Francesco Langone

University of Brasília, Brasília, Distrito Federal, Brazil

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Publications (38)101.06 Total impact

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    ABSTRACT: Quinolinic acid (QA) striatal lesion in rodents induces neuronal death, astrogliosis and migration of neuroblasts from subventricular zone to damaged striatum. These phenomena occur in some human neurodegenerative illnesses, but the underlying mechanisms are unknown. We investigated the effect of AG490, a Janus-kinase 2 (JAK2) inhibitor, on astrogliosis, neuronal loss and neurogenesis in the striatum of adult mice after unilateral infusion of QA (30nmol). Animals were given subcutaneous injections of AG490 (10mg/kg) or vehicle immediately after lesion and then once daily for six days. Brain sections were used for neuronal stereological quantification, immunohistochemical and Western Blotting analyses for GFAP and doublecortin, markers of astrocytes and neuroblasts, respectively. The total area of doublecortin-positive cells (ADPC) and the number of neurons (NN) in the lesioned (L) and contralateral (CL) sides were evaluated. Neurogenesis index (NI=ADPC(L)/ADPC(CL)) and neuronal ratio (NR=NN(L)/NN(CL)) were calculated. After QA administration, blotting for GFAP showed an ipsilateral decrease of 19% in AG490- vs vehicle-treated animals. NR was 25% higher in mice given AG490 vs controls given vehicle. NI showed a decrease of 21% in AG490- vs vehicle-treated mice. Our results indicate that JAK2 inhibition reduces QA lesion and suggest that astrogliosis may impair neuronal survival in this model.
    Journal of chemical neuroanatomy 02/2013; · 1.75 Impact Factor
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    ABSTRACT: Temporal lobe epilepsy (TLE) is the most common type of human epilepsy and has been related with extensive loss of hippocampal pyramidal and dentate hilar neurons and gliosis. Many characteristics of TLE are reproduced in the pilocarpine model of epilepsy in mice. This study analyzed the neuronal damage, assessed with Fluoro-Jade (FJB) and cresyl violet, and gliosis, investigated with glial fibrilary acidic protein (GFAP) immunohistochemistry, occurring in the hippocampal formation of mice at 3, 6, 12 and 24h, 1 and 3 weeks after the pilocarpine-induced status-epilepticus (SE) onset. The maximum neuronal damage score and the FJB-positive neurons peak were found in the hilus of dentate gyrus 3 and 12 h after SE onset (P<0.05), respectively. At 1 week after SE onset, the greatest neuronal damage score was detected in the CA1 pyramidal cell layer and the greatest numbers of FJB-positive neurons were found both in the CA1 and CA3 pyramidal cell layers (P<0.05). The molecular, CA3 and CA1 pyramidal cell layers expressed highest presence of GFAP immunoreaction at 1 and 3 weeks after SE onset (P<0.05). Our findings show that, depending on the affected area, neuronal death and gliosis can occur within few hours or weeks after SE onset. Our results corroborate previous studies and characterize short time points of temporal evolution of neuropathological changes after the onset of pilocarpine-induced SE in mice and evidences that additional studies of this temporal evolution may be useful to the comprehension of the cellular mechanisms underlying epileptogenesis.
    Brain research 07/2012; 1470:98-110. · 2.46 Impact Factor
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    ABSTRACT: Brain-derived neurotrophic factor (BDNF) is encoded by multiple BDNF transcripts, whose function is unclear. We recently showed that a subset of BDNF transcripts can traffic into distal dendrites in response to electrical activity, while others are segregated into the somatoproximal domains. Physical exercise and antidepressant treatments exert their beneficial effects through upregulation of BDNF, which is required to support survival and differentiation of newborn dentate gyrus (DG) neurons. While these DG processes are required for the antidepressant effect, a role for CA1 in antidepressant action has been excluded, and the effect on CA3 neurons remains unclear. Here, we show for the first time that physical exercise and antidepressants induce local increase of BDNF in CA3. Voluntary physical exercise for 28 consecutive days, or 2-week treatment with 10 mg/kg per day fluoxetine or reboxetine, produced a global increase of BDNF mRNA and protein in the neuronal somata of the whole hippocampus and a specific increase of BDNF in dendrites of CA3 neurons. This increase was accounted for by BDNF exon 6 variant. In cultured hippocampal neurons, application of serotonin or norepinephrine (10-50 μM) induced increase in synaptic transmission and targeting of BDNF mRNA in dendrites. The increased expression of BDNF in CA3 dendrites following antidepressants or exercise further supports the neurotrophin hypothesis of antidepressants action and confirms that the differential subcellular localization of BDNF mRNA splice variants provides a spatial code for a selective expression of BDNF in specific subcellular districts. This selective expression may be exploited to design more specific antidepressants.
