Methylene Blue Reduces Electroretinogram Distortion and Ganglion Cell Death in a Rat Model of Glaucoma.

Glaucoma is the second leading cause of blindness worldwide and is, in most cases, a consequence of elevated intraocular pressure (IOP), ultimately resulting in the death of retinal ganglion cells (RGCs). Current treatments are mostly focused on normalizing IOP, but we propose the additional use of neuroprotective agents, including methylene blue (MB), to block the loss of RGCs. Wistar rats were subjected to episcleral vein cauterization (EVC) in the left eye while the right eye was sham-operated.

A hypothermia mimetic molecule (zr17-2) reduces ganglion cell death, gliosis, and electroretinogram distortion in male rats subjected to perinatal asphyxia.

Perinatal asphyxia (PA) represents a major problem in perinatology and may cause visual losses, including blindness. We, and others, have shown that hypothermia prevents retinal symptoms associated to PA. In the present work, we evaluate whether a hypothermia mimetic small molecule, zr17-2, has similar effects in the context of PA.

A hypothermia mimetic molecule (zr17-2) reduces ganglion cell death and electroretinogram distortion in a rat model of intraorbital optic nerve crush (IONC).

Ocular and periocular traumatisms may result in loss of vision. Our previous work showed that therapeutic hypothermia prevents retinal damage caused by traumatic neuropathy. We also generated and characterized small molecules that elicit the beneficial effects of hypothermia at normal body temperature.

CB1 Cannabinoid Receptor is a Target for Neuroprotection in Light Induced Retinal Degeneration.

In the last few years, an increasing interest in the neuroprotective effect of cannabinoids has taken place. The aim of the present work was to study the effects of modulating cannabinoid receptor 1 (CB1) in the context of light induced retinal degeneration (LIRD), using an animal model that resembles many characteristics of human age-related macular degeneration (AMD) and other degenerative diseases of the outer retina. Sprague Dawley rats ( = 28) were intravitreally injected in the right eye with either a CB1 agonist (ACEA), or an antagonist (AM251).

Adenosine A2A Receptor: A New Neuroprotective Target in Light-Induced Retinal Degeneration.

Continuous illumination induces the degeneration of photoreceptors. This animal model of light-induced retinal degeneration resembles many characteristics of human degenerative diseases of the outer retina, such as age-related macular degeneration. This work aimed to evaluate the potential neuroprotective effect of the modulation of adenosine A2A receptor in the model of light-induced retinal degeneration.

Methylene Blue Prevents Retinal Damage Caused by Perinatal Asphyxia in the Rat.

Perinatal asphyxia (PA) is responsible for a large proportion of neonatal deaths and numerous neurological sequelae, including visual dysfunction and blindness. In PA, the retina is exposed to ischemia/reoxygenation, which results in nitric oxide (NO) overproduction and neurotoxicity. We hypothesized that methylene blue (MB), a guanylyl cyclase inhibitor, and free-radical scavenger currently used in the clinic, may block this pathway and prevent PA-induced retinal degeneration.

Statistical differences resulting from selection of stable reference genes after hypoxia and hypothermia in the neonatal rat brain.

Real-time reverse transcription PCR (qPCR) normalized to an internal reference gene (RG), is a frequently used method for quantifying gene expression changes in neuroscience. Although RG expression is assumed to be constant independent of physiological or experimental conditions, several studies have shown that commonly used RGs are not expressed stably. The use of unstable RGs has a profound effect on the conclusions drawn from studies on gene expression, and almost universally results in spurious estimation of target gene expression.

Structural organization, GABAergic and tyrosine hydroxylase expression in the striatum and globus pallidus of the South American plains vizcacha, Lagostomus maximus (Rodentia, Caviomorpha).

The striatum is an essential component of the basal ganglia that regulatessensory processing, motor, cognition, and behavior. Depending on the species, the striatum shows a unique structure called caudate-putamen as in mice, or its separation into two regions called caudate and lenticular nuclei, the latter formed by putamen and globus pallidus areas, as in primates. These structures have two compartments, striosome and matrix.

