Atorvastatin Accelerates Alveolar Bone Loss in Type 1 Diabetic Rats Submitted to Periodontitis.

Periodontal bone loss is potentiated by diabetes. Despite the beneficial anti-inflammatory and antiresorptive effects of Atorvastatin (ATV) on periodontitis, it has been reported to increase the risk of diabetes, which may modify the course of periodontal disease. Therefore, this study aimed to evaluate the effect of ATV on alveolar bone in rats with periodontitis and diabetes. For this, 72 Wistar rats were divided into groups: Naïve (N) not submitted to any procedure; Experimental periodontitis (EP) group submitted to ligature-induced periodontitis; diabetes mellitus (DM), submitted to EP and receiving single dose of streptozotocin (60 mg/kg, i.p.) after 12 hours of fasting; and ATV DM, submitted to EP and DM and receiving orally 27 mg/kg of ATV, 30 minutes before ligature placement, and continued daily until the 11th day. Animals from EP and DM received saline solution 0.9% as placebo. Glycemic levels measured in all animals and then were euthanized. Maxillae were collected for macroscopic, micro-tomographic, and microscopic analyses. DM caused intense bone loss (60%), characterized by a reduction in trabecular thickness and bone volume. DM reduced osteoblasts, increasing osteoclast counts, and induced an inflammatory infiltrate in the periodontium. ATV was found ineffective in protecting bone in diabetic rats, exacerbating bone loss by 21%. Additionally, ATV significantly increased blood glucose levels. In summary, ATV did not prevent alveolar bone loss or modulate inflammation in DM animals undergoing EP. ATV also increased blood glucose levels in these animals. Therefore, the systemic use of ATV in uncontrolled diabetic conditions should be carefully evaluated.

Facial representation of paroxysmal hemicrania and associated temporomandibular disorder: a case report / Hemicrania paroxística com representação na face e associação com disfunção temporomandibular: relato de caso

ABSTRACT Paroxysmal Hemicrania is a trigeminal autonomic cephalalgia described as a severe and strictly unilateral pain, which occurs in paroxysms at orbital, supraorbital and/ or temporal region. A 45-year-old woman presented to an orofacial pain specialist reporting severe, burning, throbbing, strictly right-sided headache associated to ipsilateral autonomic symptoms and orofacial pain. The pain was perceived on the maxillary region followed by pain spread to the head. Interdisciplinary evaluation, along with absolute responsiveness to indomethacin and normal Brain Magnetic Resonance imaging, led to the diagnosis of primary Episodic paroxysmal hemicrania with facial representation and myofascial pain of masticatory muscles. Dentists should be aware of paroxysmal hemicrania with facial representation and the possibility of temporomandibular disorder coexistence, in order to avoid misdiagnosis and inadequate management. Paroxysmal hemicrania may be first perceived on the face and may be associated with interparoxysmal pain. In these cases, efficient anamnesis and clinical evaluation followed by interdisciplinary approach is needed.

RESUMO A Hemicrania Paroxística é uma cefalalgia autonômica trigeminal descrita como uma dor severa e estritamente unilateral, que ocorre em paroxismos na região orbital, supraorbital e/ou temporal. Uma mulher de 45 anos de idade apresentou-se a um especialista em dor orofacial, referindo uma cefaleia intensa, ardente, latejante, estritamente do lado direito, associada a sintomas autonómicos ipsilaterais e dor orofacial. A dor era sentida na região maxilar, seguida de dor que se estendia à cabeça. A avaliação interdisciplinar, aliada à resposta absoluta à indometacina e à normalidade em ressonância magnética cerebral, levou ao diagnóstico de hemicrania paroxística episódica primária com representação facial e dor miofascial dos músculos mastigatórios. Os médicos dentistas devem estar atentos à hemicrania paroxística com representação facial e à possibilidade de coexistência de Disfunção Temporomandibular, de modo a evitar diagnósticos incorretos e um tratamento inadequado. A hemicrania paroxística pode ser percebida inicialmente na face e pode estar associada à dor interparoxística. Nesses casos, é necessária uma anamnese e avaliação clínica eficientes, seguidas de abordagem interdisciplinar.

Biological and Molecular Docking Evaluation of a Benzylisothiocyanate Semisynthetic Derivative From Moringa oleifera in a Pre-clinical Study of Temporomandibular Joint Pain.

