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1.
Mol Pharm ; 18(12): 4322-4330, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34734526

RESUMO

Parathyroid hormone-related protein (PTHrP), which is secreted from a tumor, contributes to the progression of cachexia, a condition that is observed in half of all cancer patients. Although drug clearance was reported to decrease in patients with cancer cachexia, the details have not been clarified. The present study reports on an investigation of whether PTHrP is involved in the alternation of drug metabolism in cases of cancer cachexia. Cancer cachexia model rats with elevated serum PTHrP levels showed a significant decrease in hepatic and intestinal CYP3A2 protein expression. When midazolam, a CYP3A substrate drug, was administered intravenously or orally to the cancer cachexia rats, its area under the curve (AUC) was increased by about 2 and 5 times, as compared to the control group. Accordingly, the bioavailability of midazolam was increased by about 3 times, thus enhancing its pharmacological effect. In vitro experiments using HepG2 cells and Caco-2 cells showed that the addition of serum from cancer cachexia rats or active PTHrP (1-34) to each cell resulted in a significant decrease in the expression of CYP3A4 mRNA. Treatment with a cell-permeable cAMP analog also resulted in a decreased CYP3A4 expression. Pretreatment with protein kinase A (PKA), protein kinase C (PKC), and nuclear factor-kappa B (NF-κB) inhibitors recovered the decrease in CYP3A4 expression that was induced by PTHrP (1-34). These results suggest that PTHrP suppresses CYP3A expression via the cAMP/PKA/PKC/NF-κB pathway. Therefore, it is likely that PTHrP would be involved in the changes in drug metabolism observed in cancer cachexia.


Assuntos
Caquexia/metabolismo , Citocromo P-450 CYP3A/genética , Neoplasias/complicações , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Animais , Células CACO-2 , Células Hep G2 , Humanos , Fígado/enzimologia , Masculino , Midazolam/farmacocinética , NF-kappa B/fisiologia , Proteína Quinase C/fisiologia , Ratos , Ratos Sprague-Dawley
2.
Eur J Endocrinol ; 184(2): 311-320, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33270042

RESUMO

OBJECTIVE: Pseudohypoparathyroidism and related disorders belong to a group of heterogeneous rare diseases that share an impaired signaling downstream of Gsα-protein-coupled receptors. Affected patients may present with various combination of symptoms including resistance to PTH and/or to other hormones, ectopic ossifications, brachydactyly type E, early onset obesity, short stature and cognitive difficulties. Several years ago we proposed a novel nomenclature under the term of inactivating PTH/PTHrP signaling disorders (iPPSD). It is now of utmost importance to validate these criteria and/or improve the basis of this new classification. DESIGN: Retrospective study of a large international series of 459 probands and 85 relatives molecularly characterized. METHODS: Information on major and minor criteria associated with iPPSD and genetic results were retrieved from patient files. We compared the presence of each criteria according to the iPPSD subtype, age and gender of the patients. RESULTS: More than 98% of the probands met the proposed criteria for iPPSD classification. Noteworthy, most patients (85%) presented a combination of symptoms rather than a single sign suggestive of iPPSD and the overlap among the different genetic forms of iPPSD was confirmed. The clinical and molecular characterization of relatives identified familial history as an additional important criterion predictive of the disease. CONCLUSIONS: The phenotypic analysis of this large cohort confirmed the utility of the major and minor criteria and their combination to diagnose iPPSD. This report shows the importance of having simple and easily recognizable signs to diagnose with confidence these rare disorders and supports a better management of patients.


Assuntos
Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Hormônio Paratireóideo/fisiologia , Pseudo-Hipoparatireoidismo/classificação , Pseudo-Hipoparatireoidismo/diagnóstico , Terminologia como Assunto , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Disostoses/classificação , Disostoses/genética , Feminino , França/epidemiologia , Inativação Gênica , Humanos , Lactente , Recém-Nascido , Deficiência Intelectual/classificação , Deficiência Intelectual/genética , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular , Mutação , Ossificação Heterotópica/classificação , Ossificação Heterotópica/genética , Osteocondrodisplasias/classificação , Osteocondrodisplasias/genética , Hormônio Paratireóideo/genética , Proteína Relacionada ao Hormônio Paratireóideo/genética , Pseudo-Hipoparatireoidismo/epidemiologia , Pseudo-Hipoparatireoidismo/genética , Doenças Raras , Estudos Retrospectivos , Transdução de Sinais/genética , Espanha/epidemiologia , Adulto Jovem
3.
J Dent Res ; 99(2): 133-142, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31623502

