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BACKGROUND/OBJECTIVE: To compare the association between anthropometric indicators of global and central obesity as predictors of total body fat (TBF) and cardiometabolic risk factors in children. SUBJECTS/METHODS: A total of 1044 children were evaluated at 4 years (n=320), 7 years (n=1044) and 10 years (n=483). The following anthropometric indices were determined: body mass index (BMI) for age (BAZ, WHO), waist circumference (WC), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR). To estimate TBF we used validated predictive equations. We measured blood sample concentrations of glucose, insulin, triglycerides, total cholesterol, Low-density lipoprotein (LDL) and High-density lipoprotein (HDL), adiponectin, C-reactive protein (CRP) and Insulin-like growth factor-1 (IGF-1). RESULTS: Adiposity and cardiometabolic markers, particularly those related to glucose metabolism increased from 4 years to 10 years. BAZ and WC were highly correlated to body fat at all ages (all r>0.8) but at 10 years WC was more strongly correlated than BAZ (r=0.94 WC vs r=0.88 BAZ, P<0.05); conversely, WHtR was significantly associated with body fat from 7 years (r=0.85) and 10 years (r=0.88). WHR was unrelated all over the period studied at all ages. Anthropometrical adiposity indicators became associated to cardiometabolic markers only from 7 years on with associations being slightly higher at 10 years, particularly for adiponectin and lipid markers. At all ages, BAZ, WC and WHtR performed similarly as cardiometabolic markers (P<0.05) while WHR was a slightly weaker marker. CONCLUSIONS: Relationship between anthropometrical indicators of adiposity and cardiometabolic markers becomes stronger from 7 years onwards; BAZ, WC and WHtR perform similarly as markers of cardiometabolic risk at least until 10 years of age.
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Tecido Adiposo , Adiposidade , Antropometria/métodos , Síndrome Metabólica/etiologia , Obesidade Infantil/etiologia , Adiponectina/sangue , Fatores Etários , Glicemia/análise , Índice de Massa Corporal , Proteína C-Reativa , Criança , Pré-Escolar , Chile , Colesterol/sangue , Feminino , Humanos , Insulina/sangue , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Masculino , Fatores de Risco , Triglicerídeos/sangue , Circunferência da Cintura , Razão Cintura-Estatura , Relação Cintura-QuadrilRESUMO
BACKGROUND/OBJECTIVE: In Chile, approximately one in three children under 6 years of age reported overweight/obese, while one in four children in elementary school suffer from obesity. There is a paucity of population-based information on the influence of childhood eating behavior on anthropometric measures related to obesity. To assess the association between eating behavior scores and Body Mass Index (BMI) z-scores in 7-10-year-old Chilean children. SUBJECTS/METHODS: We conducted a cross-sectional study in 1058 children aged 7-10 (51% girls) from the 'Growth and Obesity Chilean Cohort Study' (GOCS). Direct measures of weight and height were used to compute BMI z-scores according to World Health Organization (WHO) curves. Children were classified as normal weight (-1<1 s.d.), overweight (1<2 s.d.) and obese (⩾2 s.d.). Eating behavior scores were measured through the Child Eating Behavior Questionnaire (CEBQ), previously adapted and validated for Chilean children. Multiple linear regressions were carried out using BMI z-score as the outcome and eating behavior scores as explanatory variables. All models were adjusted by age and gender. RESULTS: BMI z-scores were positively associated with pro-intake scores in the subscales 'enjoyment of food', 'emotional overeating' and 'food responsiveness' (P<0.0001). Contrary to other studies, 'desire for drinks' scores were also associated with BMI z-scores (P<0.0001). In contrast, food-avoidant 'satiety responsiveness', 'slowness in eating' and 'food-fussiness' scores were negatively associated with BMI z-scores (P<0.0001). CONCLUSION: We found a significant relationship between eating behavior scores and BMI z-scores in Chilean children, showing that BMI in 7-10-year-old Chilean children is positively associated with pro-intake eating behavior scores and negatively associated with anti-intake eating behavior scores. The identification of specific eating behaviors patterns related to obesity will provide important information for the implementation of prevention programs for this disease.