Objective: Moringa oleifera possesses multiple biological effects and the 4-[(4'-O-acetyl-α-L- rhamnosyloxy) benzyl] isothiocyanate accounts for them. Based on the original isothiocyanate molecule we obtained a semisynthetic derivative, named 4-[(2',3',4'-O-triacetyl-α-L-rhamnosyloxy) N-benzyl] hydrazine carbothioamide (MC-H) which was safe and effective in a temporomandibular joint (TMJ) inflammatory hypernociception in rats. Therefore, considering that there is still a gap in the knowledge concerning the mechanisms of action through which the MC-H effects are mediated, this study aimed to investigate the involvement of the adhesion molecules (ICAM-1, CD55), the pathways heme oxygenase-1 (HO-1) and NO/cGMP/PKG/K+ ATP, and the central opioid receptors in the efficacy of the MC-H in a pre-clinical study of TMJ pain. Methods: Molecular docking studies were performed to test the binding performance of MC-H against the ten targets of interest (ICAM-1, CD55, HO-1, iNOS, soluble cGMP, cGMP-dependent protein kinase (PKG), K+ ATP channel, mu (µ), kappa (κ), and delta (δ) opioid receptors). In in vivo studies, male Wistar rats were treated with MC-H 1 µg/kg before TMJ formalin injection and nociception was evaluated. Periarticular tissues were removed to assess ICAM-1 and CD55 protein levels by Western blotting. To investigate the role of HO-1 and NO/cGMP/PKG/K+ ATP pathways, the inhibitors ZnPP-IX, aminoguanidine, ODQ, KT5823, or glibenclamide were used. To study the involvement of opioid receptors, rats were pre-treated (15 min) with an intrathecal injection of non-selective inhibitor naloxone or with CTOP, naltrindole, or norbinaltorphimine. Results: All interactions presented acceptable binding energy values (below -6.0 kcal/mol) which suggest MC-H might strongly bind to its molecular targets. MC-H reduced the protein levels of ICAM-1 and CD55 in periarticular tissues. ZnPP-IX, naloxone, CTOP, and naltrindole reversed the antinociceptive effect of MC-H. Conclusion: MC-H demonstrated antinociceptive and anti-inflammatory effects peripherally by the activation of the HO-1 pathway, as well as through inhibition of the protein levels of adhesion molecules, and centrally by µ and δ opioid receptors.

Insights for temporomandibular disorders management: From psychosocial factors to genetics-A case report.

AIMS: This case report aimed to discuss the multifactorial etiology and also the management of temporomandibular disorders (TMD) by addressing important associated psychosocial and biological factors, emphasizing the interaction between these factors and a probable genetic predisposition. METHODS AND RESULTS: A 21-year-old female patient was evaluated according to Research Diagnostic Criteria for TMD and diagnosed with arthralgia, myofascial pain, disc displacement without reduction, and temporomandibular joint (TMJ) degenerative disease. TMJ alterations were confirmed through magnetic resonance imaging and cone-beam computed tomography. Pressure pain threshold of masticatory structures was evaluated using a pressure algometer. Sleep bruxism, poor sleep quality, migraine with aura, mild anxiety, and history of facial trauma were also identified through anamnesis and clinical examination. Following this, genetic analysis was performed to evaluate the presence of single nucleotide polymorphisms (SNPs) already associated with TMD: SNP COMT Val158 Met (rs4680), MMP1-1607 (rs1799750), and tumor necrosis factor alpha-308 (rs1800629), which were all present. A personalized treatment for TMD management was performed, and it included self-management programs, occlusal appliance therapy, pharmacotherapy, anxiety management, and stress control. An 8-year follow-up demonstrated long-term stabilization of TMJ degenerative disease. CONCLUSION: Genetic evaluation, added to anamnesis and clinical examination, could be useful for TMD prognosis and management.

Protective effect of Chresta martii extract on the zymosan-induced temporomandibular joint arthritis in rats.

OBJECTIVE: Chresta martii is broadly used by folk medicine due to its anti-inflammatory effects, but there is a lack of preclinical data on its pharmacological mechanisms. This study investigated the efficacy of Chresta martii ethanolic extract (CEE) in the zymosan-induced temporomandibular joint arthritis (TMJ) and evaluated the possible role of TNF-α, nitric oxide (NO), and heme oxygenase-1 (HO-1). METHODS: Male Wistar rats (160-220 g) were pre-treated with CEE (100, 200 or 400 mg/kg; v.o) 1 h before zymosan injection (2 mg; i.art). Mechanical hypernociception (g) was assessed 4 h later. The trigeminal ganglion was collected for TNF-α quantification (ELISA), total cell count and myeloperoxidase activity (MPO) were assayed in the synovial lavage 6 h after arthritis induction. Additionally, animals were pre-treated with L-NAME (30 mg/kg; i.p.) or ZnPP-IX (3 mg/kg, s.c.) to assess the involvement of NO and HO-1, respectively. RESULTS: CEE 400 mg/kg (v.o) increased (p < 0.05) hypernociception threshold, reduced the cell counts and MPO activity in the synovial lavage, as well as decreased TNF-α levels in the trigeminal ganglion. ZnPP-IX abolished the analgesic effect of CEE, but not L-NAME. CONCLUSION: The anti-inflammatory and antinociceptive effects of CEE depended on the HO-1 pathway integrity and TNF-α suppression.

