluate the role of natural regulatory T cells (nTregs) in early and late cutaneous lesions of human Leishmania major (L. major) infection. SETTINGS AND DESIGN: Skin biopsies were collected from parasitologically proven lesions of 28 CL patients, divided into two groups of early and late lesions. The causative agents were identified to be L. major. MATERIALS AND METHODS: Quantitative real-time reverse transcription polymerase chain reaction (PCR) and immunofluorescent staining of biopsies were used to assess the Foxp3 mRNA expression and frequency of nTregs in two groups. Mann-Whitney U test was used to determine the significance of deference between the two groups. RESULTS: Mean relative expressions of Foxp3 mRNA were 0.53 ± 0.23 and 1.26 ± 0.99 in early and late lesions, respectively, which was significantly upper in chronic lesions (P = 0.007). Parallel results were obtained in tissue staining method. CONCLUSIONS: Increased in gene expression and protein staining of nTreg markers in chronic biopsy samples indicates a role for these cells in chronic L. major induced leishmaniasis and supports the effectiveness of regulatory T cell-based immunotherapy for treatment of chronic CL.

17.
Stem Cells Dev ; 21(10): 1794-802, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21970342

RESUMO

Regarding both the neural crest origin and neuronal potential of stem cells from human exfoliated deciduous teeth (SHED), here, we assessed their potential in addition to neural induced SHED (iSHED) for functional recovery when transplanted in a rat model for acute contused spinal cord injury (SCI). Following transplantation, a significant functional recovery was observed in both groups relative to the vehicle and control groups as determined by the open field locomotor functional test. We also observed that animals that received iSHED were in a better state as compared with the SHED group. Immunohistofluorescence evaluation 5 weeks after transplantation showed neuronal and glial differentiation and limited proliferation in both groups. However, myelin basic protein and chondroitin sulfate proteoglycan NG2-oligodendrocyte markers-were increased and glial fibrillary acidic protein-astrocyte marker-was decreased in the iSHED group in comparison with the SHED group. These findings have demonstrated that transplantation of SHED or its derivatives could be a suitable candidate for the treatment of SCI as well as other neuronal degenerative diseases.


Assuntos
Células-Tronco Neurais/transplante , Traumatismos da Medula Espinal/terapia , Transplante de Células-Tronco , Dente Decíduo/citologia , Animais , Diferenciação Celular , Sobrevivência Celular , Células Cultivadas , Fator 2 de Crescimento de Fibroblastos/fisiologia , Humanos , Masculino , Atividade Motora , Células-Tronco Neurais/fisiologia , Ratos , Ratos Wistar , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/patologia , Células-Tronco/fisiologia , Vértebras Torácicas
18.
Stem Cell Res ; 8(1): 120-33, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22099026

RESUMO

Limitations to the in vivo study of human nervous system development make it necessary to design an in vitro model to evaluate the in vivo effects of surrounding tissues on neurogenesis and regional identity of the human neural plate. Rostral neural progenitors (NPs) were initially generated from adherent human embryonic stem cells (hESCs) in a defined condition and characterized. Then, to find the role of somites (S) and notochords (N) in rostro-caudal (RC) and dorso-ventral (DV) patterning of neuronal cells, NPs were co-cultured with microencapsulated chicken S or N in alginate beads. In this study, N induced more neurogenesis as evaluated by expression of TUJ1 and MAP2-positive cells. Additionally, N induced spinal cord ventral brachiothoracic identity as well as NPs proliferation. We observed a synergic effect on motoneuron induction when S and N were used together. Moreover, S induced hindbrain identity in differentiated neuronal cells from NPs. These results indicate that highly enriched NPs can be generated in an adherent and defined system from hESCs. Moreover, S and N tissues highly influenced neuronal differentiation in point of proliferation, neurogenesis, and RC and DV regional identity. These results indicate a very simple and efficient protocol to mimic in vivo events of human neural development in vitro which is important in the context of developmental neuroscience and cellular replacement therapies.


