Physical training mitigates alveolar bone and blood enzymatic antioxidants defense impairment induced by binge ethanol consumption in rats

We aimed to investigate the effectiveness of physical training as a protective strategy to mitigate alveolar bone damage and blood antioxidant defense caused by ethanol (EtOH) consumption in a binge-drinking pattern. Male Wistar rats aged approximately 90 days were divided into four groups: control, training, EtOH, and training + EtOH. The physical training protocol was conducted on a treadmill for four consecutive weeks, while the animals in the EtOH group were administered EtOH via orogastric gavage for three consecutive days each week, following the binge drink pattern. After the training period, blood and mandibles were collected for plasma oxidative biochemistry analysis, and the alveolar bone was subjected to physicochemical composition analysis, tissue evaluation, and microtomography evaluation. Our results showed that EtOH induced oxidative stress and physical exercise promoted the recovery of antioxidant action. Physical training minimized the damage to the mineral/matrix composition of the alveolar bone due to EtOH consumption and increased the density of osteocytes in the trained group treated with EtOH than in those exposed only to EtOH. Furthermore, physical training reduced damage to the alveolar bone caused by EtOH consumption. Our findings suggest that physical training can serve as an effective strategy to reduce systemic enzymatic oxidative response damage and alleviate alveolar bone damage resulting from alcohol consumption. Further investigations are warranted to elucidate the underlying mechanisms and explore, in addition to physical training, the potential effects of other activities with varying intensities on managing alcohol-induced bone damage.

Amazonian Plants: A Global Bibliometric Approach to Petiveria alliacea L. Pharmacological and Toxicological Properties

Petiveria alliacea L. (Phytolaccaceae) holds significant importance in the Amazon region, where it has been traditionally utilized in folk medicine. In this study, we conducted a comprehensive bibliometric analysis using conventional metrics, combined with a critical content review of its pharmacological and toxicological properties, to identify gaps in the existing literature that require further investigation. Our investigation identified a total of 55 articles that met the inclusion criteria for this study. Remarkably, Brazil emerged as the primary contributor within the scope of this review, indicating a strong presence of research from this country. Furthermore, professional scientific societies have played a pivotal role in facilitating the dissemination of scientific findings through specialist journals, fostering the sharing of research work within the community. Analysis of keyword co-occurrence revealed that "Petiveria alliacea", "plant extract", and "guatemala" were the most frequently encountered terms, indicating their significance within the literature. In terms of study designs, in vivo and in vitro were the predominant types observed, highlighting their prevalence in this field of study. Our study also identified a lack in knowledge yet to be investigated.

Ketamine Clinical Use on the Pediatric Critically Ill Infant: A Global Bibliometric and Critical Review of Literature

The developing central nervous system is vulnerable to several stimuli, especially psychotropic drugs. Sedation procedures during the developmental period are frequent in pediatric intensive care units (PICUs), in which the use of the sedative agent is still a challenge for the PICU team. Ketamine has been indicated for sedation in critically ill children with hemodynamic and ventilatory instabilities, but the possible neurobehavioral consequences related to this use are still uncertain. Here, we performed a bibliometric analysis with conventional metrics and a critical review of clinical findings to reveal a gap in the literature that deserves further investigation. We revealed that only 56 articles corresponded to the inclusion criteria of the study. The United States of America emerges as the main country within the scope of this review. In addition, professional clinical societies play a key role in the publications of scientific clinical findings through the specialist journals, which encourages the sharing of research work. The co-occurrence of keywords evidenced that the terms "sedation", "ketamine", and "pediatric" were the most frequent. Case series and review articles were the most prevalent study design. In the critical evaluation, the scarce studies highlight the need of use and post-use monitoring, which reinforces the importance of additional robust clinical studies to characterize the possible adverse effects resulting from ketamine anesthetic protocol in critically ill children.

