David Henrique Rodrigues

Federal University of Minas Gerais, Cidade de Minas, Minas Gerais, Brazil

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Publications (36)100.94 Total impact

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    ABSTRACT: The pathogenesis of autism spectrum disorder (ASD) is unknown, and the immune system has been appointed to play an important role. The interleukin 33 (IL-33), a member of the IL-1, may act as an alarmin. This study aimed to evaluate plasma levels of IL-33, sST2, and IL-1β in 30 patients with ASD in comparison with 18 controls matched by gender, age and maternal age at childbirth. Patients did not differ from controls in IL-33, sST2, and IL-1β plasma levels. Alarmin levels were not correlated with age, and neither was influenced by clinical parameters. Our results undermine the role of IL-33/ST2 in ASD. Copyright © 2014 Elsevier B.V. All rights reserved.
    Journal of Neuroimmunology 01/2015; 278C:69-72. · 2.79 Impact Factor
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    ABSTRACT: Cognitive dysfunction is a major sign of cerebral malaria (CM). However, the underlying mechanisms of CM cognitive outcome remain poorly understood. A body of evidence suggests that adult neurogenesis may play a role in learning and memory processes. It has also been reported that these phenomena can be regulated by the immune system. We hypothesized that memory dysfunction in CM results from hippocampal neurogenesis impairment mediated by the deregulated immune response during the acute phase of CM. C57Bl/6 mice were infected with Plasmodium berghei ANKA (PbA) strain, using a standardized inoculation of 10(6) parasitized erythrocytes. Long-term working memory was evaluated using the novel object recognition test. The mRNA expression of brain-derived neurotrophic factor (BDNF), tropomyosin-receptor-kinase (TRK-B) and nerve growth factor (NGF) in the frontal cortex and hippocampus was estimated by real-time polymerase chain reaction (PCR). The protein levels of cytokine interleukin-2 (IL-2), IL-4, IL-6, IL-10, interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), and CCL11 and neurotrophins BDNF and NGF were determined using a cytometric bead array (CBA) kit or enzyme-linked immunosorbent assay. Cell viability in the hippocampus was analyzed by Confocal Microscopy. Neurogenesis in the dentate gyrus was determined through quantification of doublecortin (DCX) positive cells. PbA-infected mice presented working memory impairment on day 5 post-infection. At this same time point, CM mice exhibited a decrease in DCX-positive cells in the dentate gyrus in parallel with increased cell death and elevated inflammatory cytokines (IL-6, TNF-α, IFN-γ and CCL11) in the hippocampus and frontal cortex. A significant reduction of BDNF mRNA expression was also found. IL-6 and TNF-α correlated negatively with BDNF and NGF levels in the hippocampus of CM mice. In summary, we provide further evidence that neuroinflammation following PbA-infection influences neurotrophin expression, impairs adult hippocampal neurogenesis and increases hippocampal cell death in association with memory impairment following CM course. The current study identified potential mediators of memory impairment in CM. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.
    Neuroscience 11/2014; 284C:920-933. · 3.33 Impact Factor
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    ABSTRACT: Pneumococcal meningitis is associated with neurologic sequelae, such as, learning and memory impairment. Most currently a nonbacteriolytic antibiotic has been investigated to minimize inflammatory host response and prevented cognitive damage. In the present study, we compared daptomycin (DPTO) or ceftriaxone (CFX) treatment on inflammatory parameters and on blood-brain barrier (BBB) integrity in experimental pneumococcal meningitis. In the first step, the animals received an intracisternal (i.c.) injection of 10 µl of a S. pneumoniae suspension and were treated with CFX or DPTO at 18 h and were killed at 18, 20, 24, 36 and 40 h. In the hippocampus, tumor necrosis factor-alpha (TNF-α), Interleukin-6 (IL-6), IL-10 and brain-derived neurotrophic factor (BDNF) levels were not different between both treatments, however, IL-4 and CINC-1 levels decreased in CFX group. In frontal cortex, TNF-α, IL-4, IL-6, IL-10 and BDNF levels were not different between both treatments. Only cytokine-induced neutrophil chemoattractant-1 (CINC-1) levels decreased at 40 h with CFX treatment. In the second step the animals received DPTO or CFX during 7 days and were killed 10 days after induction. TNF-α, IL-6, IL-10, CINC-1 and BDNF levels were not different between both treatments in the hippocampus, however, IL-4 levels decreased in CFX treatment. In the third step: the animals received by i.c. 10 µl of a S. pneumoniae suspension or artificial CSF and were treated with CFX or DTPO with a single dose of antibiotic and BBB breakdown was assessed; however both antibiotics prevented the BBB disruption. Equally both treatments protected the BBB integrity and there were no significant difference in cytokines production.
