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1.
Clin Dysmorphol ; 29(1): 46-48, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31205051
2.
J Med Genet ; 57(1): 18-22, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31413121

RESUMO

BACKGROUND: Metaphyseal dysplasia without hypotrichosis (MDWH) is a rare form of chondrodysplasia with no extraskeletal manifestations. MDWH is caused by RMRP mutations, but it is differentiated from the allelic condition cartilage-hair hypoplasia (CHH), which in addition to chondrodysplasia is characterised by thin hair, immunodeficiency and increased risk of malignancy. The long-term outcome of MDWH remains unknown. OBJECTIVE: We diagnosed severe agranulocytosis in a subject with RMRP mutations and normal hair. Based on this observation, we hypothesised that MDWH may, similar to CHH, associate with immune deficiency and malignancy. METHODS: We collected clinical and laboratory data for a cohort of 80 patients with RMRP mutations followed for over 30 years and analysed outcome data for those with features consistent with MDWH. RESULTS: In our cohort, we identified 10 patients with skeletal but no extraskeletal features during preschool age. Eight of these patients developed malignancy or clinically significant immunodeficiency during follow-up. Two of them died during chemotherapy for malignancy. At the time of the first extraskeletal manifestation, patients were school aged, 20, 43 and 50 years old. Laboratory signs of immunodeficiency (impaired lymphocyte proliferative responses) were demonstrated in four patients before the onset of symptoms. The patient outside this cohort, who had RMRP mutations, skeletal dysplasia, normal hair and severe agranulocytosis at 18 years of age, underwent haematopoietic stem cell transplantation. CONCLUSIONS: MDWH can present with severe late-onset extraskeletal manifestations and thus should be reclassified and managed as CHH.


Assuntos
Agranulocitose/etiologia , Síndromes de Imunodeficiência/etiologia , Mutação , Neoplasias/etiologia , Osteocondrodisplasias/patologia , RNA Longo não Codificante/genética , Adulto , Idoso , Feminino , Cabelo/anormalidades , Doença de Hirschsprung , Humanos , Pessoa de Meia-Idade , Osteocondrodisplasias/complicações , Osteocondrodisplasias/congênito , Osteocondrodisplasias/genética , Osteocondrodisplasias/metabolismo , Doenças da Imunodeficiência Primária , Adulto Jovem
3.
Nat Commun ; 10(1): 4457, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31575858

RESUMO

Mutations in genes encoding KATP channel subunits have been reported for pancreatic disorders and Cantú syndrome. Here, we report a syndrome in six patients from two families with a consistent phenotype of mild intellectual disability, similar facies, myopathy, and cerebral white matter hyperintensities, with cardiac systolic dysfunction present in the two oldest patients. Patients are homozygous for a splice-site mutation in ABCC9 (c.1320 + 1 G > A), which encodes the sulfonylurea receptor 2 (SUR2) subunit of KATP channels. This mutation results in an in-frame deletion of exon 8, which results in non-functional KATP channels in recombinant assays. SUR2 loss-of-function causes fatigability and cardiac dysfunction in mice, and reduced activity, cardiac dysfunction and ventricular enlargement in zebrafish. We term this channelopathy resulting from loss-of-function of SUR2-containing KATP channels ABCC9-related Intellectual disability Myopathy Syndrome (AIMS). The phenotype differs from Cantú syndrome, which is caused by gain-of-function ABCC9 mutations, reflecting the opposing consequences of KATP loss- versus gain-of-function.


Assuntos
Trifosfato de Adenosina/metabolismo , Canalopatias/metabolismo , Predisposição Genética para Doença/genética , Deficiência Intelectual/metabolismo , Doenças Musculares/metabolismo , Mutação , Receptores Sulfonilureia/genética , Receptores Sulfonilureia/metabolismo , Adolescente , Adulto , Sequência de Aminoácidos , Animais , Cardiomegalia/genética , Cardiomegalia/metabolismo , Linhagem Celular , Criança , Modelos Animais de Doenças , Facies , Feminino , Doenças Genéticas Ligadas ao Cromossomo X/genética , Coração , Cardiopatias/genética , Cardiopatias/metabolismo , Homozigoto , Humanos , Hipertricose/genética , Hipertricose/metabolismo , Deficiência Intelectual/parasitologia , Masculino , Complexo Mediador/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Doenças Musculares/genética , Transtornos do Neurodesenvolvimento/genética , Transtornos do Neurodesenvolvimento/metabolismo , Transtornos do Neurodesenvolvimento/fisiopatologia , Osteocondrodisplasias/genética , Osteocondrodisplasias/metabolismo , Linhagem , Fenótipo , Rubídio , Sequenciamento Completo do Genoma , Adulto Jovem , Peixe-Zebra
4.
Genesis ; 57(11-12): e23336, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31520578