Sulfated polysaccharide from the green marine algae Caulerpa racemosa reduces experimental pain in the rat temporomandibular joint.

Temporomandibular disorder is a clinical painful condition in the temporomandibular joint (TMJ) region. The purified sulfated polysaccharide from the green marine algae Caulerpa racemosa (Cr) has provided anti-inflammatory and antinociceptive activity. This study evaluated these effects on a TMJ hypernociception model. Wistar rats (180 - 250 g) were pre-treated (i.v.) with Cr at 0.01, 0.1, or 1 mg/kg or vehicle 30 min before formalin (1.5%/50 µL, i.art.), capsaicin (1.5%/20 µL, i.art.), or serotonin (225 µg/50 µL, i.art.) in the TMJ, and nociceptive behaviors were measured for 45 or 30 min upon inflammatory stimuli. Inflammatory parameters vascular permeability assay, TNF-α, and IL-1ß by ELISA, protein expression of adhesion molecules ICAM-1 and CD55 by Western blot were assessed. The involvement of heme oxygenase-1 (HO-1) and nitric oxide (NO) pathways were assessed by pharmacological inhibition. Cr (1 mg/kg) reduced nociceptive behavior, plasmatic extravasation, TNF-α, and IL-1ß levels, as well as ICAM-1 and CD55 expression in periarticular tissues. Cr antinociceptive effect was not prevented by aminoguanidine, but ZnPP-IX did reduce its antinociceptive effect. Therefore, Cr antinociceptive and anti-inflammatory effects in this experimental model of hypernociception depended on the HO-1 pathway integrity, as well as reducing peripheral inflammatory events, e.g., TNF-α and IL-1ß cytokines levels, ICAM-1 and CD55 expression.

Conhecimento dos agentes comunitários de saúde sobre as disfunções temporomandibulares no município de Sobral, Ceará / Knowledge of community health agents on temporomandibular dysfunctions in the city of Sobral, Ceará

Objetivo: verificar o conhecimento dos agentes comunitários de saúde (ACS) sobre as disfunções temporomandibulares (DTMs) no município de Sobral, Ceará. Materiais e Método: trata-se de uma pesquisa observacional transversal, quantitativa, realizada entre janeiro e março de 2014. Foram avaliados 158 ACS que responderam um questionário composto por 10 questões sociodemográficas e 16 perguntas relacionadas ao conhecimento sobre DTMs. A análise estatística foi realizada no Statistical Package for the Social Sciences (SPSS), versão 17.0, por meio dos testes Qui-Quadrado e Exato de Fisher, com significância de 5%. Resultados: observou-se que 73,4% dos ACS desconhecem as DTMs e 83,5% nunca receberam ensinamento sobre o tema. Dos ACS que tinham recebido ensinamento, 100% identificaram alguma possível causa de DTMs; dos que tinham ensino médio completo, 33,6% identificaram pelo menos um sintoma de DTMs. Conclusão: os ACS com maior grau de instrução e que receberam capacitação prévia são os que mais conhecem e, consequentemente, melhor identificam causas e consequências das DTMs, orientando o paciente adequadamente. Evidencia-se, portanto, o desconhecimento desses agentes sobre as DTMs, justificando-se a necessidade de realizar capacitações com esses indivíduos, para que tenham um maior conhecimento sobre o assunto e possam orientar corretamente a população. (AU)

