Peripheral P2x7 Receptor-induced Mechanical Hyperalgesia Is Mediated By Bradykinin.

P2X7 receptors play an important role in inflammatory hyperalgesia, but the mechanisms involved in their hyperalgesic role are not completely understood. In this study, we hypothesized that P2X7 receptor activation induces mechanical hyperalgesia via the inflammatory mediators bradykinin, sympathomimetic amines, prostaglandin E2 (PGE2), and pro-inflammatory cytokines and via neutrophil migration in rats. We found that 2'(3')-O-(4-benzoylbenzoyl)adenosine 5'-triphosphate triethylammonium salt (BzATP), the most potent P2X7 receptor agonist available, induced a dose-dependent mechanical hyperalgesia that was blocked by the P2X7 receptor-selective antagonist A-438079 but unaffected by the P2X1,3,2/3 receptor antagonist TNP-ATP. These findings confirm that, although BzATP also acts at both P2X1 and P2X3 receptors, BzATP-induced hyperalgesia was mediated only by P2X7 receptor activation. Co-administration of selective antagonists of bradykinin B1 (Des-Arg(8)-Leu(9)-BK (DALBK)) or B2 receptors (bradyzide), β1 (atenolol) or β2 adrenoceptors (ICI 118,551), or local pre-treatment with the cyclooxygenase inhibitor indomethacin or the nonspecific selectin inhibitor fucoidan each significantly reduced BzATP-induced mechanical hyperalgesia in the rat hind paw. BzATP also induced the release of the pro-inflammatory cytokines tumor necrosis factor α (TNF-α), interleukin (IL)-1β, IL-6 and cytokine-induced neutrophil chemoattractant-1 (CINC-1), an effect that was significantly reduced by A-438079. Co-administration of DALBK or bradyzide with BzATP significantly reduced BzATP-induced IL-1β and CINC-1 release. These results indicate that peripheral P2X7 receptor activation induces mechanical hyperalgesia via inflammatory mediators, especially bradykinin, which may contribute to pro-inflammatory cytokine release. These pro-inflammatory cytokines in turn may mediate the contributions of PGE2, sympathomimetic amines and neutrophil migration to the mechanical hyperalgesia induced by local P2X7 receptor activation.

The Influence Of Altered Occlusion On Pro-inflammatory Cytokine Levels In The Tmj Synovial Tissues Of Rats.

The aim of this study was to evaluate whether altered occlusion affects both the condylar cartilage thickness and the cytokine levels of the TMJs of rats. Thirty adult-male rats (n=30) were randomly assigned to three experimental conditions: a control group that underwent sham operations with unaltered occlusion; an FPDM group that underwent functional posterior displacement of the mandible that was induced by an incisor guiding appliance; and an iOVD group in which the increased occlusal vertical dimension was induced in the molars. The rats were subjected to the FPDM or iOVD model for 14 days and then killed. Both the right and left TMJs were removed and randomly assigned to examination with staining or immunoassay techniques. Toluidine blue staining was used to measure the thicknesses of the four layers of the articular cartilage (i.e., the fibrous, proliferating, mature, and hypertrophic layers). ELISA assays were used to assess the concentrations of the pro-inflammatory cytokines IL-1α, IL-1β, IL-6, and tumour necrosis factor (TNF-α). The measurements of the articular cartilage layers and cytokine concentrations were analyzed with ANOVA and Tukey's tests and Kruskal-Wallis and Dunn tests, respectively (α=5%). The thickness of articular cartilage in the FPDM group (0.3±0.03mm) was significantly greater than those of the control (0.2±0.01mm) and iOVD (0.25±0.03mm) groups. No significant difference was observed between the control and iOVD groups. The four articular cartilage layers were thicker in the FPDM group than in the control and iOVD groups, and the latter two groups did not differ one from each other. Both the FPDM and iOVD groups exhibited higher cytokine levels than did the control (p<0.05) group. Compared to the FPDM group, the iOVD group exhibited significantly higher levels of IL-1β and TNF-α. Both models induced inflammation in the TMJ and caused significant structural changes in the TMJ and surrounding tissues.

Endocytosis Of Tight Junctions Caveolin Nitrosylation Dependent Is Improved By Cocoa Via Opioid Receptor On Rpe Cells In Diabetic Conditions.