Deciphering the Global Proteomic Profile Involved in Methylmercury-Induced Cerebellar Neurodegeneration and Motor Dysfunction in Adult Rats

Mercury is a ubiquitous pollutant in the environment with potential neurotoxic effects. Several populations are susceptible to mercurial exposure, especially methylmercury (MeHg) at low doses for long periods through food consumption. Given this, the present work aimed to assess the effects of long-term MeHg exposure on the cerebellum of rats from a translational perspective using a representative dose, assessing molecular, biochemical, morphological, and behavioral parameters. The model was produced by administering 40 µg/kg of MeHg for 60 days to adult male Wistar rats by oral gavage. As a result of this exposure, the animals presented motor deficits in open field and rotarod tests which were associated with an increase in total mercury content in cerebellar parenchyma, a reduction in antioxidant competence against peroxyl radicals, and increased nitrite and lipid peroxidation levels. The proteomic approach showed 317 modulated proteins. Such findings were associated with reductions in mature neuron and Purkinje cell densities and glial fibrillary acidic protein immunostained areas and increased microglial density. In addition, decreases in myelin basic protein and synaptophysin immunostaining were also observed. The results thus provided new evidence of the mechanisms underlying complex MeHg-induced neurodegeneration, especially the proteins underlying the biochemical and morphological features associated with motor dysfunction.

Effects of Fluoride Long-Term Exposure over the Cerebellum: Global Proteomic Profile, Oxidative Biochemistry, Cell Density, and Motor Behavior Evaluation

Although the literature does not provide evidence of health risks from exposure to fluoride (F) in therapeutic doses, questions remain about the effects of long-term and high-dose use on the function of the central nervous system. The objective of this study was to investigate the effect of long-term exposure to F at levels similar to those found in areas of artificial water fluoridation and in areas of endemic fluorosis on biochemical, proteomic, cell density, and functional parameters associated with the cerebellum. For this, mice were exposed to water containing 10 mg F/L or 50 mg F/L (as sodium fluoride) for 60 days. After the exposure period, the animals were submitted to motor tests and the cerebellum was evaluated for fluoride levels, antioxidant capacity against peroxyl radicals (ACAP), lipid peroxidation (MDA), and nitrite levels (NO). The proteomic profile and morphological integrity were also evaluated. The results showed that the 10 mg F/L dose was able to decrease the ACAP levels, and the animals exposed to 50 mg F/L presented lower levels of ACAP and higher levels of MDA and NO. The cerebellar proteomic profile in both groups was modulated, highlighting proteins related to the antioxidant system, energy production, and cell death, however no neuronal density change in cerebellum was observed. Functionally, the horizontal exploratory activity of both exposed groups was impaired, while only the 50 mg F/L group showed significant changes in postural stability. No motor coordination and balance impairments were observed in both groups. Our results suggest that fluoride may impair the cerebellar oxidative biochemistry, which is associated with the proteomic modulation and, although no morphological impairment was observed, only the highest concentration of fluoride was able to impair some cerebellar motor functions.

Hippocampal Impairment Triggered by Long-Term Lead Exposure from Adolescence to Adulthood in Rats: Insights from Molecular to Functional Levels

Lead (Pb) is an environmental and occupational neurotoxicant after long-term exposure. This study aimed to investigate the effects of systemic Pb exposure in rats from adolescence to adulthood, evaluating molecular, morphologic and functional aspects of hippocampus. For this, male Wistar rats were exposed to 50 mg/kg of Pb acetate or distilled water for 55 days by intragastric gavage. For the evaluation of short-term and long-term memories, object recognition and step-down inhibitory avoidance tests were performed. At the end of the behavioral tests, the animals were euthanized and the hippocampus dissected and processed to the evaluation of: Pb content levels in hippocampal parenchyma; Trolox equivalent antioxidant capacity (TEAC), glutathione (GSH) and malondialdehyde (MDA) levels as parameters of oxidative stress and antioxidant status; global proteomic profile and neuronal degeneration by anti-NeuN immunohistochemistry analysis. Our results show the increase of Pb levels in the hippocampus of adult rats exposed from adolescence, increased MDA and GSH levels, modulation of proteins related to neural structure and physiology and reduced density of neurons, hence a poor cognitive performance on short and long-term memories. Then, the long-term exposure to Pb in this period of life may impair several biologic organizational levels of the hippocampal structure associated with functional damages.

