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1.
Biochem Soc Trans ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38940746

RESUMEN

Cellular senescence, a form of terminal cell cycle arrest, is as a key driver of organismal ageing and an important factor in age-related diseases. Insights into the senescent phenotype have led to the development of novel therapeutic strategies, collectively known as senotherapies, that aim to ameliorate the detrimental effects of senescent cell accumulation in tissues. The senotherapeutic field has rapidly evolved over the past decade, with clinical translation of the first drugs discovered currently underway. What began as the straightforward removal of senescent cells using repurposed compounds, which were given the name of senolytics, has grown into an expanding field that uses different state of the art approaches to achieve the goal of preventing the build-up of senescent cells in the body. Here, we summarize the emergence of a new generation of senotherapies, based on improving the efficacy and safety of the original senolytics by making them targeted, but also branching out into drugs that prevent senescence (senoblockers) or revert it (senoreversers).The use of nanotechnology, specific antibodies, cell-based approaches and restored immunosurveillance is likely to revolutionize the field of senotherapies in the near future, hopefully allowing it to realize its full clinical potential.

2.
Artículo en Inglés | MEDLINE | ID: mdl-34590512

RESUMEN

An innovative approach to patient management, evidence-based policy development, and clinical drug trials is required to provide personalized care and to improve the likelihood of finding an effective treatment for Motor Neurone Disease (MND). The MiNDAus Partnership builds on and extends existing national collaborations in a targeted approach to improve the standard and coordination of care for people living with MND in Australia, and to enhance the prospects of discovering a cure or treatment. Relationships have been developed between leading clinical and research groups as well as patient-centered organizations, care providers, and philanthropy with a shared vision. MiNDAus has established a corporate structure and meets at least biannually to decide on how best to progress research, drug development, and patient management. The key themes are; (i) empowering patients and their family carers to engage in self-management and ensure personalized service provision, treatment, and policy development, (ii) integration of data collection so as to better inform policy development, (iii) unifying patients and carers with advocacy groups, funding bodies, clinicians and academic institutions so as to inform policy development and research, (iv) coordination of research efforts and development of standardized national infrastructure for conducting innovative clinical MND trials that can be harmonized within Australia and with international trials consortia. Such a collaborative approach is required across stakeholders in order to develop innovative management guidelines, underpinned by necessary and evidence-based policy change recommendations, which, will ensure the best patient care until a cure is discovered.


Asunto(s)
Esclerosis Amiotrófica Lateral , Enfermedad de la Neurona Motora , Australia , Cuidadores , Recolección de Datos , Humanos , Enfermedad de la Neurona Motora/terapia
3.
J Bone Miner Res ; 37(3): 531-546, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34841579

RESUMEN

Neurogenic heterotopic ossifications (NHOs) form in periarticular muscles after severe spinal cord (SCI) and traumatic brain injuries. The pathogenesis of NHO is poorly understood with no effective preventive treatment. The only curative treatment remains surgical resection of pathological NHOs. In a mouse model of SCI-induced NHO that involves a transection of the spinal cord combined with a muscle injury, a differential gene expression analysis revealed that genes involved in inflammation such as interleukin-1ß (IL-1ß) were overexpressed in muscles developing NHO. Using mice knocked-out for the gene encoding IL-1 receptor (IL1R1) and neutralizing antibodies for IL-1α and IL-1ß, we show that IL-1 signaling contributes to NHO development after SCI in mice. Interestingly, other proteins involved in inflammation that were also overexpressed in muscles developing NHO, such as colony-stimulating factor-1, tumor necrosis factor, or C-C chemokine ligand-2, did not promote NHO development. Finally, using NHO biopsies from SCI and TBI patients, we show that IL-1ß is expressed by CD68+ macrophages. IL-1α and IL-1ß produced by activated human monocytes promote calcium mineralization and RUNX2 expression in fibro-adipogenic progenitors isolated from muscles surrounding NHOs. Altogether, these data suggest that interleukin-1 promotes NHO development in both humans and mice. © 2021 American Society for Bone and Mineral Research (ASBMR).


Asunto(s)
Interleucina-1beta/metabolismo , Osificación Heterotópica , Traumatismos de la Médula Espinal , Animales , Humanos , Inflamación/complicaciones , Interleucina-1 , Ratones , Músculos/patología , Osificación Heterotópica/patología , Médula Espinal/metabolismo , Médula Espinal/patología , Traumatismos de la Médula Espinal/complicaciones
4.
JBMR Plus ; 2(3): 154-163, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-30283900