Aim: the aim of the article is to verify the knowledge of the CHW on Temporomandibular Dysfunction (TMD) in the city of Sobral, Ceará. Materials and Methods: the present study is a cross-sectional, observational, quantitative study conducted between January and March 2014. We evaluated 158 CHW who answered a questionnaire composed of 10 questions about sociodemographic characteristics, and 16 questions related to their knowledge about TMD. Statistical analysis was performed in the Statistical Package for the Social Sciences (SPSS), version 17.0, using chi-square tests and Fisher's exact test, with significance of 5%. Results: it was observed that 73.4% of CHW were unaware of TMD and that 83.5% never received any teaching on the subject. Among the CHW who had received instruction, 100% identified some possible causes of TMD, and 33.6% identified at least one symptom of the disease. Conclusion: therefore, the more educated CHW s who received prior training are the ones who know the most and, consequently, better identify the causes and consequences of TMD by orienting the patient appropriately. Therefore, it is evident that the CHW does not know about the TMD, justifying the need to carry out training workshops with the CHW, so that they have a better knowledge about TMD and can guide the population correctly. (AU)

Immunohistochemical Evaluation of GLUT-3 and GLUT-4 in Oral Epithelial Dysplasia and Oral Squamous Cell Carcinoma

Objectives: To evaluate immunohistochemically the expression of GLUT-3 and GLUT-4 in oral epithelial dysplasia (OED) and the oral squamous cell carcinoma (OSCC) and assess possible involvement in the malignant transformation of oral lesions. Methods: Tissue samples of 15 cases of OSCC and 15 of OED were subjected to immunohistochemistry with anti-GLUT-3 and anti-GLUT-4 antibodies. Five fields of each case were analyzed, to provide percentages of positive cells at 400X magnification. Result: GLUT-3 and GLUT-4 were positive in 100% of the analyzed samples, the percentage immunolabeling for GLUT-3 ranging from 19% to 73% in the OED group and 10% to 89% in the OSCC group. Positive immunolabeling for GLUT-4 ranged from 15.2% to 79.9% in the OSCC group and 27.1% to 92.6% in the OED group. Statistical analysis with the Mann-Whitney test revealed that there was a higher expression of GLUT-4 in the OED group than in the OSCC group (p=0.04) without any significant difference in the GLUT-3 expression (p=0.852). Conclusion: GLUT-4 expression may indicate some role in oncogenic mechanisms which can determine a malignant phenotype. Thus, it is suggested that further studies on the role of GLUT-3 in oral carcinogenesis be conducted.

A lectin fraction from green seaweed Caulerpa cupressoides inhibits inflammatory nociception in the temporomandibular joint of rats dependent from peripheral mechanisms.

Temporomandibular disorders are the second most common cause of orofacial pain mediated by inflammatory compounds, which in many cases leads to chronic orofacial pain. This study assessed the antinociceptive and anti-inflammatory effects of a lectin from the green seaweed Caulerpa cupressoides (CcL) on hypernociception inflammatory in TMJ of rats and investigated the involvement of different mechanisms. Rats received i.v. CcL 30 min prior to injection of flogistic agentes or 0.9% saline into the left TMJ. Pretreatment with CcL (0. 1; 1 or 10 mg/kg) promoted a reduction (p < 0.05) of inflammatory hypernociception induced by 1.5% Formalin along with inhibition of inflammatory plasma extravasation, cytokines levels, ciclooxigenase-2, and intercellular adhesion molecule (ICAM-1). CcL was able to inhibit the nociceptive response induced by 1.5% Capsaicin, suggesting that CcL has an antinociceptive effect, acting directly on the primary nociceptive neurons. CcL also inhibited the nociceptive response induced by Carrageenan (100 µg/TMJ) or Serotonin (5-HT) (225 µg/TMJ). In conclusion, the results demonstrate that administration of CcL has a potential antinociceptive and anti-inflammatory effect, with a mechanism that is partially dependent on TNF-α, IL-1ß, COX-2 and ICAM-1 inhibition and independently from the cannabinoide and opioid system and NO/cGMP/PKG/K+ATP channel pathway.

The efficacy of a lectin from Abelmoschus Esculentus depends on central opioid receptor activation to reduce temporomandibular joint hypernociception in rats.