    Neuropsychopharmacology: official publication of the American College of Neuropsychopharmacology 02/2012; 37(7):1600-11. · 8.68 Impact Factor
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    ABSTRACT: Clinical studies show an evident antidepressive effect of physical exercise and animal research corroborate such evidence. However, the neurobiological mechanisms underlying the antidepressive effect of exercise are not completely understood. Notwithstanding, it is known that exercise increases brain-derived neurotrophic factor (BDNF) expression in the hippocampus similarly to antidepressant drugs. BDNF is synthesized as a precursor molecule that undergoes a proteolytic cleavage to generate either a mature or a truncated isoform. Precursor and mature BDNF are assumed to elicit opposing biological effects in neuroplasticity. In the present study we investigated the effect of voluntary physical activity on precursor and mature brain-derived neurotrophic factor levels and on proBDNF cleavage related genes, p11 and tissue plasminogen activator (tPA), as well as the antidepressive and cognitive effects of voluntary physical activity. Mice had access to mobile or locked running wheels for 28 days and were submitted to forced-swim, tail suspension and water maze tests. Their hippocampi were dissected and analyzed by Western blot and real time RT-PCR. Voluntary physical activity, but not locked wheel exposure, induced a robust increase in hippocampal mature BDNF protein levels, as well as in p11 and tPA mRNA expression; and also promoted antidepressive effects and improved learning, when compared with sedentary mice. On the other hand, there were no significant differences between any groups in the expression of precursor or truncated isoforms of BDNF. Our data suggest that the antidepressive effect of the physical exercise may depend, at least in part, on changes in BDNF post-translational processing.
    Neuroscience 02/2011; 180:9-18. · 3.12 Impact Factor
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    ABSTRACT: Recent studies have emphasized the beneficial effects of the vascular endothelial growth factor (VEGF) on neurone survival and Schwann cell proliferation. VEGF is a potent angiogenic factor, and angiogenesis has long been recognized as an important and necessary step during tissue repair. Here, we investigated the effects of VEGF on sciatic nerve regeneration. Using light and electron microscopy, we evaluated sciatic nerve regeneration after transection and VEGF gene therapy. We examined the survival of the neurones in the dorsal root ganglia and in lumbar 4 segment of spinal cord. We also evaluated the functional recovery using the sciatic functional index and gastrocnemius muscle weight. In addition, we evaluated the VEGF expression by immunohistochemistry. Fluorescein isothiocyanate-dextran (FITC-dextran) fluorescence of nerves and muscles revealed intense staining in the VEGF-treated group. Quantitative analysis showed that the numbers of myelinated fibres and blood vessels were significantly higher in VEGF-treated animals. VEGF also increased the survival of neurone cell bodies in dorsal root ganglia and in spinal cord. The sciatic functional index and gastrocnemius muscle weight reached significantly higher values in VEGF-treated animals. We demonstrate a positive relationship between increased vascularization and enhanced nerve regeneration, indicating that VEGF administration can support and enhance the growth of regenerating nerve fibres, probably through a combination of angiogenic, neurotrophic and neuroprotective effects.
