RESUMO
OBJECTIVES: To investigate whether low-level laser therapy (LLLT) alters the expression and activity of MMP-2 and MMP-9 in the trigeminal ganglion (TG) during different stages of temporomandibular joint (TMJ) inflammation in rats. It also evaluated whether LLLT modifies mechanical allodynia and orofacial hyperalgesia. MATERIALS AND METHODS: Wistar rats (±250 g) were divided into groups that received saline (SAL) or complete Freund's adjuvant (CFA, 50 µl) in the TMJ, and that later underwent LLLT (20 J cm(-2) ) at their TMJ or not (groups SAL, SAL + LLLT, CFA, and CFA + LLLT). LLLT was applied on days 3, 5, 7, and 9 after SAL or CFA. Mechanical allodynia was evaluated on days 1, 3, 5, 7, and 10; orofacial hyperalgesia was assessed on day 10. Gelatin zymography and in situ zymography aided quantification of MMPs in the TG. RESULTS: Low-level laser therapy abolished the reduction in the mechanical orofacial threshold and the increase in orofacial rubbing during the orofacial formalin test induced by CFA. LLLT also decreased the CFA-induced rise in the levels of MMP-9 and MMP-2 as well as the gelatinolytic activity in the TG. CONCLUSION: Low-level laser therapy could constitute an adjuvant therapy to treat temporomandibular disorders and prevent inflammation-induced alterations in the levels of MMP-2 and MMP-9 and in the gelatinolytic activity in TGs.
Assuntos
Artrite Experimental/terapia , Colagenases/biossíntese , Terapia com Luz de Baixa Intensidade/métodos , Transtornos da Articulação Temporomandibular/enzimologia , Transtornos da Articulação Temporomandibular/terapia , Articulação Temporomandibular/inervação , Gânglio Trigeminal/enzimologia , Animais , Colagenases/metabolismo , Dor Facial/terapia , Adjuvante de Freund/farmacologia , Gelatina/metabolismo , Hiperalgesia/terapia , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Ratos , Ratos Wistar , Cloreto de Sódio/administração & dosagem , Articulação Temporomandibular/efeitos dos fármacos , Articulação Temporomandibular/cirurgia , Transtornos da Articulação Temporomandibular/patologia , Gânglio Trigeminal/metabolismo , Gânglio Trigeminal/patologiaRESUMO
BACKGROUND AND OBJECTIVE: Although chronic periodontitis (CP) is a multifactorial condition, few studies have investigated the potential association of gene variants with the outcome of periodontal therapy. In a previous study, we reported that variants in the interleukin-8 (IL8) gene were associated with CP in a Brazilian population. The aim of this nonrandomized study was to investigate whether genetic susceptibility to CP, conferred by the presence of the IL8 ATC/TTC haplotype, influences the clinical outcomes of nonsurgical periodontal therapy and the IL-8 protein levels in the gingival crevicular fluid. MATERIAL AND METHODS: Forty-one individuals were grouped according to the presence (susceptible to CP; n = 21) or absence (not susceptible to CP; n = 20) of the IL8 ATC/TTC haplotype. These individuals received nonsurgical periodontal therapy from one periodontist, who was blinded to the genetic status of each patient, and follow up continued for 45 d. The clinical parameters and gingival crevicular fluid samples were collected at baseline and on day 45. The IL-8 levels were determined by an ELISA. The data were subjected to the Mann-Whitney U-test, Wilcoxon and Spearman tests and to multiple logistic-regression analysis. RESULTS: No significant differences between patients with or without the IL8 ATC/TTC haplotype were found for the outcome of nonsurgical periodontal therapy and IL-8 levels. The multiple logistic-regression analysis did not show a statistically significant association between the IL8 haplotype and the variables studied. CONCLUSION: In this longitudinal clinical study, we observed that neither the outcome of nonsurgical periodontal therapy nor the IL-8 levels were influenced by the IL8 ATC/TTC CP-susceptibility haplotype. Additional studies of CP patients from other ethnic populations are necessary to confirm these results.
