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Objective: Supplementation with ω-3 polyunsaturated fatty acids (PUFAs) can positively contribute to neurologic development, modulating inflammatory responses, promoting homeostasis, and having a positive effect on animal behaviors associated with mental disorders. The aim of this study was to evaluate behavioral and biochemical effects of ω-3 fatty acid supplementation in an animal model for mental disorders by prenatal maternal exposure to lipopolysaccardies (LPS) from the maternal immune activation., Methods: Twelve pregnant Wistar rats were used. Each rat received 100 μg/kg of LPS or saline solution on gestational day (GD) 9.5. The offspring remained with mothers until weaning and from postnatal day (PND) 30 were supplemented with ω-3 PUFA or saline solution by gavage at a dose of 0.8 g/kg orally for 21 d. On PND 52, the animals underwent behavioral tests; then, they were sacrificed, and the brain structures were dissected and analyzed by levels: neuron-specific enolase (NSE), brain-derived neurotrophic factor, and transforming growth factor (TGF)-β., Result: Prenatal exposure to LPS significantly increased the episodes of stereotyped movements and decreased social interaction in the offspring (P = 0.009 and P = 0.001, respectively), after ω-3 PUFA supplementation these parameters reversed (P = 0.005 and P = 0.013, respectively). Significant changes also were identified in the biochemical analysis in NSE and TGF-β in the brain structures; these conditions were reversed after ω-3 PUFA supplementation., Conclusion: Supplementation with ω-3 PUFA reversed animal behaviors that often are observed in autism and other mental disorders in rats prenatally exposed to LPS, and also exerted neuroprotective effects in marker levels of neuronal damage and expression of TGF-β., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Low-level laser therapy (LLLT) controls bronchial hyperresponsiveness (BHR) associated with increased RhoA expression as well as pro-inflammatory mediators associated with NF-kB in acute lung inflammation. Herein, we explore if LLLT can reduce both BHR and Th2 cytokines in allergic asthma. Mice were studied for bronchial reactivity and lung inflammation after antigen challenge. BHR was measured through dose-response curves to acetylcholine. Some animals were pretreated with a RhoA inhibitor before the antigen. LLLT (660 nm, 30 mW and 5.4 J) was applied on the skin over the right upper bronchus and two irradiation protocols were used. Reduction of BHR post LLLT coincided with lower RhoA expression in bronchial muscle as well as reduction in eosinophils and eotaxin. LLLT also diminished ICAM expression and Th2 cytokines as well as signal transducer and activator of transduction 6 (STAT6) levels in lungs from challenged mice. Our results demonstrated that LLLT reduced BHR via RhoA and lessened allergic lung inflammation via STAT6., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Free radicals are known to play a major role in sepsis. Combined immuno-spin trapping and molecular magnetic resonance imaging (MRI) was used to detect in vivo and in situ levels of free radicals in murine septic encephalopathy after cecal ligation and puncture (CLP). DMPO (5,5-dimethyl pyrroline N-oxide) was injected over 6h after CLP, before administration of an anti-DMPO probe (anti-DMPO antibody bound to albumin-gadolinium-diethylene triamine pentaacetic acid-biotin MRI targeting contrast agent). In vitro assessment of the anti-DMPO probe in oxidatively stressed mouse astrocytes significantly decreased T1 relaxation (p < 0.0001) compared to controls. MRI detected the presence of anti-DMPO adducts via a substantial decrease in %T1 change within the hippocampus, striatum, occipital, and medial cortex brain regions (p < 0.01 for all) in septic animals compared to shams, which was sustained for over 60 min (p < 0.05 for all). Fluorescently labeled streptavidin was used to target the anti-DMPO probe biotin, which was elevated in septic brain, liver, and lungs compared to sham. Ex vivo DMPO adducts (qualitative) and oxidative products, including 4-hydroxynonenal and 3-nitrotyrosine (quantitative, p < 0.05 for both), were elevated in septic brains compared to shams. This is the first study that has reported on the detection of in vivo and in situ levels of free radicals in murine septic encephalopathy., (Copyright © 2013 Elsevier Inc. All rights reserved.)

