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Skeletal muscle has an outstanding capacity for regeneration in response to injuries, but there are disorders in which this process is seriously impaired, such as sarcopenia. Pharmacological treatments to restore muscle trophism are not available, therefore, the identification of suitable therapeutic targets that could be useful for the treatment of skeletal reduced myogenesis is highly desirable. In this in vitro study, we explored the expression and function of the calcium-sensing receptor (CaSR) in human skeletal muscle tissues and their derived satellite cells. The results obtained from analyses with various techniques of gene and protein CaSR expression and of its secondary messengers in response to calcium (Ca2+) and CaSR drugs have demonstrated that this receptor is not present in human skeletal muscle tissues, neither in the established satellite cells, nor during in vitro myogenic differentiation. Taken together, our data suggest that, although CaSR is a very important drug target in physiology and pathology, this receptor probably does not have any physiological role in skeletal muscle in normal conditions.
Assuntos
Cálcio/metabolismo , Músculo Esquelético/metabolismo , Receptores de Detecção de Cálcio/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Células HEK293 , Humanos , Desenvolvimento Muscular/fisiologia , Mioblastos/metabolismo , Regeneração/fisiologia , Sarcopenia/metabolismo , Células Satélites de Músculo Esquelético/metabolismo , Transdução de Sinais/fisiologiaRESUMO
Telangiectatic osteosarcoma (TOS) is an aggressive variant of osteosarcoma (OS) with distinctive radiographic, gross, microscopic features, and prognostic implications. Despite several studies on OS, we are still far from understanding the molecular mechanisms of TOS. In recent years, many studies have demonstrated not only that microRNAs (miRNAs) are involved in OS tumorigenesis, development, and metastasis, but also that the presence in high-grade types of OS of cancer stem cells (CSCs) plays an important role in tumor progression. Despite these findings, nothing has been described previously about the expression of miRNAs and the presence of CSCs in human TOS. Therefore, we have isolated/characterized a putative CSC cell line from human TOS (TOS-CSCs) and evaluated the expression levels of several miRNAs in TOS-CSCs using real-time quantitative assays. We show, for the first time, the existence of CSCs in human TOS, highlighting the in vitro establishment of this unique stabilized cell line and an identification of a preliminary expression of the miRNA profile, characteristic of TOS-CSCs. These findings represent an important step in the study of the biology of one of the most aggressive variants of OS and the role of miRNAs in TOS-CSC behavior.
Assuntos
Neoplasias Ósseas/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Osteossarcoma/genética , Transcriptoma , Biomarcadores , Biópsia , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Imunofluorescência , Humanos , Imuno-Histoquímica , Osteossarcoma/metabolismo , Osteossarcoma/patologiaRESUMO
Skeletal muscle has remarkable regenerative abilities regulated by a highly orchestrated process involving the activation of cellular and molecular responses, which are dependent on satellite cells. These cells maintain the stem cell population and provide numerous myogenic cells that proliferate, differentiate, fuse and lead to new myofiber formation for a functional contractile tissue. We have isolated and characterized satellite cells obtained from human biopsies and established an in vitro model of myogenesis, evaluating muscle regeneration, monitoring the dynamic increases of the specific myogenic regulatory factors and the final formation of multinucleated myofibers. As the skeletal muscle is an endocrine tissue able of producing many substances that can act on distant organs, and it can be physiologically modulated by a variety of hormones, we embarked in a project of characterization of muscle cell endocrinology machinery. The expression of a large array of hormone receptors was quantified during the process of myogenesis. The results obtained showed a significant and generalized increase of all the tested hormone receptors along the process of differentiation of human cultured cells from myoblasts to myocytes. Interestingly, also the production of the myokine irisin increased in a parallel manner. These findings point to the human cultured myoblasts as an ideal model to characterize the skeletal muscle endocrine machinery and its hormonal regulation.
