Introdução: O modelo teórico, no qual perfis extremos de desigualdade coexistem num cenário complexo promovendo desfechos de saúde similares, denominado “similaridades nas desigualdades”, surgiu de evidências em humanos. O objetivo deste trabalho foi propor um modelo animal para refletir o fenômeno "similaridades nas desigualdades". Métodos: As ratas prenhes foram randomizadas pelo peso corporal, mantidas individualmente e no dia 10 de gestação foram divididas em três grupos: Controle (Cont), que recebeu ração padrão à vontade; Restrição Alimentar 50% (R50%), que recebeu 50% do consumo do grupo controle e Dieta Rica em Gordura (RG), que recebeu uma dieta rica em gordura à vontade. Essas dietas foram oferecidas a partir do dia 10 de gestação até o dia 21 de lactação. Em até 24 horas após o nascimento, todos os filhotes foram adotados por outras mães, formando os seguintes grupos: Cont_Cont, R50%_Cont, R50%_R50%, Cont_R50%, RG_Cont, RG_RG, Cont_RG. Peso corporal e consumo alimentar das genitoras, peso ao nascer, peso ao longo da vida e exercício físico voluntário foram comparados entre grupos por Equação de Estimação Generalizada (GEE), usando diferentes modelos estatísticos. ANOVA de duas vias foi usada para avaliar os desfechos de gordura abdominal e medidas bioquímicas. Resultados: O peso corporal das genitoras Cont e RG foi maior, comparado ao peso das genitoras R50%. Além de alguns efeitos isolados da exposição às dietas R50% ou RG durante momentos específicos perinatais (gestação e/ou lactação), o efeito das "similaridades nas desigualdades" foi observado no peso ao nascer (ambos filhotes R50% e RG foram mais leves do que os Cont) e na atividade física (os grupos extremos R50%_Cont e RG_Cont foram igualmente diferentes do grupo de referência Cont_Cont, sendo machos menos ativos e fêmeas mais ativas). O acompanhamento do peso corporal ao longo da vida mostrou que os machos pesaram mais que as fêmeas. Nenhum dos três modelos estatísticos evidenciou diferenças entre grupos no total de gordura abdominal. Conclusão: Este estudo contribui com a idéia de que as desigualdades em saúde estão relacionadas a resultados similares em saúde para ambos os extremos populacionais, e propõe um modelo animal para explorar ainda mais este efeito. / Introduction: We have previously proposed a theoretical model in which extreme unequal social backgrounds coexist in a complex scenario promoting similar health outcomes, named “Similarities in the inequalities”, and had evidence of this effect in humans. Our objective was to propose an animal model to reflect the “Similarities in the inequalities” phenomenon. Methods: Rats were time-mated and randomly allocated to: Control (Adlib), receiving an ad libitum diet of standard laboratory chow, 50% food restricted (FR), receiving 50% of the ad libitum-fed dam’s intake and high fat diet (HF), receiving a diet containing 45.0% fat. These diets were provided from day 10 of pregnancy throughout the 21-day of lactation. Within 24 hours after birth, all pups were cross-fostered to other dams, forming the following groups: Adlib_Adlib, FR_Adlib, FR_FR, Adlib_FR, HF_Adlib, HF_HF, Adlib_HF. Dam’s body weight and show consumption, pup’s birth weight, growth and physical activity in running wheels, was compared between groups through GEE, using different statistical models. Twoway ANOVA was used to evaluate abdominal fat and biochemical outcomes. Results: Body weight of Adlib and HF dams was higher compared to FR dams. Apart from some isolated effects of the exposure to the FR or HF diets during specific perinatal times (gestation and/or lactation), the “Similarities in the inequalities” effect was seen in birth weight (both FR and HF pups were smaller than Adlib pups) and physical activity (the extreme groups FR_Adlib and HF_Adlib were similarly different from the reference group Adlib_Adlib, being less active in males and more active in females). Body weight monitoring throughout life showed that males were heavier than females. None of the three statistical models showed differences between groups in total abdominal fat. Conclusion: Our study contributes to the idea that health inequalities are related to similar health outcomes for both populational extremes, and proposes an animal model to further explore this effect.