Abelmoschus esculentus is largely cultivated in Northeastern Brazil for medicinal purposes, e.g. inflammatory conditions. This study aimed to evaluate the efficacy of Abelmoschus esculentus lectin (AEL) in reducing formalin-induced temporomandibular joint inflammatory hypernociception in rats. The behavioral experiments were performed in male Wistar rats (180-240 g). Rats were pre-treated (i.v.) with AEL (0.001, 0.01 or 0.1 mg/kg) 30 min before formalin injection (i.art.). To analyze the possible effect of opioid pathways on AEL efficacy, animals were pre-treated with naloxone or CTOP (µ opioid receptor antagonist), naltrindole (δ opioid receptor antagonist) or nor-binaltorphimine (κ opioid receptor antagonist) (i.t.) 15 min before AEL administration followed by intra-TMJ injection of 1.5% formalin. Animals were monitored for a 45-min observation period. TMJ tissue, trigeminal ganglion, and subnucleus caudalis were collected for TNF-α dosage (ELISA). In addition, the vascular permeability was evaluated by Evans Blue extravasation. AEL significantly reduced formalin-induced TMJ inflammatory hypernociception and decreased Evans blue extravasation. It decreased TNF-α levels in the TMJ tissue, trigeminal ganglion, and subnucleus caudalis. AEL antinociceptive effects were not observed in the presence of naltrindole or nor-binaltorphimine, suggesting that AEL efficacy depends on TNF-α inhibition and the activation of δ and κ opioid receptors. AEL has provided prominent analgesic and anti-inflammatory effects in this pre-clinical model of TMJ, supporting its possible use as a pharmacological tool for the management of painful conditions.

Tocoyena sellowiana extract decreases bone loss in an experimental model of periodontitis in rats: Putative role for cyclooxygenase-2 and IL-1? inhibition.

Tocoyena sellowiana (Cham. & Schltdl.) K.Schum is one of the most important families of Brazilian medicinal plants. This study aimed to evaluate the effect of Tocoyena sellowiana (Cham. & Schltdl.) K.Schum ethanolic extract in a pre-clinical trial of periodontitis and to investigate possible mechanisms underlying such effects. Periodontitis was induced in Wistar rats by placing a nylon thread ligature around second upper left molars for 11 days. Rats received (per os) Tocoyena sellowiana (0.1, 1 or 10?mg?kg) or vehicle 1?h before ligature and daily until day 11. Macroscopic, histopathological, and COX-2 immunohistochemical analyses were performed to evaluate the periodontium. The gingival tissue was used to quantify the myeloperoxidase (MPO) activity and interleukin (IL)-1? levels by ELISA. Blood samples were collected to evaluate bone-specific alkaline phosphatase (BALP), the dosage of creatinine, aspartate and alanine transaminases. The liver, kidneys, spleen, and body mass variations were also evaluated. Tocoyena sellowiana decreased bone loss, reduced MPO, IL-1? levels as well as COX-2 immunostaining, and increased BALP activity. Moreover, Tocoyena sellowiana did not alter organs nor body weight. Tocoyena sellowiana reduced bone loss in rats and its efficacy was at least partially dependent upon both IL-1? and cyclooxygenase-2 inhibition.

Heme oxygenase-1/biliverdin/carbon monoxide pathway downregulates hypernociception in rats by a mechanism dependent on cGMP/ATP-sensitive K+ channels.

OBJECTIVE AND DESIGN: To investigate the role of heme oxygenase-1 (HO-1), carbon monoxide (CO), and biliverdin (BVD) in the zymosan-induced TMJ arthritis in rats. MATERIALS AND METHODS: Mechanical threshold was assessed before and 4 h after TMJ arthritis induction in rats. Cell influx, myeloperoxidase activity, and histological changes were measured in the TMJ lavages and tissues. Trigeminal ganglion and periarticular tissues were used for HO-1, TNF-α, and IL-1ß mRNA time course expression and immunohistochemical analyses. Hemin (0.1, 0.3, or 1 mg kg-1), DMDC (0.025, 0.25, or 2.5 µmol kg-1), biliverdin (1, 3, or 10 mg kg-1), or ZnPP-IX (1, 3 or 9 mg kg-1) were injected (s.c.) 60 min before zymosan. ODQ (12.5 µmol kg-1; s.c.) or glibenclamide (10 mg kg-1; i.p.) was administered 1 h and 30 min prior to DMDC (2.5 µmol kg-1; s.c), respectively. RESULTS: Hemin (1 mg kg-1), DMDC (2.5 µmol kg-1), and BVD (10 mg kg-1) reduced hypernociception and leukocyte migration, which ZnPP (3 mg kg-1) enhanced. The effects of DMDC were counteracted by ODQ and glibenclamide. The HO-1, TNF-α, and IL-1ß mRNA expression and immunolabelling increased. CONCLUSIONS: HO-1/BVD/CO pathway activation provides anti-nociceptive and anti-inflammatory effects on the zymosan-induced TMJ hypernociception in rats.

Antinociceptive, anti-inflammatory and toxicological evaluation of semi-synthetic molecules obtained from a benzyl-isothiocyanate isolated from Moringa oleifera Lam. in a temporomandibular joint inflammatory hypernociception model in rats.