Retinal pigment epithelium cells, along with tight junction (TJ) proteins, constitute the outer blood retinal barrier (BRB). Contradictory findings suggest a role for the outer BRB in the pathogenesis of diabetic retinopathy (DR). The aim of this study was to investigate whether the mechanisms involved in these alterations are sensitive to nitrosative stress, and if cocoa or epicatechin (EC) protects from this damage under diabetic (DM) milieu conditions. Cells of a human RPE line (ARPE-19) were exposed to high-glucose (HG) conditions for 24 hours in the presence or absence of cocoa powder containing 0.5% or 60.5% polyphenol (low-polyphenol cocoa [LPC] and high-polyphenol cocoa [HPC], respectively). Exposure to HG decreased claudin-1 and occludin TJ expressions and increased extracellular matrix accumulation (ECM), whereas levels of TNF-α and inducible nitric oxide synthase (iNOS) were upregulated, accompanied by increased nitric oxide levels. This nitrosative stress resulted in S-nitrosylation of caveolin-1 (CAV-1), which in turn increased CAV-1 traffic and its interactions with claudin-1 and occludin. This cascade was inhibited by treatment with HPC or EC through δ-opioid receptor (DOR) binding and stimulation, thereby decreasing TNF-α-induced iNOS upregulation and CAV-1 endocytosis. The TJ functions were restored, leading to prevention of paracellular permeability, restoration of resistance of the ARPE-19 monolayer, and decreased ECM accumulation. The detrimental effects on TJs in ARPE-19 cells exposed to DM milieu occur through a CAV-1 S-nitrosylation-dependent endocytosis mechanism. High-polyphenol cocoa or EC exerts protective effects through DOR stimulation.

Elevated Cetp Activity During Acute Phase Of Myocardial Infarction Is Independently Associated With Endothelial Dysfunction And Adverse Clinical Outcome.

Recent data suggests that cholesteryl ester transfer protein (CETP) activity may interact with acute stress conditions via inflammatory-oxidative response and thrombogenesis. We investigated this assumption in patients with ST-elevation myocardial infarction (STEMI). Consecutive patients with STEMI (n = 116) were enrolled <24-h of symptoms onset and were followed for 180 days. Plasma levels of C-reactive protein (CRP), interleukin-2 (IL-2), tumor necrosis factor (TNFα), 8-isoprostane, nitric oxide (NOx) and CETP activity were measured at enrollment (D1) and at fifth day (D5). Flow-mediated dilation (FMD) was assessed by ultrasound and coronary thrombus burden (CTB) was evaluated by angiography. Neither baseline nor the change of CETP activity from D1 to D5 was associated with CRP, IL-2, TNFα, 8-isoprostane levels or CTB. The rise in NOx from D1 to D5 was inferior [3.5(-1; 10) vs. 5.5(-1; 12); p < 0.001] and FMD was lower [5.9(5.5) vs. 9.6(6.6); p = 0.047] in patients with baseline CETP activity above the median value than in their counterparts. Oxidized HDL was measured by thiobarbituric acid reactive substances (TBARS) in isolated HDL particles and increased from D1 to D5, and remaining elevated at D30. The change in TBARS content in HDL was associated with CETP activity (r = 0.72; p = 0.014) and FMD (r = -0.61; p = 0.046). High CETP activity at admission was associated with the incidence of sudden death and recurrent MI at 30 days (OR 12.8; 95% CI 1.25-132; p = 0.032) and 180 days (OR 3.3; 95% CI 1.03-10.7; p = 0.044). An enhanced CETP activity during acute phase of STEMI is independently associated with endothelial dysfunction and adverse clinical outcome.

Effect Of Atorvastatin On Wound Healing In Rats.

Skin-wound healing is a complex and dynamic biological process involving inflammation, proliferation, and remodeling. Recent studies have shown that statins are new therapeutical options because of their actions, such as anti-inflammatory and antioxidant activity, on vasodilation, endothelial dysfunction and neoangiogenesis, which are independent of their lipid-lowering action. Our aim was to investigate the effect of atorvastatin on tissue repair after acute injury in healthy animals. Rats were divided into four groups: placebo-treated (P), topical atorvastatin-treated (AT), oral atorvastatin-treated (AO), topical and oral atorvastatin-treated (ATO). Under anesthesia, rats were wounded with an 8-mm punch in the dorsal region. Lesions were photographed on Days 0, 1, 3, 7, 10, 12, and 14 post-injury and samples taken on Days 1, 3, 7, and 14 for protein-expression analysis of insulin receptor substrate (IRS)-1, phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt), glycogen synthase kinase (GSK)-3, endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF), extracellular signal-regulated kinase (ERK), interleukin (IL)-10, IL-1β, IL-6, and tumor necrosis factor (TNF)-α. Upon macroscopic examination, we observed significant reductions of lesion areas in groups AT, AO, and ATO compared to the P group. Additionally, AT and AO groups showed increased expression of IRS-1, PI3K, Akt, GSK-3, and IL-10 on Days 1 and 3 when compared with the P group. All atorvastatin-treated groups showed higher expression of IRS-1, PI3K, Akt, GSK-3, IL-10, eNOS, VEGF, and ERK on Day 7. On Days 1, 3, and 7, all atorvastatin-treated groups showed lower expression of IL-6 and TNF-α when compared with the P group. We conclude that atorvastatin accelerated tissue repair of acute lesions in rats and modulated expressions of proteins and cytokines associated with cell-growth pathways.