A atividade física é um conhecido fator de proteção, com benefícios tanto para os aspectos metabólicos quanto os psicológicos da saúde. Nosso objetivo foi verificar fatores precoces e tardios determinantes de sedentarismo em adultos jovens. Um total de 2063 indivíduos de uma coorte de nascimentos em Ribeirão Preto, Brasil, foram estudados com a idade de 23/25 anos. Foi realizada Regressão de Poisson utilizando-se três modelos: (1) modelo precoce considerando o peso ao nascer, idade gestacional, escolaridade materna e tabagismo; (2) modelo tardio considerando o sexo do indivíduo, escolaridade e tabagismo; (3) Modelo Combinada (início + tardio). A atividade física foi avaliada através do Questionário Internacional de Atividade Física (IPAQ), estratificando os indivíduos em ativos ou sedentários. A taxa geral de comportamento sedentário na amostra foi de 49,6%. No modelo inicial, baixo peso ao nascer (RR = 1.207, 95% CI 1.023-1.423) e menores níveis de escolaridade materna (RR = 1,213, 95% CI 1.028-1.430) foram fatores de risco para a atividade sedentária. O sexo feminino (RR=1,385, 95% CI 1.285-1.516) e baixa escolaridade (RR=1.138,95% CI 1.021-1.269) foram associados com o comportamento sedentário no modelo final. No modelo combinado, apenas o sexo feminino permaneceu significativo. Além disso, uma interação entre peso ao nascer e escolaridade do indivíduo foi encontrado, em que o comportamento sedentário foi estatisticamente mais freqüente em indivíduos nascidos com baixo peso ao nascer apenas se eles tivessem níveis mais altos de ensino. Este estudo mostra que as variáveis de desenvolvimento precoce, tais como peso ao nascimento e inserção social na vida adulta interage para determinar a disposição de um indivíduo para a prática de atividades físicas. O estudo é um exemplo do modelo teórico "Semelhanças entre as desigualdades", no qual extremos de status social demonstrar um resultado semelhante (neste caso o comportamento sedentário). / Physical activity is a known protective factor, with benefits for both the metabolic and psychological aspects of health. Our objective was to verify early and late determinants of physical activity in young adults. A total of 2063 individuals from a birth cohort in Ribeirão Preto, Brazil, were studied at the age of 23/25 years. Poisson regression was performed using three models: (1) Early model considering birth weight, gestational age, maternal schooling and smoking; (2) Late model considering individual’s gender, schooling and smoking; (3) Combined (early + late) model. Physical activity was evaluated using the International Physical Activity Questionnaire (IPAQ), stratifying the individuals into active or sedentary. The general rate of sedentary behavior in the sample was 49.6%. In the early model, low birth weight (RR=1.207, 95%CI 1.023-1.423) and lower levels of maternal education (RR=1.213, 95%CI 1.028-1.430) were risk factors for sedentary activity. Female gender (RR=1.385, 95%CI 1.285-1.516) and poor schooling (RR=1.138,95%CI 1.021- 1.269) were associated with sedentary behavior in the late model. In the combined model, only female gender remained significant. In addition, an interaction between birth weight and individual’s schooling was found, in which sedentary behavior was statistically more prevalent in individuals born with low birth weight only if they had higher educational levels. This study shows that variables of early development such as birth weight and social insertion in later life interact to determine an individual’s disposition to practice physical activities. The study is an example of the theoretical model “Similarities in the inequalities”, in which extremes of social status demonstrate a similar outcome (in this case sedentary behavior).