Hypothermia Prevents Retinal Damage Generated by Optic Nerve Trauma in the Rat.

Ocular and periocular traumatisms may result in loss of vision. Hypothermia provides a beneficial intervention for brain and heart conditions and, here, we study whether hypothermia can prevent retinal damage caused by traumatic neuropathy. Intraorbital optic nerve crush (IONC) or sham manipulation was applied to male rats.

Cold Shock Proteins Are Expressed in the Retina Following Exposure to Low Temperatures.

Hypothermia has been proposed as a therapeutic intervention for some retinal conditions, including ischemic insults. Cold exposure elevates expression of cold-shock proteins (CSP), including RNA-binding motif protein 3 (RBM3) and cold inducible RNA-binding protein (CIRP), but their presence in mammalian retina is so far unknown. Here we show the effects of hypothermia on the expression of these CSPs in retina-derived cell lines and in the retina of newborn and adult rats.

Methylene blue prevents retinal damage in an experimental model of ischemic proliferative retinopathy.

Perinatal asphyxia induces retinal lesions, generating ischemic proliferative retinopathy, which may result in blindness. Previously, we showed that the nitrergic system was involved in the physiopathology of perinatal asphyxia. Here we analyze the application of methylene blue, a well-known soluble guanylate cyclase inhibitor, as a therapeutic strategy to prevent retinopathy.

Psychiatric disorders in patients with psychogenic nonepileptic seizures and drug-resistant epilepsy: a study of an Argentine population.

Epidemiological data show that up to 20-30% of patients with psychogenic nonepileptic seizures (PNESs), resembling drug-resistant epilepsy (DRE), are referred to tertiary epilepsy centers. Furthermore, both disorders present high psychiatric comorbidity, and video-EEG is the gold standard to make differential diagnoses. In this study, we described and compared the clinical presentation and the frequency of psychiatric disorders codified in DSM IV in two groups of patients, one with PNESs and the other with DRE, admitted in a tertiary care epilepsy center of Buenos Aires, Argentina.

Hypothermia prevents gliosis and angiogenesis development in an experimental model of ischemic proliferative retinopathy.

Purpose: To develop a time course study of vascularization and glial response to perinatal asphyxia in hypoxic-ischemic animals, and to evaluate hypothermia as possible protective treatment.

Methods: We used retinas of 7-, 15-, 21-, and 30-day-old male Sprague-Dawley rats that were exposed to perinatal asphyxia at either 37°C (PA) or 15°C (HYP). Born to term animals were used as controls (CTL).

Epigenetic modification of liver mitochondrial DNA is associated with histological severity of nonalcoholic fatty liver disease.

Objective & Design: Nonalcoholic fatty liver disease (NAFLD) is a clinical condition that refers to progressive histological changes ranging from simple steatosis (SS) to nonalcoholic steatohepatitis (NASH). We evaluated the status of cytosine methylation (5mC) of liver mitochondrial DNA (mtDNA) in selected regions of the mtDNA genome, such as D-loop control region, and mitochondrially encoded NADH dehydrogenase 6 (MT-ND6) and cytochrome C oxidase I (MT-CO1), to contrast the hypothesis that epigenetic modifications play a role in the phenotypic switching from SS to NASH.

Methods: We studied liver biopsies obtained from patients with NAFLD in a case-control design; 45 patients and 18 near-normal liver-histology subjects.

Histological characterization of gonadotropin-releasing hormone (GnRH) in the hypothalamus of the South American plains vizcacha (Lagostomus maximus).

In contrast to most mammalian species, females of the South American plains vizcacha, Lagostomus maximus, show an extensive suppression of apoptosis-dependent follicular atresia, continuous folliculogenesis, and massive polyovulation. These unusual reproductive features pinpoint to an eventual peculiar modulation of the hypothalamo-hypophyseal-gonadal axis through its main regulator, the gonadotropin-releasing hormone (GnRH). We explored the hypothalamic histological landscape and cellular and subcellular localization of GnRH in adult non-pregnant L.