    Neuropathology and Applied Neurobiology 01/2011; 37(6):600-12. · 4.84 Impact Factor
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    ABSTRACT: Enhancement of sciatic nerve regeneration after vascular endothelial growth factor (VEGF) gene therapy Aims: Recent studies have emphasized the beneficial effects of the vascular endothelial growth factor (VEGF) on neurone survival and Schwann cell proliferation. VEGF is a potent angiogenic factor, and angiogenesis has long been recognized as an important and necessary step during tissue repair. Here, we investigated the effects of VEGF on sciatic nerve regeneration. Methods: Using light and electron microscopy, we evaluated sciatic nerve regeneration after transection and VEGF gene therapy. We examined the survival of the neurones in the dorsal root ganglia and in lumbar 4 segment of spinal cord. We also evaluated the functional recovery using the sciatic functional index and gastrocnemius muscle weight. In addition, we evaluated the VEGF expression by immu-nohistochemistry. Results: Fluorescein isothiocyanate-dextran (FITC-dextran) fluorescence of nerves and muscles revealed intense staining in the VEGF-treated group. Quantitative analysis showed that the numbers of myelinated fibres and blood vessels were significantly higher in VEGF-treated animals. VEGF also increased the survival of neurone cell bodies in dorsal root ganglia and in spinal cord. The sciatic functional index and gastrocne-mius muscle weight reached significantly higher values in VEGF-treated animals. Conclusion: We demonstrate a positive relationship between increased vascularization and enhanced nerve regeneration, indicating that VEGF administration can support and enhance the growth of regenerating nerve fibres, probably through a combi-nation of angiogenic, neurotrophic and neuroprotective effects.
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    ABSTRACT: Peripheral nerves possess the capacity of self-regeneration after traumatic injury. Nevertheless, the functional outcome after peripheral-nerve regeneration is often poor, especially if the nerve injuries occur far from their targets. Aiming to optimize axon regeneration, we grafted bone-marrow-derived cells (BMDCs) into a collagen-tube nerve guide after transection of the mouse sciatic nerve. The control group received only the culture medium. Motor function was tested at 2, 4, and 6 weeks after surgery, using the sciatic functional index (SFI), and showed that functional recovery was significantly improved in animals that received the cell grafts. After 6 weeks, the mice were anesthetized, perfused transcardially, and the sciatic nerves were dissected and processed for transmission electron microscopy and light microscopy. The proximal and distal segments of the nerves were compared, to address the question of improvement in growth rate; the results revealed a maintenance and increase of nerve regeneration for both myelinated and non-myelinated fibers in distal segments of the experimental group. Also, quantitative analysis of the distal region of the regenerating nerves showed that the numbers of myelinated fibers, Schwann cells (SCs) and g-ratio were significantly increased in the experimental group compared to the control group. The transdifferentiation of BMDCs into Schwann cells was confirmed by double labeling with S100/and Hoechst staining. Our data suggest that BMDCs transplanted into a nerve guide can differentiate into SCs, and improve the growth rate of nerve fibers and motor function in a transected sciatic-nerve model.
    Micron 10/2010; 41(7):783-90. · 1.88 Impact Factor
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    ABSTRACT: Every year traumatic peripheral nerve injuries (TPNI) result in considerable physical disability across the world; the mechanisms of plasticity and reorganization of spinal cord circuits following such injuries are complex and not completely understood. A comparative proteome analysis between neonatal rats submitted to peripheral lesion and controls was performed; a number of differentially expressed proteins involved in oxidative stress response, energy metabolism and cytoskeleton rearrangement were revealed, which may support future studies to help in the understanding and a posteriori the treatment of TPNI.
    Journal of Neural Transmission 04/2010; 117(6):689-93. · 3.05 Impact Factor
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    ABSTRACT: Inducible nitric oxide synthase (iNOS) and tumor necrosis factor-alpha (TNF-alpha) are pleiotropic molecules with widespread action in autoimmune diseases. This study characterizes the distribution of iNOS and TNF-alpha in the spinal nerve roots, dorsal root ganglia and sciatic nerve of Lewis rats during experimental autoimmune neuritis (EAN). Macrophages and neutrophils were identified by immunofluorescence as cellular sources of iNOS and TNF-alpha at various stages of EAN induced by synthetic peptide 26. As the disease progressed, iNOS- and TNF-alpha-bearing cells gradually infiltrated the cauda equina, dorsal root ganglia, Th12-L3 spinal roots, and the sciatic nerve. A severer EAN profile developed when more iNOS- and TNF-alpha-bearing cells were present, and the recovery from EAN was related to the disappearance of these cells and the regeneration of nerve fibers. This is the first report to show iNOS- and TNF-alpha-immunoreactive cells in dorsal root ganglia during EAN, suggesting an underlying pathology for the neuropathic pain behavior in EAN. Our results suggest that the cells bearing iNOS and TNF-alpha in the different parts of the peripheral nervous system are involved in the development of the clinical signs observed at each stage of EAN.