RESUMEN

Kyphosis and scoliosis are common spinal disorders that occur as part of complex syndromes or as nonsyndromic, idiopathic diseases. Familial and twin studies implicate genetic involvement, although the causative genes for idiopathic kyphoscoliosis remain to be identified. To facilitate these studies, we investigated progeny of mice treated with the chemical mutagen N-ethyl-N-nitrosourea (ENU) and assessed them for morphological and radiographic abnormalities. This identified a mouse with kyphoscoliosis due to fused lumbar vertebrae, which was inherited as an autosomal dominant trait; the phenotype was designated as hereditary vertebral fusion (HVF) and the locus as Hvf. Micro-computed tomography (µCT) analysis confirmed the occurrence of nonsyndromic kyphoscoliosis due to fusion of lumbar vertebrae in HVF mice, consistent with a pattern of blocked vertebrae due to failure of segmentation. µCT scans also showed the lumbar vertebral column of HVF mice to have generalized disc narrowing, displacement with compression of the neural spine, and distorted transverse processes. Histology of lumbar vertebrae revealed HVF mice to have irregularly shaped vertebral bodies and displacement of intervertebral discs and ossification centers. Genetic mapping using a panel of single nucleotide polymorphic (SNP) loci arranged in chromosome sets and DNA samples from 23 HVF (eight males and 15 females) mice, localized Hvf to chromosome 4A3 and within a 5-megabase (Mb) region containing nine protein coding genes, two processed transcripts, three microRNAs, five small nuclear RNAs, three large intergenic noncoding RNAs, and 24 pseudogenes. However, genome sequence analysis in this interval did not identify any abnormalities in the coding exons, or exon-intron boundaries of any of these genes. Thus, our studies have established a mouse model for a monogenic form of nonsyndromic kyphoscoliosis due to fusion of lumbar vertebrae, and further identification of the underlying genetic defect will help elucidate the molecular mechanisms involved in kyphoscoliosis. © 2018 The Authors. JBMR Plus is published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.

5.
Arthritis Rheumatol ; 70(2): 255-265, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29108111

RESUMEN

OBJECTIVE: Endoplasmic reticulum aminopeptidase 1 (ERAP-1) and ERAP-2, encoded on chromosome 5q15, trim endogenous peptides for HLA-mediated presentation to the immune system. Polymorphisms in ERAP1 and/or ERAP2 are strongly associated with several immune-mediated diseases with specific HLA backgrounds, implicating altered peptide handling and presentation as prerequisites for autoreactivity against an arthritogenic peptide. Given the thorough characterization of disease risk-associated polymorphisms that alter ERAP activity, this study aimed instead to interrogate the expression effect of chromosome 5q15 polymorphisms to determine their effect on ERAP isoform and protein expression. METHODS: RNA sequencing and genotyping across chromosome 5q15 were performed to detect genetic variants in ERAP1 and ERAP2 associated with altered total gene and isoform-specific expression. The functional implication of a putative messenger RNA splice-altering variant on ERAP-1 protein levels was validated using mass spectrometry. RESULTS: Polymorphisms associated with ankylosing spondylitis (AS) significantly influenced the transcript and protein expression of ERAP-1 and ERAP-2. Disease risk-associated polymorphisms in and around both genes were also associated with increased gene expression. Furthermore, key risk-associated ERAP1 variants were associated with altered transcript splicing, leading to allele-dependent alternate expression of 2 distinct isoforms and significant differences in the type of ERAP-1 protein produced. CONCLUSION: In accordance with studies demonstrating that polymorphisms that increase aminopeptidase activity predispose to immune disease, the increased risk also attributed to increased expression of ERAP1 and ERAP2 supports the notion of using aminopeptidase inhibition to treat AS and other ERAP-associated conditions.


Asunto(s)
Aminopeptidasas/genética , Enfermedades del Sistema Inmune/genética , Antígenos de Histocompatibilidad Menor/genética , Espondilitis Anquilosante/genética , Adulto , Aminopeptidasas/metabolismo , Cromosomas Humanos Par 5/genética , Femenino , Expresión Génica , Predisposición Genética a la Enfermedad , Variación Genética , Genotipo , Humanos , Masculino , Espectrometría de Masas/métodos , Persona de Mediana Edad , Antígenos de Histocompatibilidad Menor/metabolismo , Polimorfismo Genético , Análisis de Secuencia de ARN/métodos , Adulto Joven
6.
Motriz (Online) ; 24(2): e1018166, 2018.
Artículo en Inglés | LILACS | ID: biblio-895061

RESUMEN

AIMS: In recent years, recognition of the pedagogical nature of coaching has gained increasing traction. However, within this line of inquiry, only limited attention has been given to the work of Lev Vygotsky. The aim of this article is to construct a more comprehensive case about how Vygotsky's principal ideas can aid our understanding of both the act and process of sports coaching. METHODS: The method involves constructing a case from Vygotsky's original work, and how it has been interpreted by others, related to the applicability of using some of his concepts to further our understanding of sports coaching practice. The case presented represents an interpretive and considered approach to the question and task at hand. DISCUSSION: The discussion is centred on the utility of Vygotsky's theorising to sports coaching practice. In particular his advocacy of (1) the cultural-historical perspective; (2) the claim of language as the greatest mediator in learning; (3) how perezhivane contributes to such knowledge generation; (4) the zone of proximal development and the role of the 'more capable other' within it; and (5) the dialectical approach, focussing on the dynamic relationship between everyday and scientific concepts, are given primacy. CONCLUSION: Finally, a reflective conclusion summarises the main points made and suggests possible future courses of action.(AU)


Asunto(s)
Humanos , Negociación , Educación y Entrenamiento Físico , Deportes/educación
7.
BMC Musculoskelet Disord ; 18(1): 228, 2017 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-28558827

