RESUMO
Algunos investigadores señalan la estrecha interrelación entre el desarrollo y funcionamiento de los linfocitos T con la actividad de la adenosina desaminasa (ADA). Trabajos previos de nuestro grupo, en modelos experimentales, demostraron que el estrés nutricional causado por la distorsión de nutrientes en la dieta provoca incremento en la actividad de la ADA en timo de rata. Se demostró aumento en la actividad de esta enzima en suero de pacientes con enfermedades que comprometen los mecanismos de defensa. Se analizó si la actividad de ADA sérica podría considerarse parámetro bioquímico funcional en el seguimiento de poblaciones en riesgo nutricional. Para ello se la estudió en suero de individuos, con compromiso del estado nutricional evaluado a través de diferentes indicadores, en diferentes situaciones fisiopatológicas. Se estudiaron mujeres con anorexia nerviosa; escolares obesos y niños con fibrosis quística. Los valores de cada grupo fueron comparados con los obtenidos en individuos sanos de igual edad (C). Los resultados muestran un incremento en la actividad de ADA estadísticamente significativo con respecto a C. El análisis integral refuerza la hipótesis de proponer la determinación en la actividad sérica de ADA como un indicador funcional relacionado con los mecanismos de defensa en los estudios de nutrición.(AU)
Assuntos
Humanos , Masculino , Criança , Feminino , Adenosina Desaminase/análise , Distúrbios Nutricionais/diagnóstico , Distúrbios Nutricionais/enzimologia , Anorexia Nervosa , Obesidade , Fibrose CísticaRESUMO
Algunos investigadores señalan la estrecha interrelación entre el desarrollo y funcionamiento de los linfocitos T con la actividad de la adenosina desaminasa (ADA). Trabajos previos de nuestro grupo, en modelos experimentales, demostraron que el estrés nutricional causado por la distorsión de nutrientes en la dieta provoca incremento en la actividad de la ADA en timo de rata. Se demostró aumento en la actividad de esta enzima en suero de pacientes con enfermedades que comprometen los mecanismos de defensa. Se analizó si la actividad de ADA sérica podría considerarse parámetro bioquímico funcional en el seguimiento de poblaciones en riesgo nutricional. Para ello se la estudió en suero de individuos, con compromiso del estado nutricional evaluado a través de diferentes indicadores, en diferentes situaciones fisiopatológicas. Se estudiaron mujeres con anorexia nerviosa; escolares obesos y niños con fibrosis quística. Los valores de cada grupo fueron comparados con los obtenidos en individuos sanos de igual edad (C). Los resultados muestran un incremento en la actividad de ADA estadísticamente significativo con respecto a C. El análisis integral refuerza la hipótesis de proponer la determinación en la actividad sérica de ADA como un indicador funcional relacionado con los mecanismos de defensa en los estudios de nutrición.
Assuntos
Humanos , Masculino , Criança , Feminino , Adenosina Desaminase/análise , Anorexia Nervosa , Fibrose Cística , Obesidade , Distúrbios Nutricionais/diagnóstico , Distúrbios Nutricionais/enzimologiaRESUMO
We investigated the histochemical positivity to NADPH-diaphorase, which reveals nitric oxide synthase activity, in area 17 of rats malnourished early in life, both in the post-weaning period (group M1), and in adulthood after nutritional recovering (group M2). Control pups (C1 and C2 groups) received ad libitum after weaning the same diets as their mothers. Rats of group M2 were nutritionally recovered by receiving the control diet from post-natal day 42 until adulthood. Aldehyde-fixed sections (200-microm thick) through area 17 were processed for NADPH-diaphorase histochemistry following the malic enzyme indirect method. The features of NADPH-diaphorase-containing neurons of area 17 of malnourished young (M1) and adult (M2) rats were analyzed quantitatively in comparison to the matched groups C1 and C2. Permanent changes, represented by increase in the density and dendritic field areas of NADPH-diaphorase-positive cells, and transitory ones, represented by decreased values of soma areas, were observed in area 17 of the M1 and M2 cases. However, some other features, such as dendritic branch angle and number of dendrites per cell in the gray matter, remained unchanged after malnutrition. Thus, the findings indicate a possible relationship between early malnutrition and alterations in nitric oxide synthase-containing cells in the visual cortex. Physiological implications of these data may be related to synaptic plasticity and refinement of developmental brain circuits.
