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1.
Int J Dev Neurosci ; 80(5): 369-379, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32379904

RESUMO

Maple Syrup Urine Disease (MSUD) is caused by a severe deficiency in the branched-chain ketoacid dehydrogenase complex activity. Patients MSUD accumulate the branched-chain amino acids leucine (Leu), isoleucine, valine in blood, and other tissues. Leu and/or their branched-chain α-keto acids are linked to neurological damage in MSUD. When immediately diagnosed and treated, patients develop normally. Inflammation in MSUD can elicit a metabolic decompensation crisis. There are few cases of pregnancy in MSUD women, and little is known about the effect of maternal hyperleucinemia on the neurodevelopment of their babies. During pregnancy, some intercurrences like maternal infection or inflammation may affect fetal development and are linked to neurologic diseases. Lipopolysaccharide is widely accepted as a model of maternal inflammation. We analyzed the effects of maternal hyperleucinemia and inflammation and the possible positive impact the use of ibuprofen in Wistar rats on a battery of physics (ear unfolding, hair growing, incisors eruption, eye-opening, and auditive channel opening) and neurological reflexes (palmar grasp, surface righting, negative geotaxis, air-righting, and auditory-startle response) maturation parameters in the offspring. Maternal hyperleucinemia and inflammation delayed some physical parameters and neurological reflexes, indicating that both situations may be harmful to fetuses, and ibuprofen reversed some settings.

2.
Metab Brain Dis ; 34(6): 1649-1660, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31352540

RESUMO

Phenylketonuria (PKU) is the most common inborn error of amino acid metabolism. Usually diagnosed within the first month of birth, it is essential that the patient strictly follow the dietary restriction of natural protein intake. Otherwise, PKU impacts the development of the brain severely and may result in microcephaly, epilepsy, motor deficits, intellectual disability, and psychiatric and behavioral disorders. The neuropathology associated with PKU includes defects of myelination, insufficient synthesis of monoamine neurotransmitters, amino acid imbalance across the blood-brain barrier, and involves intermediary metabolic pathways supporting energy homeostasis and antioxidant defenses in the brain. Considering that the production of reactive oxygen species (ROS) is inherent to energy metabolism, we investigated the association of creatine+pyruvate (Cr + Pyr), both energy substrates with antioxidants properties, as a possible treatment to mitigate oxidative stress and phosphotransfer network impairment elicited in the brain of young Wistar rats by chemically-induced PKU. We induced PKU through the administration of α-methyl-L-phenylalanine and phenylalanine for 7 days, with and without Cr + Pyr supplementation, until postpartum day 14. The cotreatment with Cr + Pyr administered concurrently with PKU induction prevented ROS formation and part of the alterations observed in antioxidants defenses and phosphotransfer network enzymes in the cerebral cortex, hippocampus, and cerebellum. If such prevention also occurs in PKU patients, supplementing the phenylalanine-restricted diet with antioxidants and energetic substrates might be beneficial to these patients.


Assuntos
Antioxidantes/farmacologia , Encéfalo/efeitos dos fármacos , Creatina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fenilcetonúrias/metabolismo , Ácido Pirúvico/farmacologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Modelos Animais de Doenças , Metabolismo Energético/efeitos dos fármacos , Fenilalanina/análogos & derivados , Fenilcetonúrias/induzido quimicamente , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
3.
Neurotox Res ; 32(4): 575-584, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28612295

RESUMO

Maple syrup urine disease is an autosomal metabolic disease caused by a deficiency of branched-chain α-keto acid dehydrogenase complex activity. In this disease occur the accumulation of the branched-chain amino acids leucine, isoleucine, and valine and their corresponding branched-chain α-keto acids in the tissues and body fluids. The affected patients may present psychomotor development delay and mental retardation. The pathophysiology of maple syrup urine disease is not entirely understood, but leucine seems to be the primary neurotoxic metabolite. Creatine and pyruvate are energetics and antioxidants substances. In this study, we investigated the effects of leucine administration and co-administration of creatine plus pyruvate on several parameters of oxidative stress and phosphoryl transfer network in cerebral cortex and hippocampus of Wistar rats treated from the 8th to the 21st postpartum day. Leucine induced oxidative stress and diminished the activities of pyruvate kinase, adenylate kinase, cytosolic and mitochondrial creatine kinase. Co-administration of creatine plus pyruvate prevented the alterations provoked by leucine administration on the oxidative stress and the enzymes of phosphoryltransfer network. These results indicate that chronic administration of leucine may stimulate oxidative stress and alters the enzymes of phosphoryltransfer network in the cerebral cortex and hippocampus of the rats. It is possible that these effects may contribute, along with other mechanisms, to the neurological dysfunction found in patients affected by maple syrup urine disease. In this case, it is possible that creatine plus pyruvate supplementation could benefit to the patients.