Assuntos
Desenvolvimento Muscular , Músculo Esquelético/fisiologia , Mioblastos/fisiologia , Diferenciação Celular , Células Cultivadas , Humanos , Fibras Musculares Esqueléticas/fisiologia , Células-TroncoRESUMO
Hyperparathyrodism-jaw tumor (HPT-JT) syndrome is an autosomal dominant disorder. Loss of function of the cell division cycle protein 73 homolog (CDC73) gene is responsible for the syndrome. This gene encodes an ubiquitously expressed 531 amino acid protein, parafibromin, that acts as a tumor suppressor. Loss of heterozygosity (LOH) of the CDC73 locus in many HPT-JT associated parathyroid tumors from patients with germline mutation is in accordance with Knudson's "two-hit" model for hereditary cancer. A 41-year-old man with mandible ossifying fibroma suffered from severe hypercalcemia due to parathyroid carcinoma (PC). Genetic analysis was performed to evaluate germinal and somatic CDC73 gene mutation as well as real-time qRT-PCR to quantify CDC73 mRNA, miR-155 and miR-664 expression levels. Immunohistochemistry and Western blotting (WB) assay were carried out to evaluate parafibromin protein expression. A novel heterozygous nonsense mutation, c.191-192 delT, was identified in the CDC73 gene. No CDC73 LOH was found in PC tissue, nor any differences in expression levels for CDC73 gene, miR-155 and miR-664 between PC and parathyroid adenoma control tissues. On the contrary, both immunohistochemistry and WB assay showed an approximate 90% reduction of parafibromin protein expression in PC. In conclusion, this study describes a novel germinal mutation, c.191-192 delT, in the CDC73 gene. Despite normal CDC73 gene expression, we found a significant decrease in parafibromin. We hypothesize that a gene silencing mechanism, possibly induced by microRNA, could play a role in determining somatic post-transcriptional inactivation of the wild type CDC73 allele.
Assuntos
Adenoma/genética , Carcinoma/genética , Fibroma/genética , Mutação em Linhagem Germinativa , Hiperparatireoidismo/genética , Neoplasias Maxilomandibulares/genética , Neoplasias das Paratireoides/genética , Proteínas Supressoras de Tumor/genética , Adenoma/metabolismo , Adenoma/patologia , Adulto , Alelos , Carcinoma/metabolismo , Carcinoma/patologia , Fibroma/metabolismo , Fibroma/patologia , Humanos , Hiperparatireoidismo/metabolismo , Hiperparatireoidismo/patologia , Imuno-Histoquímica , Neoplasias Maxilomandibulares/metabolismo , Neoplasias Maxilomandibulares/patologia , Perda de Heterozigosidade , Masculino , Neoplasias das Paratireoides/metabolismo , Neoplasias das Paratireoides/patologia , Proteínas Supressoras de Tumor/metabolismoRESUMO
Adipose-derived stem/stromal cells (ASCs), together with adipocytes, vascular endothelial cells, and vascular smooth muscle cells, are contained in fat tissue. ASCs, like the human bone marrow stromal/stem cells (BMSCs), can differentiate into several lineages (adipose cells, fibroblast, chondrocytes, osteoblasts, neuronal cells, endothelial cells, myocytes, and cardiomyocytes). They have also been shown to be immunoprivileged, and genetically stable in long-term cultures. Nevertheless, unlike the BMSCs, ASCs can be easily harvested in large amounts with minimal invasive procedures. The combination of these properties suggests that these cells may be a useful tool in tissue engineering and regenerative medicine.
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The complete repair of periodontal structures remains an exciting challenge that prompts researchers to develop new treatments to restore the periodontium. Recent research has suggested strontium ion to be an attractive candidate to improve osteogenic activity. In this study, we have isolated a clonal finite cell line derived from human periodontal ligament (PDL) in order to assess whether and in which way different doses of SrCl2 (from 0.5 to 500 µg/ml) can influence both the proliferation and the mineralization process, for future application in oral diseases. PDL cells were cloned by dilution plating technique and characterized by FACS. Cell proliferation analysis and mineralization were performed by [3H]-thymidine incorporation and spectrofluorometric assay. Results have evidenced that the higher SrCl2 concentrations tested, from 25 to 500 µg/ml, have increased the proliferation activity after only 24 h of treatment. Interestingly, the same higher concentrations have decreased the mineralization, which was conversely increased by the lower ones, from 0.5 to 10 µg/ml. Our findings suggest the possible use of SrCl2 in appropriate delivery systems that release, at different time points, the specific dose, depending on the biological response that we want to induce on periodontal ligament stem cells, providing a more efficient periodontal regeneration.
