جستجوی مقالات مرتبط با کلیدواژه "تمایز" در نشریات گروه "زیست شناسی"

Kidney diseases are an important medical problem worldwide. Since there are limited treatment options for damaged kidneys, stem cell therapy has become an alternative treatment. The aim of present study is to investigate effect of culture medium obtained from mesenchymal stem cells (MSCs-CM) of newborn mice kidneys in percentages of 10, 30 and 50 on differentiation of embryonic stem cells towards kidney epithelial cells. Mesenchymal stem cells were isolated from kidneys of newborn mice, passaged and propagated. Determination of the identity of cells was done using flow cytometry and checking the expression of surface markers CD105, CD29, CD90. In third passage of extracted cells, supernatant culture medium was collected, hESC were cultured and multiplied in the complete culture medium of cells and the differentiation of hES cells into progenitor cells was investigated. The expression of PAX2, ZO1 and CK18 genes was investigated using RT-PCR, expression of CD133, CD24 and CD44 surface markers was investigated using flow cytometry. Flow cytometry results confirmed the mesenchymal nature of the cells. The results of differentiation of hESCs showed that expression of PAX2, ZO1 and CK18 genes increased significantly (p<0.05) in the groups containing supernatant. The results of flow cytometry show an increase in expression of CD133 and CD24 markers in groups containing CM and the expression of CD44 marker in the group containing 50% CM, compared to control group. In general, results showed supernatant culture process of cells has a positive effect on inducing differentiation of human embryonic stem cells into kidney progenitor cells.

 Human dental pulp stem cells (hDPSCs) that closely common origin with ectomesenchymal cells. could be applied as the source of stem cells for treatment of some neurodegenerative diseases. The hDPSCc are capable of differentiating into dopaminergic neurons in presence of appropriate neurotrophic factors and neurosphere technique with regard to fact This study was carried out to assess the differentiation potential of hDPSCc into dopaminergic neurons using neurosphere technique.

 In this study, hDPSCs were isolated from the third molar using mechanical-enzymatic methods. The cells were harvested in a proper condition medium and differentiated into precursor neuronal stem cells and then consequently differentiated into dopaminergic cells in the presence of neuronal induction media including BDNF and GDNF. Cells in each groups were evaluated by immunocytochemistry and RT-PCR assays. In addition, the amount of dopamine released was measured by HPLC.

 Cells treated with differentiation inducer factors exhibited remarkable changes in phenotypic characteristics and neuron like cells were observed. Molecular results showed that pluripotent genes such as Nestin  , Sox2 expression level gradually reduced in the early stages of differentiation process. However, after treatment with neuronal inducers, genes expression level involved in neurogenesis/dopaminergic like DAT ,PITX3,  ,Nurr1 ,TH PITX3 in treated group increased significantly compared to control group. Moreover, immune cytochemistry assay indicated that cells expressing tyrosine hydroxylase (TH) were also detected in treated group. In addition, dopamine release was significantly increased in treated group (P < 0.05).   

 These research findings confirm that the hDPSCs can be differentiated into dopaminergic neurons via neurosphere technique and appropriate inducers.

Cell therapy using mesenchymal stem cells (MSCs) can be a promising tool in regenerative medicine. One of the richest sources of mesenchymal stem cells is fetal bone marrow. Silymarin has strong antioxidant and anti-inflammatory activities with a positive effect on the proliferation of some cells as well as anti-osteoporosis properties. This study aimed to show the effect of silymarin on the differentiation of mesenchymal stem cells derived from the bone marrow of sheep embryos into the osteogenic line.

Mesenchymal stem cells were isolated from the bone marrow of sheep embryos. MTT test was performed to investigate the cytotoxicity of silymarin on cells at different concentrations for 24 and 72 hours. Then, cells in one of 8 groups 1: negative control; 2: treated with 10 μmol/liter silymarin in the usual environment, 3: treated with 20 μmol/liter silymarin in the usual environment, 4: treated with 100 μmol/liter estradiol in the usual environment, 5: positive control, 6: treatment treated with 10 μmol/liter silymarin in the differentiation medium, 7: treated with 20 μmol/liter silymarin in the differentiation medium, 8: treated with 100 μmol/liter in the differentiation medium, were cultured for 21 days. To determine the osteogenic differentiation of cells, the deposition of hydroxyapatite ions was examined using alizarin staining, and also, the amount of ALP enzyme secretion was also measured in the studied groups.