RESUMO

Tooth eruption is a unique biological process by which highly mineralized tissues emerge into the outer world, and it occurs concomitantly with tooth root formation. These 2 processes have been considered independent phenomena; however, recent studies support the theory that they are indeed intertwined. Dental mesenchymal progenitor cells in the dental follicle lie at the heart of the coupling of these 2 processes, providing a source for diverse mesenchymal cells that support formation of the highly functional tooth root and the periodontal attachment apparatus, while facilitating formation of osteoclasts. These cells are regulated by autocrine signaling by parathyroid hormone-related protein (PTHrP) and its parathyroid hormone/PTHrP receptor PPR. This PTHrP-PPR signaling appears to crosstalk with other signaling pathways and regulates proper cell fates of mesenchymal progenitor cell populations. Disruption of this autocrine PTHrP-PPR signaling in these cells leads to defective formation of the periodontal attachment apparatus, tooth root malformation, and failure of tooth eruption in molars, which essentially recapitulate primary failure of eruption in humans, a rare genetic disorder exclusively affecting tooth eruption. Diversity and distinct functionality of these mesenchymal progenitor cell populations that regulate tooth eruption and tooth root formation are beginning to be unraveled.


Assuntos
Células-Tronco Mesenquimais , Proteína Relacionada ao Hormônio Paratireóideo , Erupção Dentária , Humanos , Osteoclastos , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Receptor Tipo 1 de Hormônio Paratireóideo
4.
Ann Rheum Dis ; 78(4): 551-561, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30745310

RESUMO

OBJECTIVES: Wnt16 is implicated in bone fracture and bone mass accrual both in animals and humans. However, its functional roles and molecular mechanism in chondrocyte differentiation and osteoarthritis (OA) pathophysiology remain largely undefined. In this study, we analysed its mechanistic association and functional relationship in OA progression in chondrocyte lineage. METHODS: The role of Wnt16 during skeletal development was examined by Col2a1-Wnt16 transgenic mice and Wnt16fl/fl;Col2a1-Cre (Wnt16-cKO) mice. OA progression was assessed by micro-CT analysis and Osteoarthritis Research Society International score after anterior cruciate ligament transection (ACLT) surgery with Wnt16 manipulation by adenovirus intra-articular injection. The molecular mechanism was investigated in vitro using 3D chondrocyte pellet culture and biochemical analyses. Histological analysis was performed in mouse joints and human cartilage specimens. RESULTS: Wnt16 overexpression in chondrocytes in mice significantly inhibited chondrocyte hypertrophy during skeletal development. Wnt16 deficiency exaggerated OA progression, whereas intra-articular injection of Ad-Wnt16 markedly attenuated ACLT-induced OA. Cellular and molecular analyses showed that, instead of ß-catenin and calcium pathways, Wnt16 activated the planar cell polarity (PCP) and JNK pathway by interacting mainly with AP2b1, and to a lesser extend Ror2 and CD146, and subsequently induced PTHrP expression through phosphor-Raptor mTORC1 pathway. CONCLUSIONS: Our findings indicate that Wnt16 activates PCP/JNK and crosstalks with mTORC1-PTHrP pathway to inhibit chondrocyte hypertrophy. Our preclinical study suggests that Wnt16 may be a potential therapeutic target for OA treatment.


Assuntos
Artrite Experimental/patologia , Osteoartrite/patologia , Proteínas Wnt/fisiologia , Animais , Artrite Experimental/metabolismo , Artrite Experimental/fisiopatologia , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Diferenciação Celular/fisiologia , Polaridade Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Condrócitos/patologia , Condrócitos/fisiologia , Progressão da Doença , Humanos , Hipertrofia/prevenção & controle , Sistema de Sinalização das MAP Quinases/fisiologia , Alvo Mecanístico do Complexo 1 de Rapamicina/fisiologia , Camundongos Transgênicos , Osteoartrite/metabolismo , Osteoartrite/fisiopatologia , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Proteínas Wnt/deficiência , Proteínas Wnt/metabolismo
5.
Acta Biomed ; 90(4): 510-516, 2019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31910177