RESUMO

Acrodysostosis is an extremely rare disorder at birth, that is, characterized by skeletal dysplasia with short stature and midfacial hypoplasia, which has been reported to be caused by PDE4D and PRKAR1A gene mutations. Here, a Chinese boy with acrodysostosis, ventricular septal defect, and pulmonary hypertension was recruited for our study, and his clinical and biochemical characteristics were analyzed. A novel de novo heterozygous missense mutation (NM_001104631: c.2030A>C, p.Tyr677Ser) of the PDE4D gene was detected by whole exome sequencing and confirmed by Sanger sequencing. The c.2030A>C (p.Tyr677Ser) variant was located in exon 15 of the PDE4D gene, predicted to be damaging by a functional prediction program and shown to be highly conserved among many species. Further functional analysis showed that the p.Tyr677Ser substitution changes the function of the PDE4D protein, affects its subcellular localization in transfected cells, increases PDE4 activity in the regulation of cAMP signaling and affects cell proliferation. Our study identified a novel de novo PDE4D mutation in acrodysostosis of Chinese origin that not only contributes a deeper appreciation of the phenotypic characteristics of patients with PDE4D mutations but also expands the spectrum of PDE4D mutations.


Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Disostoses/genética , Deficiência Intelectual/genética , Osteocondrodisplasias/genética , Grupo com Ancestrais do Continente Asiático/genética , Pré-Escolar , China , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Disostoses/metabolismo , Células HEK293 , Células HeLa , Heterozigoto , Humanos , Deficiência Intelectual/metabolismo , Masculino , Mutação , Mutação de Sentido Incorreto/genética , Osteocondrodisplasias/metabolismo , Sequenciamento Completo do Exoma
5.
Ecotoxicol Environ Saf ; 183: 109575, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31442808

RESUMO

Tibial Dyschondroplasia (TD), a metabolic disease of fast growing poultry birds that effects the growth of bone and cartilage, is characterized by anorexia, mental depression and lameness. Wnt/ß-catenin pathway can mediate the occurrence of TD, and previous study showed the therapeutic effect of TanshinoneⅡA to TD Broilers. However there is no report about the effect of TanshinoneⅡA treating TD broiler chicken through wnt/ß-catenin pathway. The objective of this study was to explore the potential mechanism of how Tanshinone II A treats TD. Hematoxylin and eosin staining was used to study histologic pathology of growth plates. Key gene expressions were tested by western blot and reverse transcription quantitative real-time PCR. Results compared with control groups, showed the TD broilers' growth plate performed significantly better by treating with TanshinoneⅡA. After chickens treated by TanshinoneⅡA, the gene and protein expression of WNT5α and BMP-2 were increased (P < 0.05), but the ß-catenin were decreased (P < 0.05), which are all key genes expressed in wnt/ß-catenin pathway. Therefore, TanshinoneⅡA can potentially treat TD by affecting the expression of genes in wnt/ß-catenin pathway and it has availability to use as treatment for TD broilers.


Assuntos
Abietanos/uso terapêutico , Lâmina de Crescimento/efeitos dos fármacos , Osteocondrodisplasias/veterinária , Doenças das Aves Domésticas/tratamento farmacológico , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/metabolismo , Abietanos/farmacologia , Animais , Galinhas , Lâmina de Crescimento/patologia , Osteocondrodisplasias/induzido quimicamente , Osteocondrodisplasias/tratamento farmacológico , Osteocondrodisplasias/metabolismo , Doenças das Aves Domésticas/induzido quimicamente , Doenças das Aves Domésticas/metabolismo , Tiram/toxicidade , Tíbia
6.
Int J Mol Sci ; 20(16)2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31408960

RESUMO

Autophagy (particularly macroautophagy) is a bulk degradation process used by eukaryotic cells in order to maintain adequate energy levels and cellular homeostasis through the delivery of long-lived proteins and organelles to the lysosome, resulting in their degradation. It is becoming increasingly clear that many of the molecular requirements to fulfil autophagy intersect with those of conventional and unconventional membrane trafficking pathways. Of particular interest is the dependence of these processes on multiple members of the Rab family of small GTP binding proteins. Rab33b is a protein that localises to the Golgi apparatus and has suggested functions in both membrane trafficking and autophagic processes. Interestingly, mutations in the RAB33B gene have been reported to cause the severe skeletal disorder, Smith-McCort Dysplasia; however, the molecular basis for Rab33b in this disorder remains to be determined. In this review, we focus on the current knowledge of the participation of Rab33b and its interacting partners in membrane trafficking and macroautophagy, and speculate on how its function, and dysfunction, may contribute to human disease.