Comparing the average optical absorption of cells at different concentrations between 24 and 72 hours after treatment showed that the average optical absorption of cells at zero concentration of silymarin after 72 hours of treatment decreased in comparison with those treated for 24 hours (P<0.05), but no significant difference was observed in other concentrations (P>0.05). Examining the level of ALP enzyme secretion, 21 days after treatment with silymarin in the studied groups showed that the highest level of enzyme secretion was in group 8 (P≤0.05). The lowest amount of enzyme secretion was observed in group 1 (negative control) and then in group 2 and group 3 respectively (P<0.05). No significant difference was observed between groups 4, 5, and 6 (P>0.05). Based on the alizarin red staining results, calcium ions deposition was observed in all the groups related to the differentiation medium, which increased in groups 8, 7, 6, and 5, respectively. In the groups cultured in the usual environment, there was no calcification in group 1 and the amount of calcification increased in groups 2, 3, and 4, respectively. In total, the amount of calcification in the differentiation environment groups was higher in comparison with the usual environment.

During this study, Silymarin had no toxic effect on the mesenchymal stem cells derived from the bone marrow of sheep embryos in the studied concentrations after 24 and 72 hours of treatment. It increased the differentiation of the cells into the osteogenic lineage in a concentration-dependent manner. Therefore, it seems that with further studies and identification of the molecular pathways of silymarin's effect, it can be used in cell therapy in order to repair bone lesions.

Despite numerous studies on the biological properties and differentiability of umbilical cord-derived mesenchymal stem cells, these studies are still ongoing in order to achieve new findings. Therefore, the present study investigates the biological properties of umbilical cord-derived mesenchymal stem cells and their ability to differentiate into osteocyte and adipocyte.

In this experimental laboratory study, 30 whole placenta specimens were prepared from the mothers under cesarean section and kept under standardized conditions. The mesenchymal cells were isolated by enzymatic method and their morphological characteristics were examined by microscopy and absorption spectroscopy and their biological properties, in particular expression of CD markers, were determined by flow cytometry. Finally, mesenchymal stem cells were cultured in specific media in order to differentiate into osteocyte and adipocyte. Data were analyzed using descriptive statistics.

Morphological and physical examinations by microscope and absorption spectroscopy as well as presenting of CD44, CD73, CD90, and CD105 markers and lacking of CD34 and CD45 markers demonstrated the mesenchymal entity of stem cells. Mesenchymal stem cells successfully differentiated into osteocyte and adipocyte.

Human cord-derived mesenchymal stem cells can differentiate into adult fat and bone cells. In this respect, the use of cord-derived mesenchymal cells could be of significant interest in cell therapy.

In this study, investigated the effect of flavonoid compounds in walnut skin on the production of insulin-secreting cells.

In this experimental study, adipose-derived mesenchymal stem cells (AD- MSCs) were differentiated into insulin-producing cells under sterile conditions for 21 days in the presence of flavonoid extract at doses of 50 and 100 mg/ml. Streptozotocin at a dose of 60 mg/kg was used to diagnose rats. Dithizone staining (DTZ) for insulin, Immunofluorescence to determine the presence of pancreatic beta-specific proteins, Blood glucose measurement by glucometer, Serum creatine, urea and uric acid levels by calorimetry and Reverse chain reaction transcription E- polymerase (RT-PCR) was used to evaluate the expression of PAX4 gene.

AD-MSCs under the above conditions gradually changed from spindle-shaped fibroblasts to circular cells and showed insulin-producing cells using red DTZ dye and insulin secretion .Expression of insulin-pronsulin and beta receptor markers was demonstrated, blood sugar, urea, uric acid and creatinine levels decreased and the expression level of PAX4 gene in experimental groups showed a significant disorder (P≥0.05).

The results showed that AD-MSCs under the flavonoid extract of walnut green skin have the ability to differentiate into insulin-producing cells. Keywords: Mesenchymal stem cells, Insulin-producing cells

The genes controlling meiotic progression in plants and not affecting mitotic progression are most widely studied in maize Zea mays and cruciferous plant Arabidopsis thaliana. These include the genes controlling the differentiation of somatic cells into sporogenous ones and meiosis-initiating genes, genes encoding meiosis-specific proteins of chromosomes and synaptonemal complexes, genes of mediator proteins and enzymes of meiotic DNA recombination and crossover, and genes controlling meiosis-specific behavior of centromeres and the course of two meiotic divisions. A large number of such genes have been cloned and studied at the molecular level. The studies of meiotic genes in rice Oriza sativa are actively developing, while studies of corresponding genes in barley Hordeum vulgare, rye Secale cereale, tomato Solanum lycopersicum, and hexaploid wheat Triticum aestivum are less advanced. To identify meiotic genes, chemical and insertional mutagenesis, genetic and cytological analysis, genomic and proteomic studies, methods of reverse genetics, and bioinformatics are used.

