RESUMO
Malnutrition during the earliest stages of life may result in innumerable brain problems. Moreover, this condition could increase the chances of developing neurological diseases, such as epilepsy. We analyzed the effects of early-life malnutrition on susceptibility to epileptic seizures induced by the pilocarpine model of epilepsy. Wistar rat pups were kept on a starvation regimen from day 1 to day 21 after birth. At day 60, 16 animals (8 = well-nourished; 8 = malnourished) were exposed to the pilocarpine experimental model of epilepsy. Age-matched well-nourished (n = 8) and malnourished (n = 8) rats were used as controls. Animals were video-monitored over 9 weeks. The following behavioral parameters were evaluated: first seizure threshold (acute period of the pilocarpine model); status epilepticus (SE) latency; first spontaneous seizure latency (silent period), and spontaneous seizure frequency during the chronic phase. The cell and mossy fiber sprouting (MFS) density were evaluated in the hippocampal formation. Our results showed that the malnourished animals required a lower pilocarpine dose in order to develop SE (200 mg/kg), lower latency to reach SE, less time for the first spontaneous seizure and higher seizure frequency, when compared to well-nourished pilocarpine rats. Histopathological findings revealed a significant cell density reduction in the CA1 region and intense MFS among the malnourished animals. Our data indicate that early malnutrition greatly influences susceptibility to seizures and behavioral manifestations in adult life. These findings suggest that malnutrition in infancy reduces the threshold for epilepsy and promotes alterations in the brain that persist into adult life.
Assuntos
Epilepsia do Lobo Temporal/etiologia , Epilepsia do Lobo Temporal/patologia , Hipocampo/patologia , Desnutrição/complicações , Desnutrição/patologia , Animais , Animais Recém-Nascidos , Convulsivantes/toxicidade , Modelos Animais de Doenças , Humanos , Transtornos da Nutrição do Lactente/complicações , Transtornos da Nutrição do Lactente/patologia , Recém-Nascido , Fibras Musgosas Hipocampais/patologia , Pilocarpina/toxicidade , Ratos , Ratos WistarRESUMO
La desnutrición es un determinante crítico de la inmunocompetencia con alteraciones de la respuesta inmunitaria y de riesgo de enfermedad durante la edad pediátrica especialmente en los países en desarrollo. Los niños con malnutrición o desnutrición proteico-calórica muestran un aumento de su mortalidad y morbilidad debido principalmente a enfermedades infecciosas. Con la finalidad de investigar el comportamiento inmunológico en el desnutrido, se estudiaron en un lapso de año y medio, 12 desnutridos (5 kwashiorkor, 5 marasmáticos, 1 marasmo/kwashiorkor y 1 desnutrido moderado) de edades comprendidas entre 5 y 24 meses, sometidos a terapia nutricional en el servicio de recuperación nutricional (SERN) del Hospital Chinquinquirá de Maracaibo, Venezuela. Para ello se realizaron diferentes pruebas de laboratorio al momento del ingreso y a las 4 y 8 semanas de estar bajo terapia nutricional, se cuantificaron las inmunoglobulinas séricas (IgG, IgA e IgM), la IgA secretora, los componentes C3 y C4 del complemento, las subpoblaciones linfocitarias CD3, CD4 y CD8, se realizaron pruebas cutáneas de hipersensibilidad tardia y se determinaron anticuerpos (antinucleares, antitiroideos y factor reumatoide). Como grupo control se incluyeron 10 niños de igual edad y sexo. Se encontró que los valores de inmunoglobulinas séricas al ingreso, no difirieron significativamente del grupo control y que igualmente no mostraron variación a lo largo del estudio. Hubo valores muy bajos para la IgA secretora en la primera determinación, los cuales permanecieron por debajo del grupo control hasta el final del estudio. Se encontraron valores inferiores estadísticamente significativos para el complemento C3 pero no para el C4 y estos valores se normalizaron al final del estudio. Se encontró una disminución estadísticamente significativa en el porcentaje de las poblaciones linfocitarias CD4 y CD3 las cuales alcanzaron el valor normal antes de finalizar el estudio. Las pruebas cutáneas fueron positivas solo en dos pacientes. La investigación de anticuerpos fue negativa. Se concluye en este estudio que la competencia inmunitaria en el desnutrido se encuentra alterada especialmente para el C3, la IgA secretora y las poblaciones linfocitarias CD3 y CD4 y que estas alteraciones son reversibles en un tiempo variable para cada una de ellas
Assuntos
Lactente , Humanos , Masculino , Feminino , Desnutrição Proteico-Calórica/imunologia , Transtornos da Nutrição do Lactente/patologia , Kwashiorkor/patologia , Distúrbios Nutricionais/imunologia , Recuperação Nutricional/métodos , CriançaRESUMO
The development of moderate malnutrition and cell-mediated immune function was studied in 71 Colombian infants from birth through 2 yr of age. Based upon weight-for-age criteria 31 remained normal, 33 were classified as grade I, and seven were grade II malnourished at the end of their 2nd yr of life. Delayed hypersensitivity reactions to purified protein derivative were significantly reduced in all malnourished children 8 wk after Bacille Calmette-Guerin vaccination at birth, and also at 2 yr in the Grade II group. Nearly half of the latter group could not be sensitized to dinitrochlorobenzene at 2 yr of age. A 50% reduction in the blastogenic response of peripheral blood lymphocytes to phytohemagglutinin in vitro was detected in grade II children. Both mildly and moderately malnourished infants exhibited a significant reduction in tonsil size at 2 yr of age. These results indicate that a majority of newborns in this poor, urban setting will develop measurable malnutrition associated with impaired cell-mediated immune function before their 2nd birthday.
Assuntos
Imunidade Celular , Transtornos da Nutrição do Lactente/imunologia , Vacina BCG/uso terapêutico , Pré-Escolar , Colômbia , Feminino , Humanos , Imunização , Imunocompetência , Lactente , Transtornos da Nutrição do Lactente/classificação , Transtornos da Nutrição do Lactente/patologia , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Ativação Linfocitária , Masculino , Tonsila Palatina/patologia , Gravidez , Teste TuberculínicoRESUMO
1. The growth of muscle fibres was analysed by light microscopy in biopsies from subjects when malnourished, during nutritional rehabilitation, and after clinical recovery. 2. Muscle fibres from malnourished subjects were extremely atrophic (cross-sectional area, 110 micrometers2). The fibres doubled in size during the early period of rehabilitation. Growth of muscle fibres during later periods of rehabilitation occurred at a slower rate. 3. The absolute rates of change in fibre sizes differed considerably between subjects, but the rates of change relative to the rate of gain of total body-weight (expressed as % recovery or % expected weight-for height (Nelson, 1975)) were similar between subjects after the initial growth spurt. The pattern of recovery appeared to differ between older and younger subjects. 4. Fibre sizes correlated with body-weight but not with age in the malnourished subjects. A significant correlation between fibre areas and either weight or age was observed during rehabilitation and after clinical recovery. 5. Fibre sizes of clinically-recovered subjects (mean age, 13.8 months; weight, 8.7 kg) were only approximately 60% of that for a well-nourished 6-month-old control subject (6.4 kg). These results suggest that a longer period of time is required for fibres to reach their expected size. Therefore, when the child has regained body-weight to that of a normal child of the same height, his muscles have not yet recovered and his body composition is abnormal.