RESUMO
The ubiquitin-proteasome system (UPS) plays an important role in maintaining cellular homeostasis by degrading a multitude of key regulatory proteins. FBXW11, also known as b-TrCP2, belongs to the F-box family, which targets the proteins to be degraded by UPS. Transcription factors or proteins associated with cell cycle can be modulated by FBXW11, which may stimulate or inhibit cellular proliferation. Although FBXW11 has been investigated in embryogenesis and cancer, its expression has not been evaluated in osteogenic cells. With the aim to explore FBXW11gene expression modulation in the osteogenic lineage we performed molecular investigations in mesenchymal stem cells (MSCs) and osteogenic cells in normal and pathological conditions. In vitro experiments as well as ex vivo investigations have been performed. In particular, we explored the FBXW11 expression in normal osteogenic cells as well as in cells of cleidocranial dysplasia (CCD) patients or osteosarcoma cells. Our data showed that FBXW11 expression is modulated during osteogenesis and overexpressed in circulating MSCs and in osteogenically stimulated cells of CCD patients. In addition, FBXW11 is post-transcriptionally regulated in osteosarcoma cells leading to increased levels of beta-catenin. In conclusion, our findings show the modulation of FBXW11 in osteogenic lineage and its dysregulation in impaired osteogenic cells.
Assuntos
Osteogênese , Osteossarcoma , Ubiquitina-Proteína Ligases , Proteínas Contendo Repetições de beta-Transducina , Humanos , Proteínas Contendo Repetições de beta-Transducina/metabolismo , Diferenciação Celular/genética , Proliferação de Células/genética , Osteogênese/genética , Osteossarcoma/genética , Fatores de Transcrição/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismoRESUMO
The finding of molecules associated with aging is important for the prevention of chronic degenerative diseases and for longevity strategies. MicroRNAs (miRNAs) are post-transcriptional regulators involved in many biological processes and miR-146b-5p has been shown to be involved in different degenerative diseases. However, miR-146b-5p modulation has not been evaluated in mesenchymal stem cells (MSCs) commitment or during aging. Therefore, the modulation of miR-146b-5p in the commitment and differentiation of mesenchymal cells as well as during maturation and aging in zebrafish model were analyzed. In addition, circulating miR-146b-5p was evaluated in human subjects at different age ranges. Thus, the role of physical activity in the modulation of miR-146b-5p was also investigated. To achieve these aims, RT (real-time)-PCR, Western blot, cell transfections, and three-dimensional (3D) culture techniques were applied. Our findings show that miR-146b-5p expression drives MSCs to adipogenic differentiation and increases during zebrafish maturation and aging. In addition, miR-146b-5p expression is higher in females compared to males and it is associated with the aging in humans. Interestingly, we also observed that the physical activity of walking downregulates circulating miR-146b-5p levels in human females and increases the number of chondroprogenitors. In conclusion, miR-146b-5p can be considered an age-related marker and can represent a useful marker for identifying strategies, such as physical activity, aimed at counteracting the degenerative processes of aging.
Assuntos
MicroRNAs , Peixe-Zebra , Animais , Feminino , Humanos , Masculino , Envelhecimento/genética , Exercício Físico , Longevidade , MicroRNAs/genética , Peixe-Zebra/genéticaRESUMO
BACKGROUND: NorthCape4000 (NC4000) is the most participated ultra-endurance cycling race. Eight healthy male Caucasian amateur cyclists were evaluated: (a) before starting the preparation period; (b) in the week preceding NC4000 (after the training period); (c) after NC4000 race, with the aim to identify the effects of ultra-cycling on body composition, aerobic capacity and biochemical parameters as well as on the differentiation of progenitor cells. METHODS: Bioelectrical impedance analysis (BIA) and dual energy x-ray absorptiometry (DEXA) assessed body composition; cardiopulmonary exercise test (CPET) evaluated aerobic capacity. Differentiation of circulating progenitor cells was evaluated by analyzing the modulation in the expression of relevant transcription factors. In addition, in vitro experiments were performed to investigate the effects of sera of NC4000 participants on adipogenesis and myogenesis. The effects of NC4000 sera on Sestrins and Sirtuin modulation and the promotion of brown adipogenesis in progenitor cells was investigated as well. Two-tailed Student's paired-test was used to perform statistical analyses. RESULTS: We observed fat mass decrease after training as well as after NC4000 performance; we also recorded that vitamin D and lipid profiles were affected by ultra-cycling. In addition, our findings demonstrated that post-NC4000 participant's pooled sera exerted a positive effect in stimulating myogenesis and in inducing brown adipogenesis in progenitor cells. CONCLUSIONS: The training program and Ultra-cycling lead to beneficial effects on body composition and biochemical lipid parameters, as well as changes in differentiation of progenitor cells, with significant increases in brown adipogenesis and in MYOD levels.
