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1.
PLoS One ; 19(1): e0295811, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38241264

RESUMO

The utilisation of insect meal-based fish feed as a substitute for conventional fish meal-based fish feed is considered as a promising innovative alternative to boost circularity in aquaculture and aquaponics. Basic research on its use in aquaponics is limited. So far, no reports on the effects of fish waste water, derived from a recirculating aquaculture system using Black Soldier Fly (BSF) meal-based diets, were available on the growth performance of lettuce. Therefore, this study aimed to compare the effect of reusing fish waste water from tilapia culture (as a base for the nutrient solution) fed with a fish meal-based diet (FM) and a BSF meal-based diet on resource use and lettuce growth in decoupled aquaponic systems. A conventional hydroponics nutrient solution (HP) served as control, and inorganic fertilisers were added to all nutrient solutions to reach comparable target concentrations. The experiment was conducted in a controlled climate chamber in nine separate hydroponics units, three per treatment. Lettuce fresh and dry weight, number of leaves, relative leaf chlorophyll concentration, water consumption, and the usage of inorganic fertilisers were measured. Micro- and macronutrients in the nutrient solutions were monitored in time series. Similar lettuce yield was seen in all treatments, with no significant effects on fresh and dry weight, the number of leaves, and relative chlorophyll values. Water use per plant was also similar between treatments, while the amount of total inorganic fertiliser required was 32% lower in FM and BSF compared to HP. Higher sodium concentrations were found in the FM nutrient solutions compared to BSF and HP. The results confirm that BSF-based diet is a promising alternative to FM-based diet in aquaponics with no negative effects on lettuce growth. Additionally, BSF-based diet might be beneficial in intensive, professional aquaponics applications due to the lower sodium concentration in the nutrient solution.


Assuntos
Dípteros , Lactuca , Animais , Águas Residuárias , Fertilizantes , Peixes , Clorofila , Sódio
2.
Trials ; 24(1): 245, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37004121

RESUMO

BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs) and analgesics are used frequently by athletes either prophylactically for the prevention of pain, or to accelerate recovery following an injury. However, these types of pain management strategies have been shown to inhibit signalling pathways (e.g., cyclooxygenase-2) that may hinder muscular adaptations such as hypertrophy and strength. Nutraceuticals such as palmitoylethanolamide (PEA) have analgesic properties that act via different mechanisms to NSAIDS/analgesics. Furthermore, PEA has been shown to have a positive effect on sleep and may contribute positively to muscle hypertrophy via PKB activation. Although PEA has not been widely studied in the athletic or recreationally active population, it may provide an alternative solution for pain management if it is found not to interfere with, or enhance training adaptations. Therefore, the study aim is to investigate the effects of daily PEA supplementation (Levagen + ®) with resistance training on lean body mass, strength, power and physical performance and outcomes of recovery (e.g., sleep) compared to placebo. METHODS: This double-blind, randomised controlled study will take place over an 11-week period (including 8-weeks of progressive resistance training). Participants for this study will be 18-35 years old, healthy active adults that are not resistance trained. Participants will attend a familiarisation (week 0), pre-testing (week 1) and final-testing (week 11). At the pre-testing and final-testing weeks, total lean body mass (dual-energy X-ray absorptiometry; DXA), total mid-thigh cross sectional area (pQCT), maximal muscular strength (1 repetition maximum bench press, isometric mid-thigh pull) and power (countermovement jump and bench throw) will be assessed. Additionally, circulating inflammatory cytokines and anabolic hormones, sleep quality and quantity (ActiGraph), pain and subjective wellbeing (questionnaires) will also be examined. DISCUSSION: This study is designed to investigate the effects that PEA may have on pre-to post intervention changes in total body and regional lean muscle mass, strength, power, sleep, subjective wellbeing, and pain associated with resistance training and menstruation compared with the placebo condition. Unlike other NSAIDs and analgesics, which may inhibit muscle protein synthesis and training adaptations, PEA which provides analgesia via alternative mechanisms may provide an alternative pain management solution. It is therefore important to determine if this analgesic compound interferes with or enhances training adaptations so that athletes and active individuals can make an informed decision on their pain management strategies. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (ANZCTR: ACTRN12621001726842p).