Inflammation is a key component of many clinical conditions that affect the temporomandibular joint (TMJ) and Moringa oleifera Lam. has been used to treat inflammatory diseases. Here, we evaluated the toxicological effects on mice of a naturally-occurring isothiocyanate from M. oleifera and its seven analogue molecules. Further, the anti-nociceptive and anti-inflammatory effects on a rat model of TMJ inflammatory hypernociception were assessed. The systemic toxicological profile was determined in mice over a 14-day period: MC-1 1 µg/kg; MC-D1 1 µg/kg, MC-D3 100 µg/kg, MC-D6 1 µg/kg, MC-D7 1 µg/kg, MC-D8 1 µg/kg, MC-D9 10 µg/kg, and MC-H 1 µg/kg. The safest molecules were assayed for anti-nociceptive efficacy in the formalin (1.5%, 50 µL) and serotonin (255 mg) induced TMJ inflammatory hypernociception tests. The anti-inflammatory effect was evaluated through the vascular permeability assay using Evans blue. Further, the rota-rod test evaluated any motor impairment. Among the tested molecules, MC-D7, MC-D9, and MC-H were not toxic at the survival rate test, biochemical, and hystological analysis. They reduced the formalin-induced TMJ inflammatory hypernociception, but only MC-H decreased the serotonin-induced TMJ inflammation, suggesting an adrenergic receptor-dependent effect. They diminished the plasmatic extravasation, showing anti-inflammatory activity. At the rota-rod test, no difference was observed in comparison with control groups, reinforcing the hypothesis of anti-nociceptive effetc without motor impairment in animals. The analogues MC-D7, MC-D9, and MC-H were safe at the tested doses and efficient in reducing the formalin-induced TMJ hypernociception in rats. Our next steps include determining their mechanisms of anti-nociceptive action.

Strontium Ranelate Elevates Expression of Heme Oxygenase-1 and Decreases Alveolar Bone Loss in Rats.

OBJECTIVES: The purpose of this study was to determine the effects of strontium ranelate on ligature-induced periodontitis in rats and assess the putative involvement of heme oxygenase-1 (HO-1) pathway in these effects. MATERIAL AND METHODS: Male Wistar rats underwent nylon ligature placement around maxillary molars and were treated (v.o.) with strontium ranelate (20 or 100 mg/kg) for 7 days. After that, rats were euthanized and histomorphometric/histopathological analyses and RT-PCR for HO-1 expression were performed. RESULTS: Strontium ranelate (20 or 100 mg/kg) prevented bone resorption by 28% and 38%, respectively. Strontium ranelate treatment (100 mg/kg) up-regulated (P < 0.05) heme oxygenase-1 mRNA levels in the gingival tissues in comparison to control groups. CONCLUSIONS: Strontium ranelate prevented periodontal bone loss in experimental periodontitis in rats while heme oxygenase-1 mRNA levels increased after treatment.

Anti-inflammatory and anti-nociceptive effects of strontium ranelate on the zymosan-induced temporomandibular joint inflammatory hypernociception in rats depend on TNF-α inhibition.

BACKGROUND: Temporomandibular joint (TMJ) disorders show inflammatory components, heavily impacting on quality of life. Strontium ranelate has previously shown anti-inflammatory and antinociceptive effects on other experimental inflammatory pain models. Thus, we aim to investigate the strontium ranelate efficacy in reducing the zymosan-induced inflammatory hypernociception in the TMJ of rats by evaluating the TNF-α, IL-1ß, and hemeoxygenase-1 (HO-1) involvement. METHODS: Wistar rats were treated with strontium ranelate (0.5, 5 or 50 mg/kg, per os) 1 h before zymosan injection (iart). Mechanical threshold was assessed by Von Frey test and synovial lavage was collected for leukocyte counting and myeloperoxidase measurement, joint tissue and trigeminal ganglion were excised for histopathological analysis (H&E) and TNF-α/IL-1ß levels dosage (ELISA). Moreover, rats were pre-treated with ZnPP-IX (3 mg/kg, sc), a specific HO-1 inhibitor, before strontium ranelate administration (0.5 mg/kg, per os), and Evans Blue (5 mg/kg, iv) was administered to assess plasma extravasation. Pre-treatment with indomethacin (5 mg/kg, sc) was used as positive control while the sham group received 0.9% sterile saline (per os and iart). RESULTS: Strontium ranelate did not reduce leukocyte counting, myeloperoxidase activity, Evans Blue extravasation, IL-1ß levels, and TNF-α/IL-1ß immunolabeling; but it increased the nociceptive threshold and reduced TNF-α levels. Additionally, HO-1 inhibition did not change the strontium ranelate effects. CONCLUSION: Strontium ranelate may achieve its antinociceptive effects through the reduction of TNF-α levels in the trigeminal ganglion, but not suppressing IL-1ß expression nor inducing the HO-1 pathway.