Assuntos
Adenina , Periodontite Crônica/terapia , Citosina , Haplótipos/genética , Interleucina-8/genética , Timina , Adulto , Periodontite Crônica/genética , Índice de Placa Dentária , Feminino , Seguimentos , Predisposição Genética para Doença/genética , Líquido do Sulco Gengival/química , Líquido do Sulco Gengival/imunologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Perda da Inserção Periodontal/terapia , Índice Periodontal , Bolsa Periodontal/terapia , Método Simples-Cego , Resultado do TratamentoRESUMO
Orofacial pain is a prevalent symptom in modern society. Some musculoskeletal orofacial pain is caused by temporomandibular disorders (TMDs). This condition has a multi-factorial etiology, including emotional factors and alteration of the masticator muscle and temporomandibular joints (TMJs). TMJ inflammation is considered to be a cause of pain in patients with TMD. Extracellular proteolytic enzymes, specifically the matrix metalloproteinases (MMPs), have been shown to modulate inflammation and pain. The purpose of this investigation was to determine whether the expression and level of gelatinolytic activity of MMP-2 and MMP-9 in the trigeminal ganglion are altered during different stages of temporomandibular inflammation, as determined by gelatin zymography. This study also evaluated whether mechanical allodynia and orofacial hyperalgesia, induced by the injection of complete Freund's adjuvant into the TMJ capsule, were altered by an MMP inhibitor (doxycycline, DOX). TMJ inflammation was measured by plasma extravasation in the periarticular tissue (Evans blue test) and infiltration of polymorphonuclear neutrophils into the synovial fluid (myeloperoxidase enzyme quantification). MMP expression in the trigeminal ganglion was shown to vary during the phases of the inflammatory process. MMP-9 regulated the early phase and MMP-2 participated in the late phase of this process. Furthermore, increases in plasma extravasation in periarticular tissue and myeloperoxidase activity in the joint tissue, which occurred throughout the inflammation process, were diminished by treatment with DOX, a nonspecific MMP inhibitor. Additionally, the increases of mechanical allodynia and orofacial hyperalgesia were attenuated by the same treatment.
RESUMO
Orofacial pain is a prevalent symptom in modern society. Some musculoskeletal orofacial pain is caused by temporomandibular disorders (TMDs). This condition has a multi-factorial etiology, including emotional factors and alteration of the masticator muscle and temporomandibular joints (TMJs). TMJ inflammation is considered to be a cause of pain in patients with TMD. Extracellular proteolytic enzymes, specifically the matrix metalloproteinases (MMPs), have been shown to modulate inflammation and pain. The purpose of this investigation was to determine whether the expression and level of gelatinolytic activity of MMP-2 and MMP-9 in the trigeminal ganglion are altered during different stages of temporomandibular inflammation, as determined by gelatin zymography. This study also evaluated whether mechanical allodynia and orofacial hyperalgesia, induced by the injection of complete Freund's adjuvant into the TMJ capsule, were altered by an MMP inhibitor (doxycycline, DOX). TMJ inflammation was measured by plasma extravasation in the periarticular tissue (Evans blue test) and infiltration of polymorphonuclear neutrophils into the synovial fluid (myeloperoxidase enzyme quantification). MMP expression in the trigeminal ganglion was shown to vary during the phases of the inflammatory process. MMP-9 regulated the early phase and MMP-2 participated in the late phase of this process. Furthermore, increases in plasma extravasation in periarticular tissue and myeloperoxidase activity in the joint tissue, which occurred throughout the inflammation process, were diminished by treatment with DOX, a nonspecific MMP inhibitor. Additionally, the increases of mechanical allodynia and orofacial hyperalgesia were attenuated by the same treatment.
RESUMO
Like fluoride, lead (Pb) accumulates on the enamel surface pre-eruptively, but it is not yet known whether it also deposits on enamel while dental caries is developing. This study evaluates Pb distribution in bovine enamel slabs submitted to a pH-cycling regimen simulating the caries process. The slabs were subjected to 8 cycles of de- and remineralizing conditions, and Pb (as acetate salt) was added to the de- and remineralized solutions at concentrations of 30 µg/l (experimental group, E1) and 300 µg/l (experimental group, E2). The control group (C) consisted of solutions to which Pb was not added. After the pH cycling, 100-µm sections of the slabs were analyzed by polarizing microscopy, to observe the extent of caries-like lesions, and these sections were used for Pb estimation by Synchrotron radiation X-ray microfluorescence. Caries lesions were observed along all superficial enamel surfaces to an extent of 120 µm. A Pb concentration gradient was observed in enamel, which decreased toward dentine. The highest Pb signals were observed for group E2, and the differences were statistically significant at enamel depths of 0 (C vs. E2; p = 0.029) and 50 µm (C vs. E2 and E1 vs. E2; p = 0.029). In conclusion, this study suggests that if Pb is present in the oral environment, it may deposit in enamel during the caries process.