RESUMO
BACKGROUND: All implant compounds undergo an electrochemical process when in contact with biological fluids, as well as mechanical corrosion due to abrasive wear, with production of metal debris that may inhibit repair processes. None of the commonly-used methods can diagnose implant allergies when used singly, therefore a panel of tests should be performed on allergic patients as pre-operative screening, or when a postoperative metal sensitisation is suspected. METHODS: We analysed patients with painful prostheses and subjects prone to allergies using the Patch Test in comparison with the Lymphocyte Transformation Test. Cytokine production was evaluated to identify prognostic markers for early diagnosis of aseptic loosening. Metal debris endocytosis and cytoskeletal rearrangement was visualised by confocal microscopy. RESULTS: Our results demonstrate that the Lymphocyte Transformation Test can identify patients who have a predisposition to develop allergic reactions and can confirm the diagnosis of hypersensitivity in patients with painful prostheses. The prevalence of a Th2-cytokine pattern may be used to identify predisposition to the development of allergic diseases, while the selective presence of osteoclastogenic cytokines may be used as predictor of a negative outcome in patients with painful prosthesis. The hypothesis of the prognostic value of these cytokines as early markers of aseptic loosening is attractive, but its confirmation would require extensive testing. CONCLUSIONS: The Lymphocyte Transformation Test is the most suitable method for testing systemic allergies. We suggest that the combined use of the Patch Test and the Lymphocyte Transformation Test, associated with cytokine detection in selected patients, could provide a useful tool for preventive evaluation of immune reactivity in patients undergoing primary joint replacement surgery, and for clinical monitoring of the possible onset of a metal sensitization in patients with implanted devices.
Assuntos
Artroplastia do Joelho/efeitos adversos , Hipersensibilidade/diagnóstico , Metais/efeitos adversos , Complicações Pós-Operatórias/diagnóstico , Próteses e Implantes/efeitos adversos , Artroplastia do Joelho/instrumentação , Biomarcadores/sangue , Citocinas/sangue , Citoesqueleto/ultraestrutura , Endocitose , Feminino , Humanos , Hipersensibilidade/sangue , Hipersensibilidade/etiologia , Ativação Linfocitária , Masculino , Microscopia Confocal , Dor/etiologia , Medição da Dor , Testes do Emplastro , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/etiologia , Falha de Prótese , Células Th2/metabolismoRESUMO
Bone tissue engineering and nanotechnology enable the design of suitable substitutes to restore and maintain the function of human bone tissues in complex fractures and other large skeletal defects. Long-term stability and functionality of prostheses depend on integration between bone cells and biocompatible implants. Human adipose tissue-derived mesenchymal stem cells (hAMSCs) have been shown to possess the same ability to differentiate into osteoblasts and to produce bone matrix of classical bone marrow derived stem cells (BMMSCs). Ti6A14V and Ti13Nb13Zr are two different biocompatible titanium alloys suitable for medical bone transplantation. Preliminary results from our Research Group demonstrated that smooth Ti6Al4V surfaces exhibit an osteoconductive action on hAMSCs, granting their differentiation into functional osteoblasts and sustaining bone matrix synthesis and calcification. The purpose of this study is to assay the ability of nanostructured Ti6Al4V and Ti13Nb13Zr alloys to preserve the growth and adhesion of hAMSCs and, mostly, to sustain and maintain their osteogenic differentiation and osteoblast activity. The overall results showed that both nanostructured titanium alloys are capable of sustaining cell adhesion and proliferation, to promote their differentiation into osteoblast lineage, and to support the activity of mature osteoblasts in terms of calcium deposition and bone extracellular matrix protein production.
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Parathyroid hormone (PTH) is a hormone secreted by the parathyroid glands. Despite its well-known characterized anabolic and catabolic actions on the skeleton, the in vitro effects of PTH on skeletal muscle cells are limited and generally performed on animal models. The aim of this study was to evaluate the effects of a short impulse of PTH (1-84) on the proliferation and the differentiation of skeletal muscle satellite cells isolated from human biopsies. The cells were exposed for 30 min to different concentrations of PTH (1-84), from 10-6 mol/L to 10-12 mol/L. ELISA was used to assay cAMP and the myosin heavy-chain (MHC) protein. The proliferation was assayed by BrdU and the differentiation by RealTime-qPCR. A statistical analysis was performed by ANOVA followed by Bonferroni's test. No significant variations in cAMP and the proliferation were detected in the isolated cells treated with PTH. On the other hand, 10-7 mol/L PTH on differentiated myotubes has shown significant increases in cAMP (p ≤ 0.05), in the expression of myogenic differentiation genes (p ≤ 0.001), and in the MHC protein (p ≤ 0.01) vs. untreated controls. This work demonstrates for the first time the in vitro effects of PTH (1-84) on human skeletal muscle cells and it opens new fields of investigation in muscle pathophysiology.