Assuntos
Treinamento Resistido , Feminino , Humanos , Adulto , Adolescente , Adulto Jovem , Treinamento Resistido/métodos , Pisum sativum , Austrália , Força Muscular , Analgésicos/farmacologia , Dor , Suplementos Nutricionais/efeitos adversos , Anti-Inflamatórios não Esteroides/efeitos adversos , Músculo Esquelético , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Artigo em Inglês | MEDLINE | ID: mdl-28719997

RESUMO

BACKGROUND: Care for people with amyotrophic lateral sclerosis (ALS) has altered at King's College Hospital over the last 20 years. The clinic has been a multidisciplinary, specialist, tertiary referral centre since 1995 with a large team with integrated palliative and respiratory care since 2006. We hypothesised that these changes would improve survival. METHODS: In this retrospective observational study, patients diagnosed with El Escorial definite, probable and possible ALS between 1995-1998 and 2008-2011 were followed up. The primary outcome measure was a chi-square test for the proportion of each cohort surviving. Kaplan-Meier survival analysis and Cox multivariate regression were secondary analyses. RESULTS: There was low reporting of some interventions. Five hundred and forty-seven people were included. Survival between the cohorts was significantly different (p = 0.022) with a higher proportion surviving during 2008-2011. Survival time was 21.6 (95% CI 19.2-24.0) months in the 2008-2011 cohort compared to 19.2 years (15.6-21.6) in the 1995-1998 cohort (log rank p = 0.018). Four hundred and ninety-three cases were included in the Cox regression. Diagnostic cohort was a significant predictor variable (HR 0.79 (0.64-0.97) p = 0.023). CONCLUSIONS: These results support the hypothesis that integrated specialist clinics with multidisciplinary input improve survival in ALS.


Assuntos
Esclerose Lateral Amiotrófica/mortalidade , Esclerose Lateral Amiotrófica/enfermagem , Prestação Integrada de Cuidados de Saúde/estatística & dados numéricos , Equipe de Assistência ao Paciente/estatística & dados numéricos , Modelos de Riscos Proporcionais , Sistema de Registros , Estudos de Coortes , Feminino , Humanos , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Análise de Sobrevida
4.
Exp Gerontol ; 50: 95-105, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24316034

RESUMO

Panax ginseng has been used in traditional Chinese medicine for centuries. Among its various benefits is a pluripotent targeting of the various events involved in neuronal cell death. This includes anti-inflammatory, anti-oxidant, and anti-apoptotic effects. Indeed, ginseng extract and its individual ginsenosides have been demonstrated to influence a number of biochemical markers implicated in Parkinson's disease (PD) pathogenesis. We have reported previously that administration of the ginseng extract, G115, afforded robust neuroprotection in two rodent models of PD. However, these traditional rodent models are acute in nature and do accurately recapitulate the progressive nature of the disease. Chronic exposure to the dietary phytosterol glucoside, ß-sitosterol ß-d-glucoside (BSSG) triggers the progressive development of neurological deficits, with behavioral and cellular features that closely approximate those observed in PD patients. Clinical signs and histopathology continue to develop for several months following cessation of exposure to the neurotoxic insult. Here, we utilized this model to further characterize the neuroprotective effects of the ginseng extract, G115. Oral administration of this extract significantly reduced dopaminergic cell loss, microgliosis, and accumulation of α-synuclein aggregates. Further, G115 administration fully prevented the development of locomotor deficits, in the form of reduced locomotor activity and coordination. These results suggest that ginseng extract may be a potential neuroprotective therapy for the treatment of PD.