Assuntos
Autofagia , Mapas de Interação de Proteínas , Proteínas rab de Ligação ao GTP/metabolismo , Animais , Transporte Biológico , Retículo Endoplasmático/metabolismo , Endossomos/metabolismo , Complexo de Golgi/metabolismo , Humanos , Lisossomos/metabolismo , Osteocondrodisplasias/metabolismo
7.
PLoS Genet ; 15(7): e1008215, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31260448

RESUMO

The unfolded protein response (UPR) is a conserved cellular response to the accumulation of proteinaceous material in endoplasmic reticulum (ER), active both in health and disease to alleviate cellular stress and improve protein folding. Multiple epiphyseal dysplasia (EDM5) is a genetic skeletal condition and a classic example of an intracellular protein aggregation disease, whereby mutant matrilin-3 forms large insoluble aggregates in the ER lumen, resulting in a specific 'disease signature' of increased expression of chaperones and foldases, and alternative splicing of the UPR effector XBP1. Matrilin-3 is expressed exclusively by chondrocytes thereby making EDM5 a perfect model system to study the role of protein aggregation in disease. In order to dissect the role of XBP1 signalling in aggregation-related conditions we crossed a p.V194D Matn3 knock-in mouse model of EDM5 with a mouse line carrying a cartilage specific deletion of XBP1 and analysed the resulting phenotype. Interestingly, the growth of mice carrying the Matn3 p.V194D mutation compounded with the cartilage specific deletion of XBP1 was severely retarded. Further phenotyping revealed increased intracellular retention of amyloid-like aggregates of mutant matrilin-3 coupled with dramatically decreased cell proliferation and increased apoptosis, suggesting a role of XBP1 signalling in protein accumulation and/or degradation. Transcriptomic analysis of chondrocytes extracted from wild type, EDM5, Xbp1-null and compound mutant lines revealed that the alternative splicing of Xbp1 is crucial in modulating levels of protein aggregation. Moreover, through detailed transcriptomic comparison with a model of metaphyseal chondrodysplasia type Schmid (MCDS), an UPR-related skeletal condition in which XBP1 was removed without overt consequences, we show for the first time that the differentiation-state of cells within the cartilage growth plate influences the UPR resulting from retention of a misfolded mutant protein and postulate that modulation of XBP1 signalling pathway presents a therapeutic target for aggregation related conditions in cells undergoing proliferation.


Assuntos
Mutação , Osteocondrodisplasias/genética , Osteocondrodisplasias/patologia , Proteína 1 de Ligação a X-Box/genética , Processamento Alternativo , Animais , Apoptose , Proliferação de Células , Células Cultivadas , Condrócitos/citologia , Condrócitos/metabolismo , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático , Perfilação da Expressão Gênica , Humanos , Proteínas Matrilinas/química , Proteínas Matrilinas/genética , Camundongos , Osteocondrodisplasias/metabolismo , Agregados Proteicos , Transdução de Sinais , Resposta a Proteínas não Dobradas , Proteína 1 de Ligação a X-Box/metabolismo
8.
Int J Exp Pathol ; 100(1): 4-11, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30912609

RESUMO

This review, based on the BSMB Fell-Muir Lecture I presented in July 2018 at the Matrix Biology Europe Conference in Manchester, gives a personal perspective of my own laboratory's contributions to research into type X collagen, metaphyseal chondrodysplasia type Schmid and potential treatments for this disorder that are currently entering clinical trial. I have tried to set the advances made in the context of the scientific technologies available at the time and how these have changed over the more than three decades of this research.


Assuntos
Pesquisa Biomédica/métodos , Ensaios Clínicos como Assunto/métodos , Clonagem Molecular/métodos , Colágeno Tipo X/genética , Terapia Genética/métodos , Mutação , Osteocondrodisplasias/terapia , Animais , Pesquisa Biomédica/história , Ensaios Clínicos como Assunto/história , Colágeno Tipo X/metabolismo , Congressos como Assunto , Difusão de Inovações , Predisposição Genética para Doença , Terapia Genética/história , História do Século XX , História do Século XXI , Humanos , Osteocondrodisplasias/genética , Osteocondrodisplasias/história , Osteocondrodisplasias/metabolismo , Fenótipo
9.
Birth Defects Res ; 111(5): 237-247, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30719872

RESUMO

BACKGROUND: The mutant chondrodysplasia (cho) is a cartilage-targeting disorder in C57BL mice that results in dwarfing and other malformations stemming from this collagenopathy. Clarke Fraser made the discovery of the mutation accidentally in the early 1960s during the thalidomide tragedy. METHODS: For this review we identified key research on cho as since its discovery. Relevant data were compiled to make a comprehensive review that details discoveries associated with the cho mutation, that describes the associated phenotypes and molecular mechanisms, and that provides a discussion surrounding its current clinical relevance. RESULTS: Mechanistically, cho acts by hindering chondrogenesis and endochondral bone formation. The phenotype results from a 1-nt deletion in the gene encoding the alpha 1 chain of type XI collagen. For more than half a century, researchers have studied the pathogenesis of the cho mutation in relation to a variety of mouse models of human birth defects and disease. These studies have resulted in several discoveries linking cho with such human disorders as dwarfism, tracheal stenosis, cleft palate, pulmonary hypoplasia, and osteoarthritis (OA). CONCLUSION: The study of cho has led to numerous advances in understanding human birth defects, congenital disorders, and adult human disease. The most recent studies have suggested a role for the TGF-Beta, HtrA1, Ddr2, and Mmp-13 pathway in the degradation of articular cartilage and the development of OA in cho/+ mice. We have shown that the anti-hypertension drug Losartan is a TGF-Beta blocker that could be used to treat OA in Stickler syndrome, and thereby rescue the WT phenotype.