Introdução: O modelo teórico, no qual perfis extremos de desigualdade coexistem num cenário complexo promovendo desfechos de saúde similares, denominado “similaridades nas desigualdades”, surgiu de evidências em humanos. O objetivo deste trabalho foi propor um modelo animal para refletir o fenômeno "similaridades nas desigualdades". Métodos: As ratas prenhes foram randomizadas pelo peso corporal, mantidas individualmente e no dia 10 de gestação foram divididas em três grupos: Controle (Cont), que recebeu ração padrão à vontade; Restrição Alimentar 50% (R50%), que recebeu 50% do consumo do grupo controle e Dieta Rica em Gordura (RG), que recebeu uma dieta rica em gordura à vontade. Essas dietas foram oferecidas a partir do dia 10 de gestação até o dia 21 de lactação. Em até 24 horas após o nascimento, todos os filhotes foram adotados por outras mães, formando os seguintes grupos: Cont_Cont, R50%_Cont, R50%_R50%, Cont_R50%, RG_Cont, RG_RG, Cont_RG. Peso corporal e consumo alimentar das genitoras, peso ao nascer, peso ao longo da vida e exercício físico voluntário foram comparados entre grupos por Equação de Estimação Generalizada (GEE), usando diferentes modelos estatísticos. ANOVA de duas vias foi usada para avaliar os desfechos de gordura abdominal e medidas bioquímicas. Resultados: O peso corporal das genitoras Cont e RG foi maior, comparado ao peso das genitoras R50%. Além de alguns efeitos isolados da exposição às dietas R50% ou RG durante momentos específicos perinatais (gestação e/ou lactação), o efeito das "similaridades nas desigualdades" foi observado no peso ao nascer (ambos filhotes R50% e RG foram mais leves do que os Cont) e na atividade física (os grupos extremos R50%_Cont e RG_Cont foram igualmente diferentes do grupo de referência Cont_Cont, sendo machos menos ativos e fêmeas mais ativas). O acompanhamento do peso corporal ao longo da vida mostrou que os machos pesaram mais que as fêmeas. Nenhum dos três modelos estatísticos evidenciou diferenças entre grupos no total de gordura abdominal. Conclusão: Este estudo contribui com a idéia de que as desigualdades em saúde estão relacionadas a resultados similares em saúde para ambos os extremos populacionais, e propõe um modelo animal para explorar ainda mais este efeito. / Introduction: We have previously proposed a theoretical model in which extreme unequal social backgrounds coexist in a complex scenario promoting similar health outcomes, named “Similarities in the inequalities”, and had evidence of this effect in humans. Our objective was to propose an animal model to reflect the “Similarities in the inequalities” phenomenon. Methods: Rats were time-mated and randomly allocated to: Control (Adlib), receiving an ad libitum diet of standard laboratory chow, 50% food restricted (FR), receiving 50% of the ad libitum-fed dam’s intake and high fat diet (HF), receiving a diet containing 45.0% fat. These diets were provided from day 10 of pregnancy throughout the 21-day of lactation. Within 24 hours after birth, all pups were cross-fostered to other dams, forming the following groups: Adlib_Adlib, FR_Adlib, FR_FR, Adlib_FR, HF_Adlib, HF_HF, Adlib_HF. Dam’s body weight and show consumption, pup’s birth weight, growth and physical activity in running wheels, was compared between groups through GEE, using different statistical models. Twoway ANOVA was used to evaluate abdominal fat and biochemical outcomes. Results: Body weight of Adlib and HF dams was higher compared to FR dams. Apart from some isolated effects of the exposure to the FR or HF diets during specific perinatal times (gestation and/or lactation), the “Similarities in the inequalities” effect was seen in birth weight (both FR and HF pups were smaller than Adlib pups) and physical activity (the extreme groups FR_Adlib and HF_Adlib were similarly different from the reference group Adlib_Adlib, being less active in males and more active in females). Body weight monitoring throughout life showed that males were heavier than females. None of the three statistical models showed differences between groups in total abdominal fat. Conclusion: Our study contributes to the idea that health inequalities are related to similar health outcomes for both populational extremes, and proposes an animal model to further explore this effect.