We compared the effects of oleanolic acid (OA) vs. dexamethasone on lung mechanics and histology, inflammation, and apoptosis in lung and distal organs in experimental sepsis. Seventy-eight BALB/c mice were randomly divided into two groups. Sepsis was induced by cecal ligation and puncture, while the control group underwent sham surgery. 1h after surgery, all animals were further randomized to receive saline (SAL), OA and dexamethasone (DEXA) intraperitoneally. Both OA and DEXA improved lung mechanics and histology, which were associated with fewer lung neutrophils and less cell apoptosis in lung, liver, and kidney than SAL. However, only animals in the DEXA group had lower levels of interleukin (IL)-6 and KC (murine analog of IL-8) in bronchoalveolar lavage fluid than SAL animals. Conversely, OA was associated with lower inducible nitric oxide synthase expression and higher superoxide dismutase than DEXA. In the experimental sepsis model employed herein, OA and DEXA reduced lung damage and distal organ apoptosis through distinct anti-inflammatory mechanisms., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The possibility of free radical reactions occurring in biological processes led to the development and employment of novel methods and techniques focused on determining their existence and importance in normal and pathological conditions. For this reason the use of nitrones for spin trapping free radicals became widespread in the 1970s and 1980s, when surprisingly the first evidence of their potent biological properties was noted. Since then widespread exploration and demonstration of the potent biological properties of phenyl-tert-butylnitrone (PBN) and its derivatives took place in preclinical models of septic shock and then in experimental stroke. The most extensive commercial effort made to capitalize on the potent properties of the PBN-nitrones was for acute ischemic stroke. This occurred during 1993-2006, when the 2,4-disulfonylphenyl PBN derivative, called NXY-059 in the stroke studies, was shown to be safe in humans and was taken all the way through clinical phase 3 trials and then was deemed to be ineffective. As summarized in this review, because of its excellent human safety profile, 2,4-disulfonylphenyl PBN, now called OKN-007 in the cancer studies, was tested as an anti-cancer agent in several preclinical glioma models and shown to be very effective. Based on these studies this compound is now scheduled to enter into early clinical trials for astrocytoma/glioblastoma multiforme this year. The potential use of OKN-007 in combination with neurotropic compounds such as the lanthionine ketamine esters is discussed for glioblastoma multiforme as well as for various other indications leading to dementia, such as aging, septic shock, and malaria infections. There is much more research and development activity ongoing for various indications with the nitrones, alone or in combination with other active compounds, as briefly noted in this review., (Copyright © 2013 Elsevier Inc. All rights reserved.)

We tested the hypothesis that at the early phase of acute lung injury (ALI) the degree of endothelium injury may predict lung parenchyma remodelling. For this purpose, two models of extrapulmonary ALI induced by Escherichia coli lipopolysaccharide (ALI-LPS) or cecal ligation and puncture (ALI-CLP) were developed in mice. At day 1, these models had similar degrees of lung mechanical compromise, epithelial damage, and intraperitoneal inflammation, but endothelial lesion was greater in ALI-CLP. A time course analysis revealed, at day 7: ALI-CLP had higher degrees of epithelial lesion, denudation of basement membrane, endothelial damage, elastic and collagen fibre content, neutrophils in bronchoalveolar lavage fluid (BALF), peritoneal fluid and blood, levels of interleukin-6, KC (murine analogue of IL-8), and transforming growth factor-β in BALF. Conversely, the number of lung apoptotic cells was similar in both groups. In conclusion, the intensity of fibroelastogenesis was affected by endothelium injury in addition to the maintenance of epithelial damage and intraperitoneal inflammation., (Copyright 2010 Elsevier B.V. All rights reserved.)