    Current Neurovascular Research 05/2014; · 2.74 Impact Factor
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    ABSTRACT: Infection with Plasmodium falciparum may result in severe disease affecting various organs, including liver, spleen and brain, resulting in high morbidity and mortality. P. berghei ANKA (PbA) infection of mice recapitulates many features of severe human malaria. The Aryl Hydrocarbon receptor (AhR) is an intracellular receptor activated by ligands important in the modulation of the inflammatory response. We found AhR knockout (KO) mice infected with PbA displayed increased parasitemia, earlier mortality, enhanced leukocyte-endothelial cell interactions in the brain microvasculature, increased inflammation in brain (IL-17 and IL-6) and liver (IFN-γ and TNF-α) compared to infected wild type (WT) mice. Infected AhR-KO mice also displayed a reduction in cytokines required for host resistance, including TNF-α, IL-1β, IFN-γ, in the brain and spleen. Infection of AhR-KO mice resulted in an increase in Tregs and TGF-β, IL-6 and IL-17 in the brain. AhR modulated basal expression of SOCS3 in spleen and brain and PbA infection resulted in enhanced expression of SOCS3 in the brain, which was absent in infected AhR-KO mice. These data suggest that AhR mediated control of SOCS3 expression is probably involved in the phenotype seen in infected AhR-KO mice. This is, to our knowledge, the first demonstration of a role for AhR in the pathogenesis of malaria.
    Infection and immunity 05/2014; · 4.16 Impact Factor
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    ABSTRACT: The etiopathogenesis of obsessive-compulsive disorder (OCD) remains elusive. Clinical observation of the elevated frequency of obsessive-compulsive symptoms in patients with rheumatic fever, a post-streptococcal autoimmune disease, prompted the study of immune parameters in OCD. Anti-basal ganglia antibodies have been described in a subset of OCD patients. The assessment of circulating cytokines and immune cells confirmed unequivocal changes in at least some patients, although it is difficult to establish a particular immune profile in OCD. Several factors, including the use of psychotropic drugs and the presence of comorbid conditions, seem to influence these immune parameters. © 2014 S. Karger AG, Basel.
    NeuroImmunoModulation 01/2014; 21(2-3):152-8. · 1.84 Impact Factor
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    ABSTRACT: Background and Objective: The etiopathogenesis of autism spectrum disorders (ASD) is largely unknown, but it seems to involve dysfunction in several biological systems. Among many possible biological pathways, the immune system has emerged as potentially involved. Recent studies have shown association between cytokines (molecules that mediate immune cell interaction) and ASD. Adipokines are cytokines secreted mainly by adipose tissue and may have systemic effects. The main objective of this study was to compare the plasma levels of three adipokines between patients with ASD and healthy controls. Another aim was to correlate the levels of these adipokines and the severity of autistic symptoms as measured by the Social Responsiveness Scale (SRS). Methods: We collected plasma from 30 patients and 19 controls and measured the levels of adiponectin, leptin and resistin using a commercially available kit. We also used the SRS as a tool to assess the severity of autistic symptoms. Results: We found decreased levels of resistin, increased levels of leptin and unaltered levels of adiponectin in plasma from ASD subjects in comparison with controls. There was also a negative correlation between the levels of adiponectin and the severity of symptoms as assessed by the SRS. Conclusion: There are significant changes in the plasma levels of adipokines from patients with ASDs. They suggest the occurrence of systemic changes in ASD and may be hallmarks of the disease. © 2013 S. Karger AG, Basel.