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Índice de Massa Corporal , Comportamento Infantil/psicologia , Ingestão de Alimentos/psicologia , Comportamento Alimentar/psicologia , Obesidade Infantil/psicologia , Antropometria , Criança , Chile , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , MasculinoRESUMO
In humans, obesity before and during pregnancy is associated with both fetal macrosomia and growth restriction, and long-term cardiovascular risk in the offspring. We aimed to determine whether overweighted pregnant guinea pig sows results in an increased fetal weight at term and the effects on the vascular reactivity in fetal systemic and umbilical arteries. Pregnant guinea pigs were classified as control (n=4) or high weight (HWS, n=5) according to their pre-mating weight, and their fetuses extracted at 0.9 gestation (~60 days). Segments of fetal femoral and umbilical arteries were mounted in a wire myograph, where the contractile response to KCl (5-125 mM), and the relaxation to nitric oxide synthase-dependent agents (insulin, 10-10-10-7 and acetylcholine, 10-10-10-5) and nitric oxide [sodium nitroprusside (SNP), 10-10-10-5] were determined. Fetuses from HWS (HWSF) were grouped according to their body weight as low (85 g) fetal weight, based on the confidence interval (76.5-84.9 g) of the control group. No HWSF were observed in the normal range. Umbilical arteries from HWSF showed a lower response to KCl and insulin compared with controls, but a comparable response with SNP. Conversely, femoral arteries from HWSF showed an increased response to KCl and acetylcholine, along with a decreased sensitivity to SNP. These data show that overweight sows have altered fetal growth along gestation. Further, large and small fetuses from obese guinea pig sows showed altered vascular reactivity at umbilical and systemic vessels, which potentially associates with long-term cardiovascular risk.
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BACKGROUND: Consistent data on the relation between vitamin D, body fat and insulin resistance (IR) in children are lacking. OBJECTIVES: (1) To evaluate the association between serum 25-Hydroxyvitamin D [25(OH)D] and key indicators of: adiposity (total and central), IR, and (2) to estimate serum 25(OH)D cut-offs that best reflect IR and total and central adiposity in children. SUBJECTS/METHODS: Prepubertal children (n=435, ~53% girls; ~age 7 years) from the Growth and Obesity Chilean Cohort Study were evaluated for potential associations between serum 25(OH)D and indicators of: (1) total adiposity (body mass index by age (BAZ), body fat (including three-component model)), central adiposity (waist circumference and trunk fatness); (2) IR (homeostasis model assessment of IR) and insulin sensitive (quantitative insulin sensitivity check index) using standardized multiple regression models with standardized coefficients and receiver operating characteristic curves. RESULTS: Overall, mean serum 25(OH)D was 32.1±9.2 ng ml(-1), while 19.4% of children were obese (BAZ⩾2 s.d.). Serum 25(OH)D was inversely associated with indicators of total and central adiposity and with IR indicators. Effect sizes were moderate in girls (~0.3 for adiposity and IR indicators), while, weaker values were found in boys. Serum 25(OH)D estimated cut-offs that best predicted total, central adiposity and IR were~30 ng ml(-1). Children with suboptimal serum 25(OH)D (<30 ng ml(-1)) had a higher risk (two to three times) of being obese (high BAZ, body fat percent and/or central adiposity); and three to four times greater risk for IR. CONCLUSIONS: Serum 25(OH)D was inversely associated with adiposity (total and central) and IR indicators in prepubertal Chilean children. The conventional cut-off of vitamin D sufficiency (⩾30 ng ml(-1)) was adequate to assess obesity and IR risk in this age group.
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Obesidade Abdominal/etiologia , Deficiência de Vitamina D/complicações , Vitamina D/análogos & derivados , Adiposidade , Composição Corporal , Índice de Massa Corporal , Criança , Chile/epidemiologia , Feminino , Seguimentos , Humanos , Resistência à Insulina , Estudos Longitudinais , Masculino , Obesidade Abdominal/sangue , Obesidade Abdominal/epidemiologia , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/epidemiologiaRESUMO
INTRODUCTION: Fetal macrosomia and intrauterine growth restriction (IUGR) associate with increased morbidity in the neonate. Placental vascular relaxation is impaired in fetal macrosomia, as well as in IUGR, and this could result from increased oxidative stress present in both conditions. We determined the role of pro- and anti-oxidants on NOS dependent relaxation in placental chorionic arteries from pregnancies with LGA babies from overweight and/or obese mothers (LOOM) and IUGR fetuses from normal BMI women. METHODS: Chorionic arteries were mounted in a wire-myograph, where responses to the NOS-dependent agent CGRP in presence or absence of the antioxidant N-acetyl cysteine (NAC), the pro-oxidant SIN-1, the SOD inhibitor DDC, and the GPx inhibitor MS were determined. Additionally the presence of pro- and antioxidant enzymes (NOX-4, SOD-1, SOD-2 and GPx-1) and eNOS in chorionic and umbilical vessels were addressed by immunohistochemistry. RESULTS: Maximal CGRP-induced relaxation was comparable to controls but presented a reduced potency in chorionic arteries from LOOM placentae, whilst in IUGR vessels both maximal response and potency were reduced. NAC increased maximal relaxation in controls, IUGR and LOOM arteries, whilst SIN-1 completely abolished the CGRP-induced relaxation only in IUGR and LOOM samples, the later effect was paralleled by SOD or GPx inhibition. These responses associated with the presence of NOX-4, SOD-1 and GPx-1 in the endothelium and vascular wall of chorionic and umbilical arteries in the different groups studied. DISCUSSION: These data suggest that NOS dependent relaxation in placental vessels from IUGR and LOOM pregnancies present a higher sensitivity to oxidative stress.
