Duchenne muscular dystrophy: RANK/RANKL/OPG (receptor activator of nuclear factor-kB/RANK ligand/osteoprotegerin) system and glucocorticoids / Distrofia muscular de Duchenne: el sistema RANK/RANKL/OPG (receptor activador del factor nuclear-kB/ligando de RANK/osteoprotegerina) y glucocorticoides

Abstract Duchenne muscular dystrophy (DMD) is an X-linked inherited disorder. Patients present with decreased bone mineral density (BMD) due to glucocorticoid therapy and progressive muscle weakness. Bone remodeling allows bone volume and structure to be maintained and controlled by local and systemic factors. These include the receptor activator of the nuclear factor-kB (RANK)/RANK ligand (RANKL)/osteoprotegerin (OPG) system, a determining pathway in the balance between bone formation and resorption. Disruptions in this complex, caused by factors such as glucocorticoids, can affect bone metabolism. The extensive action of the RANK/RANKL/OPG pathway suggests an influence on dystrophic muscle pathophysiology. This review aimed to highlight some aspects of the RANK/RANKL/OPG system, the effect of glucocorticoids on this pathway, and the pathophysiology of the patient with DMD.

Resumen La distrofia muscular de Duchenne (DMD) es un trastorno hereditario ligado al cromosoma X. Los pacientes presentan una disminución de la densidad mineral ósea (DMO) debido a los efectos adversos del tratamiento con glucocorticoides y a la debilidad muscular progresiva. El remodelado óseo permite mantener el volumen y la estructura ósea, proceso controlado por factores locales y sistémicos. Entre ellos destaca el sistema del receptor activador del factor nuclear-kB (RANK), su ligando natural RANKL (RANKL) y la osteoprotegerina (OPG), una vía determinante en el equilibrio entre la resorción y formación ósea. Las alteraciones en este complejo, originadas por factores como los glucocorticoides, pueden afectar el metabolismo óseo. La amplia acción de RANKL y OPG ha sugerido una influencia en la fisiopatología de la DMD. El objetivo de esta revisión fue destacar algunos aspectos del sistema RANK/RANKL/OPG, el efecto de los glucocorticoides en esta vía y la fisiopatología del paciente con DMD.

Tumor adenomatoide de tubas uterinas, reporte de un caso y revisión de la literatura / Adenomatoid uterine tube tumor, case report and literature review

Resumen Los tumores adenomatoides del tracto genital son neoplasias poco frecuentes, de comportamiento benigno; debido a sus características histológicas se confunden fácilmente con tumores de estirpe vascular. Estudios recientes demuestran que los tumores adenomatoides del tracto genital femenino están genéticamente definidos por la mutación TRAF7 que activa la expresión aberrante de la vía NFkB. Presentamos el caso de una mujer de 27 años, asintomática, a quien se le realiza salpingectomía bilateral como método de anticoncepción definitivo; en el examen macroscópico de la tuba derecha se encuentra formación quística que por sus características microscópicas es diagnosticada como tumor adenomatoide de la tuba uterina. Finalmente se realiza una revisión de la literatura.

Abstract The adenomatoid tumors of the genital tract are rare neoplasms, with benign behavior; due to their histological characteristics, they are easily confused with tumors of vascular origin. Recent studies show that adenomatoid tumors of the female genital tract are genetically defined by the TRAF7 mutation that activates the aberrant expression of the NFkB pathway. We present the case of a 27-year-old woman, asymptomatic, who underwent bilateral salpingectomy as a method of definitive contraception; In the macroscopic examination of the right tuba, cystic formation is found which, due to its microscopic characteristics, is diagnosed as an adenomatoid tumor of the uterine tube. Finally, a review of the literature is made

Anquilose da articulação temporomandibular na infância: análise da expressão gênica da osteoprotegerina e do ligante do fator ativador do receptor nuclear kappa-b / Temporomandibular joint ankylosis in childhood: analysis of osteoprotein gene expression and kappa-b nuclear receptor activator factor ligand