Elevated Hypercoagulability Markers In Hemoglobin Sc Disease.

Hemoglobin SC disease is a very prevalent hemoglobinopathy, however very little is known specifically about this condition. There appears to be an increased risk of thromboembolic events in hemoglobin SC disease, but studies evaluating the hemostatic alterations are lacking. We describe a cross-sectional observational study evaluating coagulation activation markers in adult hemoglobin SC patients, in comparison with sickle cell anemia patients and healthy controls. A total of 56 hemoglobin SC and 39 sickle cell anemia patients were included in the study, all in steady state, and 27 healthy controls. None of the patients were in use of hydroxyurea. Hemoglobin SC patients presented a significantly up-regulated relative expression of tissue factor, as well as elevations in thrombin-antithrombin complex and D-dimer, in comparison to controls (p<0.01). Hemoglobin SC patients presented lower tissue factor expression, and thrombin-antithrombin complex and D-dimer levels when compared to sickle cell anemia patients (p<0.05). Endothelial activation (soluble thrombomodulin and soluble vascular cell adhesion molecule-1), and inflammation (tumor necrosis factor-alpha) markers were both significantly elevated in hemoglobin SC patients when compared to controls, being as high as the levels seen in sickle cell anemia. Overall, in hemoglobin SC patients, higher hemolytic activity and inflammation were associated with a more intense activation of coagulation, and hemostatic activation was associated with two very prevalent chronic complications seen in hemoglobin SC disease: retinopathy and osteonecrosis. In summary, our results demonstrate that hemoglobin SC patients present a hypercoagulable state, although this manifestation was not as intense as that seen in sickle cell anemia.

Increased Arterial Stiffness In Resistant Hypertension Is Associated With Inflammatory Biomarkers.

Increased levels of inflammatory biomarkers such as interleukin-6 (IL-6), 10 (IL-10), 1β (IL-1β), tumor necrosis factor-α (TNF-α) high-sensitivity C-reactive protein (hs-CRP) are associated with arterial stiffness in hypertension. Indeed, resistant hypertension (RHTN) leads to unfavorable prognosis attributed to poor blood pressure (BP) control and target organ damage. This study evaluated the potential impact of inflammatory biomarkers on arterial stiffness in RHTN. In this cross-sectional study, 32 RHTN, 20 mild hypertensive (HTN) and 20 normotensive (NT) patients were subjected to office BP and arterial stiffness measurements assessed by pulse wave velocity (PWV). Inflammatory biomarkers were measured in plasma samples. PWV was increased in RHTN compared with HTN and NT (p < 0.05). TNF-α levels were significantly higher in RHTN and HTN than NT patients. No differences in IL-6 levels were observed. RHTN patients had a higher frequency of subjects with increased levels of IL-10 and IL-1β compared with HTN and NT patients. Finally, IL-1β was independently associated with PWV (p < 0.001; R(2) = 0.5; β = 0.077). RHTN subjects have higher levels of inflammatory cytokines (TNF-α, IL-1β and IL-10) as well as increased arterial stiffness, and detectable IL-1β levels are associated arterial stiffness. These findings suggest that inflammation plays a possible role in the pathophysiology of RHTN.

Proinflammatory Activity Of Primarily Infected Endodontic Content Against Macrophages After Different Phases Of The Root Canal Therapy.