Assuntos
Composição Corporal , Lipídeos , Absorciometria de Fóton , Impedância Elétrica , Humanos , MasculinoRESUMO
RUNX2 and SOX9 are two pivotal transcriptional regulators of chondrogenesis. It has been demonstrated that RUNX2 and SOX9 physically interact; RUNX2 transactivation may be inhibited by SOX9. In addition, RUNX2 exerts reciprocal inhibition on SOX9 transactivity. Epigenetic control of gene expression plays a major role in the alternative differentiation fates of stem cells; in particular, it has been reported that SOX9 can promote the expression of miRNA (miR)-204. Our aim was therefore to investigate the miR-204-5p role during chondrogenesis and to identify the relationship between this miR and the transcription factors plus downstream genes involved in chondrogenic commitment and differentiation. To evaluate the role of miR-204 in chondrogenesis, we performed in vitro transfection experiments by using Mesenchymal Stem Cells (MSCs). We also evaluated miR-204-5p expression in zebrafish models (adults and larvae). By silencing miR-204 during the early differentiation phase, we observed the upregulation of SOX9 and chondrogenic related genes compared to controls. In addition, we observed the upregulation of COL1A1 (a RUNX2 downstream gene), whereas RUNX2 expression of RUNX2 was slightly affected compared to controls. However, RUNX2 protein levels increased in miR-204-silenced cells. The positive effects of miR204 silencing on osteogenic differentiation were also observed in the intermediate phase of osteogenic differentiation. On the contrary, chondrocytes' maturation was considerably affected by miR-204 downregulation. In conclusion, our results suggest that miR-204 negatively regulates the osteochondrogenic commitment of MSCs, while it positively regulates chondrocytes' maturation.
Assuntos
Condrogênese/genética , MicroRNAs/genética , Animais , Diferenciação Celular/genética , Células Cultivadas , Condrócitos/fisiologia , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Regulação para Baixo/genética , Humanos , Células-Tronco Mesenquimais/fisiologia , Osteogênese/genética , Fatores de Transcrição SOX9/genética , Células-Tronco/fisiologia , Ativação Transcricional/genética , Regulação para Cima/genética , Peixe-ZebraRESUMO
Autophagy is involved in different degenerative diseases and it may control epigenetic modifications, metabolic processes, stem cells differentiation as well as apoptosis. Autophagy plays a key role in maintaining the homeostasis of cartilage, the tissue produced by chondrocytes; its impairment has been associated to cartilage dysfunctions such as osteoarthritis (OA). Due to their location in a reduced oxygen context, both differentiating and mature chondrocytes are at risk of premature apoptosis, which can be prevented by autophagy. AutophagomiRNAs, which regulate the autophagic process, have been found differentially expressed in OA. AutophagomiRNAs, as well as other regulatory molecules, may also be useful as therapeutic targets. In this review, we describe and discuss the role of autophagy in OA, focusing mainly on the control of autophagomiRNAs in OA pathogenesis and their potential therapeutic applications.