Assuntos
Cárie Dentária/metabolismo , Esmalte Dentário/metabolismo , Chumbo/farmacocinética , Remineralização Dentária , Animais , Bovinos , Cárie Dentária/patologia , Esmalte Dentário/patologia , Dentina/metabolismo , Dentina/patologia , Concentração de Íons de Hidrogênio , Microscopia de Polarização , Microscopia de Vídeo , Compostos Organometálicos/farmacocinética , Distribuição Aleatória , Espectrometria por Raios X , Temperatura , Fatores de TempoRESUMO
BACKGROUND AND PURPOSE: Mounting evidence implicates matrix metalloproteinase (MMP) in the vascular dysfunction and remodelling associated with hypertension. We tested the hypothesis that treatment with pyrrolidine dithiocarbamate (PDTC), which interferes with NF-κB-induced MMPs gene transcription, could exert antihypertensive effects, prevent MMP-2 and MMP-9 up-regulation, and protect against the functional alterations and vascular remodelling of two-kidney, one clip (2K1C) hypertension. EXPERIMENTAL APPROACH: Sham-operated or hypertensive rats were treated with vehicle or PDTC (100 mg·Kg(-1) ·day(-1)) by gavage for 8 weeks. Systolic blood pressure (SBP) was monitored weekly. Aortic rings were isolated to assess endothelium-dependent relaxations. Quantitative morphometry of structural alterations of the aortic wall was carried out in haematoxylin/eosin sections. Formation of vascular reactive oxygen species (ROS), and inducible (i) NOS and phosphorylated-p65 NF-κB subunit expression were measured in the aortas. MMP-2 and MMP-9 aortic levels and gelatinolytic activity were determined by gelatin and in situ zymography and by immunofluorescence. KEY RESULTS: Treatment with PDTC attenuated the increases in SBP and prevented the endothelial dysfunction associated with 2K1C hypertension. Moreover, PDTC reversed the vascular aortic remodelling, the increases in aortic ROS levels and in iNOS and phosphorylated-p65 NF-κB expression found in 2K1C rats. These effects were associated with attenuation of 2K1C up-regulation of aortic MMP-2 and MMP-9 levels and gelatinolytic activity. CONCLUSION AND IMPLICATIONS: These findings suggest that PDTC down-regulates vascular MMPs and ameliorates vascular dysfunction and remodelling in renovascular hypertension, thus providing evidence supporting the suggestion that PDTC is probably a good candidate to be used to treat hypertension.
Assuntos
Anti-Hipertensivos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Hipertensão Renal/tratamento farmacológico , Metaloproteases/antagonistas & inibidores , Pirrolidinas/farmacologia , Tiocarbamatos/farmacologia , Animais , Aorta/efeitos dos fármacos , Aorta/fisiologia , Hipertensão Renal/complicações , Hipertrofia/tratamento farmacológico , Masculino , Metaloproteases/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Ratos WistarRESUMO
AIM: Our aim was to test the hypothesis that co-exposure to lead and fluoride alter the severity of enamel fluorosis. MATERIALS AND METHODS: Wistar rats were allocated in four groups: control, and 3 groups that received water containing 100 ppm of fluoride (F), 30 ppm of lead (Pb), or 100 ppm of F and 30 ppm of Pb (F+Pb) from the beginning of gestation. Enamel analysis and F and Pb determinations in enamel, dentine, and bone were performed in 81-day-old animals. Fluorosis was quantified using a new fluorosis index based on the identification of incisor enamel defects (white bands and white islets, representing hypomineralization, and cavities) weighted according to their severity and quantity. Hypomineralization was validated histopathologically by polarizing microscopy and microradiography. Scores were given by two blinded calibrated examiners (intra and interexaminer kappa values were 0.8 and 0.86, respectively). RESULTS: The control and the Pb groups presented normal enamel. The F+Pb group presented more severe enamel defects compared with the F group (P<0.0001). CONCLUSIONS: This study shows that lead exacerbates dental fluorosis in rodents, suggesting that co-exposure to lead may affect the degree of fluorosis.
Assuntos
Cariostáticos/efeitos adversos , Exposição Ambiental , Fluoretos/efeitos adversos , Fluorose Dentária/etiologia , Chumbo/efeitos adversos , Animais , Cariostáticos/análise , Cárie Dentária/induzido quimicamente , Cárie Dentária/patologia , Esmalte Dentário/química , Dentina/química , Sinergismo Farmacológico , Feminino , Fêmur/química , Fluoretos/análise , Fluorose Dentária/classificação , Fluorose Dentária/patologia , Incisivo/química , Chumbo/análise , Chumbo/sangue , Masculino , Microrradiografia , Microscopia de Polarização , Fósforo/análise , Distribuição Aleatória , Ratos , Ratos Wistar , Calcificação de Dente/efeitos dos fármacos , Desmineralização do Dente/induzido quimicamente , Desmineralização do Dente/classificação , Desmineralização do Dente/patologia , Abastecimento de Água/análiseRESUMO
BACKGROUND AND PURPOSE: Increased oxidative stress and up-regulation of matrix metalloproteinases (MMPs) may cause structural and functional vascular changes in renovascular hypertension. We examined whether treatment with spironolactone (SPRL), hydrochlorothiazide (HCTZ) or both drugs together modified hypertension-induced changes in arterial blood pressure, aortic remodelling, vascular reactivity, oxidative stress and MMP levels and activity, in a model of renovascular hypertension. EXPERIMENTAL APPROACH: We used the two-kidney,one-clip (2K1C) model of hypertension in Wistar rats. Sham-operated or hypertensive rats were treated with vehicle, SPRL (25 mg.kg(-1).day(-1)), HCTZ (20 mg.kg(-1).day(-1)) or a combination for 8 weeks. Systolic blood pressure was monitored weekly. Aortic rings were isolated to assess endothelium-dependent and -independent relaxations. Morphometry of the vascular wall was carried out in sections of aorta. Aortic NADPH oxidase activity and superoxide production were evaluated. Formation of reactive oxygen species was measured in plasma as thiobarbituric acid-reactive substances. Aortic MMP-2 levels and activity were determined by gelatin and in situ zymography, fluorimetry and immunohistochemistry. KEY RESULTS: Treatment with SPRL, HCTZ or the combination attenuated 2K1C-induced hypertension, and reversed the endothelial dysfunction in 2K1C rats. Both drugs or the combination reversed vascular aortic remodelling induced by hypertension, attenuated hypertension-induced increases in oxidative stress and reduced MMP-2 levels and activity. CONCLUSIONS AND IMPLICATIONS: SPRL or HCTZ, alone or combined, exerted antioxidant effects, and decreased renovascular hypertension-induced MMP-2 up-regulation, thus improving the vascular dysfunction and remodelling found in this model of hypertension.