Assuntos
Creatina/farmacologia , Leucina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ácido Pirúvico/farmacologia , Aminoácidos de Cadeia Ramificada/metabolismo , Animais , Antioxidantes/farmacologia , Córtex Cerebral/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
4.
Metab Brain Dis ; 31(3): 529-37, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26573865

RESUMO

The aim of this study was to investigate the effects of phenylalanine on oxidative stress and some metabolic parameters in astrocyte cultures from newborn Wistar rats. Astrocytes were cultured under four conditions: control (0.4 mM phenylalanine concentration in the Dulbecco's Modified Eagle Medium (DMEM) solution), Phe addition to achieve 0.5, 1.0 or 1.5 mM final phenylalanine concentrations. After 72 h the astrocytes were separated for the biochemical measurements. Overall measure of mitochondrial function by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and cell viability measured by lactate dehydrogenase (LDH) assays indicated that phenylalanine induced cell damage at the three concentrations tested. The alteration on the various parameters of oxidative stress indicated that phenylalanine was able to induce free radicals production. Therefore, our results strongly suggest that Phe at concentrations usually found in PKU induces oxidative stress and consequently cell death in astrocytes cultures. Considering the importance of the astrocytes for brain function, it is possible that these astrocytes alterations may contribute to the brain damage found in PKU patients.


Assuntos
Astrócitos/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Degeneração Neural/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fenilalanina/farmacologia , Fenilcetonúrias/metabolismo , Adenilato Quinase/metabolismo , Animais , Astrócitos/metabolismo , Astrócitos/patologia , Células Cultivadas , Creatina Quinase/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Degeneração Neural/patologia , Fenilcetonúrias/patologia , Piruvato Quinase/metabolismo , Ratos , Ratos Wistar
5.
Phytother Res ; 23(6): 859-62, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19107736

RESUMO

Vimang is an aqueous extract of Mangifera indica L, used in Cuba for the treatment of immunopathological disorders. Increasing evidence from preclinical studies indicates that Vimang displays antioxidant, antiallergic, analgesic and antiinflammatory actions. The present study investigated the effects of systemic administration of Vimang on behavioural outcomes of neurological function in rats. A single oral administration of Vimang produced an impairment of short- and long-term retention of memory for aversive training when given either 1 h pretraining or immediately posttraining, but not 8 h posttraining. Vimang did not affect open field behaviour or habituation. The results indicate that Vimang might induce deficits of emotionally motivated memory without affecting nonassociative memory, locomotion, exploratory behaviour or anxiety.


Assuntos
Comportamento Animal/efeitos dos fármacos , Memória/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Habituação Psicofisiológica/efeitos dos fármacos , Masculino , Mangifera/química , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Wistar
6.
Neurochem Res ; 32(8): 1381-6, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17406984

RESUMO

Increasing evidence indicates that the gastrin-releasing peptide receptor (GRPR) is implicated in regulating synaptic plasticity and memory formation in the hippocampus and other brain areas. However, the molecular mechanisms underlying the memory-impairing effects of GRPR antagonism have remained unclear. Here we report that basic fibroblast growth factor (bFGF/FGF-2) rescues the memory impairment induced by GRPR antagonism in the rat dorsal hippocampus. The GRPR antagonist [D-Tpi(6), Leu(13) psi(CH(2)NH)-Leu(14)] bombesin (6-14) (RC-3095) at 1.0 microg impaired, whereas bFGF at 0.25 microg enhanced, 24 h retention of inhibitory avoidance (IA) when infused immediately after training into the CA1 hippocampal area in male rats. Coinfusion with an otherwise ineffective dose of bFGF blocked the memory-impairing effect of RC-3095. These findings suggest that the memory-impairing effects of GRPR antagonists might be partially mediated by an inhibition in the function and/or expression of neuronal bFGF or diminished activation of intracellular protein kinase pathways associated with bFGF signaling.


Assuntos
Fator 2 de Crescimento de Fibroblastos/metabolismo , Hipocampo/metabolismo , Transtornos da Memória/metabolismo , Fármacos Neuroprotetores/metabolismo , Receptores da Bombesina/antagonistas & inibidores , Animais , Comportamento Animal/fisiologia , Bombesina/análogos & derivados , Bombesina/metabolismo , Hipocampo/citologia , Masculino , Memória/fisiologia , Fragmentos de Peptídeos/metabolismo , Ratos , Ratos Wistar , Receptores da Bombesina/metabolismo
7.
Neuroimmunomodulation ; 13(3): 160-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17139191