Assuntos
Tamanho Celular/fisiologia , NADPH Desidrogenase/metabolismo , Neurônios/patologia , Óxido Nítrico Sintase/metabolismo , Distúrbios Nutricionais/complicações , Córtex Visual/anormalidades , Córtex Visual/crescimento & desenvolvimento , Fatores Etários , Animais , Animais Recém-Nascidos/anormalidades , Animais Recém-Nascidos/metabolismo , Peso Corporal/fisiologia , Contagem de Células , Dendritos/enzimologia , Dendritos/patologia , Feminino , Alimentos Formulados/efeitos adversos , Plasticidade Neuronal/fisiologia , Neurônios/enzimologia , Distúrbios Nutricionais/enzimologia , Distúrbios Nutricionais/patologia , Gravidez , Ratos , Ratos Wistar , Recuperação de Função Fisiológica/fisiologiaRESUMO
BACKGROUND/AIMS: Undernutrition reduces the hypothalamic ganglioside concentration. This may be attributed to some modifications in the contents of precursors of sphingolipid biosynthesis in undernourished rats. The present study evaluated the serine palmitoyl transferase activity (SPT; EC 2.3.1.50) during the development of the rat hypothalamus. This work also shows the L-[3-(14)C]serine metabolic labeling of hypothalamic sphingolipids in normal and undernourished rats at weaning. METHODS: The SPT activity was determined in microsomal fractions obtained from the hypothalamus of normal rats (diet: 25% protein) and pre- and postnatally undernourished rats (diet: 8% protein since pregnancy) at 21 days of gestational age and at 7, 14, and 21 days of postnatal life. RESULTS: The enzymatic activity was lower in the hypothalamus of undernourished than in the hypothalamus of control rats since the 7th postnatal day. Incorporation of the precursor L-[3-(14)C]serine into sphingolipid fraction was lower in the hypothalamus of undernourished rats than in the hypothalamus of control rats on the 21st postnatal day which coincided with the age of the highest difference in SPT activity between normal and undernourished rats. CONCLUSION: These results indicate that undernutrition reduces the biosynthesis of the main sphingolipids during the period of brain growth spurt.
Assuntos
Aciltransferases/metabolismo , Antígenos CD , Hipotálamo/enzimologia , Hipotálamo/crescimento & desenvolvimento , Distúrbios Nutricionais/enzimologia , Animais , Autorradiografia , Radioisótopos de Carbono , Feminino , Gangliosídeos/metabolismo , Glucosilceramidas/metabolismo , Lactosilceramidas/metabolismo , Ratos , Ratos Wistar , Serina/metabolismo , Serina C-Palmitoiltransferase , Esfingomielinas/metabolismoRESUMO
Se estudió el efecto de la restricción alimentaria al 50 por ciento sobre enzimas que participan en el metabolismo reductivo del antichagásico benznidazol. Ratas machos recién destetadas fueron sometidas a restricción dietaria al 50 por ciento, durante 28 días, sacrificadas y medida la actividad nitrorreductásica in vitro, de enzimas microsomales hepáticas sobre benznidazol. La actividad nitrorreductásica sobre benznidazol fue significativamente menor en los animales con dieta restringida que en aquellos alimentados ad libitum
Assuntos
Masculino , Animais , Ratos , Doença de Chagas/tratamento farmacológico , Estado Nutricional/efeitos dos fármacos , Antiprotozoários/metabolismo , Biotransformação , Dieta/efeitos adversos , Imidazóis/metabolismo , Distúrbios Nutricionais/enzimologiaRESUMO
Se estudió el efecto de la restricción alimentaria al 50 por ciento sobre enzimas que participan en el metabolismo reductivo del antichagásico benznidazol. Ratas machos recién destetadas fueron sometidas a restricción dietaria al 50 por ciento, durante 28 días, sacrificadas y medida la actividad nitrorreductásica in vitro, de enzimas microsomales hepáticas sobre benznidazol. La actividad nitrorreductásica sobre benznidazol fue significativamente menor en los animales con dieta restringida que en aquellos alimentados ad libitum (AU)
Assuntos
Masculino , Animais , Ratos , Estudo Comparativo , Doença de Chagas/tratamento farmacológico , Estado Nutricional/efeitos dos fármacos , Distúrbios Nutricionais/enzimologia , Antiprotozoários/metabolismo , Dieta/efeitos adversos , Imidazóis/metabolismo , Biotransformação/efeitos dos fármacosRESUMO