Assuntos
Padronização Corporal , Diferenciação Celular , Células-Tronco Embrionárias/citologia , Células-Tronco Neurais/citologia , Neurônios/citologia , Notocorda/citologia , Somitos/citologia , Animais , Proliferação de Células , Embrião de Galinha , Técnicas de Cocultura , Humanos , Modelos Biológicos , Neurogênese , Fatores de Transcrição/metabolismo
19.
Int J Dev Biol ; 55(3): 321-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21710438

RESUMO

The role of somites and notochords in neuroectoderm differentiation from the embryonic ectoderm and its subsequent patterning into regional compartments along rostro-caudal and dorso-ventral axes, especially in humans, remains elusive. Here, we demonstrate the co-culture effect of somites and notochords isolated from chicken embryos on the neuronal differentiation and regional identity of an adherent culture of human embryonic stem cells (hESCs). Notochord increased the efficiency and speed of neuronal induction, whereas somites had a weak neuronal inducing effect on hESCs. However, a synergistic effect was not observed when notochords and somites were used together. Moreover, in somite and notochord co-culture groups, hESCs-derived neuronal cells expressed HOXB4, OTX2, IRX3 and PAX6, indicative of dorsal hindbrain and ventral anterior identities, respectively. Our results reveal the influence of embryonic notochord and somite co-culture in providing neuronal induction as well as rostro-caudal and dorso-ventral regional identity of hESCs-derived neuronal cells. This study provides a model through which in vivo neuronal induction events may be imitated.


Assuntos
Diferenciação Celular , Células-Tronco Embrionárias/citologia , Notocorda/citologia , Somitos/citologia , Animais , Embrião de Galinha , Galinhas , Técnicas de Cocultura , Indução Embrionária/fisiologia , Células-Tronco Embrionárias/metabolismo , Proteínas do Olho/biossíntese , Proteínas do Olho/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/biossíntese , Proteínas de Homeodomínio/genética , Humanos , Placa Neural/embriologia , Notocorda/fisiologia , Fatores de Transcrição Otx/biossíntese , Fatores de Transcrição Otx/genética , Fator de Transcrição PAX6 , Fatores de Transcrição Box Pareados/biossíntese , Fatores de Transcrição Box Pareados/genética , Proteínas Repressoras/biossíntese , Proteínas Repressoras/genética , Transdução de Sinais , Somitos/fisiologia , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética
20.
Int J Dev Biol ; 55(2): 189-95, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21671222

RESUMO

Stem cells from human exfoliated deciduous teeth (SHED) are highly proliferative, clonogenic and multipotent stem cells with a neural crest cell origin. Additionally, they can be collected with minimal invasiveness in comparison with other sources of mesenchymal stem cells (MSCs). Therefore, SHED could be a desirable option for potential therapeutic applications. In this study, SHEDs were established from enzyme-disaggregated deciduous dental pulp obtained from 6 to 9 year-old children. The cells had typical fibroblastoid morphology and expressed antigens characteristic of MSCs, STRO1, CD146, CD45, CD90, CD106 and CD166, but not the hematopoietic and endothelial markers, CD34 and CD31, as assessed by FACS analysis. Differentiation assessment revealed a strong osteogenic and adipogenic potential of SHEDs. In order to further evaluate the in vitro differentiation potential of SHED into neural cells, a simple short time growth factor-mediated induction was used. Immunofluorescence staining and flow cytometric analysis revealed that SHED rapidly expressed nestin and b-III tubulin, and later expressed intermediate neural markers. In addition, the intensity and percentages of nestin and b-III tubulin and mature neural markers (PSA-NCAM, NeuN, Tau, TH, or GFAP) increased significantly following treatment. Moreover, RT-PCR and Western blot analyses showed that the neural markers were strongly up-regulated after induction. In conclusion, these results provide evidence that SHED can differentiate into neural cells by the expression of a comprehensive set of genes and proteins that define neural-like cells in vitro. SHED cells might be considered as new candidates for the autologous transplantation of a wide variety of neurological diseases and neurotraumatic injuries.


Assuntos
Diferenciação Celular , Polpa Dentária/citologia , Células-Tronco Mesenquimais/citologia , Neurônios/citologia , Dente Decíduo/citologia , Biomarcadores , Western Blotting , Proliferação de Células , Células Cultivadas , Criança , Polpa Dentária/embriologia , Humanos , Proteínas de Filamentos Intermediários/biossíntese , Células-Tronco Mesenquimais/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Nestina , Neurônios/metabolismo , Reação em Cadeia da Polimerase , Esfoliação de Dente , Tubulina (Proteína)/biossíntese
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