Expressions of TOLL-like receptor 4 (TLR-4) and matrix metalloproteinase 9 (MMP-9)/Tissue inhibitor of metalloproteinase 1 (TIMP-1) in pulmonary blood vessels with chronic obstructive pulmonary diseases and their relationships with pulmonary vascular remodelling

SUMMARY OBJECTIVE: This study aims at investigating the expressions of TOLL-like receptor 4 (TLR-4) and matrix metalloproteinase 9 (MMP-9)/ tissue inhibitor of metalloproteinase 1 (TIMP-1) in pulmonary blood vessels with chronic obstructive pulmonary disease (COPD) and their relationships with pulmonary vascular remodelling (PVR). METHODS: 60 para-tumour tissues were divided into the COPD group and the control group (n=30); the inflammations, pulmonary artery wall area/total artery area (WA%), and wall thickness/vascular outer diameter (WT%) were compared. The expressions of TLR-4, MMP-9/TIMP-1, and PCNA in pulmonary vascular smooth muscle cells were detected, and their relationships with PVR were then analysed. RESULTS: The inflammations (1.6±0.8), WA% (44.0±6.4), and WT% (27.3±3.3) in the COPD group were higher than in the control group (0.3±0.5, 26.1±2.8, 15.6±1.8), and the expressions of TLR-4 (31.4±147) and MMP-9/TIMP-1 (2.2±2.6) were increased compared to the control group (4.7±4.5, 1.9±12). Correlation analysis: TLR-4 and MMP-9/TIMP-1 were positively correlated with the inflammations (r=0.18, P<0.01), WA% (r=0.68, P<0.01), and WT% (r=0.73, P<0.01), as well as positively correlated with the expression of PCNA (r=0.44, P<0.01); the upregulation of TLR-4 was positively correlated with the expressions of MMP-9 and TIMP-1. CONCLUSIONS: The upregulation of TLR-4 in the pulmonary arterial smooth muscle cells of COPD patients could promote the inflammations and the MMP-9 expression, thus causing abnormal degradation of extracellular matrix, so it played an important role in the process of PVR.

RESUMO OBJETIVO: Este estudo tem como objetivo investigar as expressões de TOLL-like receptor 4 (TLR-4) e metaloproteinase 9 da matriz (MMP-9)/inibidor de tecido da metaloproteinase 1 (TIMP-1) em vasos sanguíneos pulmonares com doença pulmonar obstrutiva crônica (DPOC) e suas relações com o remodelamento vascular pulmonar (PVR). MÉTODOS: Sessenta tecidos paratumorais foram divididos em grupo COPD e o grupo controle (n = 30). Foram comparadas as inflamações, área da parede da artéria pulmonar/área da artéria total (WA%) e espessura da parede/diâmetro externo vascular (WT%). As expressões de TLR-4, MMP-9/TIMP-1 e PCNA em células de músculo liso vascular pulmonar foram detectadas, e suas relações com PVR foram então analisadas. RESULTADOS: As inflamações (1,6 ± 0,8), WA% (44,0 ± 6,4) e WT% (27,3 ± 3,3) no grupo COPD foram maiores que no grupo controle (0,3 ± 0,5; 26,1 ± 2,8; 15,6 ± 1,8). E as expressões de TLR-4 (31,4 ± 14,7) e MMP-9/TIMP-1 (2,2 ± 2,6) foram aumentadas em relação ao grupo controle (4,7 ± 4,5, 1,9 ± 1,2). Na análise de correlação, TLR-4 e MMP-9/TIMP-1 foram positivamente correlacionadas com as inflamações (r = 0,18; P <0,01), WA% (r = 0,68; P <0,01) e WT% (r = 0,73; P <0,01), bem como correlacionadas positivamente com a expressão de PCNA (r = 0,44; P <0,01). A elevação da TLR-4 foi correlacionada positivamente com as expressões de MMP-9 e TIMP-1. CONCLUSÕES: A regulação positiva do TLR-4 nas células do músculo liso arterial pulmonar de pacientes com DPOC poderia promover as inflamações e a expressão de MMP-9, causando assim uma degradação anormal da matriz extracelular, por isso desempenhou um papel importante no processo de PVR.

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...