A anquilose da articulação temporomandibular (AATM) apesar de rara, é uma doença grave e de difícil tratamento, que restringe os movimentos articulares acarretando ao paciente problemas estéticos, nutricionais, psicológicos e sociais. A formação do bloco ósseo anquilótico determina a gravidade da doença. O remodelamento ósseo é um mecanismo coordenado e extremamente complexo responsável pela formação e pela reabsorção óssea, sendo necessário no reparo de trauma ósseo e na manutenção da homeostasia do metabolismo mineral. Assim, entender o processo de remodelamento ósseo envolvido na fisiopatologia das AATMs pode trazer perspectivas no tratamento desta doença. O objetivo do estudo foi avaliar o perfil de expressão dos genes envolvidos no remodelamento ósseo, osteoprotegerina (OPG) e do fator ativador do receptor nuclear kappa-B/ligante (RANKL), em amostras de crianças com AATM para verificar se existe associação com a degeneração articular da ATM. Foram incluídos no estudo 11 crianças com diagnóstico de AATM e 5 amostras de osso controle (sem alteração patológica na ATM). A idade média dos pacientes com AATM foi de 12 anos, sendo que 9 (82%) já haviam realizado cirurgia prévia de AATM, 36% (n = 4) apresentaram otite em fase neonatal e 18% (n = 2) infecção prévia. A expressão de OPG e RANKL foi avaliada pela reação em cadeia da polimerase quantitativa. Foi observado uma menor expressão de OPG e RANKL nas amostras de pacientes com AATM (bloco anquilótico e osso adjacente à anquilose) comparado as amostras controle. O RANKL e OPG regulam a reabsorção óssea por estimulação do RANK em células precursoras de osteoclastos. Nossos resultados são corroborados por um estudo recente, justificando a investigação da via RANK-RANKL-OPG na AATM, com o intuito de se explorar novas possibilidades terapêuticas, que possam auxiliar no tratamento desta doença que ainda é negligenciada. A menor expressão de OPG e RANKL indicam que a patogênese da AATM em crianças está relacionada a diminuição da reabsorção óssea.

Temporomandibular joint ankylosis (TMJA), although rare, is a serious and difficult to treat disease, which restricts joint movements, causing aesthetic, nutritional, psychological and social problems to the patient. The formation of the ankylotic bone block determines the severity of the disease. Bone remodeling is a coordinated and extremely complex mechanism responsible for bone formation and resorption, and is necessary for the repair of bone trauma and the maintenance of homeostasis of mineral metabolism. Thus, understanding the process of bone remodeling involved in the pathophysiology of TMJA may bring perspectives in the treatment of this disease. The aim of the study was to evaluate the expression profile of the genes involved in bone remodeling, osteoprotegerin (OPG) and nuclear kappa-B receptor activator / RANKL (RANKL) in samples from children with TMJA to verify if there is association with Joint degeneration of TMJ. The study included 11 children with TMJA diagnosis and 5 control bone samples (without pathological alterations in TMJ). The mean age of patients with TMJA was 12 years, and 9 (82%) had previously performed TMJA surgery, 36% (n = 4) presented otitis in the neonatal phase and 18% (n = 2) had previous infection. The expression of OPG and RANKL was evaluated by the quantitative polymerase chain reaction. Lower expression of OPG and RANKL was observed in the samples of patients with TMJA (ankylotic block and bone adjacent to ankylosis) compared to the control samples. RANKL and OPG regulate bone resorption by stimulating RANK in osteoclast precursor cells. Our results are corroborated by a recent study, justifying the investigation of the RANK-RANKL-OPG pathway in the TMJA, in order to explore new therapeutic possibilities that may help in the treatment of this disease that is still neglected. Lower expression of OPG and RANKL indicate that pathogenesis of TMJA in children is related with lower bone resorption.