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Artérias/fisiopatologia , Endotélio Vascular/fisiopatologia , Retardo do Crescimento Fetal/fisiopatologia , Macrossomia Fetal/fisiopatologia , Obesidade/fisiopatologia , Adulto , Antioxidantes/metabolismo , Artérias/metabolismo , Estudos de Casos e Controles , Feminino , Glutationa Peroxidase/metabolismo , Humanos , Técnicas In Vitro , NADPH Oxidase 4 , NADPH Oxidases/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo , Placenta/fisiopatologia , Gravidez , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1 , Glutationa Peroxidase GPX1RESUMO
BACKGROUND/OBJECTIVE: The aim of this study was to assess the validity of body fatness estimations based on skinfolds and bioelectrical iImpedance analyses (BIA) measurements compared to a three-component model (3C model) in prepubertal Chilean children, considering potential differences by sex and nutritional status. SUBJECTS/METHODS: Four hundred and twenty four Chilean children (198 females and 226 males) were assessed for body composition. Body fat percentage (BF%) was evaluated by Skinfold equations (Slaughter, Ramirez and Huang) and Bioelectrical impedance (BIA: Tanita BC-418MA) using both the equipment and the Ramirez equation. Measurements based on a 3C model constructed from total body water estimates by isotope dilution and from body volume estimates by air displacement plethysmography were used as gold standard. RESULTS: Coefficient of determination (R2) values were higher in overweight and in the whole group of both gender. All slopes were differed significantly from 1, and most intercepts were significantly different from 0. Skinfold Equations: an underestimation of BF% was found for all equations, being higher with the Slaughter equation. BIA: Tanita underestimated BF% in all groups, whereas Ramirez equation shows an overestimation. CONCLUSIONS: Skinfolds and bio-impedance equations serve well to rank children according to their BF%. However, these methods are not accurate for describing body composition in prepubertal Chilean children.
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Tecido Adiposo , Antropometria/métodos , Composição Corporal/fisiologia , Impedância Elétrica , Dobras Cutâneas , Fatores Etários , Criança , Pré-Escolar , Chile , Feminino , Humanos , Técnicas de Diluição do Indicador , Masculino , Sobrepeso , Pletismografia , PuberdadeRESUMO
BACKGROUND: Early adiposity rebound (AR <5 years) has been consistently associated with increased obesity risk, but its relationship with metabolic markers is less clear; in addition, the biologic mechanisms involved in these associations have not been established. OBJECTIVE: The objective of this study was to assess the association between timing of AR and metabolic status at age 7 years, evaluating the potential role of adiposity, adipose functionality and skeletal maturation in this association. DESIGN: We estimated the age of AR from the body mass index (BMI) trajectories from 0 to 7 years in 910 children from the Growth and Obesity Chilean Cohort Study (GOCS). At 7 years, we measured waist circumference (WC) and blood glucose, insulin, triglycerides and high-density lipoprotein-cholesterol levels and constructed a metabolic risk score. We also measured percent fat mass (adiposity), plasma concentrations of leptin and adiponectin (adipose functionality) and bone age using wrist ultrasound (skeletal maturation). RESULTS: We found that 44% of the children had an AR <5 years. Earlier AR was associated with larger WC (ß: 5.10 (95% confidence interval (CI): 4.29-5.91)), higher glucose (ß: 1.02 (1.00-1.03)), insulin resistance (ß Homeostatic Model Assessment: 1.06 (1.03-1.09)), triglycerides (ß: 10.37 (4.01-6.73)) and adverse metabolic score (ß: 0.30 (0.02-0.37)). Associations decreased significantly if adiposity was added to the models (i.e. ß WC: 0.85 (0.33-1.38)) and, to a lesser extent, when adipokines (i.e. ß WC: 0.73 (0.14-1.32)) and skeletal maturation (i.e. ß WC: 0.65 (0.10-1.20)) were added. CONCLUSION: In GOCS children, AR at a younger age predicts higher metabolic risk at 7 years; these associations are mostly explained by increased adiposity, but adipose dysfunction and accelerated skeletal maturation also have a role.