    Neuropsychobiology 12/2013; 69(1):6-10. · 2.30 Impact Factor
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    ABSTRACT: Cerebral malaria (CM) is a clinical syndrome resulting from Plasmodium falciparum infection. A wide range of clinical manifestations follow the disease including cognitive dysfunction, seizures and coma. CM pathogenesis remains incompletely understood and without treatment this condition is invariably fatal. Artesunate has been accepted as the most effective drug for treating severe malaria. Besides its antiparasitic activity, an anti-inflammatory property has also been reported. In the current study, the immunomodulatory role of artesunate was investigated using a Plasmodium berghei ANKA model of CM, trough evaluation of behavioural changes and cytokines expression in hippocampus and in frontal cortex. C57Bl/6 mice were infected with P. berghei by intraperitoneal route, using a standardized inoculation of 106 parasitized erythrocytes. Memory function was evaluated using the step-down inhibitory avoidance test. The mRNA expression of IFN-gamma, IL-1beta, IL-6 and TNF in the frontal cortex and hippocampus of control and infected mice on day 5 post-infection were estimated by quantitative real time PCR. Plasmodium berghei -infected mice also received intraperitoneally a single dose of artesunate (32 mg/kg) on day 4 post-infection, and 24 hours after treatment behavioural and immunological analysis were performed. The protein levels of cytokines IL-2, IL-6, IL-10, IL-17, IFN-gamma, TNF in the serum, frontal cortex and hippocampus of controls and P. berghei -infected mice treated or not treated with artesunate were determined using a cytometric bead array (CBA) kit. The survival and neurological symptoms of CM were also registered. CM mice presented a significant impairment of aversive memory compared to controls on day 5 post-infection. A higher mRNA expression of pro-inflammatory cytokines was found in the hippocampus and frontal cortex of infected mice. A single dose of artesunate was also able to decrease the expression of inflammatory cytokines in the hippocampus and frontal cortex of P. berghei-infected mice. In parallel, a significant improvement in neurological symptoms and survival were observed in artesunate treated mice. In summary, the current study provided further evidence that CM affects key brain areas related to cognition process. In addition, different patterns of cytokine expression during the course of CM could be modulated by a single administration of the anti-malarial artesunate.
    Malaria Journal 11/2013; 12(1):388. · 3.49 Impact Factor
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    ABSTRACT: Ischemic stroke may result from transient or permanent reductions of regional cerebral blood flow. Polymorphonuclear neutrophils have been described as the earliest inflammatory cells to arrive in ischemic tissue. CXCR1/2 receptors are involved in the recruitment of these cells. However, the contribution of these chemokine receptors during transient brain ischemia in mice remains poorly understood. In this work, we investigated the effects of reparixin, an allosteric antagonist of CXCR1/2 receptors, in a model of middle cerebral artery occlusion and reperfusion in mice. C57BL/6J male mice treated with reparixin or vehicle were subjected to a middle cerebral artery occlusion procedure 1 h after the treatment. Ninety minutes after ischemia induction, the monofilament that prevented blood flow was removed. Twenty-four hours after the reperfusion procedure, behavioral changes, including motor signs, were analyzed with the SmithKline/Harwell/lmperial College/Royal Hospital/Phenotype Assessment (SHIRPA) battery. The animals were sacrificed, and brain tissue was removed for histological and biochemical analyses. Histological sections were stained with hematoxylin and eosin, neutrophil infiltration was estimated by myeloperoxidase activity and the inflammatory cytokine IL-iβ was measured by ELISA. Pre-treatment with reparixin reduced the motor deficits observed in this model of ischemia and reperfusion. Myeloperoxidase activity and IL-iβ were reduced in the reparixin-treated group. Histological analysis revealed that ischemic injury was also attenuated by reparixin pre-treatment. Our results suggest that the blockade of the CXCR1/2 receptors by reparixin promotes neuroprotective effects by reducing the levels of polymorphonuclear infiltration in the brain and the tissue damage associated with middle cerebral artery occlusion and reperfusion.