RESUMO

BACKGROUND: Parathyroid hormone related peptide (PTHrP) is widely expressed in a variety of normal fetal and adult tissues. AIM OF WORK: Review of these normal physiologic functions of PTHrP in each of these tissues. METHOD: Performed literature search on pubmed on articles related to PTHrP and physiologic roles. RESULTS: PTHrP is expressed in wide range of sites in the body with roles including relaxation of vessels and smooth muscle cells, and regulation of development. PTHrP also mediates humoral hypercalcemia of malignancy. PTHrP can be falsely elevated in benign conditions. Lastly, PTHrP has a pharmacological role in osteoporosis treatment. CONCLUSIONS: PTHrP has many various physiological roles besides mediating humoral hypercalcemia of malignancy. (www.actabiomedica.it).


Assuntos
Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Humanos
7.
Drugs Today (Barc) ; 54(5): 293-303, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29911694

RESUMO

Abaloparatide is a synthetic 34-amino acid peptide analogue of the 1-34 portion of the human parathyroid hormone-related protein (PTHrP). It has been approved in the U.S. for the treatment of postmenopausal women with osteoporosis at a high risk for fracture. Abaloparatide is an anabolic agent and it seems to have a potent anabolic activity with reduced effects on bone resorption. It reduces the risk of vertebral and nonvertebral fractures, major osteoporotic fractures and clinical fractures, with a significant improvement in bone mineral density at femoral neck, total hip and lumbar spine. In this article we summarize the development of the abaloparatide molecule and preclinical and clinical studies published so far. Results from clinical trials indicate that abaloparatide may become an important option for the anabolic treatment of postmenopausal osteoporosis.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Osteoporose Pós-Menopausa/tratamento farmacológico , Proteína Relacionada ao Hormônio Paratireóideo/uso terapêutico , Osso e Ossos/metabolismo , Ensaios Clínicos como Assunto , Feminino , Humanos , Fraturas por Osteoporose/prevenção & controle , Proteína Relacionada ao Hormônio Paratireóideo/efeitos adversos , Proteína Relacionada ao Hormônio Paratireóideo/farmacologia , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia
9.
J Transl Med ; 15(1): 238, 2017 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-29178939

RESUMO

BACKGROUND AND AIMS: Intrahepatic cholangiocarcinoma (ICC) is an aggressive tumor with a high fatality rate. It was recently found that parathyroid hormone-like hormone (PTHLH) was frequently overexpressed in ICC compared with non-tumor tissue. This study aimed to elucidate the underlying mechanisms of PTHLH in ICC development. METHODS: The CCK-8 assay, colony formation assays, flow cytometry and a xenograft model were used to examine the role of PTHLH in ICC cells proliferation. Immunohistochemistry (IHC) and western blot assays were used to detect target proteins. Luciferase reporter, chromatin immunoprecipitation (ChIP) and DNA pull-down assays were used to verify the transcription regulation of activating transcription factor-2 (ATF2). RESULTS: PTHLH was significantly upregulated in ICC compared with adjacent and normal tissues. Upregulation of PTHLH indicated a poor pathological differentiation and intrahepatic metastasis. Functional study demonstrated that PTHLH silencing markedly suppressed ICC cells growth, while specific overexpression of PTHLH has the opposite effect. Mechanistically, secreted PTHLH could promote ICC cell growth by activating extracellular signal-related kinase (ERK) and c-Jun N-terminal kinase (JNK) signaling pathways, and subsequently upregulated ATF2 and cyclinD1 expression. Further study found that the promoter activity of PTHLH were negatively regulated by ATF2, indicating that a negative feedback loop exists. CONCLUSIONS: Our findings demonstrated that the ICC-secreted PTHLH plays a characteristic growth-promoting role through activating the canonical ERK/JNK-ATF2-cyclinD1 signaling pathways in ICC development. We identified a negative feedback loop formed by ATF2 and PTHLH. In this study, we explored the therapeutic implication for ICC patients.