Role of central opioid on the antinociceptive effect of sulfated polysaccharide from the red seaweed Solieria filiformis in induced temporomandibular joint pain.

This study aimed to investigate the effect of sulfated polysaccharide from red seaweed Solieria filiformis (Fraction F II) in the inflammatory hypernociception in the temporomandibular joint (TMJ) of rats. Male Wistar rats were pretreated (30min) with a subcutaneous injection (s.c.) of vehicle or FII (0.03, 0.3 or 3.0mg/kg) followed by intra-TMJ injection of 1.5% Formalin or 5-hydroxytryptamine (5-HT, 225µg/TMJ). In other set of experiments rats were pretreated (15min) with an intrathecal injection of the non-selective opioid receptors Naloxone, or µ-opioid receptor antagonist CTOP, or δ-opioid receptor Naltridole hydrochloride, or κ-opioid receptor antagonist Nor-Binaltorphimine (Nor-BNI) followed by injection of FII (s.c.). After 30min, the animals were treated with an intra-TMJ injection of 1.5% formalin. After TMJ treatment, behavioral nociception response was evaluated for a 45-min observation period, animals were terminally anesthetized and periarticular tissue, trigeminal ganglion and subnucleus caudalis (SC) were collected plasma extravasation and ELISA analysis. Pretreatment with F II significantly reduced formalin- and serotonin-induced TMJ nociception, inhibit the plasma extravasation and inflammatory cytokines release induced by 1.5% formalin in the TMJ. Pretreatment with intrathecal injection of Naloxone, CTOP, Naltridole or Nor-BNI blocked the antinociceptive effect of F II in the 1.5% formalin-induced TMJ nociception. In addition, F II was able to significantly increase the ß-endorphin release in the subnucleus caudalis. The results suggest that F II has a potential antinociceptive and anti-inflammatory effect in the TMJ mediated by activation of opioid receptors in the subnucleus caudalis and inhibition of the release of inflammatory mediators in the periarticular tissue.

Mechanisms involved in antinociception induced by a polysulfated fraction from seaweed Gracilaria cornea in the temporomandibular joint of rats.

Temporomandibular disorder is a common clinical condition involving pain in the temporomandibular joint (TMJ) region. This study assessed the antinociceptive effects of a polysulfated fraction from the red seaweed Gracilaria cornea (Gc-FI) on the formalin-induced TMJ hypernociception in rats and investigated the involvement of different mechanisms. Male Wistar rats were pretreated with injection (sc) of saline or Gc-FI 1h before intra- TMJ injection of formalin to evaluate the nociception. The results showed that pretreatment with Gc-FI significantly reduced formalin-induced nociceptive behavior. Moreover, the antinociceptive effect of the Gc-FI was blocked by naloxone (a non-selective opioid antagonist), suggesting the involvement of opioids selective receptors. Thus, the pretreatment with selective opioids receptors antagonists, reversed the antinociceptive effect of the Gc-FI in the TMJ. The Gc-FI antinociceptive effect depends on the nitric oxide/cyclic GMP/protein kinase G/ATP-sensitive potassium channel (NO/cGMP/PKG/K+ATP) pathway because it was prevented by pretreatment with inhibitors of nitric oxide synthase, guanylate cyclase enzyme, PKG and a K+ATP blocker. In addition, after inhibition with a specific heme oxygenase-1 (HO-1) inhibitor, the antinociceptive effect of the Gc-FI was not observed. Collectively, these data suggest that the antinociceptive effect induced by Gc-FI is mediated by µ/δ/κ-opioid receptors and by activation NO/cGMP/PKG/K+ATP channel pathway, besides of HO-1.

Occurrence and antimicrobial susceptibility of enteric rods and pseudomonads isolated from the dental prostheses biofilm.