Assuntos
Fármacos Neuroprotetores/uso terapêutico , Panax , Doença de Parkinson Secundária/prevenção & controle , Fitoterapia/métodos , Animais , Morte Celular/efeitos dos fármacos , Modelos Animais de Doenças , Progressão da Doença , Avaliação Pré-Clínica de Medicamentos/métodos , Encefalite/induzido quimicamente , Encefalite/prevenção & controle , Feminino , Transtornos Neurológicos da Marcha/induzido quimicamente , Transtornos Neurológicos da Marcha/prevenção & controle , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/metabolismo , Doença de Parkinson Secundária/patologia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Sprague-Dawley , Sitosteroides , Substância Negra/patologia , alfa-Sinucleína/metabolismo
5.
Sci Transl Med ; 5(188): 188le2, 2013 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-23740897

RESUMO

Egawa et al. recently showed the value of patient-specific induced pluripotent stem cells (iPSCs) for modeling amyotrophic lateral sclerosis in vitro. Their study and our work highlight the need for complementary assays to detect small, but potentially important, phenotypic differences between control iPSC lines and those carrying disease mutations.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Avaliação Pré-Clínica de Medicamentos/métodos , Células-Tronco Pluripotentes Induzidas/citologia , Neurônios Motores/citologia , Humanos
6.
Commun Integr Biol ; 6(6): e26369, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24505503

RESUMO

Concerns about aluminum (Al) exposure in the human diet have persisted for one century. We suggest that continued research would benefit from better reporting of environmental factors that are known to influence Al accumulation in plant organs that are consumed, focusing on subsets of the general public that exhibit the highest risk for neuropathological responses, increased evaluation of commercial processing procedures that may concentrate Al or other toxic substances, and designing studies with low dose, chronic exposure rather than further study of acute, brief exposure.

7.
J Inorg Biochem ; 105(11): 1489-99, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22099159

RESUMO

Autism spectrum disorders (ASD) are serious multisystem developmental disorders and an urgent global public health concern. Dysfunctional immunity and impaired brain function are core deficits in ASD. Aluminum (Al), the most commonly used vaccine adjuvant, is a demonstrated neurotoxin and a strong immune stimulator. Hence, adjuvant Al has the potential to induce neuroimmune disorders. When assessing adjuvant toxicity in children, two key points ought to be considered: (i) children should not be viewed as "small adults" as their unique physiology makes them much more vulnerable to toxic insults; and (ii) if exposure to Al from only few vaccines can lead to cognitive impairment and autoimmunity in adults, is it unreasonable to question whether the current pediatric schedules, often containing 18 Al adjuvanted vaccines, are safe for children? By applying Hill's criteria for establishing causality between exposure and outcome we investigated whether exposure to Al from vaccines could be contributing to the rise in ASD prevalence in the Western world. Our results show that: (i) children from countries with the highest ASD prevalence appear to have the highest exposure to Al from vaccines; (ii) the increase in exposure to Al adjuvants significantly correlates with the increase in ASD prevalence in the United States observed over the last two decades (Pearson r=0.92, p<0.0001); and (iii) a significant correlation exists between the amounts of Al administered to preschool children and the current prevalence of ASD in seven Western countries, particularly at 3-4 months of age (Pearson r=0.89-0.94, p=0.0018-0.0248). The application of the Hill's criteria to these data indicates that the correlation between Al in vaccines and ASD may be causal. Because children represent a fraction of the population most at risk for complications following exposure to Al, a more rigorous evaluation of Al adjuvant safety seems warranted.