    Clinics (São Paulo, Brazil) 03/2013; 68(3):391-4. · 1.59 Impact Factor
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    ABSTRACT: BACKGROUND: The neuroinflammatory response aimed at clearance of herpes simplex virus-1 (HSV-1) plays a key role in the pathogenesis of neuroaxonal damage in herpetic encephalitis. Leukocytes activated in an adaptive immune response access brain tissue by passing through the blood--brain barrier. The chemokine CCL5/RANTES is involved in recruitment of these cells to the brain acting via the receptors CCR1, CCR3 and mainly CCR5. Here, we evaluated the role of CCR5 on traffic of leukocytes in the brain microvasculature, cellular and cytokines profile in a severe form of herpetic encephalitis. RESULTS: Wild type and mice lacking CCR5 (CCR5-/-) were inoculated intracerebrally with 104 PFU of neurotropic HSV-1. We evaluated the traffic of leukocytes in the brain microvasculature using intravital microscopy and the profile of cytokines by Enzyme-Linked Immunosorbent Assay at 1 day post infection. Flow cytometry and histopathological analyses were also carried out in brain tissue. Absence of CCR5 leads to lower viral load and an increased leukocyte adhesion in brain microvasculature, predominantly of neutrophils (CD11+ Ly6G+ cells). Moreover, there was a significant increase in the levels of MIP-1/CCL2, RANTES/CCL5, KC/CXCL1 and MIG/CXCL9 in the brain of infected CCR5-/- mice. CONCLUSIONS: These results suggest that the absence of CCR5 may boost the immune response with a high neutrophil recruitment which most likely helps in viral clearance. Nonetheless, the elevated immune response may be detrimental to the host.
    BMC Neuroscience 02/2013; 14(1):19. · 2.85 Impact Factor
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    ABSTRACT: Sepsis can lead to long-term cognitive changes, including memory and learning deficits, which are known as septic encephalopathy (SE). SE also includes behavioral changes. The underlying mechanism of SE is unknown, and several mechanisms have been proposed. This study investigated late anxiety-like behavior, serum cytokine levels and brain cytokine production in C57BL/6 mice subjected to polymicrobial sepsis induced by sublethal cecum ligature and puncture (CLP). Anxiety-like behavior and locomotor activity were assessed in mice 10 days after sham operation or CLP procedure using the elevated plus maze, contextual fear conditioning, and open field test. Brain and serum concentrations of the cytokines TNF-α, IFN-γ, IL-1β, IL-6, and IL-10 were determined by ELISA. We found that mice subjected to polymicrobial sepsis presented anxiety-like behavior, which was accompanied by increased serum TNF-α and brain TNF-α, IFN-γ, IL-1β, and IL-6 levels, 10 days after the surgical procedure. These findings suggest an involvement of central nervous system inflammatory mediators in the anxiety-like symptoms found in SE.