RESUMEN

BACKGROUND: Ankylosing spondylitis (AS) is characterised by immune-mediated arthritis and osteoproliferation, ultimately leading to joint ankylosis. Whether inflammation is necessary for osteoproliferation is controversial, fuelled by the unclear efficacy of anti-inflammatory treatments on radiographic progression. In proteoglycan-induced spondylitis (PGISp), a mouse model of AS, inflammation is the prerequisite for osteoproliferation as osteoproliferation was only observed following inflammation-driven intervertebral disc (IVD) destruction. We hypothesised that early intervention with a potent anti-inflammatory therapy would protect IVD integrity and consequently alter disease progression. METHODS: PGISp mice received vehicle or a combination of etanercept (ETN) plus prednisolone (PRD) therapy for 2 or 6 weeks initiated at an early disease stage. Peripheral arthritis was scored longitudinally. Spinal disease was assessed using a semi-quantitative histological scoring regimen including inflammation, joint destruction and excessive tissue formation. RESULTS: ETN + PRD therapy significantly delayed the onset of peripheral arthritis. IVD integrity was significantly protected when treatment was commenced in early disease. Six-weeks of treatment resulted in trends towards reductions in intervertebral joint damage and excessive tissue formation. IVD score distribution was dichotomized, likely reflecting the extent of axial disease at initiation of therapy. In the sub-group of mice with high IVD destruction scores, ETN + PRD treatment significantly reduced IVD destruction severity, inflammation and bone erosion and reduced cartilage damage and excessive tissue formation. CONCLUSIONS: Early intervention with anti-inflammatory treatment not only improved inflammatory symptoms but also ameliorated structural damage of spine in PGISp mice. This preclinical observation suggests that early anti-inflammatory intervention may slow radiographic progression in AS patients.


Asunto(s)
Antiinflamatorios/administración & dosificación , Modelos Animales de Enfermedad , Proteoglicanos/toxicidad , Espondilitis Anquilosante/inducido químicamente , Espondilitis Anquilosante/tratamiento farmacológico , Animales , Esquema de Medicación , Quimioterapia Combinada , Etanercept/administración & dosificación , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Prednisolona/administración & dosificación , Espondilitis Anquilosante/patología
8.
Ann Rheum Dis ; 76(1): 261-269, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27125523

RESUMEN

OBJECTIVES: Ankylosing spondylitis (AS) is a highly heritable immune-mediated arthropathy. Inflammation in AS is poorly understood. TBX21 encodes T-bet, a transcription factor, lying within a locus with genome-wide significant association with AS. T-bet is implicated in innate and adaptive immunity. However, the role of T-bet in AS pathogenesis is unclear. METHODS: We assessed the importance of T-bet in disease development and progression in peripheral blood mononuclear cells from 172 AS cases and 83 healthy controls carrying either risk or protective alleles of the peak AS-associated TBX21 single nucleotide polymorphism. Kinetics and localisation of T-bet expression in the SKG mouse model of spondyloarthropathy was examined, along with the impact of Tbx21 knockout on arthritis development in SKG mice. RESULTS: Patients with AS had higher T-bet expression than healthy individuals, driven predominantly by natural killer and CD8+ T cells, with expression levels in CD8+ T cells completely distinguishing AS cases from healthy controls. T-bet expression was increased in AS cases carrying risk compared with protective alleles of rs11657479. In curdlan-treated SKG mice, T-bet expression increased early after disease initiation and persisted throughout the course of disease. There was marked reduction in gut and peripheral joint inflammation, and less IFNγ-producing and IL-17-producing CD8+ T cells, in Tbx21-/- compared with wild-type SKG mice. CONCLUSIONS: AS-associated variants in TBX21 influence T-bet expression. T-bet+ innate and adaptive immune cells have altered IL-17 and IFNγ, and early activation marker CD69 expression than T-bet cells. This indicates that T-bet is a major component of inflammatory pathways of spondyloarthropathy in humans and mice.


Asunto(s)
Artritis Experimental/genética , Citocinas/biosíntesis , Espondilitis Anquilosante/genética , Proteínas de Dominio T Box/genética , Adulto , Anciano , Animales , Artritis Experimental/inmunología , Artritis Experimental/patología , Linfocitos T CD8-positivos/inmunología , Estudios de Casos y Controles , Femenino , Regulación de la Expresión Génica/fisiología , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Mediadores de Inflamación/metabolismo , Células Asesinas Naturales/inmunología , Ganglios Linfáticos/inmunología , Masculino , Ratones Endogámicos BALB C , Ratones Noqueados , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Espondilitis Anquilosante/inmunología , Espondilitis Anquilosante/patología , Proteínas de Dominio T Box/biosíntesis , Adulto Joven
9.
PLoS One ; 11(12): e0167916, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27959934