The presence of neural precursor stem cells (NSCs) in some parts of the adult brains and the potency of these types of cells for the acceleration of the proliferation and differentiation processes with a therapeutic viewpoint is another beneficial facet of the application of neural precursor stem cells in cell biology. Quercetin, as an herbal flavonoid, has been extensively investigated and shown to have numerous effects on some cell-lines and disorders. We aimed to investigate the impact of quercetin, on proliferation and differentiation of NSCs derived from the subventricular zone (SVZ) of the adult rat brains. The isolated SVZs were mechanically minced into pieces through repeated pipetting in phosphate-buffered saline, incubated with 0.25% trypsin and treated with trypsin inhibitor; then centrifuged to obtain the cell suspension. The obtained cell suspension was cultured for one week to achieve neurospheres. When the cells reached confluence of 70-80%, they were sub-cultured for three passages and in the third passage, quercetin was treated with the cultured cells at the concentrations of 1, 5, and 15 μM. Methods such as Real time-PCR, MTT assay and ImageJ software, have been used to validate differentiation and proliferation of cells. The results indicated that the differentiation rate of NSCs is affected by various concentrations of quercetin in a dose-dependent manner so that 1µM quercetin had the least, and 15µM quercetin showed the most effects on cell differentiation. However, 1µM quercetin exhibited no significant cell toxicity, the most antiproliferative potential showed when treated with 15µM concentration quercetin.

The SPTBN4 gene, a part of the spectrin protein family, plays important roles in various cellular processes, including cell cycle, nerve cell development, and so on. Recently, a new miRNA has been found in this SPTBN4 gene, which was registered at the NCBI database. The aim of the present study was to investigate the expression of this miRNA, called SPTBN4-miR1, in the process of differentiation of human embryonal carcinoma cell line NT2 and also the overexpression effect of this miRNA on the differentiation of these cells. RT-qPCR results indicate that SPTBN4-miR1-5p and SPTBN4-miR1-3p show a significant increase in expression in the process of neural differentiation from day three until the 8th and 14th day of differentiation. Then, after overexpressing the SPTBN4-miR1 precursor in NT2 cells and retinoic acid treatment, the expression of pluripotent and differentiation revealed the role of SPTBN4-miR1-5p and SPTBN4-miR1-3p in promoting differentiation and exclusion from the pluripotent state. It seems that by making further studies and finding out the possible targets of these miRNAs, a distinctive marker can be achieved and used to improve the differentiation process.

11, 25 dihydroxy vitamin D3, an active metabolite of vitamin­D3 has been reported to inhibit the growth of number neoplasms such as prostate, breast, colorectal, leukemia and skin cancers. Valproic acid, as a potent histone deacetylase inhibitor, also plays an important role in inhibition of proliferation of tumor cells. However, there are no reports so far on the cooperation between valproic acid and vitamin­ D3 for anti-leukemic effect. The goal of the present research was to evaluate whether low doses of vitamin D3 potentiate the toxicity of valproic acid and whether this toxic action is mediated via apoptotic mechanisms. In this study HL-60 cells were treated either with different concentrations of valproic acid and vitamin­ D3 alone and in combination with each other for 24 hours. Cell survival was determined by MTT assay and then Hoechst staining was used to determine the type of death cell. This present study indicates that vitamin ­D3 potentiates the antitumor effects of valproic acid. Also, the results of staining cells showed that valproic acid and vitamin ­D3 induced apoptosis in HL-60 cells. In total, the new combination of valproic acid and vitamin D3 showed synergistic anti-proliferative effect and induced apoptosis on HL-60 cancer cells.

Induced pluripotent cells have been considered as one of the most recent and best cell sources for the cell therapy. In this study, the differentiation potency of human iPS cells, cultured on scaffolds, which can differentiate into definitive endodermal cells as precursor for hepatocytes, pancreatic and lung cells, was studied. Embryoid bodies composed of pluripotent cells, were seeded on electrospinning nanofiber scaffold. The cells were differentiated into definitive endoderm using IDE1. Expression of definitive endoderm markers including Sox17, FoxA2 and GSC were confirmed by immunocytochemistry staining and qRT-PCR analysis. In the present study, morphology and viability of cells were evaluated by utilizing a scanning electron microscopy and MTT assay, respectively. The results demonstrated the positive effect of 3D cultures, using suitable factors, on definitive endoderm differentiation.