Pellucidin A promotes antinociceptive activity by peripheral mechanisms inhibiting COX-2 and NOS: In vivo and in silico study

Peperomia pellucida (PP) belongs to the Peperomia genus, which has a pantropic distribution. PP is used to treat a wide range of symptoms and diseases, such as pain, inflammation, and hypertension. Intriguingly, PP extract is used by different tropical countries for its anti-inflammatory and antinociceptive effects. In fact, these outcomes have been shown in animal models, though the exact bioactive products of PP that exert such results are yet to be discovered. To determine and elucidate the mechanism of action of one of these compounds, we evaluated the antinociceptive effect of the novel dimeric ArC2 compound, Pellucidin A by using in vivo and in silico models. Animals were then subjected to chemical, biphasic and thermal models of pain. Pellucidin A induced an antinociceptive effect against chemical-induced pain in mice, demonstrated by the decrease of the number of writhes, reaching a reduction of 43% and 65% in animals treated with 1 and 5 mg/kg of Pellucidin A, respectively. In the biphasic response (central and peripheral), animals treated with Pellucidin A showed a significant reduction of the licking time exclusively during the second phase (inflammatory phase). In the hot-plate test, Pellucidin A did not have any impact on the latency time of the treated animals. Moreover, in vivo and in silico results show that Pellucidin A’s mechanism of action in the inflammatory pain occurs most likely through interaction with the nitric oxide (NO) pathway. Our results demonstrate that the antinociceptive activities of Pellucidin A operate under mechanism(s) of peripheral action, involving inflammatory mediators. This work provides insightful novel evidence of the biological properties of Pellucidin A, and leads to a better understanding of its mechanism of action, pointing to potential pharmacological use.

Proteomic approach underlying the hippocampal neurodegeneration caused by low doses of methylmercury after long-term exposure in adult rats

Methylmercury (MeHg) is an important toxicant that causes cognitive dysfunctions in humans. This study aimed to investigate the proteomic and biochemical alterations of the hippocampus associated with behavioural consequences of low doses of MeHg in a long-term exposure model, and to realistically mimic in vivo the result of human exposure to this toxicant. Adult Wistar male rats were exposed to a dose of MeHg at 0.04 mg kg-1 day-1 by gavage for 60 days. Total mercury (Hg) content was significantly increased in the hippocampal parenchyma. The increase in the Hg levels was capable of reducing neuron and astrocyte cell density in the CA1, CA3, hilus and dentate gyrus regions, increasing both malondialdehyde and nitrite levels and decreasing antioxidant capacity against peroxyl radicals. The proteomic analysis detected 1041 proteins with altered expression due to MeHg exposure, including 364 proteins with no expression, 295 proteins with de novo expression and 382 proteins with up- or down-regulated expression. This proteomic approach revealed alterations in pathways related to chemical synapses, metabolism, amino acid transport, cell energy, neurodegenerative processes and myelin maintenance. Therefore, even at low doses of MeHg exposure, it is possible to cause hippocampal damage in adult rats at many organisational levels, triggering oxidative stress and proteome misbalance, featuring a neurodegenerative process and culminating in long- and short-term memory and learning deficits.

Neurochemical dysfunction in motor cortex and hippocampus impairs the behavioral performance of rats chronically exposed to inorganic mercury