Assuntos
Adjuvantes Imunológicos/efeitos adversos , Hidróxido de Alumínio/efeitos adversos , Transtornos Globais do Desenvolvimento Infantil/induzido quimicamente , Compostos de Alúmen/efeitos adversos , Compostos de Alumínio/efeitos adversos , Austrália/epidemiologia , Canadá/epidemiologia , Criança , Transtornos Globais do Desenvolvimento Infantil/epidemiologia , Pré-Escolar , Finlândia/epidemiologia , Humanos , Islândia/epidemiologia , Lactente , Recém-Nascido , Fosfatos/efeitos adversos , Prevalência , Suécia/epidemiologia , Reino Unido/epidemiologia , Estados Unidos/epidemiologia
8.
Ann Neurol ; 68(1): 70-80, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20582986

RESUMO

OBJECTIVE: Exposure to a number of drugs, chemicals, or environmental factors can cause parkinsonism. Epidemiologic evidence supports a causal link between the consumption of flour made from the washed seeds of the plant Cycas micronesica by the Chamorro population of Guam and the development of amyotrophic lateral sclerosis/parkinsonism dementia complex. METHODS: We now report that consumption of washed cycad flour pellets by Sprague-Dawley male rats induces progressive parkinsonism. RESULTS: Cycad-fed rats displayed motor abnormalities after 2 to 3 months of feeding such as spontaneous unilateral rotation, shuffling gait, and stereotypy. Histological and biochemical examination of brains from cycad-fed rats revealed an initial decrease in the levels of dopamine and its metabolites in the striatum (STR), followed by neurodegeneration of dopaminergic (DAergic) cell bodies in the substantia nigra (SN) pars compacta (SNc). alpha-Synuclein (alpha-syn; proteinase K-resistant) and ubiquitin aggregates were found in the DAergic neurons of the SNc and neurites in the STR. In addition, we identified alpha-syn aggregates in neurons of the locus coeruleus and cingulate cortex. No loss of motor neurons in the spinal cord was found after chronic consumption of cycad flour. In an organotypic slice culture of the rat SN and the striatum, an organic extract of cycad causes a selective loss of dopamine neurons and alpha-syn aggregates in the SN. INTERPRETATION: Cycad-fed rats exhibit progressive behavioral, biochemical, and histological hallmarks of parkinsonism, coupled with a lack of fatality.


Assuntos
Cycas/toxicidade , Neurotoxinas/toxicidade , Transtornos Parkinsonianos/etiologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Dieta , Modelos Animais de Doenças , Progressão da Doença , Discinesias/etiologia , Discinesias/metabolismo , Discinesias/patologia , Farinha/toxicidade , Técnicas In Vitro , Masculino , Degeneração Neural/etiologia , Degeneração Neural/metabolismo , Degeneração Neural/patologia , Neurônios/metabolismo , Neurônios/patologia , Neurotoxinas/administração & dosagem , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/patologia , Extratos Vegetais/toxicidade , Ratos , Ratos Sprague-Dawley , Medula Espinal/metabolismo , Medula Espinal/patologia
9.
J Inorg Biochem ; 103(11): 1555-62, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19740540

RESUMO

Gulf War Syndrome is a multi-system disorder afflicting many veterans of Western armies in the 1990-1991 Gulf War. A number of those afflicted may show neurological deficits including various cognitive dysfunctions and motor neuron disease, the latter expression virtually indistinguishable from classical amyotrophic lateral sclerosis (ALS) except for the age of onset. This ALS "cluster" represents the second such ALS cluster described in the literature to date. Possible causes of GWS include several of the adjuvants in the anthrax vaccine and others. The most likely culprit appears to be aluminum hydroxide. In an initial series of experiments, we examined the potential toxicity of aluminum hydroxide in male, outbred CD-1 mice injected subcutaneously in two equivalent-to-human doses. After sacrifice, spinal cord and motor cortex samples were examined by immunohistochemistry. Aluminum-treated mice showed significantly increased apoptosis of motor neurons and increases in reactive astrocytes and microglial proliferation within the spinal cord and cortex. Morin stain detected the presence of aluminum in the cytoplasm of motor neurons with some neurons also testing positive for the presence of hyper-phosphorylated tau protein, a pathological hallmark of various neurological diseases, including Alzheimer's disease and frontotemporal dementia. A second series of experiments was conducted on mice injected with six doses of aluminum hydroxide. Behavioural analyses in these mice revealed significant impairments in a number of motor functions as well as diminished spatial memory capacity. The demonstrated neurotoxicity of aluminum hydroxide and its relative ubiquity as an adjuvant suggest that greater scrutiny by the scientific community is warranted.