RESUMEN

Non-syndromic kyphosis is a common disorder that is associated with significant morbidity and has a strong genetic involvement; however, the causative genes remain to be identified, as such studies are hampered by genetic heterogeneity, small families and various modes of inheritance. To overcome these limitations, we investigated 12 week old progeny of mice treated with the chemical mutagen N-ethyl-N-nitrosourea (ENU) using phenotypic assessments including dysmorphology, radiography, and dual-energy X-ray absorptiometry. This identified a mouse with autosomal recessive kyphosis (KYLB). KYLB mice, when compared to unaffected littermates, had: thoraco-lumbar kyphosis, larger vertebrae, and increased body length and increased bone area. In addition, female KYLB mice had increases in bone mineral content and plasma alkaline phosphatase activity. Recombination mapping localized the Kylb locus to a 5.5Mb region on chromosome 15A1, which contained 51 genes, including the natriuretic peptide receptor 3 (Npr3) gene. DNA sequence analysis of Npr3 identified a missense mutation, Tyr209Asn, which introduced an N-linked glycosylation consensus sequence. Expression of wild-type NPR3 and the KYLB-associated Tyr209Asn NPR3 mutant in COS-7 cells demonstrated the mutant to be associated with abnormal N-linked glycosylation and retention in the endoplasmic reticulum that resulted in its absence from the plasma membrane. NPR3 is a decoy receptor for C-type natriuretic peptide (CNP), which also binds to NPR2 and stimulates mitogen-activated protein kinase (MAPK) signaling, thereby increasing the number and size of hypertrophic chondrocytes. Histomorphometric analysis of KYLB vertebrae and tibiae showed delayed endochondral ossification and expansion of the hypertrophic zones of the growth plates, and immunohistochemistry revealed increased p38 MAPK phosphorylation throughout the growth plates of KYLB vertebrae. Thus, we established a model of kyphosis due to a novel NPR3 mutation, in which loss of plasma membrane NPR3 expression results in increased MAPK pathway activation, causing elongation of the vertebrae and resulting in kyphosis.


Asunto(s)
Cifosis/genética , Sistema de Señalización de MAP Quinasas , Mutación Missense , Receptores del Factor Natriurético Atrial/genética , Animales , Densidad Ósea , Células COS , Chlorocebus aethiops , Modelos Animales de Enfermedad , Etilnitrosourea/toxicidad , Femenino , Glicosilación , Cifosis/metabolismo , Cifosis/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Procesamiento Proteico-Postraduccional , Columna Vertebral/diagnóstico por imagen , Columna Vertebral/metabolismo , Tibia/diagnóstico por imagen , Tibia/metabolismo
10.
EBioMedicine ; 11: 101-117, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27568222

RESUMEN

RORα is a member of the nuclear receptor (NR) superfamily and analysis of the (global) RORα-deficient mouse model revealed this NR has a role in glycemic control and fat deposition. Therefore, we generated an adipose-specific RORα 'gain of function' mouse model under the control of the fatty acid binding protein 4 (FABP4) promoter to elucidate the function of RORα in adipose tissue. The Tg-FABP4-RORα4 mice demonstrated a shift in fat distribution to non-adipose tissues when challenged with a high fat diet (HFD). Specifically, we observed a subcutaneous lipodystrophy, accompanied by hepatomegaly (fatty liver/mild portal fibrosis) and splenomegaly; in a background of decreased weight gain and total body fat after HFD. Moreover, we observed significantly higher fasting blood glucose and impaired clearance of glucose in Tg-FABP4-RORα4 mice. Genome wide expression and qPCR profiling analysis identified: (i) subcutaneous adipose specific decreases in the expression of genes involved in fatty acid biosynthesis, lipid droplet expansion and glycemic control, and (ii) the fibrosis pathway as the most significant pathway [including dysregulation of the collagen/extracellular matrix (ECM) pathways] in subcutaneous adipose and liver. The pathology presented in the Tg-FABP4-RORα4 mice is reminiscent of human metabolic disease (associated with aberrant ECM expression) highlighting the therapeutic potential of this NR.


Asunto(s)
Tejido Adiposo/metabolismo , Adiposidad/genética , Glucemia , Expresión Génica , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Tejido Adiposo/inmunología , Tejido Adiposo/patología , Adiposidad/inmunología , Animales , Biomarcadores , Análisis por Conglomerados , Matriz Extracelular/metabolismo , Fibrosis , Perfilación de la Expresión Génica , Genotipo , Prueba de Tolerancia a la Glucosa , Hepatomegalia/genética , Hepatomegalia/metabolismo , Hepatomegalia/patología , Humanos , Resistencia a la Insulina , Metabolismo de los Lípidos , Lípidos/sangre , Hígado/metabolismo , Hígado/patología , Ratones , Ratones Transgénicos , Especificidad de Órganos , Fenotipo , Esplenomegalia/genética , Esplenomegalia/metabolismo , Esplenomegalia/patología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Transgenes , Aumento de Peso
11.
Arthritis Res Ther ; 18: 35, 2016 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-26831337