Assuntos
Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/patologia , Proliferação de Células , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patologia , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Fator 2 Ativador da Transcrição/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Comunicação Autócrina/fisiologia , Neoplasias dos Ductos Biliares/genética , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Colangiocarcinoma/genética , Ciclina D1/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Síndromes Endócrinas Paraneoplásicas/genética , Síndromes Endócrinas Paraneoplásicas/metabolismo , Síndromes Endócrinas Paraneoplásicas/patologia , Proteína Relacionada ao Hormônio Paratireóideo/farmacologia , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Transdução de Sinais/efeitos dos fármacos
11.
Oncogene ; 36(31): 4498-4507, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28368420

RESUMO

Parathyroid hormone-related protein (PTHrP) is a critical regulator of bone resorption and augments osteolysis in skeletal malignancies. Here we report that the mature PTHrP1-36 hormone is processed by matrix metalloproteinases to yield a stable product, PTHrP1-17. PTHrP1-17 retains the ability to signal through PTH1R to induce calcium flux and ERK phosphorylation but not cyclic AMP production or CREB phosphorylation. Notably, PTHrP1-17 promotes osteoblast migration and mineralization in vitro, and systemic administration of PTHrP1-17 augments ectopic bone formation in vivo. Further, in contrast to PTHrP1-36, PTHrP1-17 does not affect osteoclast formation/function in vitro or in vivo. Finally, immunoprecipitation-mass spectrometry analyses using PTHrP1-17-specific antibodies establish that PTHrP1-17 is indeed generated by cancer cells. Thus, matrix metalloproteinase-directed processing of PTHrP disables the osteolytic functions of the mature hormone to promote osteogenesis, indicating important roles for this circuit in bone remodelling in normal and disease contexts.


Assuntos
Metaloproteinases da Matriz/fisiologia , Osteogênese , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Animais , Reabsorção Óssea/etiologia , Diferenciação Celular , Linhagem Celular , Movimento Celular , Feminino , Humanos , Camundongos , Osteoblastos/citologia , Osteoblastos/fisiologia
12.
Biochimie ; 138: 13-19, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28408247

RESUMO

Parathyroid hormone-related protein (PTHrP), a ubiquitously expressed protein, is composed of four functional domains including N-terminus, mid region, nuclear localization signal (NLS) and C-terminus. Under the direction of NLS, PTHrP can enter cell nucleus from cytoplasm and stimulate mitogenesis. Although PTHrP is considered to have important developmental roles, the role of PTHrP NLS and C-terminus in developmental process remains unknown, especially in T-cell development. Here, we used a knock-in mouse model, which expresses a truncated form of PTHrP missing the NLS (87-107) and C-terminus (108-139) of the protein, to examine the role of PTHrP NLS and C-terminus in T-cell development. Our results showed that the truncated PTHrP (1-84) led to abnormal subpopulations, impaired proliferation and increased apoptosis in the thymus, indicating that PTHrP is involved in the development of T cells, and the NLS and C-terminus part is necessary for the normal role of PTHrP in T-cell development.


Assuntos
Sequência de Aminoácidos , Sinais de Localização Nuclear , Proteína Relacionada ao Hormônio Paratireóideo/genética , Deleção de Sequência , Linfócitos T/metabolismo , Animais , Apoptose , Proliferação de Células , Camundongos , Modelos Animais , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Linfócitos T/fisiologia
13.
Physiol Rev ; 96(3): 831-71, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27142453

RESUMO

Although parathyroid hormone-related protein (PTHrP) was discovered as a cancer-derived hormone, it has been revealed as an important paracrine/autocrine regulator in many tissues, where its effects are context dependent. Thus its location and action in the vasculature explained decades-long observations that injection of PTH into animals rapidly lowered blood pressure by producing vasodilatation. Its roles have been specified in development and maturity in cartilage and bone as a crucial regulator of endochondral bone formation and bone remodeling, respectively. Although it shares actions with parathyroid hormone (PTH) through the use of their common receptor, PTHR1, PTHrP has other actions mediated by regions within the molecule beyond the amino-terminal sequence that resembles PTH, including the ability to promote placental transfer of calcium from mother to fetus. A striking feature of the physiology of PTHrP is that it possesses structural features that equip it to be transported in and out of the nucleus, and makes use of a specific nuclear import mechanism to do so. Evidence from mouse genetic experiments shows that PTHrP generated locally in bone is essential for normal bone remodeling. Whereas the main physiological function of PTH is the hormonal regulation of calcium metabolism, locally generated PTHrP is the important physiological mediator of bone remodeling postnatally. Thus the use of intermittent injection of PTH as an anabolic therapy for bone appears to be a pharmacological application of the physiological function of PTHrP. There is much current interest in the possibility of developing PTHrP analogs that might enhance the therapeutic anabolic effects.


