Exposure to Ozone Downregulates Bcl-2 and Increases Executing Caspases-3 and -8 in the Hippocampus, Frontal Cortex, and Cerebellum of Rats.

Introduction Ozone (O3) is one of the most prevalent atmospheric pollutants, arising from a photochemical reaction between volatile organic compounds (VOC), nitrogen oxides (NOx), and sunlight. O3 triggers oxidative stress, resulting in lipid oxidation, inflammation, alterations in metabolic and cellular signaling, and potentially initiating cell death in vulnerable brain regions. Inflammation and oxidative stress are recognized for their ability to induce cell death, primarily through the apoptosis pathway, involving various proteins that participate in this process via two pathways: intrinsic and extrinsic. Objective This study aims to identify the expression of pro-apoptotic proteins and Bcl-2 in the frontal cortex, cerebellum, and hippocampus of rats exposed to O3 acutely. Methods Two groups of 20 Wistar rodents (250-300 g) were established. The control group (n=10) was exposed to unrestricted polluted air for 12 hours, while the experimental group (n=10) was exposed to 1 ppm of O3. After exposure, the animals were sacrificed for immunofluorescence and Western blot analysis. Using a t-test, the arbitrary units of pro-apoptotic proteins and Bcl-2 were compared between the two groups. Results Significant increases in caspase-8 and caspase-3 activation were found in the O3-exposed group compared to the control group, specifically in the frontal cortex, cerebellum, and hippocampus. Additionally, notable changes in Bcl-2 expression were observed in these brain regions. The TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) assay further indicated significant differences in immunopositivity between the groups in the same areas. However, intrinsic apoptotic proteins such as Bax, VDAC1, and cytochrome-c did not show significant differences between the groups within these structures. Western blot analyses aligned with the immunofluorescence results, showing statistically significant concentrations of caspase-8 in the cerebellum, caspase-3 in the hippocampus, and Bcl-2 in the frontal cortex in the O3 exposed group. Conversely, proteins like Bax, cytochrome-c, and VDAC1 did not exhibit significant differences in all analyzed structures. Conclusions This study demonstrates that acute exposure to 1 ppm of ozone can trigger neuronal apoptosis in the frontal cortex, hippocampus, and cerebellum of rats, primarily through the activation of the extrinsic apoptosis pathway via caspase-8 and caspase-3. Additionally, it causes a reduction in Bcl-2 expression, an essential antiapoptotic protein. Despite not observing the activation of intrinsic pathway proteins like BAX, VDAC, or cytochrome-c, the study suggests that chronic O3 exposure might promote cell death by activating this pathway, requiring further long-term research.

Rats in Epilepsy Research: A Bibliometric Analysis of Citations Between 1969 and 2020 on Experimental Models in Epilepsy.

Epilepsy stands as a prominent neurological disorder, affecting a substantial number of individuals who, unfortunately, do not respond to conventional antiepileptic medications. To unravel the intricate mechanisms underlying epileptic seizures and explore potential therapeutic avenues, researchers have turned to animal models. Among these models, rats have emerged as one of the cornerstones of epilepsy research. This bibliometric analysis embarks on the crucial task of delving into the role of rat models in deciphering the mysteries of epileptic seizures and, notably, pinpointing the most prevalent models in use. Our study harnessed Scopus' citation tracking feature to review a range of research papers dating from 1969 to 2020, all dedicated to the exploration of epileptic seizures in rats. The citations that emerged from this rigorous process were subjected to thematic coding, primarily centered around the specific epileptic animal models employed, and subsequently, comprehensive descriptive statistics were computed. In this effort, we found a total of 1,318 publications that explore the world of rat studies, accumulating a substantial citation count of 44,824 references. This analysis illuminated the invaluable role that research employing rat models has played in shaping our current clinical understanding of epileptic seizures. Notably, several models have emerged as predominant forces in this field, including those induced by pilocarpine, pentylenetetrazole (PTZ), kainic acid (KA), electric kindling, and electroshock. This bibliometric exploration serves as a resounding reminder of the pivotal position that rat models occupy in advancing our comprehension of epilepsy. These findings resonate strongly, underscoring the continued importance of directing research and development funding toward this debilitating disorder, with the ultimate aim of maximizing the benefits for the patients grappling with this condition. The potential to revolutionize our approach to epilepsy and enhance the quality of life for those affected remains a beacon of hope, illuminated by the contributions of these tireless researchers and their trusty rat companions.