The effects of undernutrition during early life on acetylcholinesterase (AChE) specific activity of cerebellum, hippocampus, hypothalamus and striatum were examined in rehabilitated adults rats. Undernourished rats were raised by dams maintained on a restricted food scheme from pup birth to pup weaning (day 31). The offspring were maintained on a restricted food schedule until day 38 when they started to have free access to food until 70-80 days of age. Control rats were raised by dams which had free access to food. The results showed that early malnutrition caused a significant increase in AChE specific activity in cerebellum (about 20%), striatum (about 40%), and hypothalamus (about 30%). No changes were found in the hippocampus. Undernutrition caused a significant increase in Vmax when compared to the control group without changes in Km both in cerebellum and striatum. These results suggest that early undernutrition changes AChE concentration in cerebellum and striatum and does not affect the affinity of the enzyme for the substrate.
Assuntos
Acetilcolinesterase/metabolismo , Encéfalo/enzimologia , Distúrbios Nutricionais/enzimologia , Animais , Feminino , Cinética , Masculino , Ratos , Ratos WistarRESUMO
The presence of activities that hydrolyse externally added ATP to adenosine in synaptosomal preparations from various sources is well demonstrated. The hydrolysis of ATP to AMP can be mediated either by the concerted action of enzymes or by an ATP-diphosphohydrolase (EC 3.6.1.5; apyrase). Undernutrition during the preweaning period can delay the development of several enzymes involved in the metabolism of neurotransmitters or neuronal function. In young rats, the presence of an apyrase in synaptosomal preparations from cerebral cortex was investigated. The results suggested that the hydrolysis of externally added ATP and ADP can be mediated by a single enzyme. The effects of preweaning undernutrition on the hydrolysis of ATP and ADP were also investigated. In weanling rats, previous undernutrition caused a decrease of about 20% in the hydrolysis of both substrates in synaptosomal fractions.
Assuntos
Animais Lactentes/metabolismo , Apirase/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Distúrbios Nutricionais/enzimologia , Monoéster Fosfórico Hidrolases/metabolismo , Sinaptossomos/enzimologia , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Peso Corporal , Encéfalo/anatomia & histologia , Hidrólise , Tamanho do Órgão , Ratos , Ratos Endogâmicos , DesmameRESUMO
The interaction between malnutrition and exposure to a mucosal damaging agent, difluoromethylornithine (DFMO), was examined by monitoring the small-intestinal changes in weanling rats. Malnutrition as induced by the expanded-litter method resulted in severe reduction in body weights in the expanded litters as compared to normal litters. Subsequent treatment of malnourished and well-nourished pups with DFMO for 7 days resulted in decreases in small-intestinal weights and enzyme contents. A 2 factors (well-nourished and malnourished) by 2 factors (DFMO-treated and nontreated) analysis of variance showed no interaction between malnutrition and DFMO treatment in terms of food intake, total mucosal protein, and contents of enterokinase, leucine aminopeptidase and sucrase. Very slight and insignificant interactions (p less than or equal to 0.2) were found for body weights, intestinal weights and total DNA content. Only one parameter studied, the maltase content, showed significant interaction between malnutrition and DFMO treatment (p less than 0.05). Three weeks after the withdrawal of DFMO, essentially all the changes caused by DFMO recovered. But those changes caused by malnutrition did not, such that the malnourished group, whether treated with DFMO or not, still remained significantly less than the control group in their small-intestinal parameters. Analysis of variance showed no interaction between malnutrition and DFMO treatment in the recovery phase. The results suggest that malnutrition is a more important factor in determining the intestinal damage and that malnutrition in the immediate postnatal period does not increase the sensitivity of the small intestine to the damaging effect of DFMO.
