Patterns of fos activation in rat raphe nuclei during feeding behavior

To analyze the differential recruitment of the raphe nuclei during different phases of feeding behavior, rats were subjected to a food restriction schedule (food for 2 h/day, during 15 days). The animals were submitted to different feeding conditions, constituting the experimental groups: search for food (MFS), food ingestion (MFI), satiety (MFSa) and food restriction control (MFC). A baseline condition (BC) group was included as further control. The MFI and MFC groups, which presented greater autonomic and somatic activation, had more FOS-immunoreactive (FOS-IR) neurons. The MFI group presented more labeled cells in the linear (LRN) and dorsal (DRN) nuclei; the MFC group showed more labeling in the median (MRN), pontine (PRN), magnus (NRM) and obscurus (NRO) nuclei; and the MFSa group had more labeled cells in the pallidus (NRP). The BC exhibited the lowest number of reactive cells. The PRN presented the highest percentage of activation in the raphe while the DRN the lowest. Additional experiments revealed few double-labeled (FOS-IR+ 5-HT-IR) cells within the raphe nuclei in the MFI group, suggesting little serotonergic activation in the raphe during food ingestion. These findings suggest a differential recruitment of raphe nuclei during various phases of feeding behavior. Such findings may reflect changes in behavioral state (e.g., food-induced arousal versus sleep) that lead to greater motor activation, and consequently increased FOS expression. While these data are consistent with the idea that the raphe system acts as gain setter for autonomic and somatic activities, the functional complexity of the raphe is not completely understood. (c) 2008 Elsevier B.V. All rights reserved

The effects of acute and chronic administration of phosphatidylserine on cell proliferation and survival in the dentate gyms of adult and middle-aged rats

Phosphatidylserine (PS) is an acidic phospholipid that is widely used as an alternative and/or complementary treatment of cognitive impairments. We hypothesize that these changes may be attributable, at least in part, to alterations in hippocampal neurogenesis. The aim of the present study was to investigate the effects of acute and chronic PS administration on hippocampal cell proliferation and survival in adult (5 months old) and middle-aged (12 months old) male Wistar rats. PS was injected daily (50 mg/kg, i.p.) during 7 days (acute experiment) or 21 days (chronic experiment). To label newly generated cells, rats received a single BrdU injection (200 mg/kg, i.p.) one day before PS treatment. The object recognition test was performed, and the rats were perfused. The brains were removed and processed with immunohistochemistry techniques for Ki-67 (cell proliferation) and BrdU (cell survival). The acute and chronic regimens were unable to promote cognitive improvement in either age group in the object recognition test. The analysis of cell proliferation showed a significant increase in the number of Ki-67-positive cells after acute and chronic PS administration in both age groups. The analysis of cell survival showed that acute and chronic PS administration increased the number of BrdU-positive cells only in adult animals.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Ethanol intake-induced apoptosis in glial cells and axonal disorders in the cerebellar white matter of UChA rats (voluntary ethanol consumers)

Ethanol intake may cause alterations in cellular metabolism altering motricity, learning and cognition. The cerebellum is one of the most susceptible organs to ethanol-related disorders during development, and is associated with oxidative stress-induced apoptosis being crucial for pathogenic consequences. The UChA variety is a special strain of Wistar rat genetically selected and represents a rare model for the studies related to genetic, biochemical, physiological, nutritional, and pharmacological effects of ethanol. We evaluated the structure and apoptosis in the cerebellar white matter of UChA rats. There were two groups of 09 rats: a control group that did not consume ethanol, and an experimental group of UChA rats that consumed ethanol at 10% (v/v) (<2 g ethanol/kg body weight/day). At 120 days old, rats were anaesthetized followed by decapitation, and their cerebella were collected and fixed. Cerebellar sections were subjected to immunohistochemistry for Caspase-3 and XIAP and transmission electron microscopy (TEM). The UChA group showed more glial cells immunoreactive for caspase-3 and less for XIAP than control group. Alcohol consumption affected myelin integrity. Severe ultrastructural damages in UChA group were observed such as disruption of the myelin sheath, disorganization and deformation of its components, and an increase in the interaxonal spaces. In conclusion, our data demonstrated that ethanol induced apoptosis in the glial cells and promoted an intense change in the myelin sheath of UChA rats, which may cause functional disorders.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Taurine Neuroprotection and Neurogenesis Effect in Chronic Ethanol-Induced Rats