Assuntos
Desenvolvimento Ósseo/fisiologia , Doenças Ósseas/tratamento farmacológico , Cartilagem/metabolismo , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Hormônio Paratireóideo/uso terapêutico , Animais , Cartilagem/crescimento & desenvolvimento , Humanos , Camundongos , Hormônio Paratireóideo/fisiologia
14.
Nat Commun ; 7: 11151, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-27039827

RESUMO

Precise coordination of cell growth, proliferation and differentiation is essential for the development of multicellular organisms. Here, we report that although the mechanistic target of rapamycin complex 1 (mTORC1) activity is required for chondrocyte growth and proliferation, its inactivation is essential for chondrocyte differentiation. Hyperactivation of mTORC1 via TSC1 gene deletion in chondrocytes causes uncoupling of the normal proliferation and differentiation programme within the growth plate, resulting in uncontrolled cell proliferation, and blockage of differentiation and chondrodysplasia in mice. Rapamycin promotes chondrocyte differentiation and restores these defects in mutant mice. Mechanistically, mTORC1 downstream kinase S6K1 interacts with and phosphorylates Gli2, and releases Gli2 from SuFu binding, resulting in nuclear translocation of Gli2 and transcription of parathyroid hormone-related peptide (PTHrP), a key regulator of bone development. Our findings demonstrate that dynamically controlled mTORC1 activity is crucial to coordinate chondrocyte proliferation and differentiation partially through regulating Gli2/PTHrP during endochondral bone development.


Assuntos
Condrócitos/citologia , Complexos Multiproteicos/fisiologia , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Serina-Treonina Quinases TOR/fisiologia , Animais , Diferenciação Celular , Crescimento Celular , Proliferação de Células , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Proteína Relacionada ao Hormônio Paratireóideo/genética , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Fosforilação , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Proteína 1 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/genética
15.
Ann Biol Clin (Paris) ; 74(1): 98-102, 2016.
Artigo em Francês | MEDLINE | ID: mdl-26878613

RESUMO

Hypercalcemia caused by tumor production of PTH-rp occurs most often in cases of squamous cell carcinoma of the lung, aerodigestive tract cancer, gynecological cancer and lymphoma. We report an exceptional case of PTH-rp related to a hepatic hemangioendothelioma. A 70 years-old male admitted for deterioration of the general state. The laboratory investigations revealed hypercalcemia, related to tumor production of PTH-rp. Imaging revealed tumoral hepatic lesions. Histopathological study and immunohistochemistry showed diffuse response for CD31 marker, CK20 (+) with CK7 (-) and hepatocyt antigen (-). The diagnosis of PTH-rp related to hepatic hemangioendothelioma was make. The patient died with recurrence of fatal hypercalcemia. Management of patients presenting with humoral hypercalcemia includes a vigorous search for tumor lesions. Elevated PTH-rp can be a bad prognostic factor. In front of tumoral liver lesions, a hepatic epithelioid hemangioendothelioma must be considered. Immunohistochemistry is necessary to make diagnosis.


Assuntos
Hemangioendotelioma Epitelioide/complicações , Hipercalcemia/etiologia , Neoplasias Hepáticas/complicações , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Idoso , Hemangioendotelioma Epitelioide/metabolismo , Hemangioendotelioma Epitelioide/patologia , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Síndromes Endócrinas Paraneoplásicas/etiologia , Síndromes Endócrinas Paraneoplásicas/patologia , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo
16.
Biomed Tech (Berl) ; 61(3): 253-66, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25781662

RESUMO

We set out to compare the osteogenicity of human mesenchymal stem (hMSCs) and osteoblasts (hOBs). Upon osteogenic induction in monolayer, hMSCs showed superior matrix mineralization expressing characteristic bone-related genes. For scaffold cultures, both cell types presented spindle-shaped, osteoblast-like morphologies forming a dense, interconnected network of high viability. On the scaffolds, hOBs proliferated faster. A general upregulation of parathyroid hormone-related protein (PTHrP), osteoprotegrin (OPG), receptor activator of NF-κB ligand (RANKL), sclerostin (SOST), and dentin matrix protein 1 (DMP1) was observed for both cell types. Simultaneously, PTHrP, RANKL and DMP-1 expression decreased under osteogenic stimulation, while OPG and SOST increased significantly. Following transplantation into NOD/SCID mice, µCT and histology showed increased bone deposition with hOBs. The bone was vascularized, and amounts further increased for both cell types after recombinant human bone morphogenic protein 7 (rhBMP-7) addition also stimulating osteoclastogenesis. Complete bone organogenesis was evidenced by the presence of osteocytes and hematopoietic precursors. Our study results support the asking to develop 3D cellular models closely mimicking the functions of living tissues suitable for in vivo translation.


