RESUMO
We have previously described a theoretical model in humans, called "Similarities in the Inequalities", in which extremely unequal social backgrounds coexist in a complex scenario promoting similar health outcomes in adulthood. Based on the potential applicability of and to further explore the "similarities in the inequalities" phenomenon, this study used a rat model to investigate the effect of different nutritional backgrounds during gestation on the willingness of offspring to engage in physical activity in adulthood. Sprague-Dawley rats were time mated and randomly allocated to one of three dietary groups: Control (Adlib), receiving standard laboratory chow ad libitum; 50% food restricted (FR), receiving 50% of the ad libitum-fed dam's habitual intake; or high-fat diet (HF), receiving a diet containing 23% fat. The diets were provided from day 10 of pregnancy until weaning. Within 24 hours of birth, pups were cross-fostered to other dams, forming the following groups: Adlib_Adlib, FR_Adlib, and HF_Adlib. Maternal chow consumption and weight gain, and offspring birth weight, growth, physical activity (one week of free exercise in running wheels), abdominal adiposity and biochemical data were evaluated. Western blot was performed to assess D2 receptors in the dorsal striatum. The "similarities in the inequalities" effect was observed on birth weight (both FR and HF groups were smaller than the Adlib group at birth) and physical activity (both FR_Adlib and HF_Adlib groups were different from the Adlib_Adlib group, with less active males and more active females). Our findings contribute to the view that health inequalities in fetal life may program the health outcomes manifested in offspring adult life (such as altered physical activity and metabolic parameters), probably through different biological mechanisms.
Assuntos
Peso ao Nascer , Restrição Calórica/efeitos adversos , Dieta Hiperlipídica/efeitos adversos , Fenômenos Fisiológicos da Nutrição Materna , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Gordura Abdominal/metabolismo , Animais , Feminino , Desenvolvimento Fetal , Comportamentos Relacionados com a Saúde , Masculino , Modelos Animais , Neostriado/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Dopamina D2/metabolismo , Fatores Socioeconômicos , Aumento de PesoAssuntos
Feto/fisiologia , Preferências Alimentares , Recém-Nascido/fisiologia , Mães , Paladar , Animais , Feminino , Humanos , GravidezRESUMO
Fetal growth restriction results from a failure to achieve a higher growth potential and has been associated with many maternal conditions, such as chronic diseases (infections, hypertension, and some cases of diabetes and obesity), exposures (tobacco smoke, drugs), and malnutrition. This early adversity induces a series of adaptive physiological responses aimed at improving survival, but imposing increased risk for developing chronic nontransmittable diseases (obesity, type II diabetes, cardiovascular disease) in the long term. Recently, mounting evidence has shown that fetal growth impairment is related to altered feeding behavior and preferences through the life course. When living in countries undergoing nutritional transition, in which individuals experience the coexistence of underweight and overweight problems (the "double burden of malnutrition"), fetal growth-restricted children can be simultaneously growth restricted and overweight-a double burden of malnutrition at the individual level. Considering food preferences as an important aspect of nutrition security, we will summarize the putative neurobiological mechanisms at the core of the relationship between fetal growth and nutrition security over the life course and the evidence linking early life adversity to later food preferences.
Assuntos
Ciências da Nutrição Infantil , Retardo do Crescimento Fetal/fisiopatologia , Pré-Escolar , Tomada de Decisões , Diabetes Mellitus Tipo 2/complicações , Ingestão de Alimentos , Comportamento Alimentar , Feminino , Preferências Alimentares , Homeostase , Humanos , Lactente , Recém-Nascido , Masculino , Mães , Neurobiologia , Estado Nutricional , Obesidade/complicações , Sobrepeso , Percepção , Fatores de Risco , Estresse PsicológicoRESUMO
Chronic stress increases anxiety and encourages intake of palatable foods as "comfort foods". This effect seems to be mediated by altered function of the hypothalamic-pituitary-adrenal axis. In the current study, litters of Wistar rats were subjected to limited access to nesting material (Early-Life Stress group - ELS) or standard care (Control group) from postnatal day 2 to 9. In adult life, anxiety was assessed using the novelty-suppressed feeding test (NSFT), and acute stress responsivity by measurement of plasma corticosterone and ACTH levels. Preference for palatable foods was monitored by a computerized system (BioDAQ, Research Diets(®)) in rats receiving only regular chow or given the choice of regular and palatable diet for 30 days. ELS-augmented adulthood anxiety in the NSFT (increased latency to eat in a new environment; decreased chow intake upon return to the home cage) and increased corticosterone (but not ACTH) secretion in response to stress. Despite being lighter and consuming less rat chow, ELS animals ate more palatable foods during chronic exposure compared with controls. During preference testing, controls receiving long-term access to palatable diet exhibited reduced preference for the diet relative to controls exposed to regular chow only, whereas ELS rats demonstrated no such reduction in preference after prolonged palatable diet exposure. The increased preference for palatable foods showed by ELS animals may result from a habit of using this type of food to ameliorate anxiety.