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Adiposidade , Síndrome Metabólica/epidemiologia , Obesidade Infantil/epidemiologia , Circunferência da Cintura , Aumento de Peso , Adiponectina/sangue , Fatores Etários , Idade de Início , Biomarcadores/sangue , Glicemia/metabolismo , Composição Corporal , Índice de Massa Corporal , Criança , Desenvolvimento Infantil , Chile/epidemiologia , HDL-Colesterol/sangue , Estudos de Coortes , Feminino , Humanos , Leptina/sangue , Lipoproteínas HDL/sangue , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/prevenção & controle , Obesidade Infantil/sangue , Obesidade Infantil/prevenção & controle , Fatores de Risco , Triglicerídeos/sangueRESUMO
In 12 July 2012, the Chilean Senate approved the Law of Food Labeling and Advertising, resulting from the joint efforts of a group of health professionals, researchers and legislators who proposed a regulatory framework in support of healthy diets and active living. Its goal was to curb the ongoing epidemic increase of obesity and non-communicable diseases. Two actions included: (i) improving point of food purchase consumer information by incorporating easy-to-understand front-of-packages labeling and specific messages addressing critical nutrients, and (ii) decreasing children's exposure to unhealthy foods by restricting marketing, advertising and sales. We summarize the work related to the law's release and discuss the conclusions reached by the various expert committees that were convened by the Ministry of Health to guide the development of the regulatory norms. Throughout the process, the food industry has overtly expressed its disagreement with the regulatory effort. The final content of the regulatory norms is still pending; however there are suggestions that its implementation will be delayed and might be modified based on the industry lobbying actions. These lessons should contribute to show the need of anticipating and addressing potential barriers to obesity-prevention policy implementation, particularly with respect to the role of the private sector.
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Publicidade/legislação & jurisprudência , Rotulagem de Alimentos/legislação & jurisprudência , Promoção da Saúde , Obesidade/epidemiologia , Obesidade/prevenção & controle , Bebidas , Chile/epidemiologia , Indústria Alimentícia/legislação & jurisprudência , Serviços de Alimentação/legislação & jurisprudência , Humanos , Política Nutricional , Tamanho da Porção , Instituições Acadêmicas , TelevisãoRESUMO
BACKGROUND: Healthy growth in utero and after birth is fundamental for lifelong health and wellbeing. The World Health Organization (WHO) recently published standards for healthy growth from birth to 6 years of age; analogous standards for healthy fetal growth are not currently available. Current fetal growth charts in use are not true standards, since they are based on cross-sectional measurements of attained size under conditions that do not accurately reflect normal growth. In most cases, the pregnant populations and environments studied are far from ideal; thus the data are unlikely to reflect optimal fetal growth. A true standard should reflect how fetuses and newborns 'should' grow under ideal environmental conditions. OBJECTIVE: The development of prescriptive intrauterine and newborn growth standards derived from the INTERGROWTH-21(st) Project provides the data that will allow us for the first time to establish what is 'normal' fetal growth. METHODS: The INTERGROWTH-21(st) study centres provide the data set obtained under pre-established standardised criteria, and details of the methods used are also published. DESIGN: Multicentre study with sites in all major geographical regions of the world using a standard evaluation protocol. RESULTS: These standards will assess risk of abnormal size at birth and serve to evaluate potentially effective interventions to promote optimal growth beyond securing survival. DISCUSSION: The new normative standards have the potential to impact perinatal and neonatal survival and beyond, particularly in developing countries where fetal growth restriction is most prevalent. They will help us identify intrauterine growth restriction at earlier stages of development, when preventive or corrective strategies might be more effective than at present. CONCLUSION: These growth standards will take us one step closer to effective action in preventing and potentially reversing abnormal intrauterine growth. Achieving 'optimal' fetal growth requires that we act not only during pregnancy but that we optimize the maternal uterine environment from the time before conception, through embryonic development until fetal growth is complete. The remaining challenge is how 'early' will we be able to act, now that we can better monitor fetal growth.
