nÃo hà / DisfunÃÃo temporomandibular (DTM) à um distÃrbio relacionado à funÃÃo do sistema mastigatÃrio que acomete as articulaÃÃes temporomandibulares (ATM), os mÃsculos mastigatÃrios e/ou estruturas associadas, embora os mecanismos envolvidos na inflamaÃÃo e na dor da ATM sejam pouco compreendidos. Apesar do grande interesse que hemeoxigenase-1 (HO-1) tem recebido nos Ãltimos anos e a forte evidÃncia dos seus efeitos citoprotetores e anti-inflamatÃrios, o papel da via HO-1/bilivedina (BVD)/monÃxido de carbono (CO) na dor e inflamaÃÃo da ATM ainda nÃo foi estudado. O objetivo deste estudo à estabelecer um modelo experimental de hipernocicepÃÃo articular e artrite na ATM de ratos induzida por zymosan (Zy), estudar a via HO-1/BVD/CO, seu mecanismo atravÃs do guanosina monofostato cÃclico (GMPc)/canal de K+ sensÃvel a ATP, e sua interligaÃÃo com os mediadores inflamatÃrios fator de necrose tumoral alfa (TNFα) e interleucina-1 beta (IL-1β). Foram utilizados ratos Wistar machos (160-220 g). Injetou-se 40 ÂL de salina ou Zy (0,25; 0,5; 1 ou 2 mg) na ATM esquerda dos animais para induÃÃo de artrite. Esses animais foram sacrificados entre a 3 h e 48 h. Os parÃmetros avaliados foram anÃlise do limiar de hipernocicepÃÃo articular, contagem do influxo celular no lavado sinovial, estudo da permeabilidade vascular pelo extravasamento de azul de Evans, atividade de mieloperoxidase (MPO) e anÃlise histopatolÃgica. Os animais foram prÃ-tratados com hemina (indutor de HO-1; 0,1, 0,3 ou 1 mg/kg), DMDC (doador de CO; 0,025, 0,25 ou 2,5 Âmol/kg), biliverdina (produto final da via; 1, 3 ou 10 mg/kg ), ZnPP IX (inibidor seletivo de HO-1; 1, 3 ou 9 mg/kg), ou com ODQ (12,5 Âmol/kg, s.c.), inibidor de guanilato cilase solÃvel, ou glibenclamida (10 mg/kg, i.p.), inibidor de canal de K+ sensÃvel a ATP, prÃvio ao DMDC 2,5 Âmol/kg. TambÃm estudou-se a expressÃo gÃnica de HO-1, TNFα e IL-1β no tecido mole da ATM e no gÃnglio trigeminal e identificaram-se esses mediadores por imunohistoquÃmica. Realizou-se dosagem sÃrica de bilirrubina e de IL-1β no lavado sinovial. Observamos que Zy (2 mg) causou hipernocicepÃÃo articular, aumento do influxo celular no lavado sinovial, do extravasamento de azul de Evans e da atividade de MPO tempo-dependente entre a 3 h e a 24 h. A anÃlise histopatolÃgica mostrou que Zy (2 mg) induziu infiltrado celular na membrana sinovial (MS), no tecido conjuntivo periarticular, no tecido muscular esquelÃtico e espessamento da MS na 6 h apÃs induÃÃo da artrite. A partir do 10 d observaram-se crescente infiltrado celular, constituÃdo de mononuclerares, espessamento e fibrose da MS. Estimuladores da via HO-1/BVD/CO reduziram todos os parÃmetros, e ZnPP IX, inibidor de HO-1, intensificou os parÃmetros. TambÃm comprovou-se o envolvimento de CO/GMPc/canal de K+ sensÃvel a ATP, pois ODQ e glibenclamida reverteram a aÃÃo do DMDC. Observou-se aumento da expressÃo gÃnica e da presenÃa de HO-1, TNFα e IL-1β na ATM e no gÃnglio trigeminal, sendo condrÃcitos, sinoviÃcitos e neutrÃfilos, na ATM, e corpo celular do neurÃnio aferente primÃrio e cÃlulas satÃlites da glia, no gÃnglio trigeminal, as cÃlulas que foram positivas para HO-1, TNFα e IL-1β. Bilirrubina sÃrica encontrou-se aumentada, e IL-1β foi detectada no lavado sinovial. Portanto, nossos resultados sugerem que o modelo experimental proposto à adequado ao estudo da hipernocicepÃÃo articular e da artrite na ATM, e que a via HO-1/BVD/CO/GMPc/canal de K+ sensÃvel a ATP participa da fisiopatologia do processo, sendo este o primeiro trabalho a estudar esta via na hipernocicepÃÃo articular na ATM. Ademais, o balanÃo entre a atividade de HO-1, TNFα e IL-1β sÃo importantes no desenvolvimento da dor facial e da inflamaÃÃo da ATM. / Temporomandibular disorders (TMDs) encompass a group of musculoskeletal and neuromuscular conditions that involve the temporomandibular joints (TMJs), the masticatory muscles, and all associated tissues, although the mechanisms involved in the TMJ inflammation and pain are not clear. Beyond the great interest of the hemeoxigenase-1 (HO-1) and the evidence of its citoprotector and antiinflammatory effects, the role of the pathway HO-1/bilivedin (BVD)/carbon monoxide (CO) in the TMJ inflammation and pain was not yet investigated.The purpose of the study is to propose an experimental model of articular hypernociception and TMJ arthritis induced by zymosan (Zy), to investigate the role of the HO-1/BVD/CO and its mechanisms through GMPc/ K+ channel ATP sensitive pathway on these events and to evaluate its relationship with TNFα and IL-1β in rats. Inflammation was induced by intra-articular injection of zymosan (0.25, 0.5, 1 or 2mg) or saline into left TMJ. Mechanical hypernociception, cell influx, vascular permeability, myeloperoxidase activity, and histological changes were measured in TMJ lavages or tissues at selected time points. Hemin (0.1, 0.3 or 1 mg/kg), DMDC (0.025, 0.25 or 2.5 Âmol/kg), Biliverdin (1, 3 or 10 mg/kg) or ZnPP (1, 3 or 9 mg/kg) was injected (s.c.) 60 min before zymosan. ODQ (12.5 Âmol/kg; s.c.) or Glibenclamide (10 mg/kg; i.p.) was administered 1 h and 30 min prior to DMDC (2.5 ÂMol/Kg; s.c). The gene expression for mRNA from HO-1, TNF-α and IL-1β in the TMJ tissues and the trigeminal ganglia, and the gene expression was studied at selected time points. The level of bilirrubin in plasma and the level of IL-1β in the synovial lavage were determined. Zymosan-induced TMJ arthritis caused a time-dependent leucocyte migration, plasma extravasation, mechanical hypernociception, and neutrophil accumulation between 4 and 24 h. Histopathological analysis of TMJ of Zy injected animals showed inflammatory cell infiltration in synovial membrane (SM), in conective periarticular tissue, in squeletic muscle tissue and thickness of SM in 6 h after TMJ arthritis. Initiating on the 10th day of TMJ arthritis, it was observed continuous leucocyte infiltration, composed mainly with mononuclear cells, thickness and fibrosis of SM. Hemin (1 mg/kg), DMDC (2.5 Âmol/kg) and Biliverdin (10 mg/kg) reduced facial mechanical hypernociception, leucocyte migration, and neutrophil accumulation, confirmed by histopathological analysis. ZnPP (3 mg/kg) potentiated all the parameters. ODQ and glibenclamide reverted the antinociceptive and antiinflammatory effects of the DMDC. It was also observed increased expression of mRNA for HO-1, TNF-α and IL-1β in the TMJ tissues and in the trigeminal ganglia, and it was identified, through imunohistochemistry reaction, that chondhrocytes, synoviocytes and neutrophils are the source of these proteins in the TMJ, and aferente neuron cell body and satellite glial cells are the source of these protein in the trigeminal ganglia. The level of bilirrubin was increased in the plasma, as well as IL-1β level in the synovial lavage. These results sugest that zymosan-induced TMJ arthritis is a reproducible model that may be used to assess both the mechanisms underlying TMJ pain and inflammation and the potential tools for therapies. Furthermore, HO-1/BVD/CO/GMPc/K+ channel ATP sensitive pathway participate in the physiopathological mechanisms of TMJ pain and inflammation, emphasizing that this is the first study to show this pathway on theTMJ articular hypernociception. Beyond, the balance between HO-1, TNFα and IL-1β activity is important on the development of the TMJ pain and inflammation.
| Identifer | oai:union.ndltd.org:IBICT/oai:www.teses.ufc.br:9449 |
| Date | 13 June 2012 |
| Creators | HellÃada Vasconcelos Chaves |
| Contributors | Gerly Anne de Castro Brito, Mirna Marques Bezerra, Karuza Maria Alves Pereira, Juliana Trindade Clemente Napimoga, Thiago Mattar Cunha |
| Publisher | Universidade Federal do CearÃ, Programa de PÃs-GraduaÃÃo em CiÃncias MÃdicas, UFC, BR |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/doctoralThesis |
| Format | application/pdf |
| Source | reponame:Biblioteca Digital de Teses e Dissertações da UFC, instname:Universidade Federal do Ceará, instacron:UFC |
| Rights | info:eu-repo/semantics/openAccess |
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