    NeuroImmunoModulation 10/2009; 17(1):56-66. · 1.84 Impact Factor
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    ABSTRACT: Ciliary neurotrophic factor (CNTF) regulates the differentiation and survival of a wide spectrum of developing and adult neurons, including motor neuron loss after injury. We recently described a cell-penetrant recombinant human CNTF (rhCNTF) molecule, formed by fusion with the human immunodeficiency virus-1 transactivator of transcription (TAT) protein transduction domain (TAT-CNTF) that, upon subcutaneous administration, retains full neurotrophic activity without cytokine-like side-effects. Although the CNTF receptor is present in hypothalamic nuclei, which are involved in the control of energy, rhCNTF but not TAT-CNTF stimulates signal transducers and activators of transcription 3 phosphorylation in the rat hypothalamus after subcutaneous administration. This could be due limited TAT-CNTF distribution in the hypothalamus and/or altered intracellular signaling by the fusion protein. To explore these possibilities, we examined the effect of intracerebroventricular administration of TAT-CNTF in male adult rats. TAT-CNTF-induced weight loss, although the effect was smaller than that seen with either rhCNTF or leptin (which exerts CNTF-like effects via its receptor). In contrast to rhCNTF and leptin, TAT-CNTF neither induced morphological changes in adipose tissues nor increased uncoupling protein 1 expression in brown adipose tissue, a characteristic feature of rhCNTF and leptin. Acute intracerebroventricular administration of TAT-CNTF induced a less robust phosphorylation of signal transducers and activators of transcription 3 in the hypothalamus, compared with rhCNTF. The data show that fusion of a protein transduction domain may change rhCNTF CNS distribution, while further strengthening the utility of cell-penetrating peptide technology to neurotrophic factor biology beyond the neuroscience field.
    Journal of Neurochemistry 08/2009; 110(5):1557-66. · 3.97 Impact Factor
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    ABSTRACT: Exposure of the spinal cord in myelomeningocele (MM) throughout gestation increases spinal injury. Astrocyte activation evidenced by glial fibrillary acidic proteins (GFAP) indicates the extent of injury. Corticosteroids modulate GFAP synthesis, but their effect in MM is unclear. The purpose of this study was to evaluate the GFAP expression in a fetal rat model of dysraphism and the effect of corticosteroid treatment on this marker and on clinical neurological disabilities. Dysraphism was surgically created in 2 groups of 48 rat fetuses; group 1: control, and group 2: treated with corticosteroid. Each group was subdivided into fetuses with surgically created MM, controls and shams on day 18.5 of gestation (term = 22 days). Fetuses were harvested on day 21.5, examined for evidence of neurological deficits, and the following clinical parameters were registered: kyphosis, tail deformities, leg deformities, leg paralysis or paresis and pain perception. The fetuses were fixed for GFAP immunostaining. All fetuses with MM in group 1 presented neurological deficits and glial reactions with GFAP expression, as opposed to controls and shams. In group 2, corticosteroid treatment prevented some neurological deficits (18-25%), reducing glial response and GFAP expression. Experimentally induced dysraphism in the rat fetus is related to glial response and increased GFAP expression in the spinal cord. Corticoid treatment clinically improved nerve injury in some fetuses. It reduced glial reaction and GFAP expression.