Effects of Cinnamon extract on biochemical enzymes, TNF-α and NF-κB gene expression levels in liver of broiler chickens inoculated with Escherichia coli / Efeitos de extrato de canela sobre os níveis de enzimas bioquímicos, e expressão de genes de TNF-α e NF-κB em fígado de frangos de corte inoculadas com Escherichia coli

Infection with Escherichia coli (E. coli) is a common disease in poultry industry. The use of antibiotics to treat diseases is facing serious criticism and concerns. The medicinal plants may be effective alternatives because of their multiplex activities. The aim of this study was to investigate the effects of cinnamon extract on the levels of liver enzymes, tumor necrosis factor-alpha (TNF-α) and nuclear factor-kappa B (NF-κB) gene expressions in liver of broiler chickens infected with E. coli. Ninety Ross-308 broilers were divided into healthy or E. coli-infected groups, receiving normal or cinnamon extract (in concentrations of 100 or 200mg/kg of food) supplemented diets. E. coli suspension (108cfu) was injected subcutaneously after 12 days cinnamon administration. Seventy-two hours after E. coli injection, the blood samples were taken for biochemical analysis of liver enzymes in serum (spectrophotometrically), and liver tissue samples were obtained for detection of gene expression of inflammatory markers TNF-α and NF-κB, using real-time PCR. Infection with E. coli significantly increased the levels of TNF-α and NF-κB gene expressions as well as some liver enzymes including creatine-kinase (CK), lactate-dehydrogenase (LDH), alanine-transferase (ALT) and aspartate-transferase (AST) as compared with control group (P<0.05). Pre-administration of cinnamon extract in broilers diet (in both concentrations) significantly reduced the tissue levels of TNF-α and NF-κB gene expressions and enzymes CK and ALT in serum of broiler chickens inoculated with E. coli in comparison with E. coli group (P<0.05 and P<0.01). The levels of LDH and AST were significantly decreased only by 200mg/kg cinnamon extract in infected broilers. The level of alkaline-phosphatase (ALP) was not affected in any groups. Pre-administration of cinnamon extract in diets of broiler chickens inoculated with E. coli could significantly reduce the gene expression levels...

Infecção ocasionada por Escherichia coli (E. coli) é uma enfermidade comum na indústria avícola. O uso de antibióticos para tratar doenças bacterianas vem enfrentando sérias críticas e preocupações. As plantas medicinais podem ser alternativas eficazes por causa de suas atividades sinérgicas. O objetivo deste estudo foi investigar os efeitos do extrato de canela sobre os níveis de as enzimas hepáticas bem como sobre a expressão dos genes relativos, fator de necrose tumoral-alfa (TNF-α) e fator nuclear -kappa B (NF-κB) em fígado de frangos de corte infectados com E. coli. Noventa frangos Ross-308 foram divididos em grupos saudáveis ou infectados com E. coli, que receberam dietas controle ou com suplementação contendo extrato de canela (em concentrações de 100 ou 200 mg/kg de alimento). Suspensão de E. coli (108UFC) foi injetado por via subcutânea, após 12 dias de administração do extrato de canela. Setenta e duas horas após a injeção de E. coli, amostras de sangue foram colhidas para análise bioquímica das enzimas do fígado no soro (espectrofotometria), e amostras de tecido de fígado foram obtidas para a determinação da expressão de genes de marcadores inflamatórios TNF-α e NF-κB, através PCR em tempo real. A infecção com E. coli aumentou significativamente os níveis de expressão dos genes TNF-α e NF-κB, assim como algumas enzimas hepáticas, incluindo creatina-quinase (CK), lactato-desidrogenase (LDH), alanina-transferase (ALT) e aspartato-transferase (AST), em comparação com o grupo de controle (P<0.05). A pré-administração do extrato de canela na dieta dos frangos (em ambas as concentrações) reduziu significativamente os níveis de expressão tecidual de TNF-α e NF-kB, da mesma forma que das enzimas CK e ALT no soro de frangos infectados com E. coli, em comparação com o grupos somente infectado com E. coli (P<0.05 e P<0.01). Os níveis de LDH e AST foram significativamente menores apenas para o grupo suplementado com extrato de canela na concentração...