Chronic exposure to mercury chloride (HgCl₂) has been shown to promote oxidative stress and cell death in the central nervous system of adult rats displaying motor and cognitive impairments. However, there are no investigations about neurochemical function after this type of exposure in rodents that may be associated with those behavioral changes already reported. Thus, the aim of this study was to analyze glutamatergic and GABAergic dysfunctions in the motor cortex and hippocampus of adult rats, in a model of chronic exposure to HgCl₂ in. Twenty rats were exposed to a daily dose of 0.375 mg/kg for 45 days. After this period, they were submitted to motor and cognitive functions tests and euthanized to collect the motor cortex and hippocampus for measurement of mercury (Hg) levels in the parenchyma and neurochemical assays for analysis of glutamatergic and GABAergic functions. It was observed that chronic exposure to HgCl₂ promoted increase in total Hg levels in these two brain areas, with changes in glutamatergic transport, but without changes in GABAergic transport. Functionally this model of exposure caused the decrease of the spontaneous motor locomotion and in the process of learning and memory. In this way, our results provide evidences that glutamatergic neurochemical dysfunction can be pointed out as a strong causal factor of motor and cognitive deficits observed in rats exposed to this HgCl₂.

Repeated Cycles of Binge-Like Ethanol Intake in Adolescent Female Rats Induce Motor Function Impairment and Oxidative Damage in Motor Cortex and Liver, but Not in Blood

Moderate ethanol consumption (MEC) is increasing among women. Alcohol exposure usually starts in adolescence and tends to continue until adulthood. We aimed to investigate MEC impacts during adolescence until young adulthood of female rats. Adolescent female Wistar rats received distilled water or ethanol (3 g/kg/day), in a 3 days on-4 days off paradigm (binge drinking) for 1 and 4 consecutive weeks. We evaluate liver and brain oxidative damage, peripheral oxidative parameters by SOD, catalase, thiol contents, and MDA, and behavioral motor function by open-field, pole, beam-walking, and rotarod tests. Our results revealed that repeated episodes of binge drinking during adolescence displayed lipid peroxidation in the liver and brain. Surprisingly, such oxidative damage was not detectable on blood. Besides, harmful histological effects were observed in the liver, associated to steatosis and loss of parenchymal architecture. In addition, ethanol intake elicited motor incoordination, bradykinesia, and reduced spontaneous exploratory behavior in female rats.

Unravelling motor behaviour hallmarks in intoxicated adolescents: methylmercury subtoxic-dose exposure and binge ethanol intake paradigm in rats

Methylmercury (MeHg) is a hazardous environmental pollutant, affecting Amazon basin communities by anthropogenic activities. The exact safe level of MeHg exposure is unclear, despite the efforts of health international societies to avoid mercury (Hg) poisoning. Central nervous system is severely impacted by Hg intoxication, reflecting on motor impairment. In addition, alcohol has been associated to an overall brain damage. According to lifestyle of Amazon riverside communities, alcohol intake occurs frequently. Thus, we investigated if continuous MeHg exposure at low doses during adolescence displays motor deficits (experiment 1). In the experiment 2, we examine if the co-intoxication (i.e. MeHg plus ethanol exposure) during adolescence intensify motor damage. In the experiment 1, Wistar adolescent rats (31 days old) received chronic exposure to low dose (CELD) of MeHg (40 μg/kg/day) for 35 days. For the experiment 2, five sessions of alcohol binge drinking paradigm (3ON-4OFF; 3.0 g/kg/day) were employed associated to MeHg intoxication. Motor behaviour was evaluated by the open field, pole test, beam walking and rotarod paradigms. CELDS of MeHg display motor function damage, related to hypoactivity, bradykinesia-like behaviour, coordination deficits and motor learning impairment. Co-intoxication of MeHg plus ethanol reduced cerebellar Hg content, however also resulted in motor behavioural impairment, as well as additive effects on bradykinesia and fine motor evaluation.

Low doses of methylmercury intoxication solely or associated to ethanol binge drinking induce psychiatric-like disorders in adolescent female rats

Methylmercury (MeHg) is an environmental contaminant that provokes damage to developing brain. Simultaneously, the consumption of ethanol among adolescents has increased. Evidence concerning the effects of MeHg low doses per se or associated with ethanol during adolescence are scarce. Thus, we investigate behavioral disorders resulted from exposure to MeHg low doses and co-intoxicated with ethanol in adolescent rats. Wistar rats received chronic exposure to low doses of MeHg (40 μg/kg/day for 5 weeks) and/or ethanol binge drinking (3 g/kg/day at 3 days per week for 5 weeks). Animals were submitted to behavioral assays to assess emotionality and cognitive function. Total mercury content was evaluated in the brain and hair. Oxidative parameters were analyzed in blood samples. MeHg at low doses or associated to ethanol binge drinking produced psychiatric-like disorders and cognitive impairment. Peripherally, MeHg altered oxidative parameters when associated to ethanol. Ethanol administration reduced brain mercury deposit. We proposed that ethanol reduces the necessity of mercury tissue levels to display psychiatric-like disorders/cognitive impairment.