    Pediatric Neurosurgery 07/2009; 45(3):198-204. · 0.42 Impact Factor
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    ABSTRACT: Ciliary neurotrophic factor (CNTF) is a multifunctional cytokine that can regulate the survival and differentiation of many types of developing and adult neurons. CNTF prevents the degeneration of motor neurons after axotomy and in mouse mutant progressive motor neuronopathy, which has encouraged trials of CNTF for human motor neuron disease. Given systemically, however, CNTF causes severe side effects, including cachexia and a marked immune response, which has limited its clinical application. The present work describes a novel approach for administering recombinant human CNTF (rhCNTF) while conserving neurotrophic activity and avoiding deleterious side effects. rhCNTF was fused to a protein transduction domain derived from the human immunodeficiency virus-1 TAT (transactivator) protein. The resulting fusion protein (TAT-CNTF) crosses the plasma membrane within minutes and displays a nuclear localization. TAT-CNTF was equipotent to rhCNTF in supporting the survival of cultured chicken embryo dorsal root ganglion neurons. Local or subcutaneous administration of TAT-CNTF, like rhCNTF rescued motor neurons from death in neonatal rats subjected to sciatic nerve transection. In contrast to subcutaneous rhCNTF, which caused a 20-30% decrease in body weight in neonatal rats between postnatal days 2 and 7 together with a considerable fat mobilization in brown adipose tissue, TAT-CNTF lacked such side effects. Together, these results indicate that rhCNTF fused with the protein transduction domain/TAT retains neurotrophic activity in the absence of CNTFs cytokine-like side effects and may be a promising candidate for the treatment of motor neuron and other neurodegenerative diseases.
    Journal of Neurochemistry 05/2009; 109(6):1680-90. · 3.97 Impact Factor
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    ABSTRACT: CNTF is a cytokine that promotes survival and/or differentiation in many cell types, including rat pancreatic islets. In this work, we studied the mechanism of CNTF signal in neonatal rats pancreatic islets isolated by the collagenase method and cultured for 3 days in RPMI medium without (CTL) or with 1 nM of CNTF. The medium contained, when necessary, specific inhibitors of the PI3K, MAPK and JAK/STAT3 pathways. mRNA expression (RT-PCR) and protein phosphorylation (Western blot) of Akt, ERK1/2 and STAT3, and SOCS-3 (RT-PCR and Western blot), as well as glucose-stimulated insulin secretion (GSIS) (Radioimmunoassay), were analyzed. Our results showed that Akt, ERK1 and STAT3 mRNA expression, as well as phosphorylated Akt and ERK1/2, was not affected by CNTF treatment. CNTF increased cytoplasmatic and nuclear phosphorylated STAT3, and the SOCS3 mRNA and protein expression. In addition, CNTF lowered apoptosis and impaired GSIS. These effects were blocked by the JAK inhibitor, AG490 and by the STAT3 inhibitor Curcumin, but not by the MAPK inhibitor, PD98059, nor by the PI3K inhibitor, Wortmannin. In conclusion, CNTF signals through the JAK2/STAT3 cascade, increases SOCS3 expression, impairs GSIS and protects neonatal pancreatic rat islets from cytokine-induced apoptosis. These findings indicate that CNTF may be a potential therapeutic tool against Type 1 and/or Type 2 diabetes.
    Cytokine 05/2009; 46(1):65-71. · 2.52 Impact Factor
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    ABSTRACT: Voluntary physical activity improves memory and learning ability in rodents, whereas status epilepticus has been associated with memory impairment. Physical activity and seizures have been associated with enhanced hippocampal expression of BDNF, indicating that this protein may have a dual role in epilepsy. The influence of voluntary physical activity on memory and BDNF expression has been poorly studied in experimental models of epilepsy. In this paper, we have investigated the effect of voluntary physical activity on memory and BDNF expression in mice with pilocarpine-induced epilepsy. Male Swiss mice were assigned to four experimental groups: pilocarpine sedentary (PS), pilocarpine runners (PRs), saline sedentary (SS) and saline runners (SRs). Two days after pilocarpine-induced status epilepticus, the affected mice (PR) and their running controls (SR) were housed with access to a running wheel for 28 days. After that, the spatial memory and the expression of the precursor and mature forms of hippocampal BDNF were assessed. PR mice performed better than PS mice in the water maze test. In addition, PR mice had a higher amount of mature BDNF (14kDa) relative to the total BDNF (14kDa+28kDa+32kDa forms) content when compared with PS mice. These results show that voluntary physical activity improved the spatial memory and increased the hippocampal content of mature BDNF of mice with pilocarpine-induced status epilepticus.
