RESUMO
AIMS: To determine the involvement of tumor necrosis factor alpha (TNFα) signaling in the trigeminal ganglion (TG) in the mechanical hypersensitivity of the masseter muscle during temporomandibular joint (TMJ) inflammation. METHODS: A total of 55 male Sprague-Dawley rats were used. Following injection of Complete Freund's Adjuvant into the TMJ, the mechanical sensitivities of the masseter muscle and the overlying facial skin were measured. Satellite glial cell (SGC) activation and TNFα expression in the TG were investigated immunohistochemically, and the effects of their inhibition on the mechanical hypersensitivity of the masseter muscle were also examined. Student t test or two-way repeated-measures analysis of variance followed by Bonferroni multiple comparisons test were used for statistical analyses. P < .05 was considered to reflect statistical significance. RESULTS: Mechanical allodynia in the masseter muscle was induced without any inflammatory cell infiltration in the muscle after TMJ inflammation. SGC activation and an increased number of TNFα-immunoreactive cells were induced in the TG following TMJ inflammation. Intra-TG administration of an inhibitor of SGC activity or of TNFα-neutralizing antibody depressed both the increased number of TG cells encircled by activated SGCs and the mechanical hypersensitivity of the masseter following TMJ inflammation. CONCLUSION: These findings suggest that persistent masseter hypersensitivity associated with TMJ inflammation was mediated by SGC-TG neuron interactions via TNFα signaling in the TG.
Assuntos
Músculo Masseter/metabolismo , Transtornos da Articulação Temporomandibular/metabolismo , Gânglio Trigeminal/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Anticorpos Neutralizantes , Modelos Animais de Doenças , Adjuvante de Freund , Inflamação/induzido quimicamente , Masculino , Mecanotransdução Celular , Dor/etiologia , Estimulação Física , Ratos , Ratos Sprague-Dawley , Articulação Temporomandibular/metabolismo , Transtornos da Articulação Temporomandibular/induzido quimicamente , Fator de Necrose Tumoral alfa/antagonistas & inibidoresRESUMO
BACKGROUND: Bone morphogenetic proteins (BMPs) are members of the transforming growth factor-ß (TGF-ß) superfamily. Recently, BMP7 has been demonstrated to be produced by salivary glands and contribute to embryonic branching in mice. The BMP7 in saliva is thought to be delivered to the oral cavity and is expected to contact with stratified squamous epithelial cells which line the surface of oral mucosa. In this study, we attempted to investigate the effects of BMP7 on oral epithelial cells. METHODS: The expression of BMP receptors was examined by reverse transcriptase-polymerase chain reaction (RT-PCR). OSCCs were stimulated with human recombinant BMP7 (hrBMP7) and the phosphorylation status of Smad1/5/8 was examined by western blotting. For microarray analysis, Ca9-22 cells were stimulated with 100 ng/mL of hrBMP7 and total RNA was extracted and subjected to real-time PCR. The 5'-untranslated region (5'-UTR) of IL-17 F gene was cloned to pGL4-basic vector and used for luciferase assay. Ca9-22 cells were pre-incubated with DM3189, a specific inhibitor of Smad1/5/8, for inhibition assay. RESULTS: All isoforms of type I and type II BMP receptors were expressed in both Ca9-22 and HSC3 cells and BMP7 stimulation resulted in the phosphorylation of Smad1/5/8 in both cell lines. The microarray analysis revealed the induction of interleukin-17 F (IL-17 F), netrin G2 (NTNG2) and hyaluronan synthase 1 (HAS1). Luciferase assay using the 5'-UTR of the IL-17 F gene revealed transcriptional regulation. Induced IL-17 F production was further confirmed at the protein level by ELISA. Smad1/5/8 inhibitor pretreatment decreased IL-17 F expression levels in the cells.
Assuntos
Proteína Morfogenética Óssea 7/genética , Carcinoma de Células Escamosas/genética , Interleucina-17/genética , Neoplasias Bucais/genética , Proteínas Recombinantes/genética , Proteína Morfogenética Óssea 7/administração & dosagem , Proteína Morfogenética Óssea 7/metabolismo , Carcinoma de Células Escamosas/patologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Proteínas Ligadas por GPI/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Hialuronan Sintases/genética , Neoplasias Bucais/patologia , Netrinas/genética , Fosforilação , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/antagonistas & inibidores , Proteínas Smad/genética , Fator de Crescimento Transformador beta/genéticaRESUMO
Matrix metalloproteinases (MMPs) and tumor-associated macrophages (TAMs) play important roles in tumor growth. The present study investigated the expression levels of MMP2 and MMP9 in relation to the distribution of TAMs in the primary and metastatic regions of oral squamous cell carcinoma. Twenty-nine cases of oral squamous cell carcinoma (OSCC) with regional lymph node metastasis were selected from available documents in the archives of the Department of Pathology, Nihon University School of Dentistry. Four-micrometer-thick sections were prepared from the primary and metastatic regions. Each section was subjected to immunohistochemical staining using anti-MMP2, anti-MMP9, and anti-CD68 antibodies. The distribution and localization of MMPs and TAMs were compared between primary and metastatic regions. The expression levels of both MMPs were higher in the metastatic regions of lingual and gingival cancers. Statistically significant differences were observed in both T1 and T2 cases. In contrast to the higher expression of MMPs in metastatic regions, a higher number of TAMs were distributed in the primary regions. From these results, MMP expression levels and the numbers of TAMs were expected to have an inverse relationship between the primary and metastatic regions of OSCC. (J Oral Sci 58, 59-65, 2016).