RESUMEN

BACKGROUND: Ankylosing spondylitis (AS) is an immune-mediated arthritis particularly targeting the spine and pelvis and is characterised by inflammation, osteoproliferation and frequently ankylosis. Current treatments that predominately target inflammatory pathways have disappointing efficacy in slowing disease progression. Thus, a better understanding of the causal association and pathological progression from inflammation to bone formation, particularly whether inflammation directly initiates osteoproliferation, is required. METHODS: The proteoglycan-induced spondylitis (PGISp) mouse model of AS was used to histopathologically map the progressive axial disease events, assess molecular changes during disease progression and define disease progression using unbiased clustering of semi-quantitative histology. PGISp mice were followed over a 24-week time course. Spinal disease was assessed using a novel semi-quantitative histological scoring system that independently evaluated the breadth of pathological features associated with PGISp axial disease, including inflammation, joint destruction and excessive tissue formation (osteoproliferation). Matrix components were identified using immunohistochemistry. RESULTS: Disease initiated with inflammation at the periphery of the intervertebral disc (IVD) adjacent to the longitudinal ligament, reminiscent of enthesitis, and was associated with upregulated tumor necrosis factor and metalloproteinases. After a lag phase, established inflammation was temporospatially associated with destruction of IVDs, cartilage and bone. At later time points, advanced disease was characterised by substantially reduced inflammation, excessive tissue formation and ectopic chondrocyte expansion. These distinct features differentiated affected mice into early, intermediate and advanced disease stages. Excessive tissue formation was observed in vertebral joints only if the IVD was destroyed as a consequence of the early inflammation. Ectopic excessive tissue was predominantly chondroidal with chondrocyte-like cells embedded within collagen type II- and X-rich matrix. This corresponded with upregulation of mRNA for cartilage markers Col2a1, sox9 and Comp. Osteophytes, though infrequent, were more prevalent in later disease. CONCLUSIONS: The inflammation-driven IVD destruction was shown to be a prerequisite for axial disease progression to osteoproliferation in the PGISp mouse. Osteoproliferation led to vertebral body deformity and fusion but was never seen concurrent with persistent inflammation, suggesting a sequential process. The findings support that early intervention with anti-inflammatory therapies will be needed to limit destructive processes and consequently prevent progression of AS.


Asunto(s)
Modelos Animales de Enfermedad , Progresión de la Enfermedad , Osteogénesis/fisiología , Espondilitis Anquilosante/etiología , Espondilitis Anquilosante/patología , Animales , Femenino , Inflamación/complicaciones , Inflamación/patología , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados
12.
BMC Musculoskelet Disord ; 16: 368, 2015 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-26612313

RESUMEN

BACKGROUND: No treatment to date is available which specifically targets bone formation in ankylosing spondylitis (AS). Several recent studies have shown that sclerostin (SOST), a Wnt inhibitor specific to osteocytes and chondrocytes, is down-regulated in AS patients. This suggests Wnt signalling may be upregulated, and application of exogenous recombinant SOST (rSOST) may inhibit Wnt signalling and slow pathological bone formation. METHODS: The proteoglycan-induced spondylitis (PGISp) mouse model in which we have previously demonstrated downregulated SOST expression, was used for this study. Mice were injected with 2.5 ug rSOST/day for a period of 8 weeks following induction of disease. Axial skeleton disease development was assessed by histology and skeletal changes examined using DEXA. RESULTS: rSOST treatment had no effect on peripheral or axial disease development, bone density or disease severity. Injected rSOST was stable over 8 h and residual levels were evident 24 h after injection, resulting in a cumulative increase in SOST serum levels over the treatment time course. Immunohistochemical examination of SOST levels within the joints in non-rSOST treated PGISp mice showed a significant decrease in the percentage of positive osteocytes in the unaffected joints compared to the affected joints, while no difference was seen in rSOST treated mice. This suggests that rSOST treatment increases the number of SOST-positive osteocytes in unaffected joints but not affected joints, despite having no impact on the number of joints affected by disease. CONCLUSIONS: Although not disease-modifying, rSOST treatment did appear to regulate SOST levels in the joints suggesting biological activity. Further dose response studies are required and SOST may require modifications to improve its bone targeting ability in order to affect tissue formation to a meaningful level in this model.


Asunto(s)
Proteínas Morfogenéticas Óseas/administración & dosificación , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Espondilitis Anquilosante/tratamiento farmacológico , Espondilitis Anquilosante/patología , Proteínas Adaptadoras Transductoras de Señales , Animales , Femenino , Marcadores Genéticos , Células HEK293 , Humanos , Inyecciones Subcutáneas , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Resultado del Tratamiento
13.
Ann Rheum Dis ; 74(11): 2092-5, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26088389

RESUMEN

INTRODUCTION: Single nucleotide polymorphisms in ERAP2 are strongly associated with ankylosing spondylitis (AS). One AS-associated single nucleotide polymorphism, rs2248374, causes a truncated ERAP2 protein that is degraded by nonsense-mediated decay. Approximately 25% of the populations of European ancestry are therefore natural ERAP2 knockouts. We investigated the effect of this associated variant on HLA class I allele presentation, surface heavy chains, endoplasmic reticulum (ER) stress markers and cytokine gene transcription in AS. METHODS: Patients with AS and healthy controls with either AA or GG homozygous status for rs2248374 were studied. Antibodies to CD14, CD19-ECD, HLA-A-B-C, Valpha7.2, CD161, anti-HC10 and anti-HLA-B27 were used to analyse peripheral blood mononuclear cells. Expression levels of ER stress markers (GRP78 and CHOP) and proinflammatory genes (tumour necrosis factor (TNF), IL6, IL17 and IL22) were assessed by qPCR. RESULTS: There was no significant difference in HLA-class I allele presentation or major histocompatibility class I heavy chains or ER stress markers GRP78 and CHOP or proinflammatory gene expression between genotypes for rs2248374 either between cases, between cases and controls, and between controls. DISCUSSION: Large differences were not seen in HLA-B27 expression or cytokine levels between subjects with and without ERAP2 in AS cases and controls. This suggests that ERAP2 is more likely to influence AS risk through other mechanisms.