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Several recent studies have demonstrated that the direct precursor of vitamin D3, the calcifediol [25(OH)D3], through the binding to the nuclear vitamin D receptor (VDR), is able to regulate the expression of many genes involved in several cellular processes. Considering that itself may function as a VDR ligand, although with a lower affinity, respect than the active form of vitamin D, we have assumed that 25(OH)D3 by binding the VDR could have a vitamin's D3 activity such as activating non-genomic pathways, and in particular we selected mesenchymal stem cells derived from human adipose tissue (hADMSCs) for the in vitro assessment of the intracellular Ca2+ mobilization in response to 25(OH)D3. Our result reveals the ability of 25(OH)D3 to activate rapid, non-genomic pathways, such as an increase of intracellular Ca2+ levels, similar to what observed with the biologically active form of vitamin D3. hADMSCs loaded with Fluo-4 AM exhibited a rapid and sustained increase in intracellular Ca2+ concentration as a result of exposure to 10-5 M of 25(OH)D3. In this work, we show for the first time the in vitro ability of 25(OH)D3 to induce a rapid increase of intracellular Ca2+ levels in hADMSCs. These findings represent an important step to better understand the non-genomic effects of vitamin D3 and its role in endocrine system.
Assuntos
Calcifediol/farmacocinética , Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Vitaminas/farmacocinética , Humanos , Técnicas In Vitro , Ligantes , Células-Tronco Mesenquimais , Receptores de Calcitriol/metabolismoRESUMO
BACKGROUND: The expression of the parathyroid transcription factors, encoded by the genes GATA3, GCM2, and MAFB, persists after parathyroid morphogenesis. This suggests a role of these genes in the regulatory program that governs parathyroid function in the adult. Indeed, these 3 genes form a transcriptional cascade able to activate PTH gene expression. MATERIALS AND METHODS: Adult adenoma parathyroid tissues were put in primary cell culture to evaluate the messenger ribonucleic acid (mRNA) expression of the PTH gene, of the genes involved in the calcium regulatory signaling pathway (CaSR, GNA11, and AP2S1), and of the 3 genes (GATA3, GCM2, and MAFB) involved in the parathyroid morphogenesis in the presence of different extracellular calcium concentrations from 0.1 mM to 3.0 mM. AIM: The aim of the study was to investigate whether different extracellular calcium conditions could control the expression of transcription factors critical for parathyroid embryogenesis. RESULTS: The results of the experiments showed that the mRNA expression of GATA3, GCM2, and MAFB genes follows the same response as the PTH gene to extracellular calcium concentrations, with the highest expression at low calcium (0.1 mM) and the lowest at high calcium (3.0 mM). Conversely, the genes involved in the calcium signaling in the parathyroid cells showed a variable response to the extracellular calcium concentrations, with the CaSR and GNA11 genes exhibiting a sensitivity to low calcium concentrations. CONCLUSIONS: These findings indicate that transcription factors recognized for their role in parathyroid embryogenesis show a response to extracellular calcium later in adulthood that parallels the behavior of the PTH gene.
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Long-term stability of arthroplasty prosthesis depends on the integration between the bone tissue and the implanted biomaterials, which requires the contribution of osteoblastic precursors and their continuous differentiation into the osteoblastic phenotype. Classically, these interactions are tested in vitro using mesenchymal stem cells (MSCs) isolated and ex vivo expanded from bone marrow aspirates. Human adipose tissue-derived stromal cells (AMSCs) may be a more convenient source of MSCs, according to their abundance and accessibility, but no data are available on their in vitro interactions with hard biomaterials. The aim of this work is to compare the osteogenic potential of human AMSCs and bone marrow-derived MSCs (BMMSCs) and to evaluate their response to Ti6Al4V alloy in terms of adhesion, proliferation and differentiation features, using the human osteosarcoma cell line SaOS-2 for comparison. The overall results showed that AMSCs have the same ability to produce bone matrix as BMMSCs and that Ti6Al4V surfaces exhibit an osteoinductive action on AMSCs, promoting their differentiation into functional osteoblasts and increasing bone formation. In conclusion, adipose tissue is a promising autologous source of osteoblastic cells with important clinical implications for bone tissue engineering.
