RESUMO
Abnormal pressure is an important factor that contributes to bone adaptation in the temporomandibular joint (TMJ). We determined the effect of the mitogen-activated protein kinases (MAPK) pathway on the pressure-induced synovial metaplasia procedure for the TMJ, both in vitro and in vivo. Synovial fibroblasts (SFs) were exacted from rat TMJs and exposed to different hydrostatic pressures. The protein extracts were analyzed to determine the activation of ERK1/2, JNK, and p38. Surgical anterior disc displacement (ADD) was also performed on Japanese rabbits, and the proteins of TMJ were isolated to analyze pressure-induced MAPK activation after 1, 2, 4, and 8 weeks. The results showed that the activation of ERK1/2 and JNK in SFs significantly changed with increasing hydrostatic pressure, whereas p38 activation did not change. Moreover, p38 was activated in animals 1 week after surgical ADD. The levels of p38 gradually increased after 2 and 4 weeks, and then slightly decreased but remained higher than in the control 8 weeks after surgical ADD. Nevertheless, JNK was rarely activated after the ADD treatment. Our findings suggest the involvement of MAPK activation in the pressure-induced synovial metaplasia procedure with pressure loading in TMJ.
Assuntos
Sistema de Sinalização das MAP Quinases , Transtornos da Articulação Temporomandibular/metabolismo , Articulação Temporomandibular/patologia , Animais , Células Cultivadas , Fibroblastos/metabolismo , Pressão Hidrostática/efeitos adversos , Cápsula Articular/metabolismo , Cápsula Articular/patologia , Metaplasia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Coelhos , Ratos , Ratos Sprague-Dawley , Articulação Temporomandibular/metabolismo , Transtornos da Articulação Temporomandibular/etiologia , Transtornos da Articulação Temporomandibular/patologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
The effect of sinomenine (SIN) on the toll-like receptor (TLR) signal transduction pathway as well as the expression of myeloid differentiation factor 88 (MyD88) and tumor necrosis factor (TNF) receptor-associated factor-6 (TRAF6) was investigated. SIN inhibition of rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS) proliferation and RA cartilage and subchondral bone destruction was also investigated. RA-FLS were cultured in vitro and the intracellular alkaline phosphatase (ALP) activity was determined in order to obtain the optimal drug concentration. The rate of cell proliferation was determined. Fluorescence quantitative polymerase chain reaction (PCR) was applied to determine the MyD88 and TRAF-6 gene expression and western blot was used to detect the MyD88 and TRAF-6 protein expression. The ALP activity in the SIN groups was lower than that in the control group, among which the 0.5 mM SIN group had the lowest ALP activity (P < 0.01). The rate of RA-FLS proliferation detected by CCK-8 assay in the 0.5-mM SIN group was lower than that in the control group (P < 0.01) and was the highest 4 days after SIN induction. Gene and protein expression of MyD88 and TRAF-6 were downregulated significantly in the 0.5-mM SIN group compared to that in the control group (P < 0.01). SIN effectively inhibited MyD88 and TRAF-6 expression in RA-FLS, which may be one of the important molecular mechanisms involved in RA treatment and prevention of cartilage and subchondral bone destruction.
Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Fibroblastos/efeitos dos fármacos , Morfinanos/farmacologia , Fator 88 de Diferenciação Mieloide/antagonistas & inibidores , Fator 6 Associado a Receptor de TNF/antagonistas & inibidores , Fosfatase Alcalina/antagonistas & inibidores , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Artrite Reumatoide/patologia , Artrite Reumatoide/cirurgia , Artroplastia , Proliferação de Células/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Regulação da Expressão Gênica , Humanos , Cápsula Articular/metabolismo , Cápsula Articular/patologia , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Cultura Primária de Células , Transdução de Sinais , Fator 6 Associado a Receptor de TNF/genética , Fator 6 Associado a Receptor de TNF/metabolismoRESUMO
Shoulder dislocation occurs in 1-2% of the population. Capsular deformation is a key factor in shoulder dislocation; however, little is known about capsule biology. We evaluated, for the first time in literature, the expression of COL1A1, COL1A2, COL3A1 and COL5A1 in the antero-inferior, antero-superior and posterior regions of the glenohumeral capsule of 31 patients with anterior shoulder instability and eight controls. The expression of collagen genes was evaluated by quantitative reverse transcription-PCR. The expression of COL1A1, COL3A1 and the ratio of COL1A1/COL1A2 were increased in all three portions of the capsule in patients compared to controls (p < 0.05). COL1A2 expression was upregulated in the antero-superior and posterior sites of the capsule of patients (p < 0.05). The ratio of COL1A2/COL3A1 expression was reduced in capsule antero-inferior and posterior sites of patients compared to controls (p < 0.05). In the capsule antero-inferior site of patients, the ratios of COL1A1/COL5A1, CO1A2/COL5A1 and COL3A1/COL5A1 expression were increased (p < 0.05). In patients, COL1A1/COL5A1 was also increased in the posterior site (p < 0.05). We found deregulated expression of collagen genes across the capsule of shoulder instability patients. These molecular alterations may lead to modifications of collagen fibril structure and impairment of the healing process, possibly with a role in capsular deformation.