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Desenvolvimento Infantil , Desenvolvimento Fetal , Gráficos de Crescimento , Recém-Nascido/crescimento & desenvolvimento , Estudos Multicêntricos como Assunto , Criança , Pré-Escolar , Feminino , Retardo do Crescimento Fetal/diagnóstico , Retardo do Crescimento Fetal/etiologia , Retardo do Crescimento Fetal/prevenção & controle , Humanos , Lactente , Recém-Nascido de Baixo Peso/crescimento & desenvolvimento , Recém-Nascido Prematuro/crescimento & desenvolvimento , Estudos Multicêntricos como Assunto/métodos , Estudos Multicêntricos como Assunto/normas , GravidezRESUMO
OBJECTIVES: The effectiveness of community level interventions depends to a great extent on adherence. Currently, information on factors related to adherence in older adults from developing countries is scarce. Our aim was to identify factors associated to adherence to a physical activity intervention in older adults from a post-transitional middle income country. DESIGN, SETTING AND PARTICIPANTS: Using a combination of quantitative and qualitative methods we studied 996 older Chilean subjects (65-67.9 years at baseline) with low to medium socioeconomic status from 10 health centers randomized to receive a physical activity intervention as part of the CENEX cluster trial (ISRCTN48153354). MEASUREMENTS: Using a multilevel regression model, the relationship between adherence (defined a priori as attendance at a minimum of 24 physical activity classes spread over at least 12 months) and individual, intervention-related and contextual factors was evaluated. We also conducted 40 semi-structured interviews with older adults (n=36) and instructors (n=4). Transcripts of the interviews were analyzed using content analysis to identify barriers and facilitators to adherence. RESULTS: Adherence to physical activity intervention was 42.6% (CI 95% 39.5 to 45.6). Depression, diabetes mellitus, percentage of impoverished households and rate of arrests for violent crimes in the neighborhood predicted less adherence (p<0.05) while being retired, participation in physical activity prior to the intervention, and green areas per habitant were positively associated with adherence (p<0.05). The qualitative interviews identified three primary barriers to adherence: current health problems, lack of time due to commitments for caring for family members, and being employed, and two primary facilitators to adherence: the health benefits attributed to the intervention and the opportunity the classes provided for social interaction with others. CONCLUSION: In order to enhance effectiveness of community exercise interventions, strategies to improve participation should be targeted to older adults from deprived areas and those with psychological and medical conditions.
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Emprego , Exercício Físico , Família , Nível de Saúde , Cooperação do Paciente , Pobreza , Características de Residência , Idoso , Cuidadores , Chile , Crime , Países em Desenvolvimento , Meio Ambiente , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Relações Interpessoais , Entrevistas como Assunto , Masculino , Satisfação do Paciente , Pesquisa Qualitativa , Análise de RegressãoRESUMO
Latin America has experienced rapid demographic, epidemiological and nutrition changes that have successfully contributed to decreasing undernutrition, but concomitantly have resulted in an increase of obesity and associated conditions; in this paper we propose that policies to address undernutrition have not adapted at a sufficiently rapid pace to address the emerging challenges. Taking Chile as an example we show that health promotion policies, implemented only when the obesity epidemic was well advanced, have succeeded in establishing effective regulatory frameworks and in implementing national large-scale programs for treatment; however, they have been insufficient in preventing obesity. The main lessons learned are: (1) Failure to monitor existing malnutrition programs for changing needs and true effectiveness can have unintended consequences. (2) Institutions and professionals working in nutrition and health need to assess changing scenarios and redefine their priorities for action accordingly. (3) There is a need to provide updated information to decision makers, program planners and to the population at large on how to promote and achieve healthy food consumption and active living considering local context. Timely policies and interventions to address these issues may contribute to the prevention of the obesity epidemic in transitional countries, particularly among low socioeconomic groups.