Cell-therapy provides a promising alternative for the treatment of type 1 diabetes. One of the most proper candidates is multipotent skin-derived precursors cells (SKPs)، which can be differentiated into insulin producing cells (IPCs). In this study، human skin-derived precursors (hSKPs) were isolated، expanded and differentiated into IPCs in vitro، through exposure to rat pancreatic extract (2 days after a 60% pancreatectomy). In order to differentiation، SKPs were Cultured in DMEM، containing FBS، pancreatic extract and glucose for 14 days. In order to verify insulin production in the cells، dithizone-staining، which is a method for insulin identification، was employed. In addition، insulin expression was examined immunocytochemically، and insulin secretion was examined using enzyme-linked immunosorbent assay. Cellular clusters appeared after approximately 14 days. The clusters were found to be immunoreactive to insulin. Cellular clusters were also able to secrete detectable amounts of insulin in glucose concentration dependent manner. The results of the current study showed that pancreatic extract treatment can differentiate human SKPs into functional IPCs. This may offer a safer cell source for future stem cell-based therapies.

Sea cucumber has been paid attention in treatment of bone defects due to possessing bioactive compound such as chondroitin sulfate. There were done successful researches in the field of application of mesenchymal stem cells for treatment of bone injury recently. Therefore, this study performed to define the osteogenic and adipogenic potency of Persian Gulf sea cucumber alcoholic extract on differentiation rat bone marrow derived stem cells into osteogenic and adipogenic. In this experimental study, bone marrow stromal cells were isolated by flushing from male Wistar rat and demonstrated stemness by immunocytochemistry. The cells in 9 experimental group were exposed to various concentration (3.5, 6.25, 12.5, 25, 50, 10, 200, 400, 800 μg/ml) of sea cucumber alcoholic extract and cytotoxicity of sea cucumber alcoholic extract determined by MTT assay. Eventually, after 21 day, osteogenic and adipogenic differentiation were evaluated with alizarin red, oil red staining and alkalin phosphatase kit. Data were analyzed by SPSS software, ANOVA and the level of p ≤ 0.05 was considered significant. An appropriate dosage for treatment of mesenchymal stem cells was determined less than 50 μg/ml. Also, oil red staining showed that sea cucumber alcoholic extract does not have capacity of adipogenic induction while alizarin red staining and alkaline phosphatase revealed that concentration of 25 μg/ml sea cucumber alcoholic extract was most efficient concentration into osteogenic differentiation. Sea cucumber extract was able to differentiate rat bone marrow mesenchymal stem cells into osteogenic lineage.

Introduction & Biological scaffolds, composed of Extra Cellular Matrix (ECM), are capable of facilitating the restructuring of a large number of tissues. The objective of this study was to investigate the effect of ovine bladder scaffold of sheep, domesticated breedon blastema cells in vitro. At first, ovine bladder o the sheep was decellularized by putting in 1% wt/vol solution of sodium dodecyl sulfate (SDS) for 24 hours. Then to prepare the blastema tissue, the pinna of New Zealand rabbit was manually punched-hole with a special puncher and a circular blastema was separated. There after, the decellularized samples were put in the middle of blastema ring and were transfered to the culture medium. To continue the study, microscope with lights of hematoxylin & eosin and pick indigo and Toluidine blue staining was used. Some samples on the day 15 and 20 of culture were studied by transitional electron microscope. Collagen fibers were preserved after decellularized in matrix of bladder. Most migration of blastema cells occurred on days 15 and 20 of culture. On the day 10 and 15, some immature cells were differentiation in the pathway of adipocyte and fibroblast. On the day 15th and 20th, more blastema cells were migrated to the ovine scaffold. On the 10th and 15 day immature cell culture was seen to be differentiated from fibroblast and adipocyte cells. On the 15 th day blastema cell culture differentiated from covering cells and on the 20th day from fibroblast and adipocyte cells were seen. Bladder scaffold has ability to induce blastema cells and causes not only blastoma cells’ migration but also to be changed to different cells. This phenomenon is very important because of no growth factor and inducer was used in culture medium.