    Neurotoxicity Research 12/2012; · 3.15 Impact Factor
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    ABSTRACT: Dengue virus is a human pathogen that may cause meningoencephalitis and other neurological syndromes. The current study investigated anxiety-like behavior and expression of proinflammatory cytokines and pro-apoptotic caspase-3 in the hippocampus of C57BL/6 mice infected with non-adapted Dengue virus 3 genotype I (DENV-3) inoculated intracranially with 4×10(3) (plaque-forming unit) PFU. Anxiety-like behavior was assessed in control and DENV-3 infected mice using the elevated plus maze. The open field test was performed to evaluate locomotor activity. Histopathological changes in CA regions of the hippocampus were assessed by haematoxylin and eosin staining. Immunoreactive and protein levels of cleaved caspase-3 were also analyzed in the hippocampus. The mRNA expression of IL-6 and TNF-α in the hippocampus were estimated by quantitative real time (polymerase chain reaction) PCR. All procedures were conducted on day 5 post-infection. We found that DENV-3 infected mice presented higher levels of anxiety in comparison with controls (p≤0.05). No difference in motor activity was found between groups (p=0.77). The infection was followed by a significant increase of TNF-α and IL-6 mRNA expression in the hippocampus (p≤0.05). Histological analysis demonstrated meningoencephalitis with formation of perivascular cuffs, infiltration of immune cells and loss of neurons at CA regions of hippocampus. Numerous caspase-3 positive neurons were visualized at CA areas in DENV-3 infected mice. Marked increase of cleaved caspase-3 levels were observed after infection. This study described anxiety-like behavior, hippocampal inflammation and neuronal apoptosis associated with DENV-3 infection in the central nervous system.
    Behavioural brain research 02/2012; 230(1):237-42. · 3.22 Impact Factor
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    ABSTRACT: The objective of the present study was to determine if there is a relationship between serum levels of brain-derived neurotrophic factor (BDNF) and the number of T2/fluid-attenuated inversion recovery (T2/FLAIR) lesions in multiple sclerosis (MS). The use of magnetic resonance imaging (MRI) has revolutionized the study of MS. However, MRI has limitations and the use of other biomarkers such as BDNF may be useful for the clinical assessment and the study of the disease. Serum was obtained from 28 MS patients, 18-50 years old (median 38), 21 women, 0.5-10 years (median 5) of disease duration, EDSS 1-4 (median 1.5) and 28 healthy controls, 19-49 years old (median 33), 19 women. BDNF levels were measured by ELISA. T1, T2/FLAIR and gadolinium-enhanced lesions were measured by a trained radiologist. BDNF was reduced in MS patients (median [range] pg/mL; 1160 [352.6-2640]) compared to healthy controls (1640 [632.4-4268]; P = 0.03, Mann-Whitney test) and was negatively correlated (Spearman correlation test, r = -0.41; P = 0.02) with T2/FLAIR (11-81 lesions, median 42). We found that serum BDNF levels were inversely correlated with the number of T2/FLAIR lesions in patients with MS. BDNF may be a promising biomarker of MS.
    Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas / Sociedade Brasileira de Biofisica ... [et al.] 12/2011; 45(1):68-71. · 1.08 Impact Factor
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    ABSTRACT: Multiple sclerosis is a neuroinflammatory disease that results in serious neurological disability. Besides physical impairment, behavioral symptoms are also common in patients with multiple sclerosis. Experimental autoimmune encephalomyelitis (EAE) is considered to be a model of multiple sclerosis and mimics the main features of the disease, such as demyelination and motor impairment. In this work, we aimed to study behavioral parameters in animals with EAE using the MOG(35-55) model in C57BL/6 mice. We analyzed memory and anxiety in animals using the elevated plus maze, the step down inhibitory avoidance task and the memory recognition test. No differences in any tests were found when comparing controls and animals induced with EAE. Therefore, we conclude that behavioral changes in animals with EAE induced with MOG(35-55) are probably subtle or absent.
    Arquivos de neuro-psiquiatria 12/2011; 69(6):938-42. · 0.55 Impact Factor
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    ABSTRACT: Cerebral malaria is a severe form of the disease that may result, in part, from an overt inflammatory response during infection by Plasmodium falciparum. The understanding of the pathogenesis of cerebral malaria may aid in the development of better therapeutic strategies for patients. The immune response in cerebral malaria involves elevation of circulating levels of cytokines and chemokines associated with leukocyte accumulation and breakdown of the blood-brain barrier in the central nervous system. Platelet-activating factor (PAF) is a mediator of inflammation shown to orchestrate inflammatory processes, including recruitment of leukocytes and increase of vascular permeability. Using mice lacking the PAF receptor (PAFR(-/-)), we investigated the relevance of this molecule for the outcome and the neuroinflammatory process triggered by P. berghei ANKA, an experimental model of cerebral malaria. In PAFR(-/-) mice, lethality was markedly delayed and brain inflammation was significantly reduced, as demonstrated by histology, accumulation, and activation of CD8(+) T cells, changes in vascular permeability and activation of caspase-3 on endothelial cells and leukocytes. Similarly, treatment with the PAFR antagonist UK-74,505 delayed lethality. Taken together, the results suggest that PAFR signaling is crucial for the development of experimental cerebral malaria. Mechanistically, PAFR activation is crucial for the cascade of events leading to changes in vascular permeability, accumulation, and activation of CD8(+) T cells and apoptosis of leukocytes and endothelial cells.