Assuntos
Ansiedade/etiologia , Preferências Alimentares/psicologia , Estresse Psicológico/complicações , Gordura Abdominal/anatomia & histologia , Hormônio Adrenocorticotrópico/sangue , Fenômenos Fisiológicos da Nutrição Animal , Animais , Corticosterona/sangue , Dieta , Ingestão de Alimentos/fisiologia , Comportamento Alimentar , Feminino , Sistema Hipotálamo-Hipofisário , Sistema Hipófise-Suprarrenal , Ratos , Ratos Wistar , Restrição FísicaRESUMO
Intrauterine growth restriction is associated with increased risk for adult metabolic syndrome and cardiovascular disease, which seems to be related to altered food preferences in these individuals later in life. In this study, we sought to understand whether intrauterine growth leads to fetal programming of the hedonic responses to sweet. Sixteen 1-day-old preterm infants received 24% sucrose solution or water and the taste reactivity was filmed and analyzed. Spearman correlation demonstrated a positive correlation between fetal growth and the hedonic response to the sweet solution in the first 15 seconds after the offer (r = 0.864, P = 0.001), without correlation when the solution given is water (r = 0.314, P = 0.455). In fact, the more intense the intrauterine growth restriction, the lower the frequency of the hedonic response observed. IUGR is strongly correlated with the hedonic response to a sweet solution in the first day of life in preterm infants. This is the first evidence in humans to demonstrate that the hedonic response to sweet taste is programmed very early during the fetal life by the degree of intrauterine growth. The altered hedonic response at birth and subsequent differential food preference may contribute to the increased risk of obesity and related disorders in adulthood in intrauterine growth-restricted individuals.
RESUMO
Introdução: Estudos indicam que o trauma precoce e o sistema serotoninérgico estão relacionados ao desenvolvimento de ansiedade. Esta relação poderia ser mediada pela enzima óxido nítrico sintase neuronal (nNOS), que tem papel importante no funcionamento dos receptores de serotonina. Objetivo: Investigar, através da mensuração do óxido nítrico (NO) no hipocampo, o possível envolvimento da nNOS no desenvolvimento de ansiedade em um modelo animal de adversidade no início da vida, baseado na qualidade do cuidado materno. Métodos: Ao segundo dia de vida, genitoras Wistar e suas ninhadas foram divididas em dois grupos: intervenção, com redução do material para a confecção do ninho, ou controle. O comportamento materno foi observado do dia 1 ao dia 9 de vida. Na vida adulta, realizaram-se testes comportamentais e determinaram-se os níveis hipocampais de NO, através da mensuração de seus produtos de degradação. Resultados: Observou-se um maior comportamento do tipo ansioso no grupo intervenção, cujas genitoras apresentaram maior contato de baixa qualidade com seus filhotes. Nos machos, o cuidado materno de baixa qualidade correlacionou-se negativamente com o tempo no braço aberto e a frequência de mergulhos (r=-0,4;p=0,03) avaliados no labirinto em cruz elevado. O comportamento materno de lamber os filhotes correlacionou-se com a frequência de mergulhos em ambos os sexos (r=0,5;p<0,001). A quantidade de NO no hipocampo não diferiu entre os grupos. Conclusão: Uma maior atividade da nNOS não parece estar envolvida no comportamento ansioso observado neste modelo animal, no entanto a relação mãe-filhote, alterada por um ambiente neonatal adverso, teve impacto sobre o comportamento ansioso de forma sexo específica.