Assuntos
Diferenciação Celular , Células-Tronco Mesenquimais/citologia , Titânio , Actinas/metabolismo , Idoso , Ligas , Biomarcadores , Células da Medula Óssea/citologia , Adesão Celular , Forma Celular , Sobrevivência Celular , Células Cultivadas , Citoesqueleto/metabolismo , Humanos , Masculino , Células-Tronco Mesenquimais/metabolismo , Pessoa de Meia-Idade , Osteoblastos/metabolismo , RNA Mensageiro/genética , Propriedades de SuperfícieRESUMO
A hydroxytyrosol (HTyr)-enriched fraction containing HTyr 6% w/w, derived from Olea europaea L. byproducts and obtained using an environmentally and economically sustainable technology, was lipophilized under green chemistry conditions. The effects of three fractions containing hydroxytyrosyl butanoate, octanoate, and oleate, named, respectively, lipophilic fractions 5, 6, and 7, and unreacted HTyr on the human colon cancer cell line HCT8-ß8 engineered to overexpress estrogen receptor ß (ERß) were evaluated and compared to those of pure HTyr. The experimental data demonstrated that HTyr and all fractions showed an antiproliferative effect, as had been observed by the evaluation of the cellular doubling time under these different conditions (mean control, 32 ± 4 h; HTyr 1, 65 ± 9 h; fraction 5, 64 ± 11 h; fraction 6, 62 ± 14 h; fraction 7, 133 ± 30 h). As evidenced, fraction 7 containing hydroxytyrosyl oleate showed the highest activity. These results were related to the link with ER-ß, which was assessed through simultaneous treatment with an inhibitor of ERß.
Assuntos
Olea/química , Álcool Feniletílico/análogos & derivados , Extratos Vegetais/farmacologia , Resíduos/análise , Linhagem Celular Tumoral , Neoplasias Colorretais/fisiopatologia , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Humanos , Estrutura Molecular , Álcool Feniletílico/química , Álcool Feniletílico/farmacologia , Extratos Vegetais/químicaRESUMO
Osteosarcoma (OSA) is the most common primary malignant bone tumor, usually arising in the long bones of children and young adults. There are different subtypes of OSA, among which we find the conventional OS (also called medullary or central osteosarcoma) which has a high grade of malignancy and an incidence of 80%. There are different subtypes of high grade OS like chondroblastic, fibroblastic, osteoblastic, telangiectatic, and the small cell osteosarcoma (SCO). In this study, for the first time, we have isolated, established, and characterized a cell line of cancer stem cells (CSCs) from a human SCO. First of all, we have established a primary finite cell line of SCO, from which we have isolated the CSCs by the sphere formation assay. We have proved their in vitro mesenchymal and embryonic stem phenotype. Additionally, we have showed their neoplastic phenotype, since the original tumor bulk is a high grade osteosarcoma. This research demonstrates the existence of CSCs also in human primary SCO and highlights the establishment of this particular stabilized cancer stem cell line. This will represent a first step into the study of the biology of these cells to discover new molecular targets molecules for new incisive therapeutic strategies against this highly aggressive OSA.
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The current improvements in therapy against osteosarcoma (OS) have prolonged the lives of cancer patients, but the survival rate of five years remains poor when metastasis has occurred. The Cancer Stem Cell (CSC) theory holds that there is a subset of tumor cells within the tumor that have stem-like characteristics, including the capacity to maintain the tumor and to resist multidrug chemotherapy. Therefore, a better understanding of OS biology and pathogenesis is needed in order to advance the development of targeted therapies to eradicate this particular subset and to reduce morbidity and mortality among patients. Isolating CSCs, establishing cell cultures of CSCs, and studying their biology are important steps to improving our understanding of OS biology and pathogenesis. The establishment of human-derived OS-CSCs from biopsies of OS has been made possible using several methods, including the capacity to create 3-dimensional stem cell cultures under nonadherent conditions. Under these conditions, CSCs are able to create spherical floating colonies formed by daughter stem cells; these colonies are termed "cellular spheres". Here, we describe a method to establish CSC cultures from primary cell cultures of conventional OS obtained from OS biopsies. We clearly describe the several passages required to isolate and characterize CSCs.
