RESUMO
BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a progressive and lethal disorder characterized by fibroproliferation and excessive accumulation of extracellular matrix in the lung. METHODS AND FINDINGS: Using oligonucleotide arrays, we identified osteopontin as one of the genes that significantly distinguishes IPF from normal lungs. Osteopontin was localized to alveolar epithelial cells in IPF lungs and was also significantly elevated in bronchoalveolar lavage from IPF patients. To study the fibrosis-relevant effects of osteopontin we stimulated primary human lung fibroblasts and alveolar epithelial cells (A549) with recombinant osteopontin. Osteopontin induced a significant increase of migration and proliferation in both fibroblasts and epithelial cells. Epithelial growth was inhibited by the pentapeptide Gly-Arg-Gly-Asp-Ser (GRGDS) and antibody to CD44, while fibroproliferation was inhibited by GRGDS and antibody to alphavbeta3 integrin. Fibroblast and epithelial cell migration were inhibited by GRGDS, anti-CD44, and anti-alphavbeta3. In fibroblasts, osteopontin up-regulated tissue inhibitor of metalloprotease-1 and type I collagen, and down-regulated matrix metalloprotease-1 (MMP-1) expression, while in A549 cells it caused up-regulation of MMP-7. In human IPF lungs, osteopontin colocalized with MMP-7 in alveolar epithelial cells, and application of weakest link statistical models to microarray data suggested a significant interaction between osteopontin and MMP-7. CONCLUSIONS: Our results provide a potential mechanism by which osteopontin secreted from the alveolar epithelium may exert a profibrotic effect in IPF lungs and highlight osteopontin as a potential target for therapeutic intervention in this incurable disease.
Assuntos
Pulmão/metabolismo , Fibrose Pulmonar/metabolismo , Sialoglicoproteínas/metabolismo , Líquido da Lavagem Broncoalveolar/química , Movimento Celular , Proliferação de Células , Células Cultivadas , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Matriz Extracelular/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 7 da Matriz/metabolismo , Pessoa de Meia-Idade , Dados de Sequência Molecular , Osteopontina , Fibrose Pulmonar/patologia , Proteínas Recombinantes/farmacologia , Sialoglicoproteínas/farmacologia , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Regulação para CimaRESUMO
Dentin is a reservoir of several potentially active molecules, and dentin sialoprotein (DSP) and dentin phosphoprotein (DPP) are the two major non-collagenous proteins. It has been established that dentin molecules are released as a consequence of osteoclast action during the resorption process. Along with osteoclasts, inflammatory cells seem to play an important role at sites of root resorption. Although the role of dentin molecules in dentinogenesis is well known, their role in pathological processes associated with dentin matrix dissolution is unclear. Recent studies have suggested that dentin components may function as chemotactic and activator signals for inflammatory cells at these sites. Herein we present evidence that demineralized dentin crude extract, DSP, and DPP induced doseand time-dependent neutrophil migration into the peritoneal cavity of mice and that this activity was inhibited by dexamethasone, but not by indomethacin or MK886. The blockade of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1) receptors inhibited neutrophil accumulation. The neutrophil migration was also diminished in the absence of the chemokines cytokine-induced neutrophil chemoattractant (KC) and macrophage inflammatory protein-2 (MIP-2), but not in the absence of macrophage inflammatory protein-1alpha (MIP-1alpha). These results demonstrate that dentin induces neutrophil migration via the synthesis of IL-1beta, TNF-alpha, and chemokines and they suggest that dentin matrix proteins may have an active role in inflammatory cell recruitment during pathological processes associated with dentin and bone matrix dissolution.
Assuntos
Quimiocinas/metabolismo , Dentina/química , Infiltração de Neutrófilos/efeitos dos fármacos , Fosfoproteínas/farmacologia , Sialoglicoproteínas/farmacologia , Extratos de Tecidos/farmacologia , Animais , Quimiocina CCL3 , Quimiocina CCL4 , Quimiocinas CXC/metabolismo , Quimiotaxia de Leucócito/efeitos dos fármacos , Dexametasona/farmacologia , Relação Dose-Resposta a Droga , Proteínas da Matriz Extracelular/farmacologia , Interleucina-1/metabolismo , Proteínas Inflamatórias de Macrófagos/deficiência , Proteínas Inflamatórias de Macrófagos/genética , Proteínas Inflamatórias de Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infiltração de Neutrófilos/fisiologia , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/deficiência , Fator de Necrose Tumoral alfa/genéticaRESUMO
1. The effect of IL-1ra on response to intraplantar (i.pl.) injection of LPS, carrageenin, bradykinin, TNFalpha, IL-1beta, IL-8, PGE(2) and dopamine was investigated in a model of mechanical hyperalgesia in rats. 2. IL-1ra inhibited hyperalgesic response to LPS, carrageenin, bradykinin, TNFalpha, and IL-1beta, but not responses to IL-8, PGE(2) and dopamine. 3. A sheep anti-rat IL-1ra serum potentiated response to LPS, carrageenin, bradykinin, TNFalpha and IL-1beta but not IL-8. 4. Carrageenin and LPS stimulated and production of immunoreactive TNFalpha, IL-1beta and IL-1ra in the skin of injected paws. 5. The inhibition by IL-1ra of the hyperalgesic response to carrageenin was not affected by antibodies neutralizing IL-4 and IL-10. 6. In mice, IL-1ra inhibited the nociceptive response to i.p. injection of acetic acid. 7. These data suggest that IL-1ra, released at sites of inflammation, limits inflammatory hyperalgesia. This effect is independent of (IL-1ra-induced) IL-4 and IL-10 and appears to be the result of antagonism by IL-1ra of IL-1beta-stimulated eicosanoid production.
Assuntos
Citocinas/farmacologia , Hiperalgesia/prevenção & controle , Inflamação/prevenção & controle , Sialoglicoproteínas/farmacologia , Ácido Acético/farmacologia , Animais , Anticorpos/imunologia , Anticorpos/farmacologia , Bradicinina/farmacologia , Carragenina/farmacologia , Citocinas/metabolismo , Dinoprostona/farmacologia , Dopamina/farmacologia , Relação Dose-Resposta a Droga , Membro Posterior , Hiperalgesia/metabolismo , Soros Imunes/farmacologia , Inflamação/metabolismo , Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-1/metabolismo , Interleucina-1/farmacologia , Interleucina-10/imunologia , Interleucina-4/imunologia , Interleucina-8/farmacologia , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Medição da Dor , Ratos , Ratos Wistar , Ovinos , Sialoglicoproteínas/imunologia , Sialoglicoproteínas/metabolismo , Pele/efeitos dos fármacos , Pele/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
The cytokine network participates in the modulation of the immune system. Furthermore, the formation of the cytokine-receptor complex, as well as the transcription, translation, secretion, or degradation of cytokines interfere with the functions of cytokines. Cytokine inhibitors include antagonists, soluble receptors, cytokine-binding proteins, and cytokines that block other cytokines. In autoimmune diseases, an abnormal production of proinflammatory cytokines, or a reduced inhibition of their actions, may lead to an imbalance. The main cytokine inhibitors include interleukin-1 receptor antagonist (IL-1ra), soluble IL-1 receptor (sIL-1R), soluble TNF-alpha receptors (soluble TNF-Rs), and certain cytokines, such as IL-4, TGF beta, and IL-10. The combination of cytokine inhibitors is a potential therapeutic approach in the treatment of immunoinflammatory diseases. The nonspecific effects of immunosuppressive drugs are improved by using inhibitors with more specific actions on the functions of proinflammatory cytokines.