Papel do fator nuclear kappa B (NF-κB) na expressâo do gene NCF1 em leucócitos de indivíduos normais, e pacientes com doença granulomatosa crônica, displasia ectodérmica anidrótica, ou com defeitos no eixo IL-12/23-IFN-γ / Role of nuclear factor kappa B (NF-κB) on NCF1 gene expression in leukocytes from normal individuals, and patients with chronic granulomatous disease, anhidrotic ectodermal dysplasia, or with defects in the IL-12/23/IFN-γ axis

Objetivo: Analisamos a relevância do NF-κB sobre a expressão do gene NCF1 em células mielóides U937 selvagens (U937) ou transfectadas com um repressor do NF-κB (IκBα-S32A/S36A - U937 IκBα-S32A/S36A) ou transfectadas com o vetor vazio (U937 pCMV3) e em células B imortalizadas pelo vírus Epstein-Barr (EBV) de pacientes com displasia ectodérmica anidrótica com imunodeficiência (EDA-ID) ou com doença granulomatosa crônica (CGD) devido a mutações no gene NCF1, ou de pacientes portadores de defeitos do eixo IL-12/ 23-IFN-γ. Métodos: O RNA celular total foi isolado pelo método TRI-zol®. Os cDNAs foram produzidos utilizando-se o SuperScript™ III e amplificados por Real-time PCR (SYBR® Green Master Mix). Resultados: Células U937 IKBα-S32A/S36A mostraram significante decréscimo na expressão do gene NCF1 comparadas com as células U937. A expressão do gene NCF1 em células EDA-ID S32I foi significativamente menor que em controles saudáveis, assim como em células EDA-ID NEMO/IKKγ X420W na mesma comparação. Estes resultados foram similares aos encontrados em células de pacientes CGD devido à mutação autossômica recessiva no gene NCF1 quando comparados com o controle normal. Defeitos nos receptores IFNGR1 e IFNGR2 levam à diminuição da expressão do gene NCF1 (p<0,05, Mann Whitney). Conclusões: Estes resultados mostram que o NF-κB é necessário para a expressão do gene NCF1, que possivelmente as subunidades p50 e/ou p65 do NF-κB ligam-se funcionalmente à região "upstream" do gene NCF1 e que defeitos no eixo IL-12/ 23-IFN-γ influenciam a expressão do gene NCF1.

Objective: We analyzed the relevance of NF-κB on NCF1 gene expression in regular myeloid U937 cells (U937), or transfected with a NF-κB repressor (IκBo-S32A/S36A - U937 IκBo-S32A/S36A), or transfected with the empty vector (U937 pCMV3), and in B cells immortalized by Epstein-Barr vírus (EBV) from patients with anhidrotic ectodermal dysplasia with immunodeficiency (EDA-ID), or with chronic granulomatous desease (CGD) due to mutations in NCF1 gene, or from patients with IL-12/23-IFN-γ axis defects. Methods: Total RNA was isolated by the TRIzol® method. The cDNAs were produced by Super Script™ III and amplified by Real-time PCR (SYBR Green Master Mix). Results: U937 IκBo-S32A/S36A cells showed significant decrease in the NCF1 gene expression compared with the U937 cells. The NCF1 gene expression was significantly lower in EDA-ID S32I cells compared to healthy controls as well as in EDA-ID NEMO/IKKy X420W cells. These results were similar to those obtained in the CGD patient cells due recessive mutations in the NCF1 gene compared to healthy controls. Cells form patients with defects in IFNGR1 e IFNGR2 receptors also presented decreased NCF1 gene expression (p<0,05, Mann Whitney). Conclusion: These results show that the NF-κB is necessary for NCF1 expression, possibly the p50 and/or p65 NF-κB subunits bind functionally to the upstream region of the NCF1 gene and that IL-12/23-IFN-γ axis defects also influence NCF1 gene expression.