Assuntos
Adjuvantes Imunológicos/toxicidade , Hidróxido de Alumínio/toxicidade , Doença dos Neurônios Motores/induzido quimicamente , Neurônios Motores/efeitos dos fármacos , Degeneração Neural/induzido quimicamente , Adjuvantes Imunológicos/administração & dosagem , Hidróxido de Alumínio/administração & dosagem , Animais , Vacinas contra Antraz/administração & dosagem , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Colina O-Acetiltransferase/efeitos dos fármacos , Colina O-Acetiltransferase/metabolismo , Proteína Glial Fibrilar Ácida , Humanos , Injeções Subcutâneas , Vértebras Lombares/efeitos dos fármacos , Vértebras Lombares/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Camundongos , Doença dos Neurônios Motores/metabolismo , Doença dos Neurônios Motores/psicologia , Neurônios Motores/metabolismo , Degeneração Neural/metabolismo , Proteínas do Tecido Nervoso/agonistas , Proteínas do Tecido Nervoso/metabolismo , Proteínas tau/metabolismo
11.
Amyotroph Lateral Scler ; 8(6): 343-7, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18033592

RESUMO

Patients homozygous for the D90A mutation of the SOD1 gene (homD90A) demonstrate markedly slower progression of disease than those patients with sporadic ALS (SALS). PET studies have demonstrated a different cortical vulnerability in the two groups, reflected also in neurophysiological studies showing reduced cortical excitability in homD90A. Voxel-based morphometric analysis of magnetic resonance images (MRIs) enables the detection of regional differences in grey matter volume, and can be used to localize cortical atrophy in vivo. In this study, segmented, spatially normalized, modulated and smoothed grey matter portions of the MRIs from 23 SALS and seven homD90A patients with similar disability, were compared with those from 28 healthy control subjects. The SALS group showed bilateral areas of atrophy mainly confined to motor and pre-motor cortices. Cortical changes in the homD90A group were more pronounced within the frontal lobes when both were compared with healthy controls. This study provides further evidence for a different pattern of cortical neuronal vulnerability in homD90A versus SALS patients that may provide insight as to their slower rate of disease progression.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/genética , Córtex Cerebral/patologia , Imageamento por Ressonância Magnética , Mutação , Superóxido Dismutase/genética , Adulto , Idoso , Esclerose Lateral Amiotrófica/fisiopatologia , Atrofia , Feminino , Lobo Frontal/patologia , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Superóxido Dismutase-1
12.
Proc Natl Acad Sci U S A ; 103(9): 3153-8, 2006 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-16492761

RESUMO

Rapid quantitative methods for characterizing small molecules, peptides, proteins, or RNAs in a broad array of cellular assays would allow one to discover new biological activities associated with these molecules and also provide a more comprehensive profile of drug candidates early in the drug development process. Here we describe a robotic system, termed the automated compound profiler, capable of both propagating a large number of cell lines in parallel and assaying large collections of molecules simultaneously against a matrix of cellular assays in a highly reproducible manner. To illustrate its utility, we have characterized a set of 1,400 kinase inhibitors in a panel of 35 activated tyrosine-kinase-dependent cellular assays in dose-response format in a single experiment. Analysis of the resulting multidimensional dataset revealed subclusters of both inhibitors and kinases with closely correlated activities. The approach also identified activities for the p38 inhibitor BIRB796 and the dual src/abl inhibitor BMS-354825 and exposed the expected side activities for Glivec/STI571, including cellular inhibition of c-kit and platelet-derived growth factor receptor. This methodology provides a powerful tool for unraveling the cellular biology and molecular pharmacology of both naturally occurring and synthetic chemical diversity.