Introdução: O modelo teórico, no qual perfis extremos de desigualdade coexistem num cenário complexo promovendo desfechos de saúde similares, denominado “similaridades nas desigualdades”, surgiu de evidências em humanos. O objetivo deste trabalho foi propor um modelo animal para refletir o fenômeno "similaridades nas desigualdades". Métodos: As ratas prenhes foram randomizadas pelo peso corporal, mantidas individualmente e no dia 10 de gestação foram divididas em três grupos: Controle (Cont), que recebeu ração padrão à vontade; Restrição Alimentar 50% (R50%), que recebeu 50% do consumo do grupo controle e Dieta Rica em Gordura (RG), que recebeu uma dieta rica em gordura à vontade. Essas dietas foram oferecidas a partir do dia 10 de gestação até o dia 21 de lactação. Em até 24 horas após o nascimento, todos os filhotes foram adotados por outras mães, formando os seguintes grupos: Cont_Cont, R50%_Cont, R50%_R50%, Cont_R50%, RG_Cont, RG_RG, Cont_RG. Peso corporal e consumo alimentar das genitoras, peso ao nascer, peso ao longo da vida e exercício físico voluntário foram comparados entre grupos por Equação de Estimação Generalizada (GEE), usando diferentes modelos estatísticos. ANOVA de duas vias foi usada para avaliar os desfechos de gordura abdominal e medidas bioquímicas. Resultados: O peso corporal das genitoras Cont e RG foi maior, comparado ao peso das genitoras R50%. Além de alguns efeitos isolados da exposição às dietas R50% ou RG durante momentos específicos perinatais (gestação e/ou lactação), o efeito das "similaridades nas desigualdades" foi observado no peso ao nascer (ambos filhotes R50% e RG foram mais leves do que os Cont) e na atividade física (os grupos extremos R50%_Cont e RG_Cont foram igualmente diferentes do grupo de referência Cont_Cont, sendo machos menos ativos e fêmeas mais ativas). O acompanhamento do peso corporal ao longo da vida mostrou que os machos pesaram mais que as fêmeas. Nenhum dos três modelos estatísticos evidenciou diferenças entre grupos no total de gordura abdominal. Conclusão: Este estudo contribui com a idéia de que as desigualdades em saúde estão relacionadas a resultados similares em saúde para ambos os extremos populacionais, e propõe um modelo animal para explorar ainda mais este efeito. / Introduction: We have previously proposed a theoretical model in which extreme unequal social backgrounds coexist in a complex scenario promoting similar health outcomes, named “Similarities in the inequalities”, and had evidence of this effect in humans. Our objective was to propose an animal model to reflect the “Similarities in the inequalities” phenomenon. Methods: Rats were time-mated and randomly allocated to: Control (Adlib), receiving an ad libitum diet of standard laboratory chow, 50% food restricted (FR), receiving 50% of the ad libitum-fed dam’s intake and high fat diet (HF), receiving a diet containing 45.0% fat. These diets were provided from day 10 of pregnancy throughout the 21-day of lactation. Within 24 hours after birth, all pups were cross-fostered to other dams, forming the following groups: Adlib_Adlib, FR_Adlib, FR_FR, Adlib_FR, HF_Adlib, HF_HF, Adlib_HF. Dam’s body weight and show consumption, pup’s birth weight, growth and physical activity in running wheels, was compared between groups through GEE, using different statistical models. Twoway ANOVA was used to evaluate abdominal fat and biochemical outcomes. Results: Body weight of Adlib and HF dams was higher compared to FR dams. Apart from some isolated effects of the exposure to the FR or HF diets during specific perinatal times (gestation and/or lactation), the “Similarities in the inequalities” effect was seen in birth weight (both FR and HF pups were smaller than Adlib pups) and physical activity (the extreme groups FR_Adlib and HF_Adlib were similarly different from the reference group Adlib_Adlib, being less active in males and more active in females). Body weight monitoring throughout life showed that males were heavier than females. None of the three statistical models showed differences between groups in total abdominal fat. Conclusion: Our study contributes to the idea that health inequalities are related to similar health outcomes for both populational extremes, and proposes an animal model to further explore this effect.