Taurine (2-aminoethanesulfonic acid) is a non-protein β-amino acid essential for cellular homeostasis, with antioxidant, anti-inflammatory, and cytoprotective properties that are crucial for life maintenance. This study aimed to evaluate the effects of taurine administration on hippocampal neurogenesis, neuronal preservation, or reverse damage in rats exposed to forced ethanol consumption in an animal model. Wistar rats were treated with ethanol (EtOH) for a 28-day period (5% in the 1st week, 10% in the 2nd week, and 20% in the 3rd and 4th weeks). Two taurine treatment protocols (300 mg/kg i.p.) were implemented: one during ethanol consumption to analyze neuroprotection, and another after ethanol consumption to assess the reversal of ethanol-induced damage. Overall, the results demonstrated that taurine treatment was effective in protecting against deficits induced by ethanol consumption in the dentate gyrus. The EtOH+TAU group showed a significant increase in cell proliferation (145.8%) and cell survival (54.0%) compared to the EtOH+Sal group. The results also indicated similar effects regarding the reversal of ethanol-induced damage 28 days after the cessation of ethanol consumption. The EtOH+TAU group exhibited a significant increase (41.3%) in the number of DCX-immunoreactive cells compared to the EtOH+Sal group. However, this amino acid did not induce neurogenesis in the tissues of healthy rats, implying that its activity may be contingent upon post-injury stimuli

Apoptosis of Purkinje and Granular Cells of the Cerebellum Following Chronic Ethanol Intake

Ethanol alters motricity, learning, cognition, and cellular metabolism in the cerebellum. We evaluated the effect of ethanol on apoptosis in Golgi, Purkinje, and granule cells of the cerebellum in adult rats. There were two groups of 20 rats: a control group that did not consume ethanol and an experimental group of UChA rats that consumed ethanol at 10 % (<2 g ethanol/kg body weight/day). At 120 days old, rats were anesthetized and decapitated, and their cerebella were collected and fixed. Cerebellar sections were subjected to immunohistochemistry for terminal deoxynucleotide transferase dUTP nick end labeling (TUNEL), caspase-3, X-linked inhibitor of apoptosis protein (XIAP), and insulin-like growth factor 1-receptor (IGF-1R); real-time PCR (RT-PCR) to determine caspase-3, XIAP, and IGF-1R gene expression; and transmission electron microscopy (TEM). We identified fragmentation of DNA and an increase in caspase-3 protein and XIAP in Purkinje cells, whereas granule cells exhibited increased caspase-3 and XIAP. IGF-1R expression was unchanged. There was no significant difference in gene expression of caspase-3, XIAP, and IGF-1R. There were an increase in lipid droplets, a reduction in the cellular cytoplasm in electrondense nuclei, and changes in the myelin sheath in the cerebellar cortex. In conclusion, our data demonstrated that ethanol induced apoptosis in the Purkinje and granule cells of the cerebellum of adult UChA rats.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Impact of neonatal anoxia on adult rat hippocampal volume, neurogenesis and behavior

Neonates that suffer oxygen deprivation during birth can have long lasting cognitive deficits, such as memory and learning impairments. Hippocampus, one of the main structures that participate in memory and learning processes, is a plastic and dynamic structure that conserves during life span the property of generating new cells which can become neurons, the so-called neurogenesis. The present study investigated whether a model of rat neonatal anoxia, that causes only respiratory distress, is able to alter the hippocampal volume, the neurogenesis rate and has functional implications in adult life. MRI analysis revealed significant hippocampal volume decrease in adult rats who had experienced neonatal anoxia compared to control animals for rostra!, caudal and total hippocampus. In addition, these animals also had 55.7% decrease of double-labelled cells to BrdU and NeuN, reflecting a decrease in neurogenesis rate. Finally, behavioral analysis indicated that neonatal anoxia resulted in disruption of spatial working memory, similar to human condition, accompanied by an anxiogenic effect. The observed behavioral alterations caused by oxygen deprivation at birth might represent an outcome of the decreased hippocampal neurogenesis and volume, evidenced by immunohistochemistry and MRI analysis. Therefore, based on current findings we propose this model as suitable to explore new therapeutic approaches. (C) 2015 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Departamento de Anatomia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, BrazilNúcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Santo André, BrazilDepartamento de Fisiologia Geral, Instituto de Biociências, Universidade de São Paulo, São Paulo, BrazilDepartamento de Fisiologia, Universidade Federal de São Paulo, São Paulo, BrazilDepartamento de Morfologia e Patologia, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Carlos, BrazilDepartamento de Fisiologia, Universidade Federal de São Paulo, São Paulo, BrazilFAPESP: 2010/01488-9FAPESP: 2009/51557-0Web of Scienc