    Behavioural brain research 05/2009; 203(2):165-72. · 3.22 Impact Factor
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    ABSTRACT: Most reports of autoimmune response during infection with the parasite Trypanosoma cruzi have dealt with the cardiomyopathic form of Chagas' disease, but little is known about the mechanisms of tissue damage involved in the gastrointestinal form, which was studied here. Chronically infected patients with a severe gastrointestinal form of Chagas' disease present increased antibody production and proliferative responses to peripheral myelin components, such as myelin basic protein (MBP), which is homologous to the P1 protein fraction of peripheral myelin. T lymphocytes preferentially recognize a region on the MBP molecule (1-30), which suggests that the MBP is a potential target on the peripheral nerve for autoimmune reactions in patients with gastrointestinal lesions resulting from Chagas' disease.
    NeuroImmunoModulation 01/2009; 16(1):54-62. · 1.84 Impact Factor
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    ABSTRACT: Ciliary neurotrophic factor (CNTF) is a cytokine that plays a neuroprotective role in relation to axotomized motoneurons. We determined the effect of daily subcutaneous doses of CNTF (1.2 microg/g for 5 days; N = 13) or PBS (N = 13) on the levels of mRNA for Bcl-2 and Bax, as well as the expression and inter-association of Bcl-2 and Bax proteins, and the survival of motoneurons in the spinal cord lumbar enlargement of 2-day-old Wistar rats after sciatic nerve transection. Five days after transection, the effects were evaluated on histological and molecular levels using Nissl staining, immunoprecipitation, Western blot analysis, and reverse transcriptase-polymerase chain reaction. The motoneuron survival ratio, defined as the ratio between the number of motoneurons counted on the lesioned side vs those on the unlesioned side, was calculated. This ratio was 0.77 +/- 0.02 for CNTF-treated rats vs 0.53 +/- 0.02 for the PBS-treated controls (P < 0.001). Treatment with CNTF modified the level of mRNA, with the expression of Bax RNA decreasing 18% (with a consequent decrease in the level of Bax protein), while the expression of Bcl-2 RNA was increased 87%, although the level of Bcl-2 protein was unchanged. The amount of Bcl-2/Bax heterodimer increased 91% over that found in the PBS-treated controls. These data show, for the first time, that the neuroprotective effect of CNTF on neonatal rat axotomized motoneurons is associated with a reduction in free Bax, due to the inhibition of Bax expression, as well as increased Bcl-2/Bax heterodimerization. Thus, the neuroprotective action of the CNTF on axotomized motoneurons can be related to the inhibition of this apoptotic pathway.
    Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas / Sociedade Brasileira de Biofisica ... [et al.] 12/2008; 41(11):1024-8. · 1.08 Impact Factor
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    ABSTRACT: Mutations in LGI1 were described in patients with autosomal dominant partial epilepsy with auditory features (ADPEAF), and recent clinical findings have implicated LGI1 in human brain development. However, the precise role of LGI1 in epileptogenesis remains largely unknown. The objective of this study was to determine the expression pattern of Lgi1 in mice brain during development and in adult animals. Real-time polymerase chain reaction (PCR) quantification and Western blot experiments showed a relative low expression during intrauterine stages, increasing until adulthood. In addition, we did not find significant differences between left and right hemispheres. The hippocampus presented higher levels of Lgi1 expression when compared to the neocortex and the cerebellum of adult animals; however, these results did not reach statistical significance. This study was the first to determine a specific profile of Lgi1 gene expression during central nervous system development, which suggests a possible inhibitory function in latter stages of development. In addition, we did not find differences in hemispheric expression that could explain the predominance of left-sided abnormalities in patients with ADPEAF.