Chronic exposure to inorganic mercury induces biochemical and morphological changes in the salivary glands of rats

Mercury exposure is considered to be a public health problem due to the generation of toxic effects on human health as a result of environmental and occupational conditions. The inorganic form of mercury (HgCl₂) can cause several biological changes in cells and tissues through its cumulative toxic potential, but little has been experimentally proven about the effects of inorganic mercury on salivary glands, an important modulator organ of oral health. This study analyzes the effects of prolonged low dose exposure to HgCl₂ on the salivary glands of rats. Adult animals received a dose of 0.375 mg kg^-1 day^-1 over a period of 45 days. The parotid and submandibular glands were collected for analysis of the mercury levels and evaluation of oxidative stress, histological parameters and immunomodulation for metallothionein I and II (MT-I/II). In this investigation, biochemical and tissue changes in the salivary glands were verified due to the mercury levels, causing reduction in antioxidant capacity against peroxyl radicals, with consequent cellular lipid peroxidation and an increase in nitrite levels, volumetric changes and cytoskeletal damage in the submandibular glands, with less severe damage to the parotid glands. The results also have shown the occurrence of a cytoprotection mechanism due to increased MT-I/II expression, but not enough to avoid the morphology and oxidative damage. This evidence highlights, for the first time, that inorganic mercury is able to alter the morphology and oxidative biochemistry in salivary glands when exposed for a long time in low doses.

Ethnobotany, phytochemistry and neuropharmacological effects of Petiveria alliacea L. (Phytolaccaceae): A review

ETHNOPHARMACOLOGICAL RELEVANCE

Petiveria alliacea L. commonly grows in the tropical regions of the Americas such as the Amazon forest, Central America, Caribbean islands and Mexico, as well as specific regions of Africa. Popularly known by several different names including 'mucuracaá', 'guiné' and 'pipi', P. alliacea has been used in traditional medicine for the treatment of various central nervous system (CNS) disorders, such as anxiety, pain, memory deficits and seizures, as well as for its anaesthetic and sedative properties. Furthermore, the use of this species for religious ceremonies has been reported since the era of slavery in the Americas. Therefore, the present review aims to provide a critical and comprehensive overview of the ethnobotany, phytochemistry and pharmacological properties of P. alliacea, focusing on CNS pharmacological effects, in order to identify scientific lacunae and to open new perspectives for future research.

MATERIALS AND METHODS

A literature search was performed on P. alliacea using ethnobotanical textbooks, published articles in peer-reviewed journals, unpublished materials, government survey reports and scientific databases such as PubMed, Scopus, Web of Science, Science Direct and Google Scholar. The Plant List, International Plant Name Index and Kew Botanical Garden Plant name databases were used to validate the scientific names.

RESULTS AND DISCUSSION

Crude extracts, fractions and phytochemical constituents isolated from various parts of P. alliacea show a wide spectrum of neuropharmacological activities including anxiolytic, antidepressant, antinociceptive and anti-seizure, and as cognitive enhancers. Phytochemistry studies of P. alliacea indicate that this plant contains a diversity of biologically active compounds, with qualitative and quantitative variations of the major compounds depending on the region of collection and the harvest season, such as essential oil (Petiverina), saponinic glycosides, isoarborinol-triterpene, isoarborinol-acetate, isoarborinol-cinnamate, steroids, alkaloids, flavonoids and tannins. Root chemical analyses have revealed coumarins, benzyl-hydroxy-ethyl-trisulphide, benzaldehyde, benzoic acid, dibenzyl trisulphide, potassium nitrate, b-sitosterol, isoarborinol, isoarborinol-acetate, isoarborinol-cinnamate, polyphenols, trithiolaniacine, glucose and glycine.