Assuntos
Autofagia/fisiologia , Osteoartrite/tratamento farmacológico , Osteoartrite/patologia , Animais , Autofagia/efeitos dos fármacos , Diferenciação Celular , Senescência Celular/efeitos dos fármacos , Condrócitos/citologia , Condrócitos/fisiologia , Modelos Animais de Doenças , Humanos , MicroRNAs , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Cleidocranial dysplasia (CCD), a dominantly inherited skeletal disease, is characterized by a variable phenotype ranging from dental alterations to severe skeletal defects. Either de novo or inherited mutations in the RUNX2 gene have been identified in most CCD patients. Transcription factor RUNX2, the osteogenic master gene, plays a central role in the commitment of mesenchymal stem cells to osteoblast lineage. With the aim to analyse the effects of RUNX2 mutations in CCD patients, we investigated RUNX2 gene expression and the osteogenic potential of two CCD patients' cells. In addition, with the aim to better understand how RUNX2 mutations interfere with osteogenic differentiation, we performed string analyses to identify proteins interacting with RUNX2 and analysed p53 expression levels. Our findings demonstrated for the first time that, in addition to the alteration of downstream gene expression, RUNX2 mutations impair p53 expression affecting osteogenic maturation. In conclusion, the present work provides new insights into the role of RUNX2 mutations in CCD patients and suggests that an in-depth analysis of the RUNX2-associated gene network may contribute to better understand the complex molecular and phenotypic alterations in mutant subjects.
Assuntos
Displasia Cleidocraniana/genética , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Mutação/genética , Proteína Supressora de Tumor p53/genética , Sequência de Aminoácidos , Sequência de Bases , Diferenciação Celular/genética , Criança , Feminino , Redes Reguladoras de Genes/genética , Humanos , Masculino , Osteoblastos/fisiologia , Osteogênese/genéticaRESUMO
RUNX2, a master osteogenic transcript ion factor, is overexpressed in several cancer cells; in melanoma it promotes cells migration and invasion as well as neoangiogenesis. The annual mortality rates related to metastatic melanoma are high and novel agents are needed to improve melanoma patients' survival. It has been shown that lectins specifically target malignant cells since they present the Thomsen-Friedenreich antigen. This disaccharide is hidden in normal cells, while it allows selective lectins binding in transformed cells. Recently, an edible lectin named BEL ß-trefoil has been obtained from the wild mushroom Boletus edulis. Our previous study showed BEL ß-trefoil effects on transcription factor RUNX2 downregulation as well as on the migration ability in melanoma cells treated in vitro. Therefore, to better understand the role of this lectin, we investigated the BEL ß-trefoil effects in a zebrafish in vivo model, transplanted with human melanoma cells expressing RUNX2. Our data showed that BEL ß-trefoil is able to spread in the tissues and to reduce the formation of metastases in melanoma xenotransplanted zebrafish. In conclusion, BEL ß-trefoil can be considered an effective biomolecule to counteract melanoma disease.
Assuntos
Antineoplásicos/farmacologia , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Proteínas Fúngicas/farmacologia , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Fatores Trefoil/farmacologia , Animais , Antineoplásicos/metabolismo , Basidiomycota/química , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Clonagem Molecular , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Embrião não Mamífero , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Humanos , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Melanócitos/patologia , Melanoma/genética , Melanoma/metabolismo , Melanoma/patologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Fatores Trefoil/genética , Fatores Trefoil/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Peixe-ZebraRESUMO
Bisphosphonates are well known inhibitors of osteoclast activity and thus may be employed to influence osteoblast activity. The present study was designed to evaluate the in vivo effects of zoledronic acid (ZA) on the proliferation and osteoblastic commitment of mesenchymal stem cells (MSC) in osteoporotic patients. We studied 22 postmenopausal osteoporotic patients. Densitometric, biochemical, cellular and molecular data were collected before as well as after 6 and 12 months of ZA treatment. Peripheral blood MSC-like cells were quantified by colony-forming unit fibroblastic assay; their osteogenic differentiation potential was evaluated after 3 and 7 days of induction, respectively. Circulating MSCs showed significantly increased expression levels of osteoblastic marker genes such as Runt-related transcription factor 2 (RUNX2), and Osteonectin (SPARC) during the 12 months of monitoring time. Lumbar bone mineral density (BMD) variation and SPARC gene expression correlated positively. Bone turnover marker levels were significantly lowered after ZA treatment; the effect was more pronounced for C terminal telopeptide (CTX) than for Procollagen Type 1 N-Terminal Propeptide (P1NP) and bone alkaline phosphatase (bALP). Our findings suggest a discrete anabolic activity supported by osteogenic commitment of MSCs, consequent to ZA treatment. We confirm its anabolic effects in vivo on osteogenic precursors.
Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/uso terapêutico , Imidazóis/uso terapêutico , Osteogênese/efeitos dos fármacos , Osteoporose Pós-Menopausa/tratamento farmacológico , Idoso , Conservadores da Densidade Óssea/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Difosfonatos/farmacologia , Feminino , Humanos , Imidazóis/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Pessoa de Meia-Idade , Osteonectina/genética , Osteoporose Pós-Menopausa/genética , Regulação para Cima/efeitos dos fármacos , Ácido ZoledrônicoRESUMO
Osteoarthritis (OA), the most prevalent musculoskeletal pathology, is mainly characterized by the progressive degradation of articular cartilage due to an imbalance between anabolic and catabolic processes. Consequently, OA has been associated with defects in the chondrocitic differentiation of progenitor stem cells (PSCs). In addition, SOX9 is the transcription factor responsible for PSCs chondrogenic commitment. To evaluate the effects of the non-amino bisphosphonate clodronate in OA patients we investigated SOX9 gene expression in circulating progenitor cells (CPCs) and in an in vitro OA model. We evaluated pain intensity, mental and physical performance in OA patients, as well as serum biomarkers related to bone metabolism. In addition, in order to improve therapeutic strategies, we assayed nanoparticle-embedded clodronate (NPs-clo) in an in vitro model of chondrogenic differentiation. Our data showed upregulation of SOX9 gene expression upon treatment, suggesting an increase in chondrocytic commitment. Clodronate also reduced osteoarticular pain and improved mental and physical performance in patients. Furthermore, NPs-clo stimulated SOX9 expression more efficaciously than clodronate alone. Clodronate may therefore be considered a good therapeutic tool against OA; its formulation in nanoparticles may represent a promising challenge to counteract cartilage degeneration.
Assuntos
Ácido Clodrônico/uso terapêutico , Osteoartrite/tratamento farmacológico , Idoso , Biomarcadores/sangue , Diferenciação Celular , Células Cultivadas , Condrócitos/citologia , Condrócitos/metabolismo , Condrogênese , Ácido Clodrônico/química , Ácido Clodrônico/farmacologia , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Citocinas/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Nanopartículas/química , Osteoartrite/patologia , Dor/patologia , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Índice de Gravidade de Doença , Células-Tronco/citologia , Células-Tronco/metabolismo , Regulação para Cima/efeitos dos fármacosRESUMO
This review focuses on the osteogenic differentiation of mesenchymal stem cells (MSC), bone formation and turn-over in good and ill skeletal fates. The interacting molecular pathways which control bone remodeling in physiological conditions during a lifelong process are described. Then, alterations of the molecular pathways regulating osteogenesis are addressed. In the aging process, as well as in glucocorticoid-induced osteoporosis, bone loss is caused not only by an unbalanced bone resorption activity, but also by an impairment of MSCs' commitment towards the osteogenic lineage, in favour of adipogenesis. Mutations affecting the expression of key genes involved in the control of bone development occur in several heritable bone disorders. A few examples are described in order to illustrate the pathological consequences of perturbation in different steps of osteogenic commitment, osteoblast maturation, and matrix mineralization, respectively. The involvement of abnormal MSC differentiation in cancer is then discussed. Finally, a brief overview of clinical applications of MSCs in bone regeneration and repair is presented.
Assuntos
Doenças Ósseas/metabolismo , Células-Tronco Mesenquimais/citologia , Osteoblastos/citologia , Osteogênese , Animais , Doenças Ósseas/patologia , Doenças Ósseas/terapia , Regeneração Óssea , Humanos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/metabolismoRESUMO
Stem cells functions are regulated by different factors and non-conding RNAs, such as microRNA. MiRNAsplay an important role in modulating the expression of genes involved in the commitment and differentiation of progenitor cells. MiRNAs are post transcriptional regulators which may be modulated by physical exercise. MiRNAs, by regulating different signaling pathways, play an important role in myogenesis as well as in muscle activity. MiRNAs quantification may be considered for evaluating physical performance or muscle recovery. With the aim to identify specific miRNAs potentially involved in myogenesis and modulated by physical activity, we investigated miRNAs expression following physical performance in Peripheral Blood Mononuclear Cells (PBMCs) and in sera of half marathon (HM) runnners. The effect of runners sera on Myogenesis in in vitro cellular models was also explored. Therefore, we performed Microarray Analysis and Real Time PCR assays, as well as in vitro cell cultures analysis to investigate myogenic differentiation. Our data demonstrated gender-specific expression patterns of PBMC miRNAs before physical performance. In particular, miR223-3p, miR26b-5p, miR150-5p and miR15-5p expression was higher, while miR7a-5p and miR7i-5p expression was lower in females compared to males. After HM, miR152-3p, miR143-3p, miR27a-3p levels increased while miR30b-3p decreased in both females and males: circulating miRNAs mirrored these modulations. Furthermore, we also observed that the addition of post-HM participants sera to cell cultures exerted a positive effect in stimulating myogenesis. In conclusion, our data suggest that physical activity induces the modulation of myogenesis-associated miRNAs in bothfemales and males, despite the gender-associated different expression of certain miRNAs, Noteworthy, these findings might be useful for evaluating potential targets for microRNA based-therapies in diseases affecting the myogenic stem cells population.