This study investigated the presence of target bacterial species and the levels of endotoxins in teeth with apical periodontitis. Levels of inflammatory mediators (interleukin [IL]-1β and tumor necrosis factor [TNF]-α) were determined after macrophage stimulation with endodontic content after different phases of endodontic therapy using different irrigants. Thirty primarily infected root canals were randomly assigned into 3 groups according to the irrigant used for root canal preparation (n = 10 per group): GI: 2.5% sodium hypochlorite, GII: 2% chlorhexidine gel, and GIII (control group): saline solution. Root canal samples were taken by using paper points before (s1) and after root canal instrumentation (s2), subsequently to 17% EDTA (s3), after 30 days of intracanal medication (Ca[OH]2 + saline solution) (s4), and before root canal obturation (s5). Polymerase chain reaction (16S recombinant DNA) and limulus amebocyte lysate assay were used for bacterial and endotoxin detection, respectively. Macrophages were stimulated with the root canal contents for IL-1β/TNF-α measurement using enzyme-linked immunosorbent assay. Porphyromonas gingivalis (17/30), Porphyromonas endodontalis (15/30), and Prevotella nigrescens (11/30) were the most prevalent bacterial species. At s1, endotoxins were detected in 100% of the root canals (median = 32.43 EU/mL). In parallel, substantial amounts of IL-1β and TNF-α were produced by endodontic content-stimulated macrophages. At s2, a significant reduction in endotoxin levels was observed in all groups, with GI presenting the greatest reduction (P < .05). After a root canal rinse with EDTA (s3), intracanal medication (s4), and before root canal obturation (s5), endotoxin levels reduced without differences between groups (P < .05). IL-1β and TNF-α release decreased proportionally to the levels of residual endotoxin (P < .05). Regardless of the use of sodium hypochlorite or CHX, the greatest endotoxin reduction occurs after chemomechanical preparation. Increasing steps of root canal therapy associated with intracanal medication enhances endotoxin reduction, leading to a progressively lower activation of proinflammatory cells such as macrophages.

Muscle Hyperalgesia Induced By Peripheral P2x3 Receptors Is Modulated By Inflammatory Mediators.

ATP, via activation of P2X3 receptors, has been highlighted as a key target in inflammatory hyperalgesia. Therefore, the aim of this study was to confirm whether the activation of P2X3 receptors in the gastrocnemius muscle of rats induces mechanical muscle hyperalgesia and, if so, to analyze the involvement of the classical inflammatory mediators (bradykinin, prostaglandins, sympathetic amines, pro-inflammatory cytokines and neutrophil migration) in this response. Intramuscular administration of the non-selective P2X3 receptor agonist α,β-meATP in the gastrocnemius muscle of rats induced mechanical muscle hyperalgesia, which, in turn, was prevented by the selective P2X3 and P2X2/3 receptors antagonist A-317491, the selective bradykinin B1-receptor antagonist Des-Arg9-[Leu8]-BK (DALBK), the cyclooxygenase inhibitor indomethacin, the β1- or β2-adrenoceptor antagonist atenolol and ICI 118,551, respectively. Also, the nonspecific selectin inhibitor fucoidan. α,β-meATP induced increases in the local concentration of the pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin 1β (IL-1β), which were reduced by bradykinin antagonist. Finally, α,β-meATP also induced neutrophil migration. Together, these findings suggest that α,β-meATP induced mechanical hyperalgesia in the gastrocnemius muscle of rats via activation of peripheral P2X3 receptors, which involves bradykinin, prostaglandins, sympathetic amines, pro-inflammatory cytokines release and neutrophil migration. It is also indicated that bradykinin is the key modulator of the mechanical muscle hyperalgesia induced by P2X3 receptors. Therefore, we suggest that P2X3 receptors are important targets to control muscle inflammatory pain.

Clinical Influence Of Different Intracanal Medications On Th1-type And Th2-type Cytokine Responses In Apical Periodontitis.

This clinical study assessed the influence of different intracanal medications on Th1-type and Th2-type cytokine responses in apical periodontitis and monitored the levels of bacteria from primarily infection during endodontic procedures. Thirty primarily infected teeth were randomly divided into 3 groups according to the medication selected: chlorhexidine (CHX), 2% CHX gel; Ca(OH)2/SSL, Ca(OH)2 + SSL; and Ca(OH)2/CHX, Ca(OH)2 + 2% CHX gel (all, n = 10). Bacterial sample was collected from root canals, and the interstitial fluid was sampled from lesions. Culture techniques were used to determine bacterial counts (colony-forming units/mL). Th1 (tumor necrosis factor-α, interferon-γ, and interleukin [IL]-2) and Th2 cytokines (IL-4, IL-5, and IL-13) were measured by enzyme-linked immunosorbent assay. All intracanal medication protocols were effective in reducing the bacterial load from root canals (all P < .05) and lowering the levels of Th1-type cytokines in apical lesions (all P < .05), with no differences between them (P > .05). Both Ca(OH)2 treatment protocols significantly increased the levels of Th2-type cytokines (P < .05), with no differences between them (P > .05). Thus, chlorhexidine medication showed the lowest effectiveness in increasing the levels of Th2-type cytokine. After treatment, regardless of the type of medication, the linear regression analysis indicated the down-regulation of Th2-type cytokines by Th1-type cytokines. All intracanal medication protocols were effective in reducing bacterial load and lowering the levels of Th1-type cytokines. Thus, the use of Ca(OH)2 medications contributed to the increase in the Th2-type cytokine response in apical periodontitis.