CONCLUSIONS

Many traditional uses of P. alliacea have now been validated by modern pharmacology research. The available data reviewed here support the emergence of P. alliacea as a potential source for the treatment of different CNS disorders including anxiety, depression, pain, epilepsy and memory impairments. However, further studies are certainly required to improve the knowledge about the mechanisms of action, toxicity and efficacy of the plant as well as about its bioactive compounds before it can be approved in terms of its safety for therapeutic applications.

Neurological disease in human and canine leishmaniasis--clinical features and immunopathogenesis

Leishmaniasis is a vectorborne disease caused by Leishmania protozoa, which is a major health problem and a neglected disease common in many regions of the world. Leishmania is an intracellular parasite transmitted by sand flies that causes clinical manifestations ranging from a severe and potentially fatal disease named visceral leishmaniasis to less severe but in many cases disfiguring diseases that mainly affect the skin or mucosal tissues, known as cutaneous leishmaniasis. Despite the detection of Leishmania parasites in the brain and cerebrospinal fluid of human patients and dogs, epidemiological data, as well as information about the mechanisms of central and peripheral nervous system alterations, are poorly described. This review is focused on the current knowledge about the neurological manifestations and immunopathogenic mechanisms in human patients and animals infected with Leishmania.

Petiveria alliacea exerts mnemonic and learning effects on rats

ETHNOPHARMACOLOGICAL RELEVANCE

Petiveria alliacea L. (Phytolaccaceae) is a perennial shrub native to the Amazon region and other tropical areas such as Central America and the Caribbean. Popularly known as mucuracaá, P. alliacea is used in the folk medicine for a broad variety of therapeutic purpose and also in religious ceremonies by slaves as a sedative, which highlights its properties on the Central Nervous System (CNS).

AIM OF THE STUDY

The present study evaluated the effects of the P. alliacea leaves hydroalcoholic extract (PaLHE) on the cognition, including learning and memory.

MATERIAL AND METHODS

Three-month-old male and female Wistar rats (n=8-10/group) were administered with 900mg/kg of PaLHE. The behavioral assays included Step-down Inhibitory avoidance (IA) and Morris Water Maze (MWM) tests.

RESULTS

Consistent with our previous reports, P. alliacea improved long-term memory. It also exerted previously unreported effects on short-term and spatial memory improvement, and increased learning in the tasks.

CONCLUSIONS

The P. alliacea extract elicited mnemonic effects and improved the learning process in both IA and MWM tests. Our results highlight the importance of further studies in order to identify the active substances of the PaLHE and investigate the pharmacological mechanisms that underlies the reported effects.

Immunohistochemical changes and atrophy after chronic ethanol intoxication in rat salivary glands

Alcoholism in humans is a chronic and progressive disease, characterized by loss of ethanol consumption control. Previous studies have reported that prolonged exposure to ethanol was responsible for alterations in glandular tissues of human and rodents. However, the interrelationship between ethanol and the glandular system is still the subject of numerous investigations, including the possible resistance of the submandibular gland (SG). In the present study, we investigated whether chronic ethanol exposure during adolescence may affect the parotid gland (PG) and SG in female rats. Female rats (n=16) were treated with distilled water or ethanol (dose of 6.5 g/kg/day, 22.5% w/v) through gavage for 55 days. Glands were collected, weighed and submitted to histological processing. Morphometric analysis was assessed by parenchymal and stromal area measurements. Smooth muscle actin (α-SMA), cytokeratin-19 (CK19) and apoptotic caspase-3 (CAS) were measured using ImageJ® software. Chronic ethanol administration did not alter the body weight of rats after treatment, although it increased glandular weight (p<0.001), reduced the parenchyma area (p<0.001) and decreased CK19 and α-SMA immunostainning in the PG. Besides, ethanol induced CK19 and CAS overexpression, and the occurrence of duct-like structures in SG. These results suggest that ethanol induces histological and morphometric changes in salivary glands of female rats intoxicated with ethanol during adolescence. Furthermore, the mechanism underlying these alterations needs to be investigated but may be not related to the inflammatory process.