A atividade física é um conhecido fator de proteção, com benefícios tanto para os aspectos metabólicos quanto os psicológicos da saúde. Nosso objetivo foi verificar fatores precoces e tardios determinantes de sedentarismo em adultos jovens. Um total de 2063 indivíduos de uma coorte de nascimentos em Ribeirão Preto, Brasil, foram estudados com a idade de 23/25 anos. Foi realizada Regressão de Poisson utilizando-se três modelos: (1) modelo precoce considerando o peso ao nascer, idade gestacional, escolaridade materna e tabagismo; (2) modelo tardio considerando o sexo do indivíduo, escolaridade e tabagismo; (3) Modelo Combinada (início + tardio). A atividade física foi avaliada através do Questionário Internacional de Atividade Física (IPAQ), estratificando os indivíduos em ativos ou sedentários. A taxa geral de comportamento sedentário na amostra foi de 49,6%. No modelo inicial, baixo peso ao nascer (RR = 1.207, 95% CI 1.023-1.423) e menores níveis de escolaridade materna (RR = 1,213, 95% CI 1.028-1.430) foram fatores de risco para a atividade sedentária. O sexo feminino (RR=1,385, 95% CI 1.285-1.516) e baixa escolaridade (RR=1.138,95% CI 1.021-1.269) foram associados com o comportamento sedentário no modelo final. No modelo combinado, apenas o sexo feminino permaneceu significativo. Além disso, uma interação entre peso ao nascer e escolaridade do indivíduo foi encontrado, em que o comportamento sedentário foi estatisticamente mais freqüente em indivíduos nascidos com baixo peso ao nascer apenas se eles tivessem níveis mais altos de ensino. Este estudo mostra que as variáveis de desenvolvimento precoce, tais como peso ao nascimento e inserção social na vida adulta interage para determinar a disposição de um indivíduo para a prática de atividades físicas. O estudo é um exemplo do modelo teórico "Semelhanças entre as desigualdades", no qual extremos de status social demonstrar um resultado semelhante (neste caso o comportamento sedentário). / Physical activity is a known protective factor, with benefits for both the metabolic and psychological aspects of health. Our objective was to verify early and late determinants of physical activity in young adults. A total of 2063 individuals from a birth cohort in Ribeirão Preto, Brazil, were studied at the age of 23/25 years. Poisson regression was performed using three models: (1) Early model considering birth weight, gestational age, maternal schooling and smoking; (2) Late model considering individual’s gender, schooling and smoking; (3) Combined (early + late) model. Physical activity was evaluated using the International Physical Activity Questionnaire (IPAQ), stratifying the individuals into active or sedentary. The general rate of sedentary behavior in the sample was 49.6%. In the early model, low birth weight (RR=1.207, 95%CI 1.023-1.423) and lower levels of maternal education (RR=1.213, 95%CI 1.028-1.430) were risk factors for sedentary activity. Female gender (RR=1.385, 95%CI 1.285-1.516) and poor schooling (RR=1.138,95%CI 1.021- 1.269) were associated with sedentary behavior in the late model. In the combined model, only female gender remained significant. In addition, an interaction between birth weight and individual’s schooling was found, in which sedentary behavior was statistically more prevalent in individuals born with low birth weight only if they had higher educational levels. This study shows that variables of early development such as birth weight and social insertion in later life interact to determine an individual’s disposition to practice physical activities. The study is an example of the theoretical model “Similarities in the inequalities”, in which extremes of social status demonstrate a similar outcome (in this case sedentary behavior).

La nutrition au cours de la période postnatale précoce programme l’activité de l’axe somatotrope à l’âge adulte (GH/IGF-1). Une altération de la nutrition chez les souriceaux au cours de la lactation altère la croissance staturo-pondérale de façon permanente et augmente leurs susceptibilités à développer des pathologies cardio-métaboliques à l’âge adulte. La restriction au cours de la lactation induit une diminution des taux plasmatiques en IGF-1 et en leptine. Ceci est associé à une diminution transitoire de l’innervation de l’éminence médiane par les neurones GHRH, ce qui induit une hypoplasie hypophysaire permanente en cellules somatotropes. Durant ma thèse, j’ai étudié l’impact de la nutrition périnatale sur la mise en place de l’axe somatotrope, notamment les mécanismes impliqués dans la régulation du développement des neurones GHRH. Les cultures d’explants de noyaux arqués issus de souriceaux normalement nourris indiquent que l’IGF-1 stimule de façon préférentielle la croissance axonale des neurones GHRH par l'intermédiaire des voies PI3K/AKT et MAPK. La leptine présenterait quant à elle un effet plus global sur les neurones du noyau arqué, stimulant la croissance axonale des neurones GHRH et des neurones orexigène à NPY/AgRP. Les neurones GHRH issus de souris restreintes sont quant à eux résistants à la stimulation de la croissance axonale par l’IGF-1 ou la leptine. Concernant l’IGF-I, cette résistance est associée à une altération des capacités de phosphorylation de la voie PI3K/AKT, tandis que celles de l’IGF-1R et de la voie MAPK ne sont pas altérées. / Nutrition during lactation programs