Assuntos
Osteocondrodisplasias/genética , Osteocondrodisplasias/metabolismo , Osteocondrodisplasias/fisiopatologia , Anormalidades Múltiplas/metabolismo , Animais , Cartilagem Articular , Colágeno Tipo XI/genética , Colágeno Tipo XI/metabolismo , Modelos Animais de Doenças , Pulmão/anormalidades , Pulmão/metabolismo , Pneumopatias/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Anormalidades Musculoesqueléticas/metabolismo , Mutação , Osteoartrite , Fenótipo
10.
Front Horm Res ; 51: 147-159, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30641531

RESUMO

Pseudohypoparathyroidism (PHP), pseudo-PHP, acrodysostosis, and progressive osseous heteroplasia are heterogeneous disorders characterized by physical findings, differently associated in each subtype, including short bones, short stature, a stocky build, ectopic ossifications (features associated with Albright's hereditary osteodystrophy), as well as laboratory abnormalities consistent with hormone resistance, such as hypocalcemia, hyperphosphatemia, and elevated parathyroid hormone (PTH) and thyroid-stimulating hormone levels. All these disorders are caused by impairments in the cAMP-mediated signal transduction pathway and, in particular, in the PTH/PTHrP signaling pathway: the main subtypes of PHP and related disorders are caused by de novo or autosomal dominantly inherited inactivating genetic mutations, and/or epigenetic, sporadic, or genetic-based alterations within or upstream of GNAS, PRKAR1A, PDE4D, and PDE3A. Here we will review the impressive progress that has been made over the past 30 years on the pathophysiology of these diseases and will describe the recently proposed novel nomenclature and classification. The new term "inactivating PTH/PTHrP signaling disorder," iPPSD: (1) defines the common mechanism responsible for all diseases, (2) does not require a confirmed genetic defect, (3) avoids ambiguous terms like "pseudo," and (4) eliminates the clinical or molecular overlap between diseases.


Assuntos
Doenças Ósseas Metabólicas , Disostoses , Deficiência Intelectual , Ossificação Heterotópica , Osteocondrodisplasias , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Hormônio Paratireóideo/metabolismo , Pseudo-Hipoparatireoidismo , Transdução de Sinais/fisiologia , Dermatopatias Genéticas , Doenças Ósseas Metabólicas/classificação , Doenças Ósseas Metabólicas/diagnóstico , Doenças Ósseas Metabólicas/metabolismo , Doenças Ósseas Metabólicas/terapia , Disostoses/classificação , Disostoses/diagnóstico , Disostoses/metabolismo , Disostoses/terapia , Humanos , Deficiência Intelectual/classificação , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/metabolismo , Deficiência Intelectual/terapia , Ossificação Heterotópica/classificação , Ossificação Heterotópica/diagnóstico , Ossificação Heterotópica/metabolismo , Ossificação Heterotópica/terapia , Osteocondrodisplasias/classificação , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/metabolismo , Osteocondrodisplasias/terapia , Pseudo-Hipoparatireoidismo/classificação , Pseudo-Hipoparatireoidismo/diagnóstico , Pseudo-Hipoparatireoidismo/metabolismo , Pseudo-Hipoparatireoidismo/terapia , Dermatopatias Genéticas/classificação , Dermatopatias Genéticas/diagnóstico , Dermatopatias Genéticas/metabolismo , Dermatopatias Genéticas/terapia
11.
EBioMedicine ; 40: 695-709, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30685387

RESUMO

BACKGROUND: Mutations in the SLC26A2 gene cause a spectrum of currently incurable human chondrodysplasias. However, genotype-phenotype relationships of SLC26A2-deficient chondrodysplasias are still perplexing and thus stunt therapeutic development. METHODS: To investigate the causative role of SLC26A2 deficiency in chondrodysplasias and confirm its skeleton-specific pathology, we generated and analyzed slc26a2-/- and Col2a1-Cre; slc26a2fl/fl mice. The therapeutic effect of NVP-BGJ398, an FGFR inhibitor, was tested with both explant cultures and timed pregnant females. FINDINGS: Two lethal forms of human SLC26A2-related chondrodysplasias, achondrogenesis type IB (ACG1B) and atelosteogenesis type II (AO2), are phenocopied by slc26a2-/- mice. Unexpectedly, slc26a2-/- chondrocytes are defective for collagen secretion, exhibiting intracellular retention and compromised extracellular deposition of ColII and ColIX. As a consequence, the ATF6 arm of the unfolded protein response (UPR) is preferentially triggered to overactivate FGFR3 signaling by inducing excessive FGFR3 in slc26a2-/- chondrocytes. Consistently, suppressing FGFR3 signaling by blocking either FGFR3 or phosphorylation of the downstream effector favors the recovery of slc26a2-/- cartilage cultures from impaired growth and unbalanced cell proliferation and apoptosis. Moreover, administration of an FGFR inhibitor to pregnant females shows therapeutic effects on pathological features in slc26a2-/- newborns. Finally, we confirm the skeleton-specific lethality and pathology of global SLC26A2 deletion through analyzing the Col2a1-Cre; slc26a2fl/fl mouse line. INTERPRETATION: Our study unveils a previously unrecognized pathogenic mechanism underlying ACG1B and AO2, and supports suppression of FGFR3 signaling as a promising therapeutic approach for SLC26A2-related chondrodysplasias. FUND: This work was supported by National Natural Science Foundation of China (81871743, 81730065 and 81772377).