Asunto(s)
Aminopeptidasas/genética , Citocinas/genética , Estrés del Retículo Endoplásmico/genética , Antígeno HLA-B27/genética , Leucocitos Mononucleares/inmunología , ARN Mensajero/metabolismo , Espondilitis Anquilosante/genética , Aminopeptidasas/inmunología , Estudios de Casos y Controles , Citocinas/inmunología , Chaperón BiP del Retículo Endoplásmico , Estrés del Retículo Endoplásmico/inmunología , Expresión Génica , Antígeno HLA-B27/inmunología , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/inmunología , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas Pesadas de Inmunoglobulina/inmunología , Interleucina-17/genética , Interleucina-17/inmunología , Interleucina-6/genética , Interleucina-6/inmunología , Interleucinas/genética , Interleucinas/inmunología , Reacción en Cadena de la Polimerasa , Polimorfismo de Nucleótido Simple , Receptores de Antígenos de Linfocitos B/genética , Receptores de Antígenos de Linfocitos B/inmunología , Espondilitis Anquilosante/inmunología , Factor de Transcripción CHOP/genética , Factor de Transcripción CHOP/inmunología , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología , Interleucina-22
14.
J Invest Dermatol ; 135(10): 2446-2454, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25938557

RESUMEN

Recent studies have reported that epigenetic mechanisms may regulate the initiation and progress of squamous differentiation in normal and transformed keratinocytes. In particular, the role of the repressive H3K27me3 mark in the regulation of squamous differentiation has been prominent. However, there is conflicting literature showing that squamous differentiation may be dependent upon or independent of changes in H3K27me3 status. In this study we have examined the binding of trimethylated H3K27 to the promoters of proliferation or differentiation genes in keratinocytes undergoing squamous differentiation in vitro and in vivo. Initially, we examined the expression levels for EZH1, EZH2, and H3K27me3 in differentiating keratinocytes in vitro and in vivo. We extended this to include H3K27me3 chromatin immunoprecipitation sequencing (ChIP-seq). Based on these studies, we could find no evidence for an association between widespread gain or loss of H3K27me3 on the promoters of proliferation-specific or differentiation-specific target genes, respectively, during squamous differentiation in adult human keratinocytes. These data suggest that squamous differentiation may occur independent of regulation by H3K27me3 on proliferation and differentiation genes of normal adult human keratinocytes.


Asunto(s)
Diferenciación Celular/genética , Transformación Celular Neoplásica/genética , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Complejo Represivo Polycomb 2/genética , Regiones Promotoras Genéticas , Adulto , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Células Cultivadas , Inmunoprecipitación de Cromatina , Metilación de ADN , Proteína Potenciadora del Homólogo Zeste 2 , Humanos , Queratinocitos/citología , Queratinocitos/fisiología , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados , Muestreo , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología
15.
PLoS One ; 10(4): e0122650, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25860694

RESUMEN

Ectopic calcification (EC), which is the pathological deposition of calcium and phosphate in extra-skeletal tissues, may be associated with hypercalcaemic and hyperphosphataemic disorders, or it may occur in the absence of metabolic abnormalities. In addition, EC may be inherited as part of several monogenic disorders and studies of these have provided valuable insights into the metabolic pathways regulating mineral metabolism. For example, studies of tumoural calcinosis, a disorder characterised by hyperphosphataemia and progressive EC, have revealed mutations of fibroblast growth factor 23 (FGF23), polypeptide N-acetyl galactosaminyltransferase 3 (GALNT3) and klotho (KL), which are all part of a phosphate-regulating pathway. However, such studies in humans are limited by the lack of available large families with EC, and to facilitate such studies we assessed the progeny of mice treated with the chemical mutagen N-ethyl-N-nitrosourea (ENU) for EC. This identified two mutants with autosomal recessive forms of EC, and reduced lifespan, designated Ecalc1 and Ecalc2. Genetic mapping localized the Ecalc1 and Ecalc2 loci to a 11.0 Mb region on chromosome 5 that contained the klotho gene (Kl), and DNA sequence analysis identified nonsense (Gln203Stop) and missense (Ile604Asn) Kl mutations in Ecalc1 and Ecalc2 mice, respectively. The Gln203Stop mutation, located in KL1 domain, was severely hypomorphic and led to a 17-fold reduction of renal Kl expression. The Ile604Asn mutation, located in KL2 domain, was predicted to impair klotho protein stability and in vitro expression studies in COS-7 cells revealed endoplasmic reticulum retention of the Ile604Asn mutant. Further phenotype studies undertaken in Ecalc1 (kl203X/203X) mice demonstrated elevations in plasma concentrations of phosphate, FGF23 and 1,25-dihydroxyvitamin D. Thus, two allelic variants of Kl that develop EC and represent mouse models for tumoural calcinosis have been established.