Plasma activity of the platelet-activating factor acetylhydrolase (PAF-AH) plays an important role in inflammation and atherosclerotic process in chronic diseases. We aimed to evaluate the levels of PAF-AH activity and their association with the metabolic profile and chronic complications in patients with type 1 diabetes. The study included 118 outpatients (54 males) aged 27.1+/-11.3 years with disease duration of 12.3+/-8.5 years with (n=38) or without (n=80) diabetes complications and 96 control subjects (48 males) matched for age, gender, body mass index and smoking habits. The serum levels of PAF-AH activity were higher in patients either with or without chronic complications (16+/-5.3 and 14+/-5.4 nmol/(min mL), respectively) than in controls (13+/-5.1 nmol/(min mL), P=0.02). In the total population, PAF-AH activity was correlated with age, HDL-cholesterol, total cholesterol and LDL-cholesterol. In patients, PAF-AH activity was correlated with age, HbA1c, uric acid, HDL-cholesterol, cholesterol, LDL-cholesterol, cholesterol/HDL-cholesterol ratio and the LDL-cholesterol/HDL-cholesterol ratio. It is concluded that PAF-AH plasma activity could be a novel candidate for low-grade inflammatory marker in patients with type 1 diabetes.

Background and Objective: Low-level laser therapy (LLLT) is a known modulator of inflammatory process. Herein we studied the effect of 660 nm diode laser on mRNA levels of neutrophils anti-apoptotic factors in lipopolysaccharide (LPS)-induced lung inflammation. STUDY DESIGN/METHODOLOGY: Mice were divided into 8 groups (n=7 for each group) and irradiated with energy dosage of 7.5 J/cm(2). The Bcl-xL and A1 mRNA levels in neutrophils were evaluated by Real Time-PCR (RT-PCR). The animals were irradiated after exposure time of LPS., Results: LLLT and an inhibitor of NF-kappaB nuclear translocation (BMS 205820) attenuated the mRNA levels of Bcl-xL and A1 mRNA in lung neutrophils obtained from mice subjected to LPS-induced inflammation., Conclusion: LLLT reduced the levels of anti-apoptotic factors in LPS inflamed mice lung neutrophils by an action mechanism in which the NF-kappaB seems to be involved.

New therapeutic approaches for the treatment of allergic diseases can be aided by the development of agents capable of regulating eosinophilic leukocytes. Here, we evaluated the anti-allergic properties of a crude extract of the Brazilian bromeliaceae Nidularium procerum, focusing on its effects on allergic eosinophilia. By studying allergic pleurisy in actively sensitized C57Bl/6 mice, we observed that pretreatment with N. procerum (2 mg/kg; i.p.) reduced pleural eosinophil influx triggered by allergen challenge. N. procerum was also able to reduce lipid body numbers found within infiltrating eosinophils, indicating that N. procerum in vivo is able to affect both migration and activation of eosinophils. Consistently, pretreatment with N. procerum blocked pleural eosinophil influx triggered by PAF or eotaxin, key mediators of the development of allergic pleural eosinophilia. The effect of N. procerum was not restricted to eosinophils, since N. procerum also inhibited pleural neutrophil and mononuclear cell influx. Of note, N. procerum failed to alter the acute allergic reaction, characterized by mast cell degranulation, oedema, and cysteinyl leukotriene release. N. procerum also had direct effects on murine eosinophils, since it inhibited both PAF- and eotaxin-induced eosinophil chemotaxis on an in vitro chemotactic assay. Therefore, N. procerum may be a promising anti-allergic therapy, inasmuch as it presents potent anti-eosinophil activity.

As part of a program researching the synthesis and immunopharmacological evaluation of novel synthetic compounds, we have described the immune modulatory profile of the new achiral thalidomide analogue LASSBio-468 in the present work. This compound was planned as an N-substituted phthalimide derivate, structurally designed as a hybrid of thalidomide and aryl sulfonamides, which were previously described as tumor necrosis factor-alpha (TNF-alpha) and PDE4 inhibitors. LASSBio-468 was recently demonstrated to inhibit the TNF-alpha production induced by lipopolysaccharide (LPS), in vivo. Here, we investigated whether this compound would affect chronic inflammation processes associated with the production of this pro-inflammatory cytokine. Treatment with LASSBio-468 before a lethal dose injection of LPS in animals greatly inhibited endotoxic shock. This effect seems to be mediated by a specific down regulation of TNF-alpha and nitric oxide production, regulated mainly at the RNA level. In another model, histopathological analysis indicated that this compound also inhibited adjuvant-induced arthritis in rats. Taken together, our data demonstrated a potent anti-inflammatory effect of LASSBio-468, suggesting its use as a potential drug against chronic inflammatory diseases.