Assuntos
Acondroplasia/genética , Acondroplasia/metabolismo , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais , Transportadores de Sulfato/deficiência , Resposta a Proteínas não Dobradas , Acondroplasia/patologia , Fator 6 Ativador da Transcrição/genética , Fator 6 Ativador da Transcrição/metabolismo , Animais , Cartilagem/metabolismo , Cartilagem/patologia , Diferenciação Celular/genética , Condrócitos/citologia , Condrócitos/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Regulação da Expressão Gênica no Desenvolvimento , Lâmina de Crescimento/embriologia , Lâmina de Crescimento/patologia , Humanos , Camundongos , Camundongos Knockout , Morfogênese/genética , Mutação , Osteocondrodisplasias/genética , Osteocondrodisplasias/metabolismo , Osteocondrodisplasias/patologia , Fenótipo , Resposta a Proteínas não Dobradas/genética
12.
Cell Stress Chaperones ; 24(1): 159-173, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30543055

RESUMO

Mesencephalic astrocyte-derived neurotrophic factor (MANF) is an endoplasmic reticulum (ER) resident protein that can be secreted due to an imperfect KDEL motif. MANF plays a cytoprotective role in several soft tissues and is upregulated in conditions resulting from intracellular retention of mutant protein, including two skeletal diseases, metaphyseal chondrodysplasia, Schmid type (MCDS) and multiple epiphyseal dysplasia (MED). The role of MANF in skeletal tissue homeostasis is currently unknown. Interestingly, cartilage-specific deletion of Manf in a mouse model of MED resulted in increased disease severity, suggesting its upregulation may be chondroprotective. Treatment of MED chondrocytes with exogenous MANF led to a decrease in the cellular levels of BiP (GRP78), confirming MANF's potential to modulate ER stress responses. However, it did not alleviate the intracellular retention of mutant matrilin-3, suggesting that it is the intracellular MANF that is of importance in the pathobiology of skeletal dysplasias. The Col2Cre-driven deletion of Manf from mouse cartilage resulted in a chondrodysplasia-like phenotype. Interestingly, ablation of MANF in cartilage did not have extracellular consequences but led to an upregulation of several ER-resident chaperones including BiP. This apparent induction of ER stress in turn led to dysregulated chondrocyte apoptosis and decreased proliferation, resulting in reduced long bone growth. We have previously shown that ER stress is an underlying disease mechanism for several skeletal dysplasias. The cartilage-specific deletion of Manf described in this study phenocopies our previously published chondrodysplasia models, further confirming that ER stress itself is sufficient to disrupt skeletal growth and thus represents a potential therapeutic target.


Assuntos
Condrócitos/metabolismo , Retículo Endoplasmático/metabolismo , Homeostase , Fatores de Crescimento Neural/metabolismo , Animais , Apoptose/efeitos dos fármacos , Cartilagem/efeitos dos fármacos , Cartilagem/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Condrócitos/efeitos dos fármacos , Condrócitos/patologia , Perda do Embrião/patologia , Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Deleção de Genes , Lâmina de Crescimento/efeitos dos fármacos , Lâmina de Crescimento/metabolismo , Homeostase/efeitos dos fármacos , Pulmão/anormalidades , Pulmão/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Especificidade de Órgãos/efeitos dos fármacos , Osteocondrodisplasias/diagnóstico por imagem , Osteocondrodisplasias/metabolismo , Osteocondrodisplasias/patologia , Osteogênese/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Respiração , Tunicamicina/farmacologia , Resposta a Proteínas não Dobradas/efeitos dos fármacos
13.
Bone ; 120: 354-363, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30448303

RESUMO

LBR (Lamin B Receptor) encodes a bifunctional protein important for cholesterol biosynthesis and heterochromatin organization on the inner nuclear membrane. Pathogenic variants in LBR are associated with marked phenotypic variability, ranging from the benign Pelger-Huët anomaly to lethal Greenberg Dysplasia. We performed trio exome sequencing (ES) on two patients with atypical variants of skeletal dysplasia and their unaffected parents. Patient 1 exhibited frontal bossing, mid-face hypoplasia, short stature with rhizomelic limb shortening, and relative macrocephaly at birth. Although remained short, Patient 1 later showed spontaneous improvement in her skeletal findings. Exome sequencing revealed two novel variants in LBR, c.1504C > G (p.Arg502Gly) in exon 12 and c.1748G > T (p.Arg583Leu) in exon 14, which were inherited from her unaffected father and mother, respectively. Sterol analysis revealed an increased level of cholesta­8,14­dien­3ß­ol to 2.9% of total sterols, consistent with a functional deficiency of 3ß­hydroxysterol Δ14­reductase. Patient 2 presented at birth with short stature and marked rhizomelic limb shortening but later exhibited decreasing severity of shortening of the long bones and improvement in the radiographic skeletal abnormalities although he continued to be significantly short at age 10 years. Exome sequencing revealed that Patient 2 is homozygous for a pathogenic variant c.1534C > T (p.Arg512Trp) in exon 12 of LBR, which was inherited from his unaffected consanguineous parents. This report provides further evidence for a phenotypic spectrum of LBR-associated disorders and expands the genotypic spectrum by describing 3 novel disease-causing variants that have not been previously associated with a disease. Moreover, our data on Patient 1 demonstrate that variants throughout the gene appear to influence both the sterol reductase and nuclear functions of LBR.


