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1.
J Virol ; 98(1): e0110223, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38169294

RESUMEN

Mayaro virus (MAYV) is an emerging arbovirus member of the Togaviridae family and Alphavirus genus. MAYV infection causes an acute febrile illness accompanied by persistent polyarthralgia and myalgia. Understanding the mechanisms involved in arthritis caused by alphaviruses is necessary to develop specific therapies. In this work, we investigated the role of the CCL2/CCR2 axis in the pathogenesis of MAYV-induced disease. For this, wild-type (WT) C57BL/6J and CCR2-/- mice were infected with MAYV subcutaneously and evaluated for disease development. MAYV infection induced an acute inflammatory disease in WT mice. The immune response profile was characterized by an increase in the production of inflammatory mediators, such as IL-6, TNF, and CCL2. Higher levels of CCL2 at the local and systemic levels were followed by the significant recruitment of CCR2+ macrophages and a cellular response orchestrated by these cells. CCR2-/- mice showed an increase in CXCL-1 levels, followed by a replacement of the macrophage inflammatory infiltrate by neutrophils. Additionally, the absence of the CCR2 receptor protected mice from bone loss induced by MAYV. Accordingly, the silencing of CCL2 chemokine expression in vivo and the pharmacological blockade of CCR2 promoted a partial improvement in disease. Cell culture data support the mechanism underlying the bone pathology of MAYV, in which MAYV infection promotes a pro-osteoclastogenic microenvironment mediated by CCL2, IL-6, and TNF, which induces the migration and differentiation of osteoclast precursor cells. Overall, these data contribute to the understanding of the pathophysiology of MAYV infection and the identification future of specific therapeutic targets in MAYV-induced disease.IMPORTANCEThis work demonstrates the role of the CCL2/CCR2 axis in MAYV-induced disease. The infection of wild-type (WT) C57BL/6J and CCR2-/- mice was associated with high levels of CCL2, an important chemoattractant involved in the recruitment of macrophages, the main precursor of osteoclasts. In the absence of the CCR2 receptor, there is a mitigation of macrophage migration to the target organs of infection and protection of these mice against bone loss induced by MAYV infection. Much evidence has shown that host immune response factors contribute significantly to the tissue damage associated with alphavirus infections. Thus, this work highlights molecular and cellular targets involved in the pathogenesis of arthritis triggered by MAYV and identifies novel therapeutic possibilities directed to the host inflammatory response unleashed by MAYV.


Asunto(s)
Infecciones por Alphavirus , Artritis , Quimiocina CCL2 , Receptores CCR2 , Animales , Ratones , Alphavirus , Infecciones por Alphavirus/inmunología , Artritis/inmunología , Artritis/virología , Quimiocina CCL2/inmunología , Interleucina-6/inmunología , Ratones Endogámicos C57BL , Receptores CCR2/inmunología , Ratones Noqueados , Masculino , Enfermedades Óseas/virología
2.
Inflamm Res ; 72(4): 859-873, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36912916

RESUMEN

INTRODUCTION: The role of suppressor of cytokine signaling 2 (SOCS2) in Aggregatibacter actinomycetemcomitans (Aa)-induced alveolar bone loss is unknown; thus, it was investigated in this study. METHODS: Alveolar bone loss was induced by infecting C57BL/6 wild-type (WT) and Socs2-knockout (Socs2-/-) mice with Aa. Bone parameters, bone loss, bone cell counts, the expression of bone remodeling markers, and cytokine profile were evaluated by microtomography, histology, qPCR, and/or ELISA. Bone marrow cells (BMC) from WT and Socs2-/- mice were differentiated in osteoblasts or osteoclasts for analysis of the expression of specific markers. RESULTS: Socs2-/- mice intrinsically exhibited irregular phenotypes in the maxillary bone and an increased number of osteoclasts. Upon Aa infection, SOCS2 deficiency resulted in the increased alveolar bone loss, despite decreased proinflammatory cytokine production, in comparison to the WT mice. In vitro, SOCS2 deficiency resulted in the increased osteoclasts formation, decreased expression of bone remodeling markers, and proinflammatory cytokines after Aa-LPS stimulus. CONCLUSIONS: Collectively, data suggest that SOCS2 is a regulator of Aa-induced alveolar bone loss by controlling the differentiation and activity of bone cells, and proinflammatory cytokines availability in the periodontal microenvironment and an important target for new therapeutic strategies. Thus, it can be helpful in preventing alveolar bone loss in periodontal inflammatory conditions.