Assuntos
Antioxidantes/farmacologia , Hidroclorotiazida/farmacologia , Hipertensão Renovascular/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Espironolactona/farmacologia , Animais , Antioxidantes/uso terapêutico , Aorta/efeitos dos fármacos , Aorta/enzimologia , Aorta/fisiopatologia , Pressão Sanguínea/efeitos dos fármacos , Quimioterapia Combinada , Hidroclorotiazida/uso terapêutico , Hipertensão Renovascular/tratamento farmacológico , Hipertensão Renovascular/fisiopatologia , Técnicas In Vitro , Peróxidos Lipídicos/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/fisiopatologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo , Espironolactona/uso terapêutico , Vasodilatação/efeitos dos fármacosRESUMO
We examined whether two functional polymorphisms (g.-1562C>T and g.-90(CA)14-24) in the matrix metalloproteinase (MMP)-9 gene or MMP-9 haplotypes affect the circulating levels of pro-MMP-9 and pro-MMP-9/TIMP-1 (tissue inhibitor of metalloproteinase-1) ratios in AIDS patients, and modulate alterations in these biomarkers after highly active antiretroviral therapy (HAART). We studied 82 patients commencing HAART. Higher pro-MMP-9 concentrations and pro-MMP-9/TIMP-1 ratios were found in CT/TT patients compared with CC patients. HAART decreased pro-MMP-9 levels and pro-MMP-9/TIMP-1 ratios in CT/TT patients, it did not modify pro-MMP-9 levels and it increased pro-MMP-9/TIMP-1 ratios in CC patients. The g.-90(CA)14-24 polymorphism, however, produced no significant effects. Moreover, we found no significant differences in HAART-induced changes in plasma pro-MMP-9, TIMP-1 and pro-MMP-9/TIMP-1 ratios when different MMP-9 haplotypes were compared. These findings suggest that the g.-1562C>T polymorphism affects pro-MMP-9 levels in patients with AIDS and modulates the alterations in pro-MMP-9 levels caused by HAART, thus possibly affecting the risk of cardiovascular complications.
Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Terapia Antirretroviral de Alta Atividade , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Doenças Cardiovasculares/induzido quimicamente , Precursores Enzimáticos , Frequência do Gene , Humanos , Metaloproteinase 9 da Matriz/sangue , Metaloproteinase 9 da Matriz/genética , Polimorfismo Genético , Inibidor Tecidual de Metaloproteinase-1/sangueRESUMO
The interaction between metal ions and the oral environment is a major subject matter in dental research. Matrix metalloproteinases (MMPs) have been implicated in several pathological and physiological processes such as, periodontal tissue destruction, root caries, dentin calcification and pulpal inflammation. The aim of this work was to test the effect of zinc released from zinc oxide-eugenol (ZOE) cements, on the activity of the major pulpal gelatinolytic MMPs. Pulpal explants were cultured overnight in Dulbecco's Modified Eagle Medium and the activity of secreted enzymes was analysed by gelatin zymography in buffer conditioned with diverse ZOE cements. Phenanthroline, a zinc chelator, was used to revert the inhibition of MMPs caused by zinc. The major gelatinolytic proteinases present in the conditioned media were characterized as MMP-2 and MMP-9 by immunoprecipitation. All ZOE cements inhibited MMPs activity, whereas phenanthroline could partially revert the inhibition caused by plain ZOE and Intermediate Restorative Material (IRM).