Assuntos
Osteocondrodisplasias/metabolismo , Osteocondrodisplasias/patologia , Receptores Citoplasmáticos e Nucleares/genética , Adulto , Sequência de Bases , Criança , Pré-Escolar , Evolução Molecular , Feminino , Variação Genética , Humanos , Lactente , Recém-Nascido , Linfócitos/metabolismo , Masculino , Osteocondrodisplasias/diagnóstico por imagem , Linhagem , Fenótipo
14.
Curr Mol Med ; 18(7): 448-458, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30539698

RESUMO

BACKGROUND: Transforming growth factor-ß (TGF-ß)/nodal signaling is involved in early embryonic patterning in vertebrates. Nodal modulator (Nomo, also called pM5) is a negative regulator of nodal signaling. Currently, the role of nomo gene in cartilage development in vertebrates remains unknown. METHODS: Nomo mutants were generated in a knockout model of zebrafish by clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (CRISPR/Cas9) targeting of the fibronectin type III domain. The expression of related genes, which are critical for chondrogenesis, was analyzed by whole-mount in situ hybridization and qRT-PCR. Whole-mount alcian staining was performed to analyze the cartilage structure. RESULTS: nomo is highly expressed in various tissues including the cartilage. We successfully constructed a zebrafish nomo knockout model. nomo homozygous mutants exhibited varying degrees of hypoplasia and dysmorphism on 4 and 5 dpf, which is similar to chondrodysplasia in humans. The key genes of cartilage and skeletal development, including sox9a, sox9b, dlx1a, dlx2a, osx, col10a1, and col11a2 were all downregulated in nomo mutants compared with the wildtype. CONCLUSION: The nomo gene positively regulates the expression of the master regulator and other key development genes involved in bone formation and cartilage development and it is essential for cartilage development in zebrafish.


Assuntos
Animais Geneticamente Modificados , Cartilagem , Condrogênese/genética , Proteínas de Membrana/deficiência , Osteocondrodisplasias , Proteínas de Peixe-Zebra/deficiência , Peixe-Zebra , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/metabolismo , Cartilagem/metabolismo , Cartilagem/patologia , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Humanos , Osteocondrodisplasias/genética , Osteocondrodisplasias/metabolismo , Osteocondrodisplasias/patologia , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
15.
Osteoarthritis Cartilage ; 26(11): 1551-1561, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30086379

RESUMO

OBJECTIVE: FGFR3 chondrodysplasia is caused by a gain-of-function mutation of the FGFR3 gene. The disease causes abnormal growth plate cartilage and lacks effective drug treatment. We sought to establish an in vivo model for the study of FGFR3 chondrodysplasia pathology and drug testing. DESIGN: We created cartilage from human induced pluripotent stem cells (hiPSCs) and transplanted the cartilage into the subcutaneous spaces of immunodeficient mice. We then created cartilage from the hiPSCs of patients with FGFR3 chondrodysplasia and transplanted them into immunodeficient mice. We treated some mice with a FGFR inhibitor after the transplantation. RESULTS: Xenografting the hiPSC-derived cartilage reproduced human growth plate cartilage consisting of zones of resting, proliferating, prehypertrophic and hypertrophic chondrocytes and bone in immunodeficient mice. Immunohistochemistry of xenografts using anti-human nuclear antigen antibody indicated that all chondrocytes in growth plate cartilage were human, whereas bone was composed of human and mouse cells. The pathology of small hypertrophic chondrocytes due to up-regulated FGFR3 signaling in FGFR3 skeletal dysplasia was recapitulated in growth plate cartilage formed in the xenografts of patient-specific hiPSC-derived cartilage. The mean diameters of hypertrophic chondrocytes between wild type and thanatophoric dysplasia were significantly different (95% CI: 13.2-26.9; n = 4 mice, one-way analysis of variance (ANOVA)). The pathology was corrected by systemic administration of a FGFR inhibitor to the mice. CONCLUSION: The patient-specific growth plate cartilage xenograft model for FGFR3 skeletal dysplasia indicated recapitulation of pathology and effectiveness of a FGFR inhibitor for treatment and warrants more study for its usefulness to study disease pathology and drug testing.