Asunto(s)
Pérdida de Hueso Alveolar , Enfermedades Periodontales , Ratones , Animales , Pérdida de Hueso Alveolar/genética , Aggregatibacter actinomycetemcomitans/metabolismo , Ratones Endogámicos C57BL , Enfermedades Periodontales/metabolismo , Osteoclastos/metabolismo , Citocinas/metabolismo , Proteínas Supresoras de la Señalización de Citocinas/genética , Proteínas Supresoras de la Señalización de Citocinas/metabolismo
3.
J Virol ; 95(22): e0127621, 2021 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-34495692

RESUMEN

The emergence of life-threatening zoonotic diseases caused by betacoronaviruses, including the ongoing coronavirus disease 19 (COVID-19) pandemic, has highlighted the need for developing preclinical models mirroring respiratory and systemic pathophysiological manifestations seen in infected humans. Here, we showed that C57BL/6J wild-type mice intranasally inoculated with the murine betacoronavirus murine hepatitis coronavirus 3 (MHV-3) develop a robust inflammatory response leading to acute lung injuries, including alveolar edema, hemorrhage, and fibrin thrombi. Although such histopathological changes seemed to resolve as the infection advanced, they efficiently impaired respiratory function, as the infected mice displayed restricted lung distention and increased respiratory frequency and ventilation. Following respiratory manifestation, the MHV-3 infection became systemic, and a high virus burden could be detected in multiple organs along with morphological changes. The systemic manifestation of MHV-3 infection was also marked by a sharp drop in the number of circulating platelets and lymphocytes, besides the augmented concentration of the proinflammatory cytokines interleukin 1 beta (IL-1ß), IL-6, IL-12, gamma interferon (IFN-γ), and tumor necrosis factor (TNF), thereby mirroring some clinical features observed in moderate and severe cases of COVID-19. Importantly, both respiratory and systemic changes triggered by MHV-3 infection were greatly prevented by blocking TNF signaling, either via genetic or pharmacologic approaches. In line with this, TNF blockage also diminished the infection-mediated release of proinflammatory cytokines and virus replication of human epithelial lung cells infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Collectively, results show that MHV-3 respiratory infection leads to a large range of clinical manifestations in mice and may constitute an attractive, lower-cost, biosafety level 2 (BSL2) in vivo platform for evaluating the respiratory and multiorgan involvement of betacoronavirus infections. IMPORTANCE Mouse models have long been used as valuable in vivo platforms to investigate the pathogenesis of viral infections and effective countermeasures. The natural resistance of mice to the novel betacoronavirus SARS-CoV-2, the causative agent of COVID-19, has launched a race toward the characterization of SARS-CoV-2 infection in other animals (e.g., hamsters, cats, ferrets, bats, and monkeys), as well as adaptation of the mouse model, by modifying either the host or the virus. In the present study, we utilized a natural pathogen of mice, MHV, as a prototype to model betacoronavirus-induced acute lung injure and multiorgan involvement under biosafety level 2 conditions. We showed that C57BL/6J mice intranasally inoculated with MHV-3 develops severe disease, which includes acute lung damage and respiratory distress that precede systemic inflammation and death. Accordingly, the proposed animal model may provide a useful tool for studies regarding betacoronavirus respiratory infection and related diseases.