Asunto(s)
Calcinosis/patología , Etilnitrosourea/toxicidad , Glucuronidasa/genética , Alelos , Secuencia de Aminoácidos , Animales , Células COS , Calcinosis/metabolismo , Chlorocebus aethiops , Codón sin Sentido , Modelos Animales de Enfermedad , Retículo Endoplásmico/metabolismo , Factor-23 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos/sangre , Factores de Crecimiento de Fibroblastos/genética , Sitios Genéticos , Genotipo , Glucuronidasa/química , Glucuronidasa/metabolismo , Humanos , Riñón/metabolismo , Proteínas Klotho , Longevidad/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Mutación Missense , N-Acetilgalactosaminiltransferasas/genética , Fenotipo , Fosfatos/sangre , Polimorfismo de Nucleótido Simple , Alineación de Secuencia , Vitamina D/análogos & derivados , Vitamina D/sangre , Polipéptido N-Acetilgalactosaminiltransferasa
16.
Nat Methods ; 12(4): 339-42, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25751143

RESUMEN

We compared quantitative RT-PCR (qRT-PCR), RNA-seq and capture sequencing (CaptureSeq) in terms of their ability to assemble and quantify long noncoding RNAs and novel coding exons across 20 human tissues. CaptureSeq was superior for the detection and quantification of genes with low expression, showed little technical variation and accurately measured differential expression. This approach expands and refines previous annotations and simultaneously generates an expression atlas.


Asunto(s)
Perfilación de la Expresión Génica , ARN Largo no Codificante/genética , ARN/genética , Análisis de Secuencia/métodos , Humanos , Células K562 , Reacción en Cadena de la Polimerasa , ARN/sangre , ARN/química
17.
Am J Physiol Endocrinol Metab ; 308(2): E159-71, 2015 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-25424999

RESUMEN

The Rar-related orphan receptor-α (Rorα) is a nuclear receptor that regulates adiposity and is a potential regulator of energy homeostasis. We have demonstrated that the Rorα-deficient staggerer (sg/sg) mice display a lean and obesity-resistant phenotype. Adaptive Ucp1-dependent thermogenesis in beige/brite and brown adipose tissue serves as a mechanism to increase energy expenditure and resist obesity. DEXA and MRI analysis demonstrated significantly decreased total fat mass and fat/lean mass tissue ratio in male chow-fed sg/sg mice relative to wt mice. In addition, we observed increased Ucp1 expression in brown adipose and subcutaneous white adipose tissue but not in visceral adipose tissue from Rorα-deficient mice. Moreover, this was associated with significant increases in the expression of the mRNAs encoding the thermogenic genes (i.e., markers of brown and beige adipose) Pparα, Errα, Dio2, Acot11/Bfit, Cpt1ß, and Cidea in the subcutaneous adipose in the sg/sg relative to WT mice. These changes in thermogenic gene expression involved the significantly increased expression of the (cell-fate controlling) histone-lysine N-methyltransferase 1 (Ehmt1), which stabilizes the Prdm16 transcriptional complex. Moreover, primary brown adipocytes from sg/sg mice displayed a higher metabolic rate, and further analysis was consistent with increased uncoupling. Finally, core body temperature analysis and infrared thermography demonstrated that the sg/sg mice maintained greater thermal control and cold tolerance relative to the WT littermates. We suggest that enhanced Ucp1 and thermogenic gene expression/activity may be an important contributor to the lean, obesity-resistant phenotype in Rorα-deficient mice.


Asunto(s)
Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/metabolismo , Regulación de la Expresión Génica/fisiología , Canales Iónicos/metabolismo , Proteínas Mitocondriales/metabolismo , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Obesidad/metabolismo , Termogénesis/fisiología , Absorciometría de Fotón , Animales , Composición Corporal/fisiología , Temperatura Corporal/fisiología , Proteínas de Unión al ADN/metabolismo , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Inmunohistoquímica , Imagen por Resonancia Magnética , Masculino , Ratones , Ratones Mutantes Neurológicos , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , ARN/química , ARN/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Termogénesis/genética , Factores de Transcripción/metabolismo , Proteína Desacopladora 1
18.
World J Gastroenterol ; 20(47): 17851-62, 2014 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-25548483

RESUMEN

AIM: To develop a model of stress-induced senescence to study the hepatocyte senescence associated secretory phenotype (SASP). METHODS: Hydrogen peroxide treatment was used to induce senescence in the human HepG2 hepatocyte cell line. Senescence was confirmed by cytochemical staining for a panel of markers including Ki67, p21, heterochromatin protein 1ß, and senescence-associated-ß-galactosidase activity. Senescent hepatocytes were characterised by gene expression arrays and quantitative polymerase chain reaction (qPCR), and conditioned media was used in proteomic analyses, a human chemokine protein array, and cell migration assays to characterise the composition and function of the hepatocyte SASP. RESULTS: Senescent hepatocytes induced classical markers of senescence (p21, heterochromatin protein 1ß, and senescence-associated-ß-galactosidase activity); and downregulated the proliferation marker, Ki67. Hepatocyte senescence induced a 4.6-fold increase in total secreted protein (P = 0.06) without major alterations in the protein profile. Senescence-induced genes were identified by microarray (Benjamini Hochberg-corrected P < 0.05); and, consistent with the increase in secreted protein, gene ontology analysis revealed a significant enrichment of secreted proteins among inducible genes. The hepatocyte SASP included characteristic factors such as interleukin (IL)-8 and IL-6, as well as novel components such as SAA4, IL-32 and Fibrinogen, which were validated by qPCR and/or chemokine protein array. Senescent hepatocyte-conditioned medium elicited migration of inflammatory (granulocyte-macrophage colony stimulating factor, GM-CSF-derived), but not non-inflammatory (CSF-1-derived) human macrophages (P = 0.022), which could contribute to a pro-inflammatory microenvironment in vivo, or facilitate the clearance of senescent cells. CONCLUSION: Our novel model of hepatocyte senescence provides insights into mechanisms by which senescent hepatocytes may promote chronic liver disease pathogenesis.