The Role of the Vagus Nerve in the Microbiome and Digestive System in Relation to Epilepsy.

The Enteric Nervous System (ENS) is described as a division of the Peripheral Nervous System (PNS), located within the gut wall and it is formed by two main plexuses: the myenteric plexus (Auerbach's) and the submucosal plexus (Meissner's). The contribution of the ENS to the pathophysiology of various neurological diseases such as Parkinson's or Alzheimer's disease has been described in the literature, while some other studies have found a connection between epilepsy and the gastrointestinal tract. The above could be explained by cholinergic neurons and neurotransmission systems in the myenteric and submucosal plexuses, regulating the vagal excitability effect. It is also understandable, as the discharges arising in the amygdala are transmitted to the intestine through projections the dorsal motor nucleus of the vagus, giving rise to efferent fibers that stimulate the gastrointestinal tract and consequently the symptoms at this level. Therefore, this review's main objective is to argue in favor of the existing relationship of the ENS with the Central Nervous System (CNS) as a facilitator of epileptogenic or ictogenic mechanisms. The gut microbiota also participates in this interaction; however, it depends on many individual factors of each human being. The link between the ENS and the CNS is a poorly studied epileptogenic site with a big impact on one of the most prevalent neurological conditions such as epilepsy.

Repurposing Simvastatin in Parkinson's Disease Model: Protection Is throughout Modulation of the Neuro-Inflammatory Response in the Substantia nigra.

Parkinson's disease is a neurodegenerative disorder characterized by oxidative stress and immune activation in the nigro-striatal pathway. Simvastatin regulates cholesterol metabolism and protects from atherosclerosis disease. Simvastatin-tween 80 was administered 7 days before sterotaxic intrastriatal administration of MPP+ (1-methyl-4-phenylpyridine) in rats. Fluorescent lipidic product formation, dopamine levels, and circling behavior were considered damage markers. Twenty-four hours and six days after, the animal group lesioned with MPP+ showed significant damage in relation to the control group. Animals pretreated with simvastatin significantly reduced the MPP+-induced damage compared to the MPP+ treated group. As apoptosis promotes neuroinflammation and neuronal degeneration in Parkinson's disease, and since there is not currently a proteomic map of the nigro-striatum of rats and assuming a high homology among the identified proteins in other rat tissues, we based the search for rat protein homologs related to the establishment of inflammation response. We demonstrate that most proteins related to inflammation decreased in the simvastatin-treated rats. Furthermore, differential expression of antioxidant enzymes in striated tissue of rat brains was found in response to simvastatin. These results suggest that simvastatin could prevent striatal MPP+-induced damage and, for the first time, suggest that the molecular mechanisms involved in this have a protective effect.

The Participation of Ca2+ Channels in Epilepsy: A Bibliometric Analysis of the Scientific Literature in Latin America.

BACKGROUND: Bibliometric analysis allows us to quantify and evaluate scientific activity, and it has become increasingly important in all areas of scientific literature. Thanks to these analyses, we can infer where science should put greater efforts into elucidating the underlying mechanisms of diseases that have yet to be fully described or investigated. OBJECTIVE: This paper delves into published articles related to the involvement of calcium (Ca2+) channels in epilepsy, which is a condition with a high prevalence in Latin America. METHODS: We followed the scientific publication on SCOPUS and analyzed the impact of publications from Latin America in the field of epilepsy and the study of Ca2+ channels. We identified the countries with the largest number of publications and found that 68% of them were experimental (animal models), while 32% were clinical. We also identified the main journals, growth over time, and citation numbers. RESULTS: We found a total of 226 works produced by Latin American countries from 1976 to 2022. The countries that have contributed the most to the topic are Brazil, Mexico, and Argentina, with occasional collaborations between them to make contributions to the study of epilepsy and Ca2+ channels. Additionally, we found that the journal with the most citations is Nature Genetics. CONCLUSION: The number of authors per article ranges from 1 to 242, and neuroscience journals are the preferred target for researchers, with a predilection for publishing original articles, although 26% of the publications are review articles.