Assuntos
MicroRNAs , Proteína MyoD/metabolismo , Exercício Físico , Feminino , Humanos , Leucócitos Mononucleares/metabolismo , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Desenvolvimento Muscular/genética , MioblastosRESUMO
Flavonoids may modulate the bone formation process. Among flavonoids, fisetin is known to counteract tumor growth, osteoarthritis, and rheumatoid arthritis. In addition, fisetin prevents inflammation-induced bone loss. In order to evaluate its favorable use in osteogenesis, we assayed fisetin supplementation in both in vitro and in vivo models and gathered information on nanoparticle-mediated delivery of fisetin in vitro and in a microfluidic system. Real-time RT-PCR, Western blotting, and nanoparticle synthesis were performed to evaluate the effects of fisetin in vitro, in the zebrafish model, and in ex vivo samples. Our results demonstrated that fisetin at 2.5 µM concentration promotes bone formation in vitro and mineralization in the zebrafish model. In addition, we found that fisetin stimulates osteoblast maturation in cell cultures obtained from cleidocranial dysplasia patients. Remarkably, PLGA nanoparticles increased fisetin stability and, consequently, its stimulating effects on RUNX2 and its downstream gene SP7 expression. Therefore, our findings demonstrated the positive effects of fisetin on osteogenesis and suggest that patients affected by skeletal diseases, both of genetic and metabolic origins, may actually benefit from fisetin supplementation.
RESUMO
Autosomal dominant osteogenesis imperfecta (OI) is caused by mutations in COL1A1 or COL1A2. We identified a dominant missense mutation, c.3235G>A in COL1A1 exon 45 predicting p.G1079S, in a Japanese family with mild OI. As mutations in exon 45 exhibit mild to lethal phenotypes, we tested if disruption of an exonic splicing cis-element determines the clinical phenotype, but detected no such mutations. In the Japanese family, juvenile-onset hyperuricemia cosegregated with OI, but not in the previously reported Italian and Canadian families with c.3235G>A. After confirming lack of a founder haplotype in three families, we analyzed PRPSAP1 and PRPSAP2 as candidate genes for hyperuricemia on chr 17 where COL1A1 is located, but found no mutation. We next resequenced the whole exomes of two siblings in the Japanese family and identified variable numbers of previously reported hyperuricemia-associated SNPs in ABCG2 and SLC22A12. The same SNPs, however, were also detected in normouricemic individuals in three families. We then identified two missense SNVs in ZPBP2 and GPATCH8 on chromosome 17 that cosegregated with hyperuricemia in the Japanese family. ZPBP2 p.T69I was at the non-conserved region and was predicted to be benign by in silico analysis, whereas GPATCH8 p.A979P was at a highly conserved region and was predicted to be deleterious, which made p.A979P a conceivable candidate for juvenile-onset hyperuricemia. GPATCH8 is only 5.8 Mbp distant from COL1A1 and encodes a protein harboring an RNA-processing domain and a zinc finger domain, but the molecular functions have not been elucidated to date.