Background: Studies have shown that an adverse early life environment and the serotonergic system are related to the development of anxiety. This association could be mediated by neuronal nitric oxide synthase (nNOS), an enzyme that plays an important role in serotonin receptor functioning. Aim: To investigate the possible role of nNOS in the development of anxiety by measuring hippocampal nitric oxide (NO) in an animal model of neonatal stress, based on the quality of maternal care. Methods: On the second day of life, Wistar dams and their litters where divided in two groups: intervention, with limited access to nesting material, or control. Maternal behavior was observed from day 1 to 9 of life. In adult life, behavioral tests were performed and hippocampal NO levels were determined by measuring its degradation products. Results: There was more frequent anxiety-like behavior in the intervention group, whose dams showed low quality contact with their pups more often. In males, low quality maternal care was negatively correlated with time spent in open arms and frequency of head dips (r=-0.4; p=0.03) assessed using an elevated plus maze. Licking and grooming score was correlated with frequency of head dips in both sexes (r=0.5;p<0.001). Hippocampal NO levels were not different between groups (p=0.992). Conclusion: A higher nNOS activity does not seem to be involved in anxiety-like behavior observed in this animal model, however the relationship between dam and pup, modified by an adverse early life environment, had a different impact on anxiety behavior between sexes.
Assuntos
Animais , Ratos , Ansiedade , Comportamento Materno , Óxido Nítrico Sintase/biossíntese , Hipocampo , Modelos Animais , Ratos Wistar/crescimento & desenvolvimentoRESUMO
Esse artigo tem como objetivo discutir os novos desafios no campo da saúde da criança e do adolescente como conseqüência do intenso processo de transição demográfica e epidemiológica brasileiro. Os aspectos relacionados à assistência, à pesquisa e ao ensino dos profissionais de saúde e, a presença de um novo perfil de saúde e doença, com seus novos mecanismos de causalidade são objetos de reflexão buscando alternativas para o enfrentamento e a superação das dificuldades advindas dessa situação. Portanto, esse artigo tenta desenvolver uma análise crítica desse novo cenário na perspectiva de oferecer as respostas pertinentes para as novas demandas em saúde das futuras gerações de brasileiros.
The objective of the present study was to discuss the new challenges of children and adolescent health care related the intensive process of demographic and epidemiological transition in Brazil. Aspects related to health care, research, and education of health professionals, as well as the presence of a new profile of health and disease, including its new mechanisms of causality, are analyzed with the purpose of offering alternatives to face and overcome the difficulties arising from this situation. Therefore, we tried to conduct a critical analysis of this new scenario in order to provide relevant solutions to the new health demands of the next Brazilian generations.
Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Saúde do Adolescente , Saúde da Criança , Pessoal de Saúde/educação , Adolescente , Criança , Dinâmica Populacional , Transição EpidemiológicaRESUMO
There is increasing evidence that early life events can influence neurodevelopment and later susceptibility to disease. Chronic variable stress (CVS) has been used as a model of depression. The objective of this study was to evaluate the interaction between early experience and vulnerability to chronic variable stress in adulthood, analyzing emotional, metabolic and neurochemical aspects related to depression. Pups were (1) handled (10 min/day) or (2) left undisturbed from day 1 to 10 after birth. When the animals reached adulthood, the groups were subdivided and the rats were submitted or not to CVS, which consisted of daily exposure to different stressors for 40 days, followed by a period of behavioral tasks, biochemical (plasma corticosterone and insulin sensitivity) and neurochemical (Naâº,Kâº-ATPase activity in hippocampus, amygdala and parietal cortex) measurements. Neonatally-handled rats demonstrated shorter immobility times in the forced swimming test, independently of the stress condition. There was no difference concerning basal corticosterone or insulin sensitivity between the groups. Naâº,Kâº-ATPase activity was decreased in hippocampus and increased in the amygdala of neonatally-handled rats. CVS decreased the enzyme activity in the three structures, mainly in the non-handled group. These findings suggest that early handling increases the ability to cope with chronic variable stress in adulthood, with animals showing less susceptibility to neurochemical features associated with depression, confirming the relevance of the precocious environment to vulnerability to psychiatric conditions in adulthood.