Asunto(s)
Infecciones por Coronavirus/patología , Modelos Animales de Enfermedad , Pulmón/patología , Virus de la Hepatitis Murina/patogenicidad , Animales , Línea Celular , Contención de Riesgos Biológicos , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/virología , Citocinas/metabolismo , Humanos , Inflamación , Hígado/patología , Hígado/virología , Pulmón/virología , Ratones , Virus de la Hepatitis Murina/efectos de los fármacos , Virus de la Hepatitis Murina/fisiología , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/patogenicidad , SARS-CoV-2/fisiología , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/metabolismo , Replicación Viral/efectos de los fármacos
4.
Biomed Mater ; 15(5): 055023, 2020 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-32375130

RESUMEN

Osteoporosis is a metabolic disease that affects bone tissue and is highly associated with bone fractures. Typical osteoporosis fracture treatments, such as bisphosphonates and hormone replacement, present important challenges because of their low bioavailability on the site of action. Options to overcome this issue are systems for the local release of therapeutic agents such as bioactive glasses containing therapeutic molecules and ions. These agents are released during the dissolution process, combining the drugs and ion therapeutic effects for osteoporosis treatment. Among the therapeutic agents that can be applied for bone repair are strontium (Sr) ion and phytopharmaceutical icariin, which have shown potential to promote healthy bone marrow stem cells osteogenic differentiation, increase bone formation and prevent bone loss. Submicron Sr-containing bioactive glass mesoporous spheres with sustained ion release capacity were obtained. Icariin was successfully incorporated into the particles, and the glass composition influenced the icariin incorporation efficiency and release rates. In this work, for the first time, Sr and icariin were incorporated into bioactive glass submicron mesoporous spheres and the in vitro effects of the therapeutic agents release were evaluated on the reduced osteogenic potential of rat osteoporotic bone marrow mesenchymal stem cells, and results showed an improvement on the reduced differentiation potential.


Asunto(s)
Células de la Médula Ósea/citología , Cerámica , Sistemas de Liberación de Medicamentos , Flavonoides/administración & dosificación , Células Madre Mesenquimatosas/citología , Osteoporosis/tratamiento farmacológico , Fitoterapia/métodos , Estroncio/química , Animales , Células Cultivadas , Femenino , Técnicas In Vitro , Iones , Microscopía de Fuerza Atómica , Microesferas , Osteogénesis , Tamaño de la Partícula , Fenotipo , Fitoquímicos/química , Ratas , Ratas Wistar , Espectroscopía Infrarroja por Transformada de Fourier
5.
J Mater Sci Mater Med ; 30(7): 86, 2019 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-31302783

RESUMEN

Bioactive glasses (BGs) are widely used for bone regeneration, and allow the incorporation of different ions with therapeutic properties into the glass network. Amongst the different ions with therapeutic benefits, manganese (Mn) has been shown to influence bone metabolism and activate human osteoblasts integrins, improving cell adhesion, proliferation and spreading. Mn has also been incorporated into bioceramics as a therapeutic ion for improved osteogenesis. Here, up to 4.4 mol% MnO was substituted for CaO in the 58S composition (60 mol% SiO2, 36 mol% CaO, 4 mol% P2O5) and its effects on the glass properties and capability to influence the osteogenic differentiation were evaluated. Mn-containing BGs with amorphous structure, high specific surface area and nanoporosity were obtained. The presence of Mn2+ species was confirmed by X-ray photoelectron spectroscopy (XPS). Mn-containing BGs presented no cytotoxic effect on human mesenchymal stem cells (hMSCs) and enabled sustained ion release in culture medium. hMSCs osteogenic differentiation stimulation and influence on the mineralisation process was also confirmed through the alkaline phosphatase (ALP) activity, and expression of osteogenic differentiation markers, such as collagen type I, osteopontin and osteocalcin, which presented higher expression in the presence of Mn-containing samples compared to control. Results show that the release of manganese ions from bioactive glass provoked human mesenchymal stem cell (hMSC) differentiation down a bone pathway, whereas hMSCs exposed to the Mn-free glass did not differentiate. Mn incorporation offers great promise for obtaining glasses with superior properties for bone tissue regeneration.