RESUMO

BACKGROUND: Both endocrine and immune systems are continuously remodeled during aging. OBJECTIVE: Here, we investigated to what extent adrenal and somatosenescence are associated reciprocal changes in the immune system during strictly healthy aging. METHODS: Forty-six elderly subjects and 33 young adults were recruited according to the health criteria of the SENIEUR protocol. Peripheral blood mononuclear cells were isolated and stimulated in vitro with lipopolysaccharide or phytohemagglutinin to assess the production of immunoreactive growth hormone (GH). Peripheral sensitivity to steroids was assessed in vitro by dexamethasone-, cortisol- or dehydroepiandrosterone (DHEA)-induced inhibition of T-cell proliferation. DHEA and GH levels were measured by radioimmunoassays. RESULTS: Healthy elderly had lower salivary DHEA and serum GH levels (somatosenescence). They presented reduced T-cell sensitivity to dexamethasone but similar cellular sensitivities to cortisol and DHEA. Their cells produced similar levels of immunoreactive GH compared to the cells of young adults. CONCLUSIONS: These data indicate that healthy aging is associated with adrenal and somatosenescence as well as impaired neuroendocrine immunoregulation at the level of the lymphocyte. In addition, somatosenescence may not be associated with a reciprocal decline in immunoreactive GH.


Assuntos
Envelhecimento/imunologia , Hormônio do Crescimento Humano/biossíntese , Leucócitos Mononucleares/metabolismo , Neuroimunomodulação/fisiologia , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Área Sob a Curva , Proliferação de Células , Células Cultivadas , Desidroepiandrosterona/análise , Desidroepiandrosterona/metabolismo , Feminino , Glucocorticoides/metabolismo , Hormônio do Crescimento Humano/sangue , Humanos , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Saliva/química , Linfócitos T/metabolismo
9.
Mech Ageing Dev ; 124(8-9): 887-95, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14499493

RESUMO

Human ageing has been associated with immunological changes including blunted T-cell responses and increased production of pro-inflammatory cytokines. Here, we investigated the role of psychological and endocrine factors in the production of pro-inflammatory cytokines (tumor necrosis factor-alpha and interleukin (IL)-6) as well as soluble IL-2Ralpha, associated with T-cell activation. Forty-six elderly subjects (60-91 yrs) and 33 young adults (20-40 yrs) were recruited accordingly the SENIEUR protocol. The emotional status was measured by structured clinical interviews. Salivary cortisol levels (9, 12 and 22 h) and serum dehydroepiandrosterone (DHEA) were assessed by radioimmunoassays. The elderly were more stressed, depressed and anxious than the young subjects. Cortisol levels were increased whereas DHEA levels were significantly reduced in the elderly. Both groups showed equivalent production of pro-inflammatory cytokines as well as soluble IL-2Ralpha. Psychological scores were positively correlated to evening cortisol levels and negatively correlated to morning DHEA levels. No relationships were noted between psychological factors and cytokines studied. However, evening cortisol levels were found positively correlated to TNF-alpha and sIL-2Ralpha levels. These data indicate that healthy ageing is associated with significant distress and activation of the hypothalamic-pituitary-adrenal axis. Our data also suggest that there are complex psychoneuroendocrine relationships involved with cytokine production during ageing.


Assuntos
Envelhecimento/metabolismo , Envelhecimento/psicologia , Citocinas/biossíntese , Saúde Mental , Sistemas Neurossecretores/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Ansiedade/metabolismo , Células Cultivadas , Desidroepiandrosterona/sangue , Depressão/metabolismo , Feminino , Humanos , Hidrocortisona/metabolismo , Masculino , Pessoa de Meia-Idade , Saliva/metabolismo , Estresse Psicológico/metabolismo
10.
Rev. med. PUCRS ; 12(3): 226-231, jul.-set. 2002. ilus, graf
Artigo em Português | LILACS | ID: lil-360275

RESUMO

Objetivos: Padronizar de um ensaio colorimétrico quantitativo para avaliação da proliferação linfocitária humana e sensibilidade a glicocorticóides IN VITRO. Material e Métodos: Sangue periférico foi coletado de adultos saudáveis, células mononucleares foram isoladas por um gradiente de densidade e cultivadas por 36 H (a 37 graus e 5 por cento de gás carbônico) na prsença de fitohemaglutinina (PHA), mitógeno de células T, e glicocorticóides (dexametasona, cortisol e metilprenisolona). O presente estudo apresenta a padronização da etapa de revelação desses ensaios, utilizando o sal de tetrazólio (MTT; 3-(4,5-dimetiltiazol-2-il)-2,5-difenil brometo tetrazólico) como marcador. Resulatdos: A padronização do ensaio de proliferação estabeleceu as seguintes condições ótimas de cultura: 1,5x10na quinta células/poço, 5mg/mL de MTT e 1 por cento de PHA. Todos os glicocorticóides testados apresentram um efeito supressor dose-dependente da proliferação, com máxima supressão a 10 na quinta negativo M. Conclusões: As principais vantagens do ensaio colorimétrico são sua rapidez, precisão e dispensabilidade de radioisótopos. Esses ensaios estão sendo utilizados para a avliação da imunidade celular nos idosos bem como em pacientes com câncer e doenças respiratórias.


Assuntos
Glucocorticoides , Ativação Linfocitária , Sais de Tetrazólio , Dexametasona , Colorimetria
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