Assuntos
Hiperuricemia/genética , Proteínas Musculares/genética , Mutação de Sentido Incorreto , Osteogênese Imperfeita/genética , Sequência de Bases , Colágeno Tipo I/genética , Cadeia alfa 1 do Colágeno Tipo I , Proteínas do Ovo/genética , Exoma , Feminino , Haplótipos/genética , Humanos , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Adulto JovemRESUMO
Osteonecrosis of the jaw (ONJ) is a severe clinical condition characterized mostly but not exclusively by an area of exposed bone in the mandible and/or maxilla that typically does not heal over a period of 6-8 weeks. The diagnosis is first of all clinical, but an imaging feedback such as Magnetic Resonance is essential to confirm clinical suspicions. In the last few decades, medication-related osteonecrosis of the jaw (MRONJ) has been widely discussed. From the first case reported in 2003, many case series and reviews have appeared in the scientific literature. Almost all papers concerning this topic conclude that bisphosphonates (BPs) can induce this severe clinical condition, particularly in cancer patients. Nevertheless, the exact mechanism by which amino-BPs would be responsible for ONJ is still debatable. Recent findings suggest a possible alternative explanation for BPs role in this pattern. In the present work we discuss how a condition of osteomalacia and low vitamin D levels might be determinant factors.
Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Conservadores da Densidade Óssea/efeitos adversos , Difosfonatos/efeitos adversos , Osteomalacia/complicações , Deficiência de Vitamina D/complicações , Animais , Humanos , Mandíbula/patologia , Maxila/patologia , Osteomalacia/patologia , Deficiência de Vitamina D/patologiaRESUMO
BACKGROUND: Methylsulfonylmethane (MSM) is a nutraceutical compound which has been indicated to counteract osteoarthritis, a cartilage degenerative disorder. In addition, MSM has also been shown to increase osteoblast differentiation. So far, few studies have investigated MSM role in the differentiation of mesenchymal stem cells (MSCs), and no study has been performed to evaluate its overall effects on both osteogenic and chondrogenic differentiation. These two mutually regulated processes share the same progenitor cells. METHODS: Therefore, with the aim to evaluate the effects of MSM on chondrogenesis and osteogenesis, we analyzed the expression of SOX9, RUNX2, and SP7 transcription factors in vitro (mesenchymal stem cells and chondrocytes cell lines) and in vivo (zebrafish model). Real-time PCR as well Western blotting, immunofluorescence, and specific in vitro and in vivo staining have been performed. Student's paired t test was used to compare the variation between the groups. RESULTS: Our data demonstrated that MSM modulates the expression of differentiation-related genes both in vitro and in vivo. The increased SOX9 expression suggests that MSM promotes chondrogenesis in treated samples. In addition, RUNX2 expression was not particularly affected by MSM while SP7 expression increased in all MSM samples/model analyzed. As SP7 is required for the final commitment of progenitors to preosteoblasts, our data suggest a role of MSM in promoting preosteoblast formation. In addition, we observed a reduced expression of the osteoclast-surface receptor RANK in larvae and in scales as well as a reduced pERK/ERK ratio in fin and scale of MSM treated zebrafish. CONCLUSIONS: In conclusion, our study provides new insights into MSM mode of action and suggests that MSM is a useful tool to counteract skeletal degenerative diseases by targeting MSC commitment and differentiation.
Assuntos
Condrogênese , Peixe-Zebra , Animais , Diferenciação Celular , Células Cultivadas , Condrócitos , Dimetil Sulfóxido/farmacologia , Humanos , Osteoblastos , Osteogênese , SulfonasRESUMO
Farnesyl diphosphate synthetase (FDPS) is a key enzyme in the isoprenoid pathway responsible for cholesterol biosynthesis, post-translational protein modifications and synthesis of steroid hormones, whose expression is regulated by phorbol esters and polyunsaturated fatty acids. Genomic comparison of the 5' upstream sequence of the FDPS genes identifies conserved binding sites for NF-Y, SP1, SRE3, and YY1 regulatory elements in rat, mouse, dog and chimpanzee. Two additional specific consensus sequences, upstream of the core promoter that had not been analysed previously, are shared only by human and chimpanzee genomes. The work presented here aimed at characterizing these genomic sequence elements in the human FDPS promoter region and their contribution to gene expression. We have characterized functionally the minimal basal promoter of the human FDPS gene by means of deletion mutants and we have identified two cis-acting elements which modulate the FDPS gene expression and are recognized by Pax5 and OCT-1 transcription factors.