Assuntos
Fosfotransferases/antagonistas & inibidores , Fosfotransferases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Robótica/métodos , Animais , Automação , Linhagem Celular , Bases de Dados Factuais , Avaliação Pré-Clínica de Medicamentos/métodos , Camundongos , Fosfotransferases/genética , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/isolamento & purificação , Reprodutibilidade dos Testes , Relação Estrutura-Atividade , Fatores de Tempo
13.
Artigo em Inglês | MEDLINE | ID: mdl-15320801

RESUMO

Phytosterols and omega-3 fatty acids (n-3) are natural food ingredients with potential cardiovascular benefits. Phytosterols inhibit cholesterol absorption, thereby reducing total cholesterol (TC) and LDL-cholesterol levels. Numerous clinical studies have shown that a daily intake of 1.5-2.0 g of phytosterols can result in a 10-15 % reduction in LDL levels, while consumption of n-3 is associated with a significant reduction in plasma triglyceride (TG) concentrations. Furthermore, n-3 may also beneficially modify a number of other risk factors of coronary heart disease (CHD). Thus, it is reasonable to suggest that combination of phytosterols and n-3 may further reduce cardiovascular risk factors. Esterification of phytosterols with non-n-3 fatty acids has substantially improved their incorporation into a variety of foods without affecting the efficacy of phytosterols. Therefore, it is assumed that esterification of phytosterols with n-3 may have advantages for both food industry and health. Evidence suggests that this combination is effective in reducing the levels of several cardiovascular risk factors including TC and TG concentrations, pro-aggregatory factors, arrhythmic eicosanoid and thromboxane A2 levels. In this mini-review, we have critically reviewed and summarized data from clinical and animal studies in which phytosterols and n-3, alone or in combination, were used. We have also provided information on structure-function relationship for these two natural compounds. Biological properties of several phytosterol derivatives including phytosterol-glucoside have been also discussed. Although the animal studies are supportive of this combination therapy, human studies are needed to address its long term effects.


Assuntos
Cardiotônicos/uso terapêutico , Doença das Coronárias/prevenção & controle , Ácidos Graxos Ômega-3/uso terapêutico , Fitosteróis/uso terapêutico , Animais , Anticolesterolemiantes/química , Anticolesterolemiantes/farmacologia , Anticolesterolemiantes/uso terapêutico , Cardiotônicos/química , Cardiotônicos/farmacologia , Ensaios Clínicos como Assunto , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Ácidos Graxos Ômega-3/química , Ácidos Graxos Ômega-3/farmacologia , Humanos , Fitosteróis/química , Fitosteróis/farmacologia , Relação Estrutura-Atividade
14.
Neuromolecular Med ; 3(2): 105-18, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12728193