OBJECTIVE:: To determine the occurrence and the in vitro antimicrobial susceptibility of enteric rods and pseudomonads from the denture biofilm of 52 subjects at the Center for Dental Specialties of Sobral/ Ceara, Brazil. MATERIAL AND METHODS:: Denture biofilm was collected and samples plated on MacConkey agar. The isolated bacterial colonies were identified using the BBL Crystal enteric/non-fermenter system. Antibiotic bacterial susceptibility was assessed by the disc diffusion method of amoxicillin, amoxicillin/clavulanic acid, doxycycline, tetracycline, tobramycin, imipenem, cefotaxime, and ciprofloxacin. The Minimum Inhibitory Concentration (MIC) of cefotaxime, tobramycin, doxycycline, imipenem, and ciprofloxacin was determined for 40 species by E-test. RESULTS:: 34 subjects (65.4%) harbored enteric rods in their prostheses. Klebsiella pneumoniae (26.5%), Escherichia coli (23.5%), and Enterobacter aerogenes (23.5%) were the most prevalent species. All organisms were susceptible to ciprofloxacin and most species were resistant to amoxicillin or amoxicillin/clavulanic acid, demonstrating variable sensitivity patterns to other antimicrobials. However, the MIC showed the emergence of strains with reduced sensitivity to ciprofloxacin (MIC90≥3 µg/ mL) and cefotaxime (MIC90≥2 µg/mL). CONCLUSION:: The findings show high prevalence of nosocomial diseases-related bacterial species and low susceptibility to antimicrobial drugs. Therefore, these results imply caution against the indiscriminate use of broad spectrum antibiotics in dental practice.

Occurrence and antimicrobial susceptibility of enteric rods and pseudomonads isolated from the dental prostheses biofilm

ABSTRACT Aspiration of oral bacteria leads to cardiac and respiratory infectious diseases and dentures can act as a reservoir for pathogenic microorganisms. Objective: To determine the occurrence and the in vitro antimicrobial susceptibility of enteric rods and pseudomonads from the denture biofilm of 52 subjects at the Center for Dental Specialties of Sobral/ Ceara, Brazil. Material and Methods: Denture biofilm was collected and samples plated on MacConkey agar. The isolated bacterial colonies were identified using the BBL Crystal enteric/non-fermenter system. Antibiotic bacterial susceptibility was assessed by the disc diffusion method of amoxicillin, amoxicillin/clavulanic acid, doxycycline, tetracycline, tobramycin, imipenem, cefotaxime, and ciprofloxacin. The Minimum Inhibitory Concentration (MIC) of cefotaxime, tobramycin, doxycycline, imipenem, and ciprofloxacin was determined for 40 species by E-test. Results: 34 subjects (65.4%) harbored enteric rods in their prostheses. Klebsiella pneumoniae (26.5%), Escherichia coli (23.5%), and Enterobacter aerogenes (23.5%) were the most prevalent species. All organisms were susceptible to ciprofloxacin and most species were resistant to amoxicillin or amoxicillin/clavulanic acid, demonstrating variable sensitivity patterns to other antimicrobials. However, the MIC showed the emergence of strains with reduced sensitivity to ciprofloxacin (MIC90≥3 μg/ mL) and cefotaxime (MIC90≥2 μg/mL). Conclusion: The findings show high prevalence of nosocomial diseases-related bacterial species and low susceptibility to antimicrobial drugs. Therefore, these results imply caution against the indiscriminate use of broad spectrum antibiotics in dental practice.

Analgesic and anti-inflammatory actions on bradykinin route of a polysulfated fraction from alga Ulva lactuca.

We investigated structural features of polysaccharides from Ulva lactuca and their effects on the classical models of nociception and inflammation. Crude extract was obtained by enzymatic digestion and isolated by ion exchange chromatography on DEAE-cellulose. The fraction with higher yield was used in the tests (SP-Ul). Swiss mice received SP-Ul (1, 3 or 9mg/kg; i.v.), 30min prior to injection of 0.8%-acetic acid or 1%-formalin or prior to a thermal stimulus. At same doses, SP-Ul was tested on Wistar rats on paw edema elicited by different irritants (carrageenan, dextran, bradykinin, histamine or serotonin). The results of infrared characterization indicated the presence of hydroxyl groups, sulfate, uronic acid and glycosidic linkages in all SP fractions spectrums. SP-Ul decreased significantly the antinociception in response to acetic acid or formalin (second phase), but not in the hot-plate test, suggesting that its analgesia occurs through a peripheral mechanism. SP-Ul did not reduce carrageenan-induced paw edema as supported by both histological and myeloperoxidase activity assessments. However, SP-Ul (1mg/kg; s.c.) reduced dextran-elicited edema, showing vascular anti-inflammatory effect, with bradykinin as major target because it did not reduce histamine- and serotonin-induced paw edemas. Therefore, SP-Ul acts on bradykinin pathway in its antinociceptive and anti-inflammatory responses.