Molecular and Genetic Mechanisms of Neurotoxicity During Anti-seizure Medications Use.

Abstract: Epilepsy is a multifactorial pathology that has allowed the development of various drugs aiming to combat it. This effort was formally initiated in the 1940s when phenytoin began to be used. It eventually turned out to be a drug with great anticonvulsant efficacy. At present, several potentially good new generation anti-seizure medications (ASMs) have been developed. Most of them present more tolerability and less toxic effects. However, they continue to have adverse effects at different levels. In addition, some seizures are difficult to treat with ASMs, representing 30% of the total cases of people who suffer from epilepsy. This review aims to explore the genetic and molecular mechanisms of ASMs neurotoxicity, proposing the study of damage caused by epileptic seizures, in addition to the deterioration generated by anti-seizure drug administration within the central nervous system. It is beyond question that there is a need to develop drugs that lower the lower the risk of secondary and toxic effects of ASMs. Simultaneously, we must find strategies that produce fewer harmful interactions and more health benefits when taking anti-seizure drugs.

Molecular and Genetic Mechanisms of Neurotoxicity During Anti-seizure Medications Use

ABSTRACT Epilepsy is a multifactorial pathology that has allowed the development of various drugs aiming to combat it. This effort was formally initiated in the 1940s when phenytoin began to be used. It eventually turned out to be a drug with great anticonvulsant efficacy. At present, several potentially good new generation anti-seizure medications (ASMs) have been developed. Most of them present more tolerability and less toxic effects. However, they continue to have adverse effects at different levels. In addition, some seizures are difficult to treat with ASMs, representing 30% of the total cases of people who suffer from epilepsy. This review aims to explore the genetic and molecular mechanisms of ASMs neurotoxicity, proposing the study of damage caused by epileptic seizures, in addition to the deterioration generated by anti-seizure drug administration within the central nervous system. It is beyond question that there is a need to develop drugs that lower the lower the risk of secondary and toxic effects of ASMs. Simultaneously, we must find strategies that produce fewer harmful interactions and more health benefits when taking anti-seizure drugs.

Caloric restriction: Anti-inflammatory and antioxidant mechanisms against epileptic seizures.

Caloric restriction (CR) possesses different cellular mechanisms. Though there are still gaps in the literature regarding its plausible beneficial effects, the suggestion that this alternative therapy can improve the inflammatory and antioxidant response to control epileptic seizures is explored throughout this study. Epilepsy is the second most prevalent neurodegenerative disease in the world. However, the appropriate mechanisms for it to be fully controlled are still unknown. Neuroinflammation and oxidative stress promote epileptic seizures' appearance and might even aggravate them. There is growing evidence that caloric restriction has extensive anti-inflammatory and antioxidant properties. For instance, nuclear factor erythroid 2-related factor 2 (Nrf2) and all-trans retinoic acid (ATRA) have been proposed to induce antioxidant processes and ulteriorly improve the disease progression. Caloric restriction can be an option for those patients with refractory epilepsy since it allows for anti-inflammatory and antioxidant properties to evolve within the brain areas involved.

The short form of the SUR1 and its functional implications in the damaged brain.

Sulfonylurea receptor (SUR) belongs to the adenosine 5'-triphosphate (ATP)-binding cassette (ABC) transporter family; however, SUR is associated with ion channels and acts as a regulatory subunit determining the opening or closing of the pore. Abcc8 and Abcc9 genes code for the proteins SUR1 and SUR2, respectively. The SUR1 transcript encodes a protein of 1582 amino acids with a mass around 140-177 kDa expressed in the pancreas, brain, heart, and other tissues. It is well known that SUR1 assembles with Kir6.2 and TRPM4 to establish KATP channels and non-selective cation channels, respectively. Abbc8 and 9 are alternatively spliced, and the resulting transcripts encode different isoforms of SUR1 and SUR2, which have been detected by different experimental strategies. Interestingly, the use of binding assays to sulfonylureas and Western blotting has allowed the detection of shorter forms of SUR (~65 kDa). Identity of the SUR1 variants has not been clarified, and some authors have suggested that the shorter forms are unspecific. However, immunoprecipitation assays have shown that SUR2 short forms are part of a functional channel even coexisting with the typical forms of the receptor in the heart. This evidence confirms that the structure of the short forms of the SURs is fully functional and does not lose the ability to interact with the channels. Since structural changes in short forms of SUR modify its affinity to ATP, regulation of its expression might represent an advantage in pathologies where ATP concentrations decrease and a therapeutic target to induce neuroprotection. Remarkably, the expression of SUR1 variants might be induced by conditions associated to the decrease of energetic substrates in the brain (e.g. during stroke and epilepsy). In this review, we want to contribute to the knowledge of SUR1 complexity by analyzing evidence that shows the existence of short SUR1 variants and its possible implications in brain function.