Assuntos
Cartilagem/patologia , Lâmina de Crescimento/patologia , Mutação , Osteocondrodisplasias/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Animais , Cartilagem/metabolismo , Ciclo Celular , Diferenciação Celular , Proliferação de Células , Modelos Animais de Doenças , Lâmina de Crescimento/metabolismo , Xenoenxertos , Camundongos , Osteocondrodisplasias/metabolismo , Osteocondrodisplasias/patologia , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais
16.
Biochem Biophys Res Commun ; 506(2): 307-314, 2018 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-30139519

RESUMO

Actin cytoskeleton dynamics depend on a tight regulation of actin filament formation from an intracellular pool of monomers, followed by their linkage to each other or to cell membranes, followed by their depolymerization into a fresh pool of actin monomers. The ubiquitous requirement for continuous actin remodeling that is necessary for many cellular functions is orchestrated in large part by actin binding proteins whose affinity for actin is altered by inositol phospholipids, most prominently PI(4,5)P2 (phosphatidylinositol 4,5-bisphosphate). The kinetics of PI(4,5)P2 synthesis and hydrolysis, its lateral distribution within the lipid bilayer, and coincident detection of PI(4,5)P2 and another signal, all play a role in determining when and where a particular PI(4,5)P2-regulated protein is inactivated or activated to exert its effect on the actin cytoskeleton. This review summarizes a range of models that have been developed to explain how PI(4,5)P2 might function in the complex chemical and structural environment of the cell based on a combination of experiment and computational studies.


Assuntos
Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Proteínas dos Microfilamentos/metabolismo , Miosinas/metabolismo , Fosfatidilinositol 4,5-Difosfato/metabolismo , Fosfolipase C beta/metabolismo , Citoesqueleto de Actina/genética , Citoesqueleto de Actina/ultraestrutura , Actinas/química , Actinas/genética , Animais , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Células Eucarióticas/citologia , Células Eucarióticas/metabolismo , Células Eucarióticas/ultraestrutura , Regulação da Expressão Gênica , Humanos , Cinética , Proteínas dos Microfilamentos/genética , Modelos Biológicos , Miosinas/genética , Osteocondrodisplasias/genética , Osteocondrodisplasias/metabolismo , Osteocondrodisplasias/patologia , Fosfolipase C beta/genética , Transdução de Sinais , Talina/genética , Talina/metabolismo , Xenopus laevis
17.
Environ Sci Pollut Res Int ; 25(28): 28264-28274, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30076550

RESUMO

Tetramethyl thiuram disulfide (thiram) is one of the important pesticides, which is extensively used in agriculture, but if it is combined with the cell membrane, then it causes membrane damage, bone morphogenic inactivation, and inhibited angiogenesis. Thiram has been considered a common cause of tibial dyschondrolplasia (TD) in various avian species, because it becomes the part of feed due to environmental contamination and its overuse in agriculture as pesticides or fungicide. However, there is no systematic study on the changes of the correlation indexes with toxic effect of the thiram in chickens. Therefore, we evaluated the toxic effects of thiram on growth performance of chickens, viscera organ index, pathological changes in tissue, and gene expression associated with osteoblast differentiation, vascularization, and tibial bone development. For this study, 1-day chickens (n = 300) were randomly distributed into two equal groups, control group (normal basal diet) and thiram group (adding thiram 40 mg/kg in basal diet). The result presented that thiram group chickens were looking unhealthy, lazy, and showing clinical symptoms like lameness. Thiram treatment significantly reduced the performance of chickens, liver index, and tibial length compared with control group. The toxic effect of thiram increased the visceral organ index (spleen and cardiac), tibia index, and TD severity considerably. It also increased serum Ca2+ and P3+ concentration and decreased tibial density compared to control chickens but the difference was not significant. Histopathology of tibia and liver showed that there were severe lesions due to toxic effect of thiram. Furthermore, HIF-1α and VEGF antibody localizations were increased and WNT4 localization was reduced significantly in immunohistochemical analysis. This systemic study of toxic effects of thiram in chicken concluded that thiram reduced the growth performance of chickens through decreasing liver index, whereas increasing kidney, cardiac, and spleen index, and induced TD by changing the expressions of VEGF, HIF-1α, and WNT4.


Assuntos
Osteocondrodisplasias/induzido quimicamente , Praguicidas/toxicidade , Doenças das Aves Domésticas/induzido quimicamente , Tiram/toxicidade , Animais , Galinhas , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Neovascularização Patológica/induzido quimicamente , Osteocondrodisplasias/metabolismo , Osteocondrodisplasias/patologia , Osteocondrodisplasias/veterinária , Doenças das Aves Domésticas/metabolismo , Doenças das Aves Domésticas/patologia , Tíbia/efeitos dos fármacos , Tíbia/metabolismo , Tíbia/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteína Wnt4/metabolismo
18.
Clin Genet ; 94(5): 429-437, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30051459

RESUMO

Spondylometaphyseal dysplasia (SMD) is characterized by developmental changes in long bones and vertebrae. It has large phenotypic diversity and multiple genetic causes, including a recent link to novel variants in the extracellular matrix (ECM) protein fibronectin (FN), a regulator of ECM assembly and key link between the ECM and proper cell function. We identified a patient with a unique SMD, similar to SMD with corner fractures. The patient has been followed over 19 years and presents with short stature, genu varum, kyphoscoliosis, and pectus carinatum. Radiography shows metaphyseal changes that resolved over time, vertebral changes, and capitular avascular necrosis. Whole exome sequencing identified a novel heterozygous FN1 variant (p.Cys97Trp). Using mass spectroscopy, mutant FN was detected in plasma and in culture medium of primary dermal fibroblasts isolated from the patient, but mutant protein was much less abundant than wild-type FN. Immunofluorescence and immunoblotting analyses show that mutant fibroblasts assemble significantly lower amounts of FN matrix than wild-type cells, and mutant FN was preferentially retained within the endoplasmic reticulum. This work highlights the importance of FN in skeletal development, and its potential role in the pathogenesis of a subtype of SMD.