Asunto(s)
Senescencia Celular , Quimiotaxis , Hepatocitos/metabolismo , Macrófagos/metabolismo , Comunicación Paracrina , Biomarcadores/metabolismo , Puntos de Control del Ciclo Celular , Senescencia Celular/efectos de los fármacos , Técnicas de Cocultivo , Medios de Cultivo Condicionados/metabolismo , Citocinas/genética , Citocinas/metabolismo , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica , Células Hep G2 , Hepatocitos/efectos de los fármacos , Humanos , Peróxido de Hidrógeno/farmacología , Mediadores de Inflamación/metabolismo , Estrés Oxidativo , Fenotipo , Transcriptoma
19.
Lancet Oncol ; 15(13): 1451-1459, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25456364

RESUMEN

BACKGROUND: Interleukin 6 mediates graft-versus-host disease (GVHD) in experimental allogeneic stem-cell transplantation (allogeneic SCT) and represents an attractive therapeutic target. We aimed to assess whether the humanised anti-interleukin-6 receptor monoclonal antibody, tocilizumab, could attenuate the incidence of acute GVHD. METHODS: We undertook a single-group, single-institution phase 1/2 study at the Royal Brisbane and Women's Hospital Bone Marrow Transplantation unit, QLD, Australia. Eligible patients were 18-65 years old and underwent T-replete HLA-matched allogeneic SCT with either total body irradiation-based myeloablative or reduced-intensity conditioning from unrelated or sibling donors. One intravenous dose of tocilizumab (8 mg/kg, capped at 800 mg, over 60 mins' infusion) was given the day before allogeneic SCT along with standard GVHD prophylaxis (cyclosporin [5 mg/kg per day on days -1 to +1, then 3 mg/kg per day to maintain therapeutic levels (trough levels of 140-300 ng/mL) for 100 days plus methotrexate [15 mg/m(2) on day 1, then 10 mg/m(2) on days 3, 6, and 11]). The primary endpoint was incidence of grade 2-4 acute GVHD at day 100, assessed and graded as per the Seattle criteria. Immunological profiles were compared with a non-randomised group of patients receiving allogeneic SCT, but not treated with tocilizumab. This trial is registered with the Australian and New Zealand Clinical Trials Registry, number ACTRN12612000726853. FINDINGS: Between Jan 19, 2012, and Aug 27, 2013, 48 eligible patients receiving cyclosporin and methotrexate as GVHD prophylaxis were enrolled into the study. The incidence of grade 2-4 acute GVHD in patients treated with tocilizumab at day 100 was 12% (95% CI 5-24), and the incidence of grade 3-4 acute GVHD was 4% (1-13). Grade 2-4 acute GVHD involving the skin developed in five (10%) patients of 48 treated with tocilizumab, involving the gastrointestinal tract in four (8%) patients; there were no reported cases involving the liver. Low incidences of grade 2-4 acute GVHD were noted in patients receiving both myeloablative total body irradiation-based conditioning (12% [95% CI 2-34) and fludarabine and melphalan reduced-intensity conditioning (12% [4-27]). Immune reconstitution was preserved in recipients of interleukin-6 receptor inhibition, but qualitatively modified with suppression of known pathogenic STAT3-dependent pathways. INTERPRETATION: Interleukin 6 is the main detectable and dysregulated cytokine secreted after allogeneic SCT and its inhibition is a potential new and simple strategy to protect from acute GVHD despite robust immune reconstitution; a randomised, controlled trial assessing tocilizumab in addition to standard GVHD prophylaxis in these patients is warranted. FUNDING: National Health and Medical Research Council and Queensland Health.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Neoplasias Hematológicas/complicaciones , Interleucina-6/antagonistas & inhibidores , Trasplante de Células Madre/efectos adversos , Adolescente , Adulto , Anciano , Femenino , Estudios de Seguimiento , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/mortalidad , Neoplasias Hematológicas/mortalidad , Neoplasias Hematológicas/terapia , Humanos , Interleucina-6/inmunología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Prospectivos , Tasa de Supervivencia , Trasplante Homólogo , Adulto Joven
20.
J Invertebr Pathol ; 122: 48-51, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25196471

RESUMEN

The ectoparasitic copepod, Nicothoë astaci (the 'lobster louse'), infests the gills of the European lobster, Homarus gammarus. There have been limited studies on this haematophagous species; therefore knowledge of this parasite is rudimentary. The current study examines the surface morphology of this parasitic copepod, detached from the host, concentrating on adaptations of the suctorial mouthpart, the oral disc. Cryo-scanning electron microscopy revealed structural adaptations that facilitate attachment of these parasites to the gill filaments of their lobster host. The aperture of the feeding channel, through which host haemolymph is drawn, is only ca. 5µm in diameter. The edge of the oral disc is lined with numerous setae, whilst the surface of the disc is covered with large numbers of small (<1µm in diameter) teeth-like structures, which presumably pierce through, and grip, the cuticle lining of the host's gill. Overall, these structures are thought to provide a 'vacuum seal' to assist in pumping of blood, via peristalsis, into the alimentary canal of the copepod host.


Asunto(s)
Copépodos/anatomía & histología , Nephropidae/parasitología , Animales , Microscopía Electrónica de Rastreo
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