Clothianidin and Thiacloprid Mixture Administration Induces Degenerative Damage in the Dentate Gyrus and Alteration in Short-Term Memory in Rats.

Neonicotinoids are pesticides that act as agonists of nicotinic receptors for acetylcholine in insects' central nervous system (CNS). Chronic exposure to neonicotinoids in humans is related to autism, memory loss, and finger tremor. In this article, we evaluate the effect of subchronic oral administration of two neonicotinoids in the same mixture: clothianidin and thiacloprid. Decreasing doses of both pesticides were administered to rats starting from the lethal dose 50 (LD50) reported by the manufacturer. Our results indicate that the administration of three doses of decreasing amounts of LD50 (5/10, 4/10, and 3/10 LD50) resulted in 100% death in all cases. Ten administration times of 2/10 LD50 of the mixture caused only 20% of death cases after twenty-seven days, which was determined as a subchronic administration scheme. The animals administered 2/10 LD50 showed behavioral alterations after the first and second administration. Electrographic studies showed abnormal discharge patterns in the CNS. 72 h after the tenth dose, learning and memory tests were performed in the Morris water maze. Our results revealed significant decreases in permanence at the quadrant and the number of crosses (P=0.0447, P=0.0193, respectively), which represent alterations in the short-term memory test, but there were no significant changes in a long-term memory test. Likewise, the brains of these animals showed tissue architecture loss, nucleosomal retraction, and a significant increase in the pycnosis of the granular neurons of the dentate gyrus analyzed at 72 h after the last dose (P=0.0125). Toxic effects and cognitive deterioration that have been found in communities living near contaminated areas are probably related to the agricultural use of neonicotinoids.

Antiepileptogenic Effect of Retinoic Acid.

Retinoic acid, a metabolite of vitamin A, acts through either genomic or nongenomic actions. The genomic action of retinoids exerts effects on gene transcription through interaction with retinoid receptors such as retinoic acid receptors (RARα, ß, and γ) and retinoid X receptors (RXRα, ß, and γ) that are primarily concentrated in the amygdala, pre-frontal cortex, and hippocampal areas in the brain. In response to retinoid binding, RAR/RXR heterodimers undergo major conformational changes and orchestrate the transcription of specific gene networks. Previous experimental studies have reported that retinoic acid exerts an antiepileptogenic effect through diverse mechanisms, including the modulation of gap junctions, neurotransmitters, long-term potentiation, calcium channels and some genes. To our knowledge, there are no previous or current clinical trials evaluating the use of retinoic acid for seizure control.

Characterization of the antiapoptotic effect of copper sulfate on striatal and midbrain damage induced by MPP+ in rats.

1-Methyl-4-phenylpyridinium ion (MPP+)-induced neurotoxicity produces cellular damage resembling that encountered in Parkinson's disease. The mechanisms of cellular death after MPP+ include the participation of oxidative stress in the loss of dopaminergic neurons. Among the mechanisms of defense against oxidative stress, several copper-dependent proteins have been implicated: Cu/Zn-SOD, ceruloplasmin, and metallothionein. Another important mechanism of damage, is MPP + interference with mitochondrial respiration. Both, oxidative stress and inhibition of mitochondrial respiration may trigger apoptosis in the neurons after MPP+. The aim of the present study was to characterize the time-course of apoptosis induced by MPP+ to determine if copper sulfate pretreatment is able to prevent the activation of caspases and decreased the neuronal apoptosis. MPP+ was microinjected into rat striatum using a stereotactic frame. The results showed increased activities of caspases 8, 9 and 3, between 72-120 hours after administration of MPP+, both in striatum and midbrain. After this study, we tested the effect of CuSO4 on MPP+ neurotoxicity, showing a diminution of the apoptotic damage induced by MPP+, decreased levels of enzymatic activity of caspases: 8 (-34 and -25 %), 9 (-25 and -42 %) and 3 (-40 and -29 %) in striatum and midbrain, respectively. Finally, we performed an immunohistochemical analysis, evidencing a decreased number of apoptotic cells in the groups pretreated with copper sulfate pretreatment compared to the control group. With these findings, it is concluded that pretreatment with copper sulfate may be a good alternative to prevent MPP+-induced apoptosis.