Impact of neonatal anoxia and hypothermic treatment on development and memory of rats

Therapeutic hypothermia (TH) is well established as a standard treatment for term and near-term infants. However, therapeutic effects of hypothermia following neonatal anoxia in very premature babies remains inconclusive. The present rodent model of preterm neonatal anoxia has been shown to alter developmental milestones and hippocampal neurogenesis, and to disrupt spatial learning and memory in adulthood. These effects seem to be reduced by post-insult hypothermia. Epigenetic-related mechanisms have been postulated as valuable tools for developing new therapies. Dentate gyrus neurogenesis is regulated by epigenetic factors. This study evaluated whether TH effects in a rodent model of preterm oxygen deprivation are based on epigenetic alterations. The effects of TH on both developmental features (somatic growth, maturation of physical characteristics and early neurological reflexes) and performance of behavioral tasks at adulthood (spatial reference and working memory, and fear conditioning) were investigated in association with the possible involvement of the epigenetic operator Enhancer of zeste homolog 2 (Ezh2), possibly related to long-lasting effects on hippocampal neurogenesis. Results showed that TH reduced both anoxia-induced hippocampal neurodegeneration and anoxiainduced impairments on risk assessment behavior, acquisition of spatial memory, and extinction of auditory and contextual fear conditioning. In contrast, TH did not prevent developmental alterations caused by neonatal anoxia and did not restore hippocampal neurogenesis or cause changes in EZH2 levels. In conclusion, despite the beneficial effects of TH in hippocampal neurodegeneration and in reversing disruption of performance of behavioral tasks following oxygen deprivation in prematurity, these effects seem not related to developmental alterations and hippocampal neurogenesis and, apparently, is not caused by Ezh2-mediated epigenetic alteration.Fil: Matsuda, Victor Daniel Vasquez. Universidade de Sao Paulo; BrasilFil: Bustelo Tejada, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; Argentina. Universiteit Maastricht. Faculty of Health Medicine and Life Sciences; Países Bajos. Universidad Católica de Cuyo. Facultad de Ciencias Médicas. Instituto de Investigación en Ciencias Biomédicas; Argentina. Universidad Federal do Abc; BrasilFil: Motta Teixeira, Lívia Clemente. Universidade de Sao Paulo; BrasilFil: Ikebara, Juliane Midori. Universidad Federal do Abc; BrasilFil: Cardoso, Débora Sterzeck. Universidad Federal do Abc; BrasilFil: Machado Nils, Aline Vilar. Universidade de Sao Paulo; BrasilFil: Lee, Vitor Yonamine. Universidade de Sao Paulo; BrasilFil: Diccini, Isabelle. Universidade de Sao Paulo; BrasilFil: Arruda, Bruna Petrucelli. Universidade de Sao Paulo; Brasil. Universidad Federal do Abc; BrasilFil: Martins, Pamela Pinheiro. Universidad Federal do Abc; BrasilFil: Dias, Natália Myuki Morales. Universidad Federal do Abc; BrasilFil: Tessarotto, Rafaella Pinto. Universidad Federal do Abc; BrasilFil: Raeisossadati, Reza. Universidad Federal do Abc; BrasilFil: Bruno, Martin. Universidad Católica de Cuyo. Facultad de Ciencias Médicas. Instituto de Investigación en Ciencias Biomédicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; ArgentinaFil: Takase, Luiz Fernando. Universidade Federal do São Carlos; BrasilFil: Kihara, Alexandre Hiroaki. Universidad Federal do Abc; BrasilFil: Nogueira, Maria Inês. Universidade de Sao Paulo; BrasilFil: Xavier, Gilberto Fernando. Universidade de Sao Paulo; BrasilFil: Takada, Silvia Honda. Universidad Federal do Abc; Brasi