Chromene derivatives are able to growth inhibition and induce apoptosis in different cell types. In this study، we reported a derivative of 4-aryl-4H-chromenes with differentiation and apoptotic activity against NB4، Acute Promyelocytic Leukemia (APL) cell. Matherial and The cells were seeded in 24-well plates at 1×105 cells/well and treated with 1−12 nM of the 2-amino- 4- (3-bromo 4، 5 dimethoxy – phenyl) -3- cyano -7- (dimethylamino) -4H-chromene (3-BMPC). This compound inhibited growth and viability of the cells in dose- and time-dependent manner. 3-BMPC was found to be highly active growth inhibitor with IC50 of 3 nM (72 h) as determined by trypan blue exclusion test. Wright-Giemsa staining and latex particle phagocytosis assay were used to study differentiated cells. Apoptosis was also detected by fluorescent microscope and DNA fragmentation assay. Results indicated that at low concentrations (3 nM) and after 48 h of treatment، NB4 cells were differentiated to monocyte/macrophage lineage. Results of Hoechst 33258 staining also revealed that the compound induced apoptosis at respective IC50 value after 72 h of treatment. Regarding these results، this compound can be proposed as effective agents for more investigation in leukemia treatment

The aim of this study was to compare the morphological and biochemical character of mesenchymal stem cells and osteoblasts in vitro. After extraction of rat bone marrow mesenchymal stem cells and culturing them till the 3rd passage, these cells were cultured in media containing beta-glycerol phosphate, dexamethasone and ascorbic acid for 21 days. Then morphology of the mesenchymal cells and differentiated one were investigated using Hoechst and acridine orange. In addition the level of matrix deposition, level of calcium, activity of alkaline phosphatase in mesenchymal cells and differentiated on as well as metabolic activity of osteoblasts with the help of MTT was determined. Morphological study showed delocalization of nuclei and roundness of cytoplasm in differentiated cells as compared to mesenchymal stem cells. In addition mineralization of the matrix started from the 10th day and reached the maximum level at the 21st day. Also from the day 10 the level of calcium increased significantly (p<0.05) but activity of alkaline phosphatase decreased significantly (p<0.05) in differentiated cells. Where as during the differentiation process the metabolic activity of the cells increased significantly (p<0.05). In addition to morphological differences, calcium content, alkaline phosphatase activity and metabolic activity of the mesenchymal cells and osteoblasts also differs. Therefore in addition to alizarin red staining these factors also can be used to investigate the differentiation processes in vitro.

The aim was to investigate the interactions and cellular behavior of the blastema tissue and natural 3D elastic scaffold in vitro. In this study cows aorta was used as a scaffold. To prepare a very porous elastic scaffold, the cells and collagen were removed by treating that with 50 mg/ml cyanogen bromide in 70% formic acid. The prepared scaffold were then placed inside the blastmea rings and kept in culture media for 40 days. The interaction between blastema tissues and elastic scaffolds were studied in 10 days intervals. Microscopic studies in different day on blastema tissue and scaffold revealed that the cells and collagen fibers were omitted successfully from the elastic scaffold. Moreover, histological studies indicated that the cells had penetrated into the scaffold. In addition cell devision, probable differentiation of blastema cells to fibroblast and myocyte and also angiogenesis due to inductve effect of elastic scaffold were abserved. Our results indicated that, it is possible to prepare a natural elastic scaffold from aorta by treatment with cyanogen bromide. On the other hand, this scaffold may have inductive effects on cell behaviors such as migration, adhesion, cell division and probably differentiation. Further studies are required to confirm the indentity of cells and other properties of the scaffold and also its possible use in engineering of vascular tissue.

Microtubules are important components of cell cytoskeleton which participate in mitosis, protein localization and cell signaling. They are also the targets of several anticancer agents which indicating their importance in maintaining cell viability. Capacity of leukemia cells to re-organize their microtubules is considered an integral part of differentiation of these cells to mature granulocytes by all-trans retinoic acid (ATRA), which is an establish drug for treating acute promyelocytic leukemia. In this study we examined alpha-, alpha-acetylated and gamma-tubulin content, their patterns of distribution in the cytoplasm and the potency of centrosomes in reorganizing microtubules in different stages of ATRA-induced differentiation of HL-60 cell line. Results have shown that gamma-tubulin content was increased with a focal centrosomal accumulation of gamma-tubulin following differentiation. Differentiated cells had the ability to re-organize their microtubule network following nocodazole challenge test, whereas undifferentiated cells did not show such ability. Alpha-tubulin was more regularly organized in differentiated cells and acetylated alpha-tubulin generally followed the same organization patterns after differentiation as occurred for alpha-tubulin. Our results is suggestive of a centrosomal, and organized nucleation pattern of microtubules in HL-60 cells following differentiation possibly mediated through upregulation of gamma-tubulin.