    American Journal Of Pathology 11/2011; 180(1):246-55. · 4.60 Impact Factor
  • European Neuropsychopharmacology 09/2011; 21. · 5.40 Impact Factor
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    ABSTRACT: Herpes simplex virus-1 (HSV-1) is a pathogen that may cause severe encephalitis in humans. In this study, we aimed to investigate the role of interleukin-4 (IL-4) in a model of HSV-1 brain infection. IL-4 knockout (IL-4-/-) and wild type (WT) C57BL/6 mice were inoculated with 10(4) plaque-forming units of HSV-1 by the intracranial route. Histopathologic analysis revealed a distinct profile of infiltrating cells at 3 days post-infection (dpi). Infected WT mice presented mononuclear inflammatory cells while IL-4-/- mice developed meningoencephalitis with predominance of neutrophils. IL-4-/- mice had diminished leukocyte adhesion at 3 dpi when compared to infected WT animals in intravital microscopy study. Conversely no differences were found in cerebral levels of CXCL1, CXCL9, CCL3, CCL5 and TNF-α between WT and IL-4-/- infected mice. IL-4 may play a role in the recruitment of cells into central nervous system in this acute model of severe encephalitis caused by HSV-1.
    Arquivos de neuro-psiquiatria 04/2011; 69(2A):237-41. · 0.55 Impact Factor
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    ABSTRACT: Dengue, one of the most important arboviral diseases of humans, may cause severe systemic disease. Although dengue virus (DENV) has been considered to be a non-neurotropic virus, dengue infection has been associated recently with a series of neurological syndromes, including encephalitis. In this work, we evaluated behavioral changes and inflammatory parameters in C57BL/6 mice infected with non-adapted dengue virus 3 (DENV-3) genotype I. C57BL/6 mice received 4×10(3) PFU of DENV-3 by an intracranial route. We evaluated the trafficking of leukocytes in brain microvasculature using intravital microscopy, and evaluated chemokine and cytokine profiling by an ELISA test at 3 and 6 days post infection (p.i.). Furthermore, we determined myeloperoxidase activity and immune cell populations, and also performed histopathological analysis and immunostaining for the virus in brain tissue. All animals developed signs of encephalitis and died by day 8 p.i. Motor behavior and muscle tone and strength parameters declined at day 7 p.i. We observed increased leukocyte rolling and adhesion in brain microvasculature of infected mice at days 3 and 6 p.i. The infection was followed by significant increases in IFN-γ, TNF-α, CCL2, CCL5, CXCL1, and CXCL2. Histological analysis showed evidence of meningoencephalitis and reactive gliosis. Increased numbers of neutrophils, CD4+ and CD8+ T cells were detected in brain of infected animals, notably at day 6 p.i. Cells immunoreactive for anti-NS-3 were visualized throughout the brain. Intracerebral infection with non-adapted DENV-3 induces encephalitis and behavioral changes that precede lethality in mice.