Comparative analysis of adverse events between infliximab and adalimumab in Crohn's disease management: a Brazilian single-centre experience

INTRODUCTION: Data is scarce regarding adverse events (AE) of biological therapy used in the management of Crohn's Disease (CD) among Brazilian patients. OBJECTIVES: To analyse AE prevalence and profile in patients with CD treated with Infliximab (IFX) or Adalimumab (ADA) and to verify whether there are differences between the two drugs. METHOD: Retrospective observational single-centre study of CD patients on biological therapy. Variables analysed: Demographic data, Montreal classification, biological agent administered, treatment duration, presence and type of AE and the need for treatment interruption. RESULTS: Forty-nine patients were analysed, 25 treated with ADA and 24 with IFX. The groups were homogeneous in relation to the variables studied. The average follow-up period for the group treated with ADA was 19.3 months and 21.8 months for the IFX group (p = 0.585). Overall, 40% (n = 10) of patients taking ADA had AE compared with 50% (n = 12) of IFX users (p = 0.571). There was a tendency towards higher incidence of cutaneous and infusion reactions in the IFX group and higher incidence of infections in the ADA treated group, although without significant difference. CONCLUSIONS: No difference was found in the AE prevalence and profile between ADA and IFX CD patients in the population studied.

Treinamento concorrente : efeito sobre marcadores inflamatórios sistêmicos e indicadores funcionais em homens de meia idade

Universidade Estadual de Campinas . Faculdade de Educação Física

Comparação da magnitude do dano muscular após ações excêntricas com diferentes velocidades em mulheres jovens e na pós-menopausa

Universidade Estadual de Campinas . Faculdade de Educação Física

Monitoramento de parâmetros imunológicos em atletas adolescentes de basquetebol durante e após a temporada esportiva= : Monitoring of immunological parameters in adolescent basketball athletes during and after a sports season

Universidade Estadual de Campinas . Faculdade de Educação Física

Increased Endothelial Cell-Leukocyte Interaction in Murine Schistosomiasis: Possible Priming of Endothelial Cells by the Disease

Background and Aims: Schistosomiasis is an intravascular parasitic disease associated with inflammation. Endothelial cells control leukocyte transmigration and vascular permeability being modulated by pro-inflammatory mediators. Recent data have shown that endothelial cells primed in vivo in the course of a disease keep the information in culture. Herein, we evaluated the impact of schistosomiasis on endothelial cell-regulated events in vivo and in vitro. Methodology and Principal Findings: The experimental groups consisted of Schistosoma mansoni-infected and age-matched control mice. In vivo infection caused a marked influx of leukocytes and an increased protein leakage in the peritoneal cavity, characterizing an inflamed vascular and cellular profile. In vitro leukocyte-mesenteric endothelial cell adhesion was higher in cultured cells from infected mice as compared to controls, either in the basal condition or after treatment with the pro-inflammatory cytokine tumor necrosis factor (TNF). Nitric oxide (NO) donation reduced leukocyte adhesion to endothelial cells from control and infected groups; however, in the later group the effect was more pronounced, probably due to a reduced NO production. Inhibition of control endothelial NO synthase (eNOS) increased leukocyte adhesion to a level similar to the one observed in the infected group. Besides, the adhesion of control leukocytes to endothelial cells from infected animals is similar to the result of infected animals, confirming that schistosomiasis alters endothelial cells function. Furthermore, NO production as well as the expression of eNOS were reduced in cultured endothelial cells from infected animals. On the other hand, the expression of its repressor protein, namely caveolin-1, was similar in both control and infected groups. Conclusion/Significance: Schistosomiasis increases vascular permeability and endothelial cell-leukocyte interaction in vivo and in vitro. These effects are partially explained by a reduced eNOS expression. In addition, our data show that the disease primes endothelial cells in vivo, which keep the acquired phenotype in culture.