Assuntos
Neoplasias Ósseas , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Osteossarcoma , Humanos , Células-Tronco NeoplásicasRESUMO
Bone tissue engineering is an emerging field, representing one of the most exciting challenges for scientists and clinicians. The possibility of combining mesenchymal stem cells and scaffolds to create engineered tissues has brought attention to a large variety of biomaterials in combination with osteoprogenitor cells able to promote and regenerate bone tissue. Human adipose tissue is officially recognized as an easily accessible source of mesenchymal stem cells (AMSCs), a significant factor for use in tissue regenerative medicine. In this study, we analyze the behavior of a clonal finite cell line derived from human adipose tissue seeded on poly(ε-caprolactone) (PCL) film, prepared by solvent casting. PCL polymer is chosen for its good biocompatibility, biodegradability, and mechanical properties. We observe that AMSCs are able to adhere to the biomaterial and remain viable for the entire experimental period. Moreover, we show that the proliferation process and osteogenic activity of AMSCs are maintained on the biofilm, demonstrating that the selected biomaterial ensures cell colonization and the development of an extracellular mineralized matrix. The results of this study highlight that AMSCs and PCL film can be used as a suitable model to support regeneration of new bone for future tissue engineering strategies.
Assuntos
Tecido Adiposo/citologia , Fenômenos Fisiológicos Celulares/efeitos dos fármacos , Poliésteres/farmacologia , Células-Tronco/citologia , Alicerces Teciduais/química , Linhagem Celular , Humanos , Poliésteres/química , Células-Tronco/química , Engenharia Tecidual/métodosRESUMO
AIM: To investigate the effects of quercetin and genistein on colon cancer cell proliferation and their estrogen receptor ß (ERß) expression. METHODS: Colon cancer cells were stably transfected with a mammalian expression vector to overexpress ERß (HCT8-ß8-expressing cells) or a control vector (HCT8-pSV2neo-expressing cells). The proliferation of these cells was examined after treatment with quercetin or genistein (5-100 µmol/L), or 10 nmol/L 17ß-estradiol (17ß-E2). Cell viability was examined by acridine orange staining following treatments for 48 or 144 h. Effects of quercetin and genistein on ERß transcriptional transactivation were examined by luciferase activity in HCT8-ß8-expressing cells transiently transfected with a pEREtkLUC reporter vector. In addition, the regulation of ERß transcription by phytoestrogens and 17ß-E2 was examined by quantitative polymerase chain reaction. RESULTS: Proliferation of HCT8-ß8-expressing cells was not reduced low doses (5 µmol/L) of quercetin and genistein, while it was reduced at 25-50 µmol/L with an effect similar to 10 nmol/L 17ß-E2. Treatment with doses of phytoestrogens ≥ 75 µmol/L completely blocked cell growth and reduced overall cell counts, however no effects at any dose were observed in HCT8-pSV2neo-expressing cells. These results were supported by viability staining that revealed acridine orange-stained lysosomes with high doses or extended treatment periods. Genistein and quercetin (50 µmol/L) significantly increased ER-responsive luciferase activity similar to 10 nmol/L 17ß-E2 (P < 0.05). Furthermore, genistein and quercetin (50 µmol/L), as well as 10 nmol/L 17ß-E2 significantly increased ERß mRNA levels in HCT8-ß8-expressing cells (P < 0.05). In addition, treatment of HCT8-pSV2neo-expressing cells with 50 µmol/L quercetin or 10 nmol/L 17ß-E2 significantly increased ERß mRNA levels compared to untreated controls (P < 0.05), though the absolute levels were much lower than in HCT8-ß8-expressing cells. CONCLUSION: The antitumorigenic effects of the phytoestrogenic compounds quercetin and genistein on colon cancers cells occur through ERß activity and expression.