Papel das proteínas intracelulares nod e da proteína adaptadora myD88 na regulação de espressão de RANKL e modulação da resposta inflamatória induzidos por antígenos bacterianos in vitro: estudo em células relevantes de periodonto / Role of nod an myD88 proteins on the regulation of bacterial antigen-induced expression of RANKL and on the modulation of inflammation: a study on relevant cells of the periodontium

A reabsorcao do osso alveolar e uma das principais caracteristicas associadas a progressao da doenca periodontal. Apesar da enorme complexidade da microbiota envolvida, considera-se que bacterias Gram-negativas tenham um papel relevante em sua etiopatogenese. Um dos fatores de virulencia destes microrganismos e representado por um componente de sua parede externa denominado lipopolissacarideo (LPS). A presenca de LPS na proximidade dos tecidos periodontais e capaz de induzir a producao de diversos mediadores inflamatorios que levam a degradacao tanto do tecido conjuntivo quanto osseo. Atualmente acredita-se que a interacao do ligante do receptor-ativador do fator nuclear kappa-B (RANKL) com seu receptor (RANK) presente em precursores hematopoieticos e necessaria e suficiente para a inducao da diferenciacao de osteoclastos. Por outro lado, a ligacao de RANKL com seu falso-receptor, denominado osteoprotegerina (OPG), reduz sua biodisponibilidade e inibe, desta forma, a osteoclastogenese. Assim, a razao da expressao de RANKL e OPG e considerada como o principal determinante do “turnover” do tecido osseo. A producao de RANKL e OPG depende das vias de sinalizacao ativadas, as quais sao influenciadas pela natureza do estimulo extracelular. Atualmente, a familia de receptores NLRs (nod-like receptors) foi identificada como receptor intracelular para componentes bacterianos e agentes moduladores de diferentes vias de sinalizacao. Considerando a relevancia do LPS bacteriano na patogenese da doenca periodontal, o papel do RANKL no processo de reabsorcao ossea e a possivel implicacao das proteinas Nod na transducao de sinais regulando a expressao de RANKL, o objetivo geral deste projeto foi estudar os mecanismos de regulacao da expressao de RANKL induzido por LPS bacteriano em celulas relevantes do periodonto (macrofagos, osteoblastos e fibroblastos). Os objetivos especificos propostos...

Bone resorption is one of the major characteristics of destructive periodontal disease. Despite the great number of different bacterial species in the dental biofilm, Gramnegative microorganisms were demonstrated to have a very important role on periodontal disease pathogenesis. Lipopolysaccharide (LPS) is a bacterial cell wall component, which is acknowledged as one of the main virulence factors of these microorganisms. The mere presence of LPS in proximity with the periodontal tissues initiates the expression and production of inflammatory mediators and other cytokines which can culminate in degradation of both soft and hard tissues. It is currently accepted that the interaction between receptor-activator of nuclear factor kappa-B ligand (RANKL) and its receptor (RANK) is both necessary and sufficient to induce osteoclast differentiation and activation. However, RANKL can interact with its soluble decoy receptor osteoprotegerin (OPG) inhibiting osteoclastogenesis by decreasing the bioavailability of RANKL. Production of RANKL/OPG is the result of the signaling pathways activated by external stimuli. Recently, the NLR (nod-like receptors) family was identified as cytosolic receptors for bacterial components and also, as capable of modulating different signaling pathways. Considering the relevance of LPS and RANKL in bone resorption and the possible implication of Nod proteins in signal transduction regulating RANKL expression, the aim of this study was to evaluate the influence of different intracellular signaling pathways on the regulation of RANKL expression induced by LPS in relevant cells of the periodontium (macrophages, osteoblasts and fibroblasts). The specific objectives proposed were to determine after LPS and interleukin-1 beta stimulation the role of MyD88-dependent and independent signaling pathways, Nod1 and Nod2 on the expression of RANKL, OPG, IL-10 and IFN-beta...