Assuntos
Eflornitina/toxicidade , Mucosa Intestinal/efeitos dos fármacos , Distúrbios Nutricionais/complicações , Animais , Animais Lactentes , Divisão Celular/efeitos dos fármacos , Feminino , Glicosídeo Hidrolases/metabolismo , Mucosa Intestinal/enzimologia , Mucosa Intestinal/patologia , Leucil Aminopeptidase/metabolismo , Masculino , Distúrbios Nutricionais/enzimologia , Fosfotransferases/metabolismo , Ratos , Ratos EndogâmicosRESUMO
We used a sensitive probe of pancreatic dysfunction, serum immunoreactive cationic trypsinogen, to study 50 infants and children with varying degrees of malnutrition. Patients were classified into subgroups according to the severity of malnutrition. Mean serum trypsinogen concentration was significantly elevated in 25 patients with "severe" malnutrition (77.4 +/- 42.0 ng/ml, P less than 0.001) and in 23 with "moderate" malnutrition (55.2 +/- 16.1 ng/ml, P less than 0.02) compared with the mean value (32.5 +/- 10.4 ng/ml) for well-nourished controls. The level of circulating trypsinogen tended to rise with increasing severity of malnutrition. There was no relationship between serum trypsinogen and other variables such as age, specific diagnosis, or mode of feeling. Elevated serum trypsinogen levels could not be attributed to renal disease or cystic fibrosis. In patients who showed an improvement in nutritional status, serum trypsinogen tended to revert toward normal. Elevated serum trypsinogen values in acutely malnourished infants and children may result from pancreatic acinar cell damage or regurgitation of enzymes from obstructed pancreatic ducts.
Assuntos
Distúrbios Nutricionais/enzimologia , Pâncreas/fisiopatologia , Tripsinogênio/sangue , Doença Aguda , Cátions , Pré-Escolar , Creatinina/sangue , Creatinina/urina , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Distúrbios Nutricionais/fisiopatologia , Pâncreas/enzimologia , Radioimunoensaio , Tripsinogênio/urinaRESUMO
Amylase activities were quantitated in secretions of marginally and severely malnourished Colombian children. In young children with a mean age of 21 months, the relative pancreatic and salivary amylase isozyme activities of urine were significantly changed in marginally malnourished children compared to normal children. There was a relative increase in salivary and decrease in pancreatic amylase activity in the undernourished children and total amylase activity was somewhat decreased. Amylase activity in saliva and tears was significantly lower in these malnourished children. Older children who were more severely malnourished had significantly lower amylase activity in their sera and tears. Thus marginal and severe malnutrition affects the production of amylase by the pancreas and salivary glands of young children distinctly. It significantly suppresses amylase activity in tears, saliva, and serum.