RESUMO

Glutamate transporter proteins appear crucial to controlling levels of glutamate in the central nervous system (CNS). Abnormal and/or decreased levels of various transporters have been observed in amyotrophic lateral sclerosis (ALS) and Alzheimer's disease (AD) and in other neurological disorders. We have assessed glutamate transporter (GLT-1/EAAT2) levels in mice fed washed cycad flour containing a suspected neurotoxin that induces features resembling the Guamanian disorder, ALS-PDC. Down-regulation of glutamate transporter subtypes was detected by immunohistology using antibodies specific for two glial glutamate transporter splice variants (GLT-1alpha and GLT-1B). Immunohistology showed a "patchy" loss of antibody label with the patches centered on blood vessels. Computer densitometry showed significantly decreased GLT-1alpha levels in the spinal cord and primary somatosensory cortex of cycad-fed mice. GLT-1B levels were significantly decreased in the spinal cord, in the motor, somatosensory, and piriform cortices, and in the striatum. Western blots showed a 40% decrease in frontal motor cortex and lumbar spinal cord of cycad-fed mice that appeared to be phosphorylation-dependent. Receptor-binding assays showed decreased NMDA and AMPA receptor levels and increased GABAA receptor levels in cycad-fed mice cortex. These receptor data are consistent with an increased level of extracellular glutamate. The generalized decrease in GLT-1, decreased excitatory amino acid receptor levels, and increased GABAA receptor levels may reflect an early glutamate-mediated excitotoxicity following cycad exposure. Deciphering the series of events leading to neurodegeneration in cycad-fed animals may provide clues leading to therapeutic approaches to halt the early stages of disease progression.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Sistema Nervoso Central/metabolismo , Regulação para Baixo/fisiologia , Transportador 2 de Aminoácido Excitatório/metabolismo , Neuroglia/metabolismo , Esclerose Lateral Amiotrófica/patologia , Esclerose Lateral Amiotrófica/fisiopatologia , Animais , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/metabolismo , Sistema Nervoso Central/patologia , Sistema Nervoso Central/fisiopatologia , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Transportador 2 de Aminoácido Excitatório/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos , Neuroglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurotoxinas/toxicidade , Extratos Vegetais/toxicidade , Isoformas de Proteínas/efeitos dos fármacos , Isoformas de Proteínas/metabolismo , Receptores de GABA-A/efeitos dos fármacos , Receptores de GABA-A/metabolismo , Receptores de Glutamato/efeitos dos fármacos , Receptores de Glutamato/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia
15.
Neuromolecular Med ; 1(3): 207-21, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12095162

RESUMO

Consumption of cycad seed products (Cycas circinalis) is one of the strongest epidemiological links to the Guamian neurological disorder amyotrophic lateral sclerosis-parkinsonism-dementia complex (ALS-PDC), however, the putative toxin which causes neurodegeneration has never been identified definitively. To reexamine this issue, 6-7-mo-old, male CD-1 mice were assessed for motor and cognitive behaviours during and following feeding with pellets made from washed cycad flour. Cycad-fed animals showed early evidence of progressive motor and cognitive dysfunctions. Neurodegeneration measured using TUNEL and caspase-3 labeling was found in neocortex, various hippocampal fields, substantia nigra, olfactory bulb, and spinal cord. In vitro studies using rat neocortex have identified toxic compounds in washed cycad flour that induce depolarizing field potentials and lead to release of lactate dehydrogenase (LDH), both blocked by AP5. High-performance liquid chromatography (HPLC)/mass spectrometry of cycad flour samples failed to show appreciable amounts of other known cycad toxins, cycasin, MAM, or BMAA; only trace amounts of BOAA were present. Isolation procedures employing these techniques identified the most toxic component as beta-sitosterol beta-D-glucoside (BSSG). The present data suggest that a neurotoxin, or a toxic metabolite, not previously identified in cycad, is able to gain access to central nervous system (CNS) resulting in neurodegeneration of specific neural populations and in motor and cognitive dysfunctions. These data are consistent with a number of major features of ALS-PDC in humans.


Assuntos
Esclerose Lateral Amiotrófica/induzido quimicamente , Sistema Nervoso Central/efeitos dos fármacos , Cycas/química , Neurônios/efeitos dos fármacos , Neurotoxinas/toxicidade , Extratos Vegetais/toxicidade , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/fisiopatologia , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Sistema Nervoso Central/patologia , Sistema Nervoso Central/fisiopatologia , Coxeadura Animal/induzido quimicamente , Coxeadura Animal/patologia , Coxeadura Animal/fisiopatologia , Masculino , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/patologia , Transtornos da Memória/fisiopatologia , Camundongos , Camundongos Endogâmicos , Neurônios/metabolismo , Neurônios/patologia , Ratos , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia
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