Decreased serotonin content and release in the ventral hippocampus of prenatally stressed male rats in response to forced swim test.

Prenatal stress modifies the serotonergic system by altering the synthesis, metabolism, receptors and serotonin content in the hippocampus. However, it is currently unknown whether serotonin release in the ventral hippocampus of prenatally stressed rats is altered. In this study, serotonin (5-HT) and its metabolite, 5­hydroxyindoleacetic acid (5-HIAA) levels were analysed in dialysates (in vivo) and in homogenates (in vitro) of the ventral hippocampus. This was made after the sucrose preference test and after forced swim test (FST) in male adult progeny from mothers that were stressed by immersion in cold water during the last week of gestation. Serum concentration of corticosterone was also evaluated in control and in prenatally stressed males. Sucrose preference was differently affected in prenatally stressed males: 69% showed decreased sucrose consumption, and were considered anhedonic; 31% exhibited sucrose consumption similar to control and were considered non­anhedonic. During the FST, increased immobility and decreased swimming were observed in prenatally stressed males. After sucrose test, content and release of 5­HT in prenatally stressed rats were similar to those in the control group, with higher metabolite. After the FST, 5-HT content increased, but its release increased slightly in anhedonic rats and did not change in non-anhedonic rats, with lower metabolite. The response of the adrenal axis to the FST was larger in anhedonic prenatally stressed males, than in control and non­anhedonic males. These data show that behavioural disruption caused by prenatal stress is related to low release and lower metabolism of serotonin in the ventral hippocampus in adult male offspring, as well as to hyperactivity and hyperreactivity of the adrenal axis.

Serotonin and noradrenaline content and release in the dorsal hippocampus during learning and spatial memory in prenatally stressed rats.

Prenatal stress causes learning and spatial memory deficits in adulthood by modifying hippocampal function. The dorsal hippocampus contains serotonergic and noradrenergic neuron terminals, which are related to cognitive processes. It is currently unknown whether prenatal stress modifies serotonin (5-HT) and noradrenaline (NA) content and their release in the hippocampus during cognitive performance. Therefore, we measured these variables in the dorsal hippocampus of prenatally stressed males during spatial learning and memory tests. Cognitive tests were performed in 3-month-old control and prenatally stressed male rats in the Morris Water Maze (MWM). After cognitive tests, the dorsal hippocampus was dissected to quantify 5-HT and NA content. In other males, 5-HT and NA release in the dorsal hippocampus was assessed by microdialysis, before and after cognitive tests. Prenatally stressed males showed longer latencies to reach the platform, compared to control animals. Hippocampal 5-HT content decreased during learning and memory tasks in both groups, while NA content was not modified in prenatally stressed males neither before, nor after learning and memory tests. 5-HT and NA release were significantly lower in prenatally stressed animals during spatial learning and memory tasks. Corticosterone response was greater in prenatally stressed animals compared to controls. These results show that cognitive disruption caused by prenatal stress is related to decreased 5-HT and NA release, and to higher adrenal axis response in prenatally stressed animals.

Caloric Restriction and Ketogenic Diet Therapy for Epilepsy: A Molecular Approach Involving Wnt Pathway and KATP Channels.