Asunto(s)
Cerámica/farmacología , Manganeso/química , Osteogénesis/fisiología , Transición de Fase , Fosfatasa Alcalina/metabolismo , Células de la Médula Ósea/citología , Regeneración Ósea , Calcificación Fisiológica/efectos de los fármacos , Adhesión Celular , Diferenciación Celular , Proliferación Celular , Vidrio , Humanos , Iones , Ensayo de Materiales , Microscopía Fluorescente , Osteoblastos/citología , Dióxido de Silicio/química , Espectroscopía Infrarroja por Transformada de Fourier
6.
J Biomed Mater Res B Appl Biomater ; 100(5): 1387-96, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22566477

RESUMEN

The development of polymer/bioactive glass has been recognized as a strategy to improve the mechanical behavior of bioactive glass-based materials. Several studies have reported systems based on bioactive glass/biopolymer composites. In this study, we developed a composite system based on bioactive glass nanoparticles (BGNP), obtained by a modified Stöber method. We also developed a new chemical route to obtain aqueous dispersive biodegradable polyurethane. The production of polyurethane/BGNP scaffolds intending to combine biocompatibility, mechanical, and physical properties in a material designed for tissue engineering applications. The composites obtained were characterized by structural, biological, and mechanical tests. The films presented 350% of deformation and the foams presented pore structure and mechanical properties adequate to support cell growth and proliferation. The materials presented good cell viability and hydroxyapatite layer formation upon immersion in simulated body fluid.


Asunto(s)
Sustitutos de Huesos/química , Vidrio/química , Ensayo de Materiales , Nanopartículas/química , Poliuretanos/química , Andamios del Tejido/química , Animales , Sustitutos de Huesos/síntesis química , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Osteoblastos/citología , Poliuretanos/síntesis química , Porosidad , Ratas , Ingeniería de Tejidos/métodos
7.
J Feline Med Surg ; 13(8): 546-52, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21530343

RESUMEN

The purpose of this study was to evaluate the tissue response to a 70% polyhydroxybutyrate and 30% hydroxyapatite composite in the form of a bone implant, placed intracortically in the distal metaphyseal of the right femur, and subcutaneous implants in cats. Samples of the composite were implanted subcutaneously in the dorsolumbar region and the distal metaphyseal region of the right femur of the animals. The study used 12 neutered adult mixed breed cats, weighing an average of 3.5kg. The cats were randomly divided into three groups: GI, GII and GIII, according to the length of the assessment period. The assessments of their subcutaneous and bone tissues were performed at 15, 30 and 45 days and at 30, 60 and 90 days, respectively. The subcutaneous and bone reactions to the composites were characterized by granulomatous inflammation with a predominance of macrophages and giant cells. The results showed that the composites triggered a chronic local inflammatory response, despite their clinical acceptance.


Asunto(s)
Sustitutos de Huesos/efectos adversos , Sustitutos de Huesos/uso terapéutico , Gatos/cirugía , Durapatita/efectos adversos , Fémur/patología , Fémur/cirugía , Hidroxibutiratos/efectos adversos , Animales , Materiales Biocompatibles/efectos adversos , Durapatita/inmunología , Durapatita/uso terapéutico , Fémur/diagnóstico por imagen , Curación de Fractura , Hidroxibutiratos/inmunología , Hidroxibutiratos/uso terapéutico , Masculino , Necrosis , Prótesis e Implantes/veterinaria , Radiografía , Distribución Aleatoria
8.
Rio de Janeiro; Cultura Médica; 2006. 538 p. ilus, map, tab, graf.
Monografía en Portugués | Coleciona SUS | ID: biblio-924892
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