Assuntos
Reabsorção Óssea/fisiopatologia , Células-Tronco Mesenquimais/citologia , Osteoblastos/citologia , Osteogênese/fisiologia , Proteína Relacionada ao Hormônio Paratireóideo/química , Animais , Reabsorção Óssea/metabolismo , Humanos , Camundongos , Camundongos SCID , Osteoblastos/química , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia
17.
Endocrinology ; 156(8): 2774-80, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26052897

RESUMO

The blood calcium concentration during fetal life is tightly regulated within a narrow range by highly interactive homeostatic mechanisms that include transport of calcium across the placenta and fluxes in and out of bone; the mechanisms of this regulation are poorly understood. Our findings that endochondral bone-specific PTH/PTHrP receptor (PPR) knockout (KO) mice showed significant reduction of fetal blood calcium concentration compared with that of control littermates at embryonic day 18.5 led us to focus on bone as a possibly major determinant of fetal calcium homeostasis. We found that the fetal calcium concentration of Runx2 KO mice was significantly higher than that of control littermates, suggesting that calcium flux into bone had a considerable influence on the circulating calcium concentration. Moreover, Runx2:PTH double mutant fetuses showed calcium levels similar to those of Runx2 KO mice, suggesting that part of the fetal hypocalcemia in PTH KO mice was caused by the increment of the mineralized bone mass allowed by the formation of osteoblasts. Finally, Rank:PTH double mutant mice had a blood calcium concentration even lower than that of the either Rank KO or PTH KO mice alone at embryonic day 18.5. These observations in our genetic models suggest that PTH/PTHrP receptor signaling in bones has a significant role of the regulation of fetal blood calcium concentration and that both placental transport and osteoclast activation contribute to PTH's hypercalcemic action. They also show that PTH-independent deposition of calcium in bone is the major controller of fetal blood calcium level.


Assuntos
Osso e Ossos/metabolismo , Cálcio/sangue , Sangue Fetal/metabolismo , Homeostase , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Hormônio Paratireóideo/fisiologia , Animais , Embrião de Mamíferos , Feminino , Homeostase/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hormônio Paratireóideo/genética , Proteína Relacionada ao Hormônio Paratireóideo/genética , Gravidez , Transdução de Sinais/fisiologia
18.
Arthritis Rheumatol ; 67(10): 2679-90, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26097038

RESUMO

OBJECTIVE: To determine whether and how the transcription factor Erg participates in the genesis, establishment, and maintenance of articular cartilage. METHODS: Floxed Erg mice were mated with Gdf5-Cre mice to generate conditional mutants lacking Erg in their joints. Joints of mutant and control mice were subjected to morphologic and molecular characterization and also to experimental surgically induced osteoarthritis (OA). Gene expression, promoter reporter assays, and gain- and loss-of-function in vitro tests were used to characterize molecular mechanisms of Erg action. RESULTS: Conditional Erg ablation did not elicit obvious changes in limb joint development and overall phenotype in juvenile mice. However, as mice aged, joints of mutant mice degenerated spontaneously and exhibited clear OA-like phenotypic defects. Joints in juvenile mutant mice were more sensitive to surgically induced OA and became defective sooner than operated joints in control mice. Global gene expression data and other studies identified parathyroid hormone-related protein (PTHrP) and lubricin as possible downstream effectors and mediators of Erg action in articular chondrocytes. Reporter assays using control and mutated promoter-enhancer constructs indicated that Erg acted on Ets DNA binding sites to stimulate PTHrP expression. Erg was up-regulated in severely affected areas in human OA articular cartilage but remained barely appreciable in areas of less affected cartilage. CONCLUSION: The study shows for the first time that Erg is a critical molecular regulator of the endurance of articular cartilage during postnatal life and that Erg can mitigate spontaneous and experimental OA. Erg appears to do this through regulating expression of PTHrP and lubricin, factors known for their protective roles in joints.