Current practice in the management of ocular toxoplasmosis

Background Ocular toxoplasmosis is common across all regions of the world. Understanding of the epidemiology and approach to diagnosis and treatment have evolved recently. In November 2020, an international group of uveitis-specialised ophthalmologists formed the International Ocular Toxoplasmosis Study Group to define current practice. Methods 192 Study Group members from 48 countries completed a 36-item survey on clinical features, use of investigations, indications for treatment, systemic and intravitreal treatment with antiparasitic drugs and corticosteroids, and approach to follow-up and preventive therapy. Results For 77.1% of members, unilateral retinochoroiditis adjacent to a pigmented scar accounted for over 60% of presentations, but diverse atypical presentations were also reported. Common complications included persistent vitreous opacities, epiretinal membrane, cataract, and ocular hypertension or glaucoma. Most members used clinical examination with (56.8%) or without (35.9%) serology to diagnose typical disease but relied on intraocular fluid testing-usually PCR-in atypical cases (68.8%). 66.1% of members treated all non-pregnant patients, while 33.9% treated selected patients. Oral trimethoprim-sulfamethoxazole was first-line therapy for 66.7% of members, and 60.9% had experience using intravitreal clindamycin. Corticosteroid drugs were administered systemically by 97.4%; 24.7% also injected corticosteroid intravitreally, almost always in combination with an antimicrobial drug (72.3%). The majority of members followed up all (60.4%) or selected (35.9%) patients after resolution of acute disease, and prophylaxis against recurrence with trimethoprim-sulfamethoxazole was prescribed to selected patients by 69.8%. Conclusion Our report presents a current management approach for ocular toxoplasmosis, as practised by a large international group of uveitis-specialised ophthalmologists

Ticagrelor in patients with diabetes and stable coronary artery disease with a history of previous percutaneous coronary intervention (THEMIS-PCI) : a phase 3, placebo-controlled, randomised trial

Background: Patients with stable coronary artery disease and diabetes with previous percutaneous coronary intervention (PCI), particularly those with previous stenting, are at high risk of ischaemic events. These patients are generally treated with aspirin. In this trial, we aimed to investigate if these patients would benefit from treatment with aspirin plus ticagrelor. Methods: The Effect of Ticagrelor on Health Outcomes in diabEtes Mellitus patients Intervention Study (THEMIS) was a phase 3 randomised, double-blinded, placebo-controlled trial, done in 1315 sites in 42 countries. Patients were eligible if 50 years or older, with type 2 diabetes, receiving anti-hyperglycaemic drugs for at least 6 months, with stable coronary artery disease, and one of three other mutually non-exclusive criteria: a history of previous PCI or of coronary artery bypass grafting, or documentation of angiographic stenosis of 50% or more in at least one coronary artery. Eligible patients were randomly assigned (1:1) to either ticagrelor or placebo, by use of an interactive voice-response or web-response system. The THEMIS-PCI trial comprised a prespecified subgroup of patients with previous PCI. The primary efficacy outcome was a composite of cardiovascular death, myocardial infarction, or stroke (measured in the intention-to-treat population). Findings: Between Feb 17, 2014, and May 24, 2016, 11 154 patients (58% of the overall THEMIS trial) with a history of previous PCI were enrolled in the THEMIS-PCI trial. Median follow-up was 3·3 years (IQR 2·8–3·8). In the previous PCI group, fewer patients receiving ticagrelor had a primary efficacy outcome event than in the placebo group (404 [7·3%] of 5558 vs 480 [8·6%] of 5596; HR 0·85 [95% CI 0·74–0·97], p=0·013). The same effect was not observed in patients without PCI (p=0·76, p interaction=0·16). The proportion of patients with cardiovascular death was similar in both treatment groups (174 [3·1%] with ticagrelor vs 183 (3·3%) with placebo; HR 0·96 [95% CI 0·78–1·18], p=0·68), as well as all-cause death (282 [5·1%] vs 323 [5·8%]; 0·88 [0·75–1·03], p=0·11). TIMI major bleeding occurred in 111 (2·0%) of 5536 patients receiving ticagrelor and 62 (1·1%) of 5564 patients receiving placebo (HR 2·03 [95% CI 1·48–2·76], p<0·0001), and fatal bleeding in 6 (0·1%) of 5536 patients with ticagrelor and 6 (0·1%) of 5564 with placebo (1·13 [0·36–3·50], p=0·83). Intracranial haemorrhage occurred in 33 (0·6%) and 31 (0·6%) patients (1·21 [0·74–1·97], p=0·45). Ticagrelor improved net clinical benefit: 519/5558 (9·3%) versus 617/5596 (11·0%), HR=0·85, 95% CI 0·75–0·95, p=0·005, in contrast to patients without PCI where it did not, p interaction=0·012. Benefit was present irrespective of time from most recent PCI. Interpretation: In patients with diabetes, stable coronary artery disease, and previous PCI, ticagrelor added to aspirin reduced cardiovascular death, myocardial infarction, and stroke, although with increased major bleeding. In that large, easily identified population, ticagrelor provided a favourable net clinical benefit (more than in patients without history of PCI). This effect shows that long-term therapy with ticagrelor in addition to aspirin should be considered in patients with diabetes and a history of PCI who have tolerated antiplatelet therapy, have high ischaemic risk, and low bleeding risk