Epilepsy is a neurological disorder in which, in many cases, there is poor pharmacological control of seizures. Nevertheless, it may respond beneficially to alternative treatments such as dietary therapy, like the ketogenic diet or caloric restriction. One of the mechanisms of these diets is to produce a hyperpolarization mediated by the adenosine triphosphate (ATP)-sensitive potassium (KATP) channels (KATP channels). An extracellular increase of K+ prevents the release of Ca2+ by inhibiting the signaling of the Wnt pathway and the translocation of ß-catenin to the cell nucleus. Wnt ligands hyperpolarize the cells by activating K+ current by Ca2+. Each of the diets described in this paper has in common a lower use of carbohydrates, which leads to biochemical, genetic processes presumed to be involved in the reduction of epileptic seizures. Currently, there is not much information about the genetic processes implicated as well as the possible beneficial effects of diet therapy on epilepsy. In this review, we aim to describe some of the possible genes involved in Wnt pathways, their regulation through the KATP channels which are implicated in each one of the diets, and how they can reduce epileptic seizures at the molecular level.

Hydroxytyrosol inhibits MAO isoforms and prevents neurotoxicity inducible by MPP+ invivo.

Parkinson's disease is considered to be due to an increase in the catabolism of dopamine by the action of monoamine oxidase (MAO) enzymes which leads to an increase in reactive oxygen species (ROS) and loss of dopaminergic neurons. Here, in a model of neurotoxicity inducible by 1-methyl-4-phenylpyridinium (MPP+), we tested the effect of hydroxytyrosol (HTy), a potent antioxidant, on generation of ROS. Five minutes after a single intravenous administration of 1.5 mg/Kg of Hty, Wistar rats received an intrastriatal micro-injection of 10 micrograms of MPP+ while control animals received saline solution. Six days later, all animals were treated with apomorphine (1 mg/Kg), subcutaneously and ipsilateral rotations were assessed within an hour. Then, the rats were sacrificed, striatal tissues were removed and their catecholamines and MAO-A and B activities were quantitated. Pretreatment with HTy significantly diminished the number of ipsilateral rotations. This recovery correlated with significant preservation of striatal dopamine and significant inhibition of of the MAO activity. These results are consistent with the inhibitory effect of HTy on the MAO isoforms and form a basis for the neuroprotective mechanism of this phenylpropanoid in MPP+ induced Parkinson's disease.

Activation of the Extrinsic and Intrinsic Apoptotic Pathways in Cerebellum of Kindled Rats.

The purpose of this study is to determine the activation of the extrinsic and intrinsic apoptotic pathways in the cerebellum of rats exposed to amygdaloid electrical kindling. Western blot analyses were carried out for caspase-8 and caspase-9, Bid, Bax, and Bcl-2 in the cerebellum and immunohistochemistry of Bid, Bax, cytochrome C, and VDAC (voltage-dependent anion channels) in the cerebellar cortex of Wistar male rats with 0, 15, and 45 kindling stimulations. In the experimental group of 45 stimuli, we observed an increase in protein activation of caspase-9 and truncated Bid and Bax, in addition to a decrease in expression of pro-caspase-8 and the anti-apoptotic protein Bcl-2, determined by Western blot. Moreover, we observed a cytosolic immunopositivity for cytochrome C and a mitochondrial immunolocalization for truncated Bid and Bax in the group of 45 stimuli. In this work, we found an increase of caspase-8, a cysteine-protease that can activate caspase-3 triggering extrinsic apoptosis by signaling of death receptors. However, it also can activate the intrinsic pathway releasing Bid, which performs mitochondrial translocation of Bax, inactivating Bcl-2 and allowing the release of cytochrome C through the opening of the mitochondrial permeability transition pore, promoting the activation of caspase-9 which activates caspase-3, the main executor caspase of apoptosis. Therefore, it is concluded that there is an activation of the intrinsic and extrinsic apoptotic pathways in the cerebellum of rats exposed to the kindling model. Apoptosis signaling pathways can be analyzed as an important developing object of research about the epileptic activity. Graphical Abstract.