Assuntos
Regiões 5' não Traduzidas/genética , Regulação Enzimológica da Expressão Gênica , Geraniltranstransferase/genética , Geraniltranstransferase/metabolismo , Regiões Promotoras Genéticas/genética , Animais , Sequência de Bases , Imunoprecipitação da Cromatina , Sequência Conservada , Células HeLa , Humanos , Dados de Sequência Molecular , Fator 1 de Transcrição de Octâmero/metabolismo , Fator de Transcrição PAX5/metabolismo , Alinhamento de SequênciaRESUMO
Regular physical activity is essential for maintaining wellbeing; physical inactivity, on the contrary, is considered by the World Health Organization (WHO) as one of the most important risk factors for global mortality. During physical exercise different growth factors, cytokines and hormones are released, which affect positively the functions of heart, bone, brain and skeletal muscle. It has been reported that physical activity is able to stimulate tissue remodeling. Therefore, in this scenario, it is important to deepen the topic of physical activity-induced effects on stem cells.
Assuntos
Senescência Celular/fisiologia , Exercício Físico/fisiologia , Músculo Esquelético/fisiologia , Células-Tronco/metabolismo , Humanos , Fatores de Risco , Organização Mundial da SaúdeRESUMO
In recent decades, many studies using the zebrafish model organism have been performed. Zebrafish, providing genetic mutants and reporter transgenic lines, enable a great number of studies aiming at the investigation of signaling pathways involved in the osteoarticular system and at the identification of therapeutic tools for bone diseases. In this review, we will discuss studies which demonstrate that many signaling pathways are highly conserved between mammals and teleost and that genes involved in mammalian bone differentiation have orthologs in zebrafish. We will also discuss as human diseases, such as osteogenesis imperfecta, osteoarthritis, osteoporosis and Gaucher disease can be investigated in the zebrafish model.
Assuntos
Doenças Ósseas/metabolismo , Modelos Animais de Doenças , Osteogênese/genética , Transdução de Sinais/genética , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados , Doenças Ósseas/genética , Diferenciação Celular/genética , Expressão Gênica , Humanos , Osteoblastos/metabolismo , Proteínas de Peixe-Zebra/genéticaRESUMO
Alterations in molecular signaling impair cellular functions and induce degenerative diseases. Among the factors affecting intracellular signaling pathways, oxidative stress serves an important role. Astaxanthin (3,3'dihydroxyß, ßcarotene-4,4'dione), a pigment found in aquatic organisms, belongs to the xanthophylls family. Astaxanthin exerts a strong antioxidant activity and is widely used in food, cosmetic and pharmaceutical industries. Oxidative stress damages bone homeostasis by producing reactive oxygen species and increasing the production of proresorption cytokines, such as interleukin (IL)1, tumor necrosis factorα and IL6. Therefore, antioxidant molecules can counteract the negative effects of oxidative stress on bone. Accordingly, previous studies have demonstrated that supplementation of astaxanthin in bone contributes to the restoration of bone homeostasis. The present review summarizes the negative effects of oxidative stress in bone and explores the role of astaxanthin in counteracting skeletal injuries consequent to oxidative stress.
Assuntos
Doenças Ósseas/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Doenças Ósseas/metabolismo , Humanos , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Xantofilas/farmacologia , Xantofilas/uso terapêuticoRESUMO
: Obesity adversely affects bone health by means of multiple mechanisms, e.g., alterations in bone-regulating hormones, inflammation, and oxidative stress. Substantial evidence supports the relationship between adiposity and bone disorders in overweight/obese individuals. It is well known that the balance between mutually exclusive differentiation of progenitor cells into osteoblasts or adipocytes is controlled by different agents, including growth factors, hormones, genetic and epigenetic factors. Furthermore, an association between vitamin D deficiency and obesity has been reported. On the other hand, regular physical activity plays a key role in weight control, in the reduction of obesity-associated risks and promotes osteogenesis. The aim of this review is to highlight relevant cellular and molecular aspects for over-weight containment. In this context, the modulation of progenitor cells during differentiation as well as the role of epigenetics and microbiota in obesity disease will be discussed. Furthermore, lifestyle changes including an optimized diet as well as targeted physical activity will be suggested as strategies for the treatment of obesity disease.