    Journal of Neuroinflammation 03/2011; 8:23. · 4.90 Impact Factor
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    ABSTRACT: Cerebral malaria (CM) is a severe complication resulting from Plasmodium falciparum infection. The underlying mechanisms of CM pathogenesis remain incompletely understood. The imbalance between the release of proinflammatory and anti-inflammatory cytokines has been associated with central nervous system dysfunction found in human and experimental CM. The current study investigated anxiety-like behavior, histopathological changes and release of brain cytokines in C57BL/6 mice infected with Plasmodium berghei strain ANKA (PbA). Anxiety-like behavior was assessed in control and PbA-infected mice using the elevated plus maze test. Histopathological changes in brain tissue were assessed by haematoxylin and eosin staining. Brain concentration of the cytokines IL-1β, IL-4, IL-10, TNF-α and IFN-γ was determined by ELISA. We found that PbA-infected mice on day 5 post-infection presented anxiety symptoms, histopathological alterations in the brainstem, cerebrum and hippocampus and increased cerebral levels of proinflammatory cytokines IL-1β and TNF-α. These findings suggest an involvement of central nervous system inflammatory mediators in anxiety symptoms found in CM.
    Neuroscience Letters 03/2011; 491(3):202-6. · 2.06 Impact Factor
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    ABSTRACT: Experimental autoimmune encephalomyelitis (EAE) is a condition induced in some susceptible species to the study of multiple sclerosis (MS). The platelet activating factor (PAF) is an important mediator of immune responses and seems to be involved in MS. However, the participation of PAF in EAE and MS remains controversial. Thus, in this study, we aimed to evaluate the role of PAF receptor in the pathogenesis of EAE. EAE was induced using an emulsion containing MOG(35-55). EAE-induced PAF receptor knock out (PAFR(-/-)) mice presented milder disease when compared to C57BL/6 wild type (WT) animals. PAFR(-/-) animals had lower inflammatory infiltrates in central nervous system (CNS) tissue when compared to WT mice. However, intravital microscopy in cerebral microvasculature revealed similar levels of rolling and adhering leukocytes in both WT and PAFR(-/-) mice. Interleukine (IL)-17 and chemokines C-C motif legends (CCL)2 and CCL5 were significantly lower in PAFR(-/-) mice when compared to WT mice. Brain infiltrating cluster of differentiation (CD)4(+) leukocytes and IL-17(+) leukocytes was diminished in PAFR(-/-) when compared to WT mice. Taken together, our results suggest that PAF receptor is important in the induction and development of EAE, although it has no influence in rolling and adhesion steps of cell recruitment. The absence of PAF receptor results in milder disease by altering the type of inflammatory mediators and cells that are present in CNS tissue.
    Brain research 02/2011; 1385:298-306. · 2.83 Impact Factor
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    ABSTRACT: To evaluate the effects of sepsis on brain microvasculature leukocyte rolling and adherence, myeloperoxidase (MPO) activity, cytokine and chemokine concentrations, and behavioral screening 6, 12, and 24 h after sepsis induction. C57BL/6 mice or Wistar rats underwent cecal ligation and perforation (CLP) or sham operation. At 6, 12, and 24 h after sepsis induction, intravital microscopy was performed in the mice brain microvasculature to evaluate leukocyte rolling and adherence. Animals were killed and had the brain removed to determine MPO activity and the levels of cytokines and chemokines. A behavioral screening was also performed in a separate cohort of animals. Blood-brain barrier (BBB) permeability and cytokines and chemokines were determined in different brain regions in Wistar rats. There was a decrease in circulating leukocyte levels at 6, 12, and 24 h, an increase in rolling and adhesion of leukocytes in the brain microvasculature, followed by an increase in brain MPO activity. In addition, there was an increase in both brain cytokines and chemokines at different times. There was a decrease in the neuropsychiatric state muscle tone and strength only at 6 h, and a decrease in the autonomous function at 6 and 12 h. The pattern of brain cytokines and chemokines, and BBB permeability between the analyzed regions seemed to be similar with minor differences. During sepsis the brain's production of cytokines and chemokines is an early event and it seemed to participate both in central nervous system (CNS) dysfunction and BBB permeability alterations, reinforcing the role of brain inflammatory response in the acute CNS dysfunction associated with sepsis.
    European Journal of Intensive Care Medicine 02/2011; 37(4):711-8. · 5.17 Impact Factor