Neisseria meningitidis (N. meningitidis) is a serious bacterial pathogen that causes life-threatening invasive bacterial infections especially in children below 2 years of age, teenagers and young adults. We have investigated the protective potential of outer membrane vesicles (OMVs) and detoxified lipooligosaccharide (dLOS) obtained from Brazilian prevalent N. meningitidis serogroup B strains. Swiss mice were immunized with different combinations of OMV and dLOS from N. meningitidis serogroup B strains compared to a reference vaccine (VA-MENGOC-BC), Cuba). The OMVs + dLOS from Brazilian prevalent strains induced higher bactericidal antibody titers against homologous and heterologous target strains and stronger inhibition of thrombocytopenia as compared to the reference vaccine. When the challenge was performed with the B strain, all immunogens tested showed similar survival rates (80%) significantly higher than the control group. Bacterial clearance against the group B strain was comparable for animals immunized with the tested immunogen and the reference vaccine. Inclusion of dLOS from the B strain with the OMV, induced a similar clearance of C strain bacteria as compared to VA-MENGOC-BC. The immunogens, as well as the reference vaccine drastically inhibited increases in TNF-alpha and IL-6 plasma levels after challenge. In conclusion, the OMV/dLOS formulation obtained from Brazilian prevalent strains of N. meningitidis has a remarkable performance protecting mice against the lethal effects of meningococcal challenge showing a good potential as a vaccine and should be considered for clinical evaluation.

Yangambin, a new naturally-occurring platelet activating receptor (PAF) receptor antagonist competitively displaced [3H]-PAF from its high affinity binding sites on washed human platelets with a Ki value of 1.1 +/- 0.3 microM (n = 3). Studies carried out in parallel demonstrated that SR 27417, a newly-developed PAF receptor antagonist also antagonized [3H]-PAF binding to these cells with a Ki value of 51 +/- 2 pM. SR 27417 (N-(2-dimethylamino ethyl)-N-(3-pyridinyl methyl) [4-(2,4,6-triisopropyl phenyl) thiazol-2-yl] amine) selectively and competitively inhibited the specific binding of [3H]-PAF on human polymorphonuclear leukocytes (Ki = 65 +/- 5.2 pM) whereas high doses of yangambin remained ineffective. Yangambin inhibited PAF-induced aggregation of human platelets in vitro (IC50 = 1.0 +/- 0.2 microM) but had no effect PAF-induced oxidative burst in human polymorphonuclear leukocytes. In guinea pigs, yangambin inhibited PAF-induced thrombocytopenia but did not affect leukocytopenia whereas SR 27417 afforded complete protection against both PAF-induced thrombocytopenia and leukocytopenia. In conclusion, yangambin discriminates between two different types of PAF receptors on platelets and polymorphonuclear leukocytes and can be considered as the first PAF receptor antagonist described to date exhibiting such an effect.

The involvement of catecholamines in blood neutrophilia observed after administration of platelet activating factor (PAF) to rats was studied. Intravenous (i.v.) injection of PAF (4 micrograms/kg) into naive rats more than doubled the number of neutrophils after 1 h. In contrast, PAF failed to induce neutrophilia in both adrenalectomized rats and those which had their catecholamine stores depleted by reserpine. PAF-induced neutrophilia was not inhibited by the selective antagonism of alpha 1- and alpha 2-adrenoceptors with prazosin and yohimbine, respectively. However, pretreatment with the beta-adrenoceptor antagonist, propranolol, significantly inhibited the phenomenon. Increase in the blood neutrophil counts was also achieved following the i.v. injection of the beta-agonist, salbutamol (1 mg/kg, i.v.). This response was clearly sensitive to propranolol but was not modified in rats submitted to adrenalectomy or reserpine pretreatment. The results suggest that the blood neutrophilia induced by the i.v. administration of PAF in rats is dependent on the stimulation of beta-adrenoceptors by catecholamines released from adrenal glands.