the activity of the somatotropic axis (GH/IGF-1). Alteration of nutrition during the early postnatal period in mice induces increased susceptibility to develop cardiovascular and metabolic pathologies later in life. Nutritional restriction during lactation permanently alters growth of mice. Ten days old restricted pups present decreased plasmatic level of IGF-1 and Leptin. They also present a transient alteration of median eminence innervation by GHRH neurons, which induce a permanent somatotroph cells (GH) hypoplasia in pituitary. The aim of my thesis was to study the impact of nutrition during the perinatal period on the programming of the somatotropic axis, notably the cellular and molecular mechanisms involved in the regulation of GHRH neuronal development. In vitro cultures of arcuate nucleus explants of hypothalamus from normally fed pups indicate that IGF-1 preferentially stimulates axonal growth of GHRH neurons by its signaling pathways PI3K/AKT and MAPK. Leptin present a more global effect and is able to stimulate axonal growth of arcuate nucleus neurons, including GHRH and AgRP neurons. GHRH neurons from restricted pups are resistant to the stimulation of axonal growth by IGF-1 or leptin. Regarding IGF-1, this resistance is associated with an alteration of phosphorylation capacities of the PI3K/AKT pathway, whereas those from IGF-1R and MAPK are not altered.

16 Abstract The rising prevalence in noncommunicable diseases worldwide calls for the effort to determine their underlying causes. Common metabolic disorders in particular overwhelm the healthcare systems and are a one of the leading causes of poor quality of life of patients. Metabolic syndrome is represented by concurrence of several conditions - dyslipidaemia, obesity, hypertension or impaired glucose tolerance - altered metabolic phenotypes related to genetic and environmental factors. Recent studies suggest that early-life exposure to certain environmental stimuli is particularly capable of changing the mammalian phenotypes. Nutrition, as one of the major factors influencing health, is naturally a focus of research, which studies the link between parental diets and phenotypic alterations in offspring. The developmental origins of health and disease were historically more focused on maternal undernutrition, it is, however, more important to focus on surplus of macronutrients considering the westernization of modern diets. We propose the relevancy of not only the amount of macronutrients in maternal diet, but also their sources, as they may increase disease risk in offspring. Here we report, that sucrose as an alternative carbohydrate in maternal diet, has a marked impact on metabolism of the offspring...

Não disponível / Background: Visceral adiposity is a risk factor for cardiometabolic diseases and dual-energy x-ray absorptiometry (DXA) represents precise method for measuring visceral adipose tissue (VAT), muscle and bone compartments. The musculoskeletal system deteriorates with aging and may result in osteosarcopenia. Since known risk factors do not fully explain the occurrence of osteosarcopenia, the search for new causal factors, as birth weight (BW) is promising. Objectives: To evaluate whether BW was associated with DXA-determined body composition, bone densitometry and cardiometabolic risk markers in young women from the NutriHS. Paper 1 objective: to propose reference values for DXA-determined VAT, and to test their ability to identify the cardiometabolic risk profile. Paper 2: to examine whether BW was associated with muscle and bone DXA-determined parameters. Paper 3: to investigate whether parameters of muscle and bone compartments were associated and possible predictive factors of these compartments throughout life. Methods: NutriHS is a cohort study conducted in undergraduates and Nutrition graduates and here cross-sectional analyses were performed in 201 healthy women (20-45 years). They answered questionnaires and had anthropometry, muscle strength and performance, DXA-determined body composition and bone densitometry obtained. A random sample of 148 participants had also laboratory tests collected. Multiple regression models, using the directed acyclic graphs-recommended adjustments, were employed. Results: Median age was 23 years and mean BMI was 22.9±2.9 kg/m2. Paper 1: Mean VAT mass and volume were 221.0±306.1 g and 231.8±323.8 cm3, respectively. The third tertiles of VAT were significantly associated with increased frequencies of abnormal anthropometry, HOMA-IR and TyG indexes. Paper 2: Mean BW was 3,199±424 g; BW in quartiles was significantly associated with several muscle and bone parameters. Paper 3: Direct, strong and independent associations between bone and muscle variables were detected. Discussion: Cutoffs for DXA-derived VAT mass (221.0 g) and volume (231.8 cm3) are being suggested for Brazilian young women; these seem able to disclose a mild visceral fat accumulation, prior the deterioration of glucose and lipid metabolism. The role of BW as an early marker for muscle and bone states in young adulthood was shown. In addition, a musculoskeletal profile for a healthy stratus of the Brazilian women was firstly described. Our findings indicated a muscle-bone crosstalk even in young adults and suggested predictive factors (such as BW, physical activity, smoking) of muscle and bone compartments.