Assuntos
Corticosterona/sangue , ATPase Trocadora de Sódio-Potássio/metabolismo , Estresse Psicológico/complicações , Estresse Psicológico/metabolismo , Adaptação Psicológica , Tonsila do Cerebelo/metabolismo , Animais , Animais Recém-Nascidos , Glicemia/metabolismo , Depressão/psicologia , Meio Ambiente , Manobra Psicológica , Hipocampo/metabolismo , Resposta de Imobilidade Tônica , Insulina/sangue , Resistência à Insulina/fisiologia , Transtornos do Humor , Lobo Parietal/metabolismo , Ratos , NataçãoRESUMO
This study was undertaken to verify if repeated long-term separation from dams would affect the development of parameters related to post-traumatic stress disorder (PTSD) after animals are subjected to inescapable shock when adults. Wistar rats were subjected to repeated maternal separation during post-natal days 1-10. When adults, rats from both sexes were submitted to a PTSD model consisting of exposure to inescapable footshock, followed by situational reminders. We observed long-lasting effects of both interventions. Exposure to shock increased fear conditioning. Anxiety-like behavior was increased and exploratory activity decreased by both treatments, and these effects were more robust in males. Additionally, basal corticosterone in plasma was decreased, paralleling effects observed in PTSD patients. Levels of S100B protein in serum and cerebrospinal fluid (CSF) were measured. Levels in serum correlated with the effects observed in anxiety-like behavior, increasing in males exposed to shock, and presenting no effect in females. S100B in CSF was increased in females submitted to maternal separation during the neonatal period. These results suggest that, in rats, an early stress experience such as maternal separation may aggravate some effects of exposure to a stressor during adult age, and that this effect is sex-specific. Additionally, data suggest that the increased S100B levels, observed in serum, have an extracerebral origin, possibly mediated by an increase in the noradrenergic tonus. Increased S100B in brain could be related to its neurotrophic actions.
Assuntos
Comportamento Animal/fisiologia , Privação Materna , Fatores de Crescimento Neural/metabolismo , Proteínas S100/metabolismo , Caracteres Sexuais , Transtornos de Estresse Pós-Traumáticos/metabolismo , Análise de Variância , Animais , Animais Recém-Nascidos , Condicionamento Psicológico/fisiologia , Corticosterona/sangue , Modelos Animais de Doenças , Eletrochoque/efeitos adversos , Comportamento Exploratório/fisiologia , Medo/fisiologia , Feminino , Masculino , Gravidez , Ratos , Ratos Wistar , Subunidade beta da Proteína Ligante de Cálcio S100RESUMO
We have previously demonstrated that neonatal handling increases sweet food ingestion. In the present study, we examined whether food intake, using different kinds of food, is altered in neonatally handled animals, with or without inducing satiety using a sucrose solution. Abdominal fat, glycemia and hormones linked to appetite including leptin, ghrelin and insulin were also measured. We tested palatable food consumption in the homecage to verify whether environmental cues could influence ingestion. Nests of Wistar rats were either (1) non-handled or (2) handled (10 min/day). Handling was performed on days 1-10 after birth. When adults, rats were habituated to sweet food (Froot Loops, Kellogg's) and to palatable fiber pellets (Fiber One), Nestlé). Sweet food consumption was increased in the neonatally handled group, when tested in the homecage, and also in the satiety experiment. These rats displayed a satiety curve when compared to the control group, which ate less but constantly. Handled rats exposed to a sucrose solution decreased sweet food ingestion, which did not occur in the control group. When exposed to a food with complex carbohydrates, these differences disappeared. There were no differences in body weight, abdominal fat or in glycemia, as well as no differences in plasma levels of insulin or leptin. However, ghrelin was decreased in neonatally handled rats. Neonatally handled rats demonstrated an increased consumption of sweet food, satiety responses to sucrose, as well as decreased levels of plasma ghrelin. It is possible that signaling mechanisms related to satiety, both peripherally and/or centrally may contribute to these behavioral findings.