El papel del factor de transcripción NF-κB en la célula cardíaca / Role of the transcription factor NF-κB in the cardiac cell

Para la biología de hoy las vías de señalización intracelular que controlan los procesos entre la vida y la muerte celular son de gran interés. Al respecto, el NF-κB destaca como un factor de transcripción decisivo de respuesta rápida que participa en la activación de las vías de señalización de la muerte celular programada. Lo relevante es que sus efectos tienen consecuencias en el desarrollo normal y/o la homeostasis en muchas células o tejidos, que incluyen entre otros al sistema inmune, los folículos capilares, apéndices epidermales, el riñon y el sistema nervioso. En esta revisión analizamos el papel central que juega el factor de transcripción NF-κB en el funcionamiento normal de la célula cardíaca y sus implicaciones en algunas de las patologías cardíacas más frecuentes como: el daño por isquemia-reperfusión, la isquemia precondicionada, la hipertrofia, la aterosclerosis, y el paro cardíaco. El NF-κB comúnmente funciona como un agente citoprotector, aunque hay algunos casos en los cuales resulta ser pro-apoptótico dependiendo del estímulo y del contexto celular. Se han logrado avances significativos a nivel molecular, que han permitido entender su modo de acción y el papel interactivo que juega con otros factores claves. Estos estudios han identificado muchos genes anti-apoptóticos y pro-apoptóticos regulados por la actividad del NF-κB abriendo novedosas aproximaciones que se pueden hacer sobre sus efectos en el desarrollo de patologías cardíacas.

The signaling pathways that control the life-death switch of a cell are a prime interest in Modern Biology. To this respect, NF-κB has emerged as a decisive transcription factor in the cell's response to apoptotic challenge and its effects on apoptosis have far-reaching consequences for normal development and/or homeostasis in many cells and tissues, including the immune system, hair follicles, and epidermal appendages, the liver, and nervous system. In this review we analyze the pivotal role of the transcription factor NF-κB in the normal functioning of the cardiac cell and its implication on some of the most frequent cardiac pathologies, such as ischemia-reperfusion injury, ischemic precondition, hypertrophy, atherosclerosis and cardiac arrest. While NF-κB is commonly found to be cytoprotective, there are a number of instances where it is proapoptotic depending on the inducing stimulus and the cell context. Significant progress has been made in understanding its mode of action and its interplay with other key factors. These studies identified many anti- and pro-apoptotic NF-κB regulated genes that mediate its activity, these important new insights fuel hope that novel approaches will be developed to control the effects of NF-κB in cardiac pathologies.

Inhibition of Inducible Nitric Oxide Synthase Expression by YS 49, a Synthetic Isoquinoline Alkaloid, in ROS 17/2.8 Cells Activated with TNF-alpha, IFN-gamma and LPS

Nitric oxide (NO) has been suggested to act as a mediator of cytokine-induced effects of turn over of bone. Activation of the inducible nitric oxide synthase (iNOS) by inflammation has been related with apoptotic cell death in osteoblast. YS 49, a synthetic isoquinoline alkaloid, inhibits NO production in macrophages activated with cytokines. In the present study, we investigated the molecular mechanism of YS 49 to inhibit iNOS expression in ROS 17/2.8 cells, which were activated with combined treatment of inflammatory cytokines (TNF-alpha, IFN-gamma) and lipopolysaccharide (LPS). Results indicated that YS 49 concentration-dependently reduced iNOS mRNA and protein expression, as evidenced by Northern and Western blot analysis, respectively. The underlying mechanism by which YS 49 suppressed iNOS expression was not to affect iNOS mRNA stability but to inhibit activation and translocation of NF-kappaB by preventing the degradation of its inhibitory protein IkappaBalpha. As expected, YS 49 prevented NO-induced apoptotic cell death by sodium nitroprusside. Taken together, it is concluded that YS 49 inhibits iNOS expression by interfering with degradation of phosphorylated inhibitory kappaBalpha (p-IkappaBalpha). These actions may be beneficial for the treatment of inflammation of the joint, such as rheumatoid arthritis.