Puerto Rico has the highest prevalence of type 2 diabetes, low birth-weight, and the second highest prevalence of preterm-birth in all the U.S. and its non-incorporated territories. These conditions are related. Birth-weight at both ends of the spectrum and preterm-birth are associated with an increased risk for developing type 2 diabetes and immune-inflammatory dysregulations. Maternal psychosocial stressors during pregnancy have also been recognized as potential risk factors for type 2 diabetes, and have been consistently associated with preterm-birth and low birth-weight across populations. Current evidence points toward epigenetic fetal metabolic-programming as the mechanism that underlies the increased risk for the previously mentioned morbidities. However, the particular psychosocial stressors that may contribute to the high prevalence of low birth-weight and preterm-birth in the population of Puerto Rico have not been well studied. The present study assesses the relationships between particular psychosocial stressors, socioeconomic status, food insecurity, and birth outcomes. The results of this study show that low-risk pregnancy women were more likely to have babies with a higher ponderal index if they were exposed to stressors during gestation months 5, 6, and 7, or if exposed to "relationship stress" at any time during pregnancy. Women exposed to "financial difficulties" at any time during pregnancy were more likely to deliver babies at an earlier gestational age. Differences in birth outcomes between the exposed and non-exposed women were independent of maternal anthropometric measurements, maternal age at birth, number of previous births, and sex of the baby. Significant differences in birth outcomes were found between categories of father's self-identified and identified by others ethnicity, but sample size within categories was small. Although mothers with children at home had higher levels of food insecurity, and the level of food insecurity was correlated with higher levels of stress, no birth outcome measure was associated with food insecurity. Some results are atypical in comparison with other populations, and therefore these findings may contribute to the understanding of population differences in the relationship between maternal stress during pregnancy and birth outcomes. The relatively small sample size and strict exclusion criteria of this study may limit the generalizability of the findings. Epidemiological similarities between Puerto Rico and other populations, and the possibility of a higher ponderal index increasing the risk for type 2 diabetes in the population of Puerto Rico need to be examined in future research.

Background: Maternal stress during utero has been shown to have negative health consequences on the offspring, including low birth weight and increased risk of adult disease. Variation in breastmilk may act as an environmental cue of maternal stress and continue to program the infant during early life. This research aimed to explore the role of breastmilk on developmental programming of the infant. Specifically, to examine how breastmilk may act as a medium for the exposure of stress between the mother and the offspring, and see if variation in insulin like growth factor-1 (IGF-1) a potential mechanism for the relationship. Methods: Survey-interviews, anthropometrics of the mother and offspring (height and weight), and breastmilk samples were collected for 31 breastfeeding mother-offspring pairs in the Tampa Bay area. Breastmilk was analyzed for IGF-1 and fat content. Maternal stress was measured through the PSS-10 and two self-reported ten-point stress scales. Offspring length for age and weight for age Z-scores were calculated using LMS equation. Results: PPS-10 score was negatively correlated with child length for age and weight for age Z-scores. Child length for age and weight for age Z-scores were also negatively correlated with the breastmilk fat variables (creamatocrit percent, fat g/dL, and kcal/dL). No relationships were found between breastmilk IGF-1 and offspring length for age, weight for age, or maternal stress. Conclusions: Results indicate that maternal stress may negatively impact offspring growth. However, more research is necessary to better understand if or how breastmilk fat may act as a mechanism to mediate offspring growth due to maternal stress. This sample had low levels and prevalence of detectable IGF-1, which likely contributed to the lack of statistical relationships. Further research using lower dilutions and larger samples sizes is necessary to better explore the potential role of breastmilk IGF-1 on offspring growth and/or its relationship to maternal stress.