Chronic ethanol exposure during adolescence in rats induces motor impairments and cerebral cortex damage associated with oxidative stress

Binge drinking is common among adolescents, and this type of ethanol exposure may lead to long-term nervous system damage. In the current study, we evaluated motor performance and tissue alterations in the cerebral cortex of rats subjected to intermittent intoxication with ethanol from adolescence to adulthood. Adolescent male Wistar rats (35 days old) were treated with distilled water or ethanol (6.5 g/kg/day, 22.5% w/v) during 55 days by gavage to complete 90 days of age. The open field, inclined plane and the rotarod tests were used to assess the spontaneous locomotor activity and motor coordination performance in adult animals. Following completion of behavioral tests, half of animals were submitted to immunohistochemical evaluation of NeuN (marker of neuronal bodies), GFAP (a marker of astrocytes) and Iba1 (microglia marker) in the cerebral cortex while the other half of the animals were subjected to analysis of oxidative stress markers by biochemical assays. Chronic ethanol intoxication in rats from adolescence to adulthood induced significant motor deficits including impaired spontaneous locomotion, coordination and muscle strength. These behavioral impairments were accompanied by marked changes in all cellular populations evaluated as well as increased levels of nitrite and lipid peroxidation in the cerebral cortex. These findings indicate that continuous ethanol intoxication from adolescence to adulthood is able to provide neurobehavioral and neurodegenerative damage to cerebral cortex.

Neurological and behavioral manifestations of cerebral malaria: An update

Neglected tropical diseases are a group of tropical diseases endemic in poor countries even though medical treatment and cures are available. They are considered a global health problem due to the severity of the physiological changes they induce in their hosts. Malaria is a disease caused by Plasmodium sp. that in its cerebral form may lead to acute or long-term neurological deficits, even with effective antimalarial therapy, causing vascular obstruction, reduced cerebral blood flow and many other changes. However, Plasmodium falciparum infection can also develop into a cerebral malaria (CM) disease that can produce neurological damage. This review will discuss the mechanisms involved in the neuropathology caused by CM, focusing on alterations in cognitive, behavior and neurological functions in human and experimental models.

Minocycline mitigates motor impairments and cortical neuronal loss induced by focal ischemia in rats chronically exposed to ethanol during adolescence

Ethanol is an important risk factor for the occurrence of cerebral ischemia contributing to poor prognosis and inefficacy of drug treatments for stroke-related symptoms. Females have a higher lifetime risk for stroke than males. Moreover, female gender has been associated with increased ethanol consumption during adolescence. In the present study, we investigated whether chronic ethanol exposure during adolescence may potentiate the motor impairments and cortical damage induced by focal ischemia in female rats. We also addressed whether these effects can be mitigated by minocycline, which has been shown to be neuroprotective against different insults in the CNS. Female rats were treated with distilled water or ethanol (6.5 g/kg/day, 22.5% w/v) for 55 days by gavage. Focal ischemia was induced by microinjections of endothelin-1 (ET-1) into the motor cortex. Animals of both groups were treated daily with minocycline (25-50 mg/kg, i.p.) or sterile saline (i.p.) for 5 days, and motor function was assessed using open field, inclined plane and rotarod tests. Chronic ethanol exposure exacerbated locomotor activity and motor coordination impairments induced by focal ischemia in rats. Moreover, histological analysis revealed that microinjections of ET-1 induced pyramidal neuron loss and microglial activation in the motor cortex. Minocycline reversed the observed motor impairments, microglial activation and pyramidal neuron loss in the motor cortex of ischemic rats even in those exposed to ethanol. These results suggest that minocycline induces neuroprotection and functional recovery in ischemic female rats intoxicated with ethanol during adolescence. Furthermore, the mechanism underlying this protective effect may be related to the modulation of neuroinflammation.