The involvement of platelet-activating factor (PAF) in lipopolysaccharide (LPS)-induced leukocyte accumulation in the rat pleural cavity was investigated. Intrathoracic (i.t.) injection of LPS (250 ng/cavity) induced a marked increase in the number of neutrophils at 1 h, which was maximum within 6-12 h, reducing after 24 h. In parallel, an increase in blood neutrophil counts within 1-6 h, concomitantly with a reduction in the number of these cells in the bone marrow, was observed. The number of eosinophils recovered from LPS-injected pleural cavity increased at 12 h and was maximum within 24-48 h. No change in blood or bone marrow eosinophil counts was detected. The pretreatment with WEB 2086 or PCA 4248 (20 mg/kg) significantly inhibited pleural neutrophil accumulation, blood neutrophilia and the decrease in the marrow neutrophil content, but not eosinophil accumulation. The blood neutrophilia and the decrease in marrow neutrophil counts induced by the intravenous (i.v.) injection of LPS (250 ng) were significantly lower than those observed after i.t. injection. Furthermore, WEB 2086 and PCA 4248 were ineffective against the systemic alteration induced by i.v. LPS. it was concluded that LPS-induced neutrophil, but not eosinophil, accumulation in the pleural cavity is related to the mobilization of neutrophils from the bone marrow and involves PAF dependent mechanisms.

Intrathoracic injection of endotoxin lipopolysaccharide, LPS into rats induced a dose-dependent increase in the number of eosinophils recovered from the pleural cavity. The pleural eosinophil accumulation peaked within 24-48 h, and returned to basal levels within 120 h. This phenomenon was accompanied by mononuclear cell infiltration, and preceded by massive neutrophil accumulation. Pretreatment with indomethacin, BW 755C (a dual cyclo/lipoxygenase inhibitor), BW A4C (a specific lipoxygenase inhibitor) or the platelet activating factor (PAF) antagonists WEB 2086 and PCA 4248 failed to inhibit the endotoxin-induced pleural eosinophilia, whilst dexamethasone (5-10 micrograms/cavity) or cycloheximide (14-28 micrograms/cavity) abolished this phenomenon. Transfer of the cell-free pleural washing from LPS-treated donor rats to normal recipient rats led to a two-fold increase in the eosinophil counts. Treatment of donors, but not recipients, with cycloheximide or dexamethasone inhibited the eosinophil accumulation induced by the pleural washings, indicating that the generation of the eosinophilotactic activity, but not its effects, depends on protein synthesis. This eosinophilotactic activity was maintained after lyophilization and heating (100 degrees C for 30 min), but was destroyed by trypsin. This substance has a molecular weight ranging between 10 and 50 kDa. The available data suggest that the late eosinophil accumulation induced by LPS is independent of arachidonic acid metabolites and PAF, and probably depends on a newly generated heat-stable soluble protein.

The inhibition of the haematological alterations and prevention of death due to systemic anaphylaxis after antigen challenge were investigated in rats after various drug treatments. The i.v. injection of ovalbumin (250 micrograms/kg) into actively sensitized rats induced marked thrombocytopenia and haemoconcentration within 5 min and significant leukocytosis within 30 min, lasting for 2 h after the challenge. Pretreatment with meclizine or terfenadine (15-30 mg/kg i.p.) inhibited antigen-induced haemoconcentration, whereas WEB 2086 (2-10 mg/kg i.p.) and PCA 4248 (5-10 mg/kg p.o.), two platelet-activating factor (PAF) antagonists, interfered with thrombocytopenia only. Azelastine (1-20 mg/kg p.o.) dose dependently inhibited antigen-induced haemoconcentration and thrombocytopenia but failed to block leukocytosis. Azelastine also inhibited the thrombocytopenia observed after the i.v. administration of PAF (4 micrograms/kg). Administration of ovalbumin at a dose of 1.5 mg/kg resulted in a lethal anaphylactic reaction in about 85% of the rats. Pretreatment with WEB 2086 (10 mg/kg i.p.), meclizine (30 mg/kg i.p.) or both increased the survival rate from 15 to 57, 68 and 87%, respectively. Azelastine alone (20 mg/kg p.o.) completely blocked the lethal reaction. It was concluded that the ability of azelastine to antagonize histamine and PAF is important for its effectiveness against anaphylactic shock.