Epicatechin Reduces Spatial Memory Deficit Caused by Amyloid-ß25⁻35 Toxicity Modifying the Heat Shock Proteins in the CA1 Region in the Hippocampus of Rats.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by dementia and the aggregation of the amyloid beta peptide (Aß). Aß25-35 is the most neurotoxic sequence, whose mechanism is associated with the neuronal death in the Cornu Ammonis 1 (CA1) region of the hippocampus (Hp) and cognitive damage. Likewise, there are mechanisms of neuronal survival regulated by heat shock proteins (HSPs). Studies indicate that pharmacological treatment with flavonoids reduces the prevalence of AD, particularly epicatechin (EC), which shows better antioxidant activity. The aim of this work was to evaluate the effect of EC on neurotoxicity that causes Aß25-35 at the level of spatial memory as well as the relationship with immunoreactivity of HSPs in the CA1 region of the Hp of rats. Our results show that EC treatment reduces the deterioration of spatial memory induced by the Aß25-35, in addition to reducing oxidative stress and inflammation in the Hp of the animals treated with EC + Aß25-35. Likewise, the immunoreactivity to HSP-60, -70, and -90 is lower in the EC + Aß25-35 group compared to the Aß25-35 group, which coincides with a decrease of dead neurons in the CA1 region of the Hp. Our results suggest that EC reduces the neurotoxicity induced by Aß25-35, as well as the HSP-60, -70, and -90 immunoreactivity and neuronal death in the CA1 region of the Hp of rats injected with Aß25-35, which favors an improvement in the function of spatial memory.

Neurorehabilitation of saccadic ocular movement in a patient with a homonymous hemianopia postgeniculate caused by an arteriovenous malformation: A Case Report.

RATIONALE: Visual therapy, which includes a restorative and compensatory approach, seems to be a viable treatment option for homonymous defects of the visual field in patients with postgeniculate injury of the visual pathway, due to occipital arteriovenous malformation (AVM). Until now, the Mexican population suffering from homonymous hemianopia did not have health services that provided any type of visual therapy for their condition. PATIENT CONCERNS: A 31-year-old patient, who underwent a surgical procedure for resection of the AVM, was referred with posterior low vision on the left side. DIAGNOSES: The patient was diagnosed with left homonymous hemianopia. INTERVENTIONS: Visual neurorehabilitation therapy (NRT), which integrated restorative and compensatory approaches, was administered for 3 hours each week. NRT included fixation, follow-up, search, peripheral vision, and reading. OUTCOMES: The NRT did not change visual field defects and, retinotopocally, the same campimetric defects remained. However, after training the tracking ocular movements improved to standard values on the ENG, further, the visual search became more organized. The reading reached a level without mistakes, with rhythm and goog intonation. The Beck test demostrated an improvement in depression symptoms. Regarding the daily life activities, the patient reported significant improvements. LESSONS: Visual NRT can significantly improve eye movements, as well as the quality of life and independence of the patient. This integral approach could be an effective therapeutic option for homonymous defects of the visual field.

Copper sulfate pretreatment prevents mitochondrial electron transport chain damage and apoptosis against MPP+-induced neurotoxicity.

Intrastriatal injection of 1-methyl-4-phenylpyridinium (MPP+) is considered a model to reproduce some biochemical alterations observed in Parkinson's disease (PD) patients. Among those alterations, inhibition of mitochondrial complex I activity, increased free radical production and reduced antioxidant responses have been reported. Copper (Cu) plays an important role in the metabolism and antioxidative responses through its participation as a cofactor in the cytochrome c oxidase enzyme (COX), Cu/Zn-superoxide dismutase (Cu/Zn-SOD), and metallothioneins. We tested the effect of copper sulfate (CuSO4) pretreatment on the mitochondrial electron transport chain (METC) in the striatum after MPP+ toxicity in rats. The results showed that the MPP+ intrastriatal injection reduced mitochondrial complex I, II, IV and V activities; while 10 µmol of CuSO4 pretreatment counteracted this damage. Activities of complexes I, II and IV, were coincident with ATP recovery. Moreover, Cu/Zn-SOD activity was reduced as a consequence of MPP+ damage; however, copper pre-treatment kept the striatal Cu/Zn-SOD activity unchanged in MPP+-damaged animals. We observed that MPP+ also reduced the metallothionein (MT) content and that CuSO4 pretreatment maintained baseline values. CuSO4 pretreatment also reduced the striatal caspase-3 and caspase-9 activities that were increased three days after MPP+-induced damage. The present study provided evidence that copper pretreatment reduced MPP+-induced apoptotic damage, probably through direct action on copper-dependent proteins or indirectly on proteins in the apoptotic pathway.