    Journal of Molecular Neuroscience 07/2008; 35(3):323-9. · 2.89 Impact Factor
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    ABSTRACT: Amniotic fluid (AF) and its components, such as fetal urine and meconium, may lead to intestinal alterations in gastroschisis, which cause immaturity of the myenteric plexus and consequent intestinal hypomotility and malabsorption. In this study we identified morphological and histological alterations of the intestine and the myenteric plexus with two different times of exposure to AF. The experimental gastroschisis was achieved at two different gestational ages, on day 18.5 (E18.5) and day 19.5 (E19.5) of gestation, in fetal rats which were divided into 3 subgroups: control, sham and gastroschisis. We measured fetal body weight (BW), intestinal weight (IW) and intestinal length (IL). The layers of intestinal wall and myenteric plexus were evaluated by hematoxylin and eosin staining (HE staining) and immunofluorescence (alpha-internexin), respectively. BW was not significantly different among the control, sham and gastroschisis groups at both ages. IW and IL were larger and shorter, respectively, in the gastroschisis fetuses (p < 0.001) at both ages. Intestinal diameters and wall layers presented significant differences among control, sham and gastroschisis fetuses at both ages (p < 0.001), but the time of exposure to AF compromised the serous membrane, D-II (diameter II, p < 0.001) and IL (p = 0.001). alpha-Internexin presented more intensive immunoreactivity in gastroschisis fetuses at E18.5. In gastroschisis, the longer the time of exposure to AF, the more severe bowel impairment will be, especially with regard to IL and the serous layer, and the more immature the myenteric plexus will be.
    Fetal Diagnosis and Therapy 01/2008; 23(1):60-8. · 1.90 Impact Factor
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    ABSTRACT: Ciliary neurotrophic factor (CNTF) belongs to the cytokine family and increases neuron differentiation and/or survival. Pancreatic islets are richly innervated and express receptors for nerve growth factors (NGFs) and may undergo neurotypic responses. CNTF is found in pancreatic islets and exerts paracrine effects in neighboring cells. The aim of this study was to investigate possible effects of CNTF on neonatal rat pancreatic islet differentiation and/or survival. For this purpose, we isolated pancreatic islets from neonatal rats (1-2 days old) by the collagenase method and cultured for 3 days in RPMI medium with (CNTF) or without (CTL) 1 nM CNTF. Thereafter, glucose-stimulated insulin secretion (RIA), general metabolism by (NAD(P)H production; MTS), glucose metabolism ((14)CO(2) production), gene (RT-PCR), protein expression (western blotting), caspase-3 activity (Asp-Glu-Val-Asp (DEVD)), and apoptosis (DNA fragmentation) were analyzed. Our results showed that CNTF-treated islets demonstrated reduced glucose-induced insulin secretion. CNTF treatment did not affect glucose metabolism, as well as the expression of mRNAs and proteins that are crucial for the secretory process. Conversely, CNTF significantly increased mRNA and protein levels related to cell survival, such as Cx36, PAX4, and BCL-2, reduced caspase-3 activity, and islet cells apoptosis, suggesting that CNTF does not affect islet cell differentiation and, instead, acts as a survival factor reducing apoptosis by increasing the expression of the anti-apoptotic BCL-2 protein and decreasing caspase-3 activity.
    Journal of Endocrinology 11/2007; 195(1):157-65. · 4.06 Impact Factor
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    ABSTRACT: Biomedical research in which venom components are being investigated for their potential as novel therapeutic agents has emerged as an interesting option. Crotapotin, which is purified from the venom of the rattlesnake Crotalus durissus terrificus, has been described as an anti-inflammatory agent that acts on the innate arm of the immune response. Here we have demonstrated that intraperitoneal administration of crotapotin significantly reduces the severity of experimental autoimmune neuritis (EAN), an experimental model for Guillain-Barré syndrome. The reduction of the severity of the disease is associated with a reduction in the mononuclear cells infiltrating the sciatic nerve and a significant decrease in the lymphocyte proliferative response to neuritogenic peptide.
    Toxicon 04/2007; 49(3):299-305. · 2.92 Impact Factor

Publication Stats

424 Citations
101.06 Total Impact Points

Institutions

  • 2012
    • University of Brasília
      • Departamento de Biologia Celular (CEL)
      Brasília, Distrito Federal, Brazil
  • 2001–2012
    • University of Campinas
      • • Instituto de Biologia (IB)
      • • Faculty of Medical Sciences
      Campinas, Estado de Sao Paulo, Brazil
  • 2011
    • São Paulo State University
      • Departamento de Física e Biofísica
      São José do Rio Preto, Estado de Sao Paulo, Brazil