Assuntos
Cartilagem Articular/fisiopatologia , Proteínas Oncogênicas/fisiologia , Osteoartrite/fisiopatologia , Transativadores/fisiologia , Fatores de Transcrição/fisiologia , Animais , Cartilagem Articular/patologia , Células Cultivadas , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Camundongos Mutantes , Mutação/genética , Proteínas Oncogênicas/genética , Osteoartrite/patologia , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Fenótipo , Proteoglicanas/fisiologia , Fatores de Transcrição/genética , Regulador Transcricional ERG
19.
Arch Oral Biol ; 59(10): 1108-18, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25033382

RESUMO

OBJECTIVE: Jaw movement is an important mechanical factor for prenatal development of the condylar cartilage of mandible. Fetal jaw movement restriction has been shown to cause deformity of the mandibular condyle. We hypothesized that this treatment affects the expression of mechanosensitive molecules, namely Indian hedgehog (Ihh) and Parathyroid hormone related protein (PTHrP) in the condyle. EXPERIMENTAL METHODS: We restrained jaw movement by suturing the jaw of E15.5 mouse embryos and allowed them to develop until E18.5 using exo utero system, and analyzed them by immunohistochemistry and in situ hybridization methods. RESULTS: Morphological, histomorphometric and immunohistochemical study showed that the mandibular condylar cartilage was reduced and deformed, the volume and total cell numbers in the condylar cartilage were also reduced, and number and/or distribution of 5-bromo-2'-deoxyuridine-positive cells, Ihh-positive cells in the mesenchymal and pre-hypertrophic zones were significantly and correspondingly decreased in the sutured group. Using in situ hybridization, reduced expression of Ihh, PTHrP and their related receptors were observed in condylar cartilage of the sutured embryos. CONCLUSIONS: Our results revealed that the altered mechanical stress induced by prenatal jaw movement restriction decreased proliferating cells, the amount of cartilage, and altered expression of the Ihh and PTHrP, suggesting that Ihh act as mechanotransduction mediators in the development of mandibular condylar cartilage.


Assuntos
Cartilagem Articular/embriologia , Proteínas Hedgehog/metabolismo , Côndilo Mandibular/embriologia , Mecanotransdução Celular/fisiologia , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Animais , Feminino , Desenvolvimento Fetal , Proteínas Hedgehog/fisiologia , Imuno-Histoquímica , Hibridização In Situ , Camundongos , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Gravidez , Transdução de Sinais/fisiologia , Coloração e Rotulagem , Estresse Mecânico , Técnicas de Sutura
20.
Biochem Cell Biol ; 92(4): 305-15, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25051885

RESUMO

Parathyroid hormone-related peptide (PTHrP) is distributed in most fetal and adult tissues, and its expression correlates with the severity of colon carcinoma. Recently we obtained evidence that in Caco-2 cells, a cell line from human colorectal adenocarcinoma, exogenous PTHrP increases the number of live cells, via ERK1/2, p38 MAPK, and PI3-kinase and induces the expression of cyclin D1, a cell cycle regulatory protein. In this study, we further investigated the role of PTHrP in the regulation of the cell cycle progression in these intestinal cells. Flow cytometry analysis revealed that PTHrP treatment diminishes the number of cells in the G0/G1 phase and increases the number in both S and G2/M phases. The hormone increases the expression of CDK6 and diminishes the amount of negative cell cycle regulators p27Kip1, p15INK4B, and p53. However, PTHrP does not modify the expression of cyclin D3, CDK4, and p16INK4A. In addition, inhibitors of ERK1/2 (PD98059), p38 MAPK (SB203580), and PI3Kinase (LY294002) reversed PTHrP response in Caco-2 cells. Taken together, our results suggest that PTHrP positively modulates cell cycle progression and changes the expression of proteins involved in cell cycle regulation via ERK1/2, p38 MAPK, and PI3K signaling pathways in Caco-2 cells.


Assuntos
Sistema de Sinalização das MAP Quinases , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Células CACO-2 , Ciclina D3/genética , Ciclina D3/metabolismo , Quinase 4 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 6 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor de Quinase Dependente de Ciclina p15/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fase de Repouso do Ciclo Celular , Proteína Supressora de Tumor p53/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
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