Hypothermia prevents nitric oxide system changes in retina induced by severe perinatal asphyxia.

One-third of asphyctic neonates develop long-term neurological injuries, including several degrees of ischemic proliferative retinopathy (IPR) such as retinopathy of prematurity (ROP). Given that the retina is altered by perinatal asphyxia, our aim was to study the effects of nitric oxide (NO) in the retina in order to analyze its impact on the retinal injury. Application of hypothermia was evaluated as preventive treatment.

Changes in neostriatal and hippocampal synaptic densities in perinatal asphyctic male and female young rats: Role of hypothermia.

Perinatal asphyxia (PA) may cause long-term neurological and psychiatric diseases. We evaluated, by ethanolic phosphotungstic acid (E-PTA) staining, whether PA affects postsynaptic densities (PSDs), ultrastructure of neostriatum and hippocampus of 45-day-old post-PA male and female rats. PA was induced by placing the uterine horns containing the fetuses in a 37°C bath for 10, 15, 19 and 20 min and a 15°C bath for 20 min (hypothermia).

Hypothermia prevents the development of ischemic proliferative retinopathy induced by severe perinatal asphyxia.

Obstetric complications, such as perinatal asphyxia, may cause retinal injuries as retinopathy of prematurity (ROP), a type of ischemic proliferative retinopathy. Up to date there are no appropriate experimental models for studying the long-term sequels of this disease. In the present work, we present an experimental model of perinatal asphyxia which shows structural and ultrastructural retinal alterations at the most inner layers of the retina, such as neurodegeneration, development of neoformed vessels and glial reaction, which are compatible with the histopathological description of ROP.

Clostridium perfringens epsilon toxin increases the small intestinal permeability in mice and rats.

Epsilon toxin is a potent neurotoxin produced by Clostridium perfringens types B and D, an anaerobic bacterium that causes enterotoxaemia in ruminants. In the affected animal, it causes oedema of the lungs and brain by damaging the endothelial cells, inducing physiological and morphological changes. Although it is believed to compromise the intestinal barrier, thus entering the gut vasculature, little is known about the mechanism underlying this process.

Nitric oxide system alteration at spinal cord as a result of perinatal asphyxia is involved in behavioral disabilities: hypothermia as preventive treatment.

Perinatal asphyxia (PA) is able to induce sequelae such as spinal spasticity. Previously, we demonstrated hypothermia as a neuroprotective treatment against cell degeneration triggered by increased nitric oxide (NO) release. Because spinal motoneurons are implicated in spasticity, our aim was to analyze the involvement of NO system at cervical and lumbar motoneurons after PA as well as the application of hypothermia as treatment.

Intracerebroventricular administration of Shiga toxin type 2 induces striatal neuronal death and glial alterations: an ultrastructural study.

Shiga toxin (Stx) from enterohemorrhagic Escherichia coli (STEC) is the main cause of hemorrhagic colitis which may derive to hemolytic-uremic syndrome (HUS). HUS is characterized by acute renal failure, thrombocytopenia and microangiopathic hemolytic anemia. Mortality in the acute stage has been lower than 5% of total affected argentine children with endemic HUS.

Long term production of reactive oxygen species during perinatal asphyxia in the rat central nervous system: effects of hypothermia.

The formation of oxygen-derived free radicals in hypoxic and ischemic/reperfused brains has been proposed as an important step that links brain injury to neuronal death. Previously, we have demonstrated that reactive oxygen species (ROS) production was significantly increased in rat neostriatum during acute perinatal asphyxia (PA) in pups. In this article, we have studied the time course of ROS production in the neostriatum and neocortex of adult rats subjected to PA using electron spin resonance spectrometry (ESR) in order to record ROS production.