Assuntos
Amilases/metabolismo , Isoenzimas/metabolismo , Distúrbios Nutricionais/enzimologia , Pâncreas/enzimologia , Saliva/enzimologia , Aminopeptidases/metabolismo , Amilases/urina , Pré-Escolar , Colômbia , Feminino , Humanos , Lactente , Isoenzimas/urina , Masculino , Lágrimas/enzimologiaRESUMO
Pregnancies were compared in 18 Ecuadorian women of low socioeconomic status and 11 of high socioeconomic status. Objective evidence of malnutrition was demonstrable in virtually all of the women from the low socioeconomic group and in none from the high socioeconomic group. Birth weight and placental weight were significantly lower in the malnourished group. Nucleic acid and protein content of placentas were slightly lower and activity of alkaline ribonuclease was markedly elevated. The data reinforce animal studies and demonstrate for the first time in human subjects that alkaline RNase activity is increased in placentas from malnourished women. We suggest that activity of this enzyme in placenta may prove to be a useful marker of maternal and fetal nutritional status.
Assuntos
Distúrbios Nutricionais/enzimologia , Placenta/enzimologia , Complicações na Gravidez/enzimologia , Ribonucleases/metabolismo , Equador , Feminino , Humanos , Técnicas In Vitro , Gravidez , Fatores SocioeconômicosAssuntos
Dissacaridases/metabolismo , Doenças Fetais/enzimologia , Feto/enzimologia , Distúrbios Nutricionais/enzimologia , Animais , Modelos Animais de Doenças , Feminino , Feto/metabolismo , Mucosa Intestinal/enzimologia , Mucosa Intestinal/metabolismo , Masculino , Troca Materno-Fetal , Gravidez , RatosRESUMO
DNA polymerase activity has been measured in placentas of normal and protein-restricted rats and correlated with the mean percent daily increase in DNA. During normal placental growth, increases in DNA fell rapidly from 13 to 19 days and polymerase activity using denatured DNA template showed a similar pattern falling from values of 10,000 mumu mols dAMP incorporated per mg DNA at 12 days of gestation to 3,100 at 19 days. Protein restriction during gestation reduced placental DNA content after 14 days; by 19 days the DNA content was 81% of normal. The increase in DNA between 13 and 19 days in placentas of malnourished animals paralleled the normal but was significantly lower. Malnutrition markedly reduced enzyme activity at 12, 14, and 16 days; at 19 days, when DNA synthesis has normally ceased, values of DNA polymerase were not different in control and malnourished placentas. Thus DNA polymerase activity using denatured DNA as template, as measured in vitro, was an index of proliferative cell growth in both normal and malnourished placentas. Furthermore, the decrease in enzyme activity in malnourished samples preceded by at least two days any measurable decrease in total placenta DNA content. It is suggested that future clinical application of this technique may provide an index of nutritional status in "at risk" pregnancies.
Assuntos
DNA Nucleotidiltransferases/metabolismo , Distúrbios Nutricionais/enzimologia , Placenta/enzimologia , Complicações na Gravidez , Monofosfato de Adenosina/metabolismo , Animais , Caseínas , DNA/análise , DNA/biossíntese , Desoxirribonucleotídeos/análise , Proteínas Alimentares , Feminino , Glicerol/análise , Humanos , Troca Materno-Fetal , Desnaturação de Ácido Nucleico , Placenta/análise , Doenças Placentárias/enzimologia , Doenças Placentárias/etiologia , Gravidez , Coelhos , Ratos , Moldes GenéticosAssuntos
Aminoácidos/metabolismo , Fígado/enzimologia , Liases/metabolismo , Distúrbios Nutricionais/enzimologia , Adaptação Fisiológica , Peso Corporal , Dietoterapia , Edema/enzimologia , Feminino , Hepatomegalia/enzimologia , Humanos , Lactente , Jamaica , Masculino , Deficiência de Proteína/enzimologiaRESUMO
Aminoacid-activating enzymes and argininosuccinase were measured in liver-biopsy samples from twenty-two malnourished and recovering Jamaican infants. Aminoacid-activating-enzyme levels were increased initially and fell on recovery; argininosuccinase activity was low initially and rose on recovery. It is suggested that these changes are part of the adaptation which takes place in aminoacid metabolism in the malnourished state. (AU)