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The lack of a continuous cell line of epithelial parathyroid cells able to produce parathyroid hormone (PTH) has hampered the studies on in vitro evaluation of the mechanisms involved in the control of parathyroid cell function and proliferation. The PT-r cell line was first established from rat parathyroid tissue in 1987, but these cells were known to express the parathyroid hormone-related peptide (Pthrp) gene, but not the Pth gene. In an attempt to subclone the PT-r cell line, a rat parathyroid cell strain was isolated and named PTH-C1. During 3 years, in culture, PTH-C1 cells maintained an epithelioid morphology, displaying a diploid chromosome number, a doubling time around 15 h during the exponential phase of growth, and parathyroid functional features. PTH-C1 cell line produces PTH and expresses the calcium sensing receptor (Casr) gene and other genes known to be involved in parathyroid function. Most importantly, the PTH-C1 cells also exhibit an in vitro secretory response to calcium. Altogether these findings indicate the uniqueness of the PTH-C1 cell line as an in vitro model for cellular and molecular studies on parathyroid physiopathology.
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Glândulas Paratireoides/citologia , Glândulas Paratireoides/metabolismo , Hormônio Paratireóideo/metabolismo , Ratos , Animais , Cálcio/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Expressão Gênica/efeitos dos fármacos , Humanos , Hormônio Paratireóideo/genética , Fenótipo , Receptores de Detecção de Cálcio/genética , Receptores de Detecção de Cálcio/metabolismoRESUMO
This study comprised a comprehensive analysis of the glutathione (GSH) redox system during osteogenic differentiation in human osteoblast-like SaOS-2 cells. For the first time, a clear relationship between expression of specific factors involved in bone remodeling and the changes in the GSH/oxidized GSH (GSSG) redox couple induced during the early phases of the differentiation and mineralization process is shown. The findings show that the time course of differentiation is characterized by a decrease in the GSH/GSSG ratio, and this behavior is also related to the expression of osteoclastogenic markers. Maintenance of a high GSH/GSSG ratio due to GSH exposure in the early phase of this process increases mRNA levels of osteogenic differentiation markers and mineralization. Conversely, these events are decreased by a low GSH/GSSG ratio in a reversible manner. Redox regulation of runt-related transcription factor-2 (RUNX-2) activation through phosphorylation is shown. An inverse relationship between RUNX-2 activation and extracellular signal-regulated kinases related to GSH redox potential is observed. The GSH/GSSG redox couple also affects osteoclastogenesis, mainly through osteoprotegerin down-regulation with an increase in the ratio of receptor activator of NF-κB ligand to osteoprotegerin and vice versa. No redox regulation of receptor activator of NF-κB ligand expression was found. These results indicate that the GSH/GSSG redox couple may have a pivotal role in bone remodeling and bone redox-dysregulated diseases. They suggest therapeutic use of compounds that are able to modulate not just the GSH level but the intracellular redox system through the GSH/GSSG redox couple.
Assuntos
Biomarcadores Tumorais/metabolismo , Dissulfeto de Glutationa/metabolismo , Glutationa/metabolismo , Osteoblastos/metabolismo , Acetilcisteína/farmacologia , Western Blotting , Butionina Sulfoximina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Inibidores Enzimáticos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Glutamato-Cisteína Ligase/antagonistas & inibidores , Glutamato-Cisteína Ligase/metabolismo , Glutationa/farmacologia , Humanos , Osteoblastos/efeitos dos fármacos , Osteoblastos/patologia , Osteoclastos/metabolismo , Osteogênese/efeitos dos fármacos , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Oxirredução , Ligante RANK/genética , Ligante RANK/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Commonly, mesenchymal stem cells derived from bone marrow (BMSCs) are mainly utilized in regenerative medicine field. BMSCs are able to differentiate into several lineages, showing immunosuppressive properties, and they are genetically stable in long-term cultures. In the last years, another mesenchymal stem cells population, obtained from adipose tissue, defined adipose-derived stem/stromal cells (ASCs), it is under assessment of scientific research, as alternative to BMSCs. In fact, ASCs show similar capacity to BMSCs, but unlike BMSCs can be harvested more easily with an higher yield and with less invasive manipulation. In this review the abilities of ASCs to differentiate in osteoblasts cells are shown.