Assuntos
Fibronectinas/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Variação Genética , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/genética , Alelos , Criança , Pré-Escolar , Proteínas da Matriz Extracelular , Fibroblastos/metabolismo , Fibronectinas/sangue , Fibronectinas/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Mutação , Osteocondrodisplasias/metabolismo , Osteocondrodisplasias/fisiopatologia , Radiografia , Sequenciamento Completo do Exoma
19.
J Biol Chem ; 293(24): 9162-9175, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29735531

RESUMO

Chondrocyte hypertrophy is the terminal step in chondrocyte differentiation and is crucial for endochondral bone formation. How signaling pathways regulate chondrocyte hypertrophic differentiation remains incompletely understood. In this study, using a Tbx18:Cre (Tbx18Cre/+) gene-deletion approach, we selectively deleted the gene for the signaling protein SMAD family member 4 (Smad4f/f ) in the limbs of mice. We found that the Smad4-deficient mice develop a prominent shortened limb, with decreased expression of chondrocyte differentiation markers, including Col2a1 and Acan, in the humerus at mid-to-late gestation. The most striking defects in these mice were the absence of stylopod elements and failure of chondrocyte hypertrophy in the humerus. Moreover, expression levels of the chondrocyte hypertrophy-related markers Col10a1 and Panx3 were significantly decreased. Of note, we also observed that the expression of runt-related transcription factor 2 (Runx2), a critical mediator of chondrocyte hypertrophy, was also down-regulated in Smad4-deficient limbs. To determine how the skeletal defects arose in the mouse mutants, we performed RNA-Seq with ChIP-Seq analyses and found that Smad4 directly binds to regulatory elements in the Runx2 promoter. Our results suggest a new mechanism whereby Smad4 controls chondrocyte hypertrophy by up-regulating Runx2 expression during skeletal development. The regulatory mechanism involving Smad4-mediated Runx2 activation uncovered here provides critical insights into bone development and pathogenesis of chondrodysplasia.


Assuntos
Desenvolvimento Ósseo , Condrócitos/patologia , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento , Proteína Smad4/genética , Animais , Diferenciação Celular , Proliferação de Células , Condrócitos/citologia , Condrócitos/metabolismo , Condrogênese , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Hipertrofia/genética , Hipertrofia/metabolismo , Hipertrofia/patologia , Camundongos , Osteocondrodisplasias/genética , Osteocondrodisplasias/metabolismo , Osteocondrodisplasias/patologia , Proteína Smad4/metabolismo
20.
Biomed Res Int ; 2018: 6796271, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29750168

RESUMO

Tibial dyschondroplasia (TD) is a disease of rapid growing chickens that occurs in many avian species; it is characterized by nonvascular and nonmineralized growth plates, along with tibia bone deformation and lameness. Icariin is widely used to treat bone diseases in humans, but no report is available regarding the effectiveness of icariin against avian TD. Therefore, this study was designed to determine its effect against TD. For this purpose, a total of 180 broiler chicks were distributed into three groups including control, TD, and icariin group. Control group was given a standard normal diet, while TD and icariin groups received normal standard diet containing 50 mg/kg thiram to induce TD from days 3 to 7 after hatch. After the induction of TD, the chicks of icariin group were fed with standard normal diet by adding 10 mg/kg icariin in water. Then morphological and production parameters analysis of tibial bone indicators, physiological index changes, and gene expression were examined. The results showed that icariin administration not only decreased the mortality but also mitigated the lameness and promoted the angiogenesis, which diminished the TD lesion and significantly increased the expression of P2RX7 (P < 0.05) in TD affected thiram induced chicks. In conclusion, present findings suggest that icariin has a significant role in promoting the recovery of chicken growth plates affected by TD via regulating the P2RX7. Our findings reveal a new target for clinical treatment and prevention of TD in broiler chickens.


Assuntos
Flavonoides/farmacologia , Osteocondrodisplasias/tratamento farmacológico , Doenças das Aves Domésticas/tratamento farmacológico , Tíbia/efeitos dos fármacos , Animais , Galinhas , Expressão Gênica/efeitos dos fármacos , Lâmina de Crescimento/efeitos dos fármacos , Lâmina de Crescimento/metabolismo , Incidência , Masculino , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Osteocondrodisplasias/metabolismo , Doenças das Aves Domésticas/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Tiram/farmacologia , Tíbia/metabolismo
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