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Dieta , Desnutrição/prevenção & controle , Política Nutricional , Obesidade/etiologia , Chile , Promoção da Saúde , Humanos , Disseminação de InformaçãoRESUMO
OBJECTIVE: To assess the impact of a 6 months nutrition education and physical activity intervention on primary school children through changes in adiposity and physical fitness. DESIGN: Longitudinal school-based controlled evaluation study. SUBJECTS: Children from 1st to 8th grade, 2141 in intervention and 945 in control schools. INTERVENTION: Nutrition education for children and parents, 'healthier' kiosks, 90 min of additional physical activity (PA) weekly, behavioral PA program and active recess. MEASUREMENTS: Adiposity indices (BMI, BMI Z-score, triceps skinfold thickness (TSF), waist circumference and physical fitness (20 m shuttle run test and lower back flexibility). RESULTS: Positive effect on adiposity indices (except TSF) was observed in boys (P<0.001 for BMI Z), while both physical fitness parameters increased significantly in both boys (P<0.001 for each test) and girls (P<0.0001 for each test). A differential effect in BMI Z was observed according to baseline nutritional status. CONCLUSIONS: This intervention showed a robust effect on physical fitness in both genders and decreased adiposity only in boys.
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Educação em Saúde/métodos , Obesidade/prevenção & controle , Instituições Acadêmicas , Antropometria , Índice de Massa Corporal , Criança , Ciências da Nutrição Infantil/educação , Chile , Dieta , Feminino , Seguimentos , Humanos , Masculino , Educação Física e Treinamento , Aptidão FísicaRESUMO
Divalent metal transporter #1 (DMT1) is responsible for intestinal nonheme Fe apical uptake. However, DMT1 appears to have an additional function in Cu transport in intestinal cells. Because the liver has an essential role in body Cu homeostasis, we examined the potential involvement of Cu in the regulation of DMT1 expression and activity in Hep-G2 cells. Cells exposed to 10 microM Cu exhibited a 22-fold increase in Cu content and a twofold decrease in Fe content compared with cells maintained in 0.4 microM Cu. (64)Cu uptake in Cu-deficient Hep-G2 cells showed a twofold decrease in K(m) compared with cells grown in 10 microM Cu. The decreased K(m) may represent an adaptive response to Cu deficiency. Cells treated with >50 microM Cu, showed an eightfold increase in cytosolic metallothionein. DMT1 protein decreased (35%), suggesting that intracellular Cu caused a reduction of DMT1 protein levels. Our data indicate that, as a result of Cu overload, Hep-G2 cells reduced their Fe content and their DMT1 protein levels. These findings strongly suggest a relationship between Cu and Fe homeostasis in Hep-G2 cells in which Cu accumulation downregulates DMT1 activity.
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Cobre/metabolismo , Cobre/toxicidade , Ferro/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Linhagem Celular Tumoral , Cobre/análise , Cobre/farmacocinética , Radioisótopos de Cobre , Meios de Cultura/química , Humanos , Proteínas de Ligação ao Ferro/metabolismo , Metalotioneína/metabolismo , Metais/metabolismo , Concentração OsmolarRESUMO
OBJECTIVE: To compare trends in prevalence of overweight and obesity among Chilean children using three different criteria. METHODS: Descriptive cross-sectional school-based study to analyse these trends in 6-y-old boys and girls who entered first grade in 1987, 1990, 1993, 1996 and 2000. Gender-specific prevalence of overweight and obesity were determined with three criteria: weight for height (W-H) Z-scores compared to NCHS 1977; present reference used by the Ministry of Health; and body mass index (BMI) compared to the revised US CDC Growth Charts with cut-off values of P85-95 and P-95 and IOTF reference with cut-offs extrapolated from an adult BMI of 25 and 30. RESULTS: The prevalence of overweight determined by W-H (WHO) increased from 15% in 1987 to 20% in 2000 for boys and from 17.2 to 21.8% for girls. With BMI-CDC, the increase was from 13.2 to 19.2% for boys and 12 to 18.5% for girls. With BMI-IOTF, rates were very similar. Prevalence of obesity using W-H (WHO) increased from 6.5% in 1987 to 17% in 2000 for boys and from 7.8 to 18.6% for girls. Using BMI-CDC, the increase was from 5.1 to 14.7% for boys and from 4 to 15.8% for girls; using BMI-IOTF prevalence estimates were much lower. CONCLUSIONS: Obesity prevalence in children has increased over time, and trends are similar independent of criteria. The reference used to define prevalence is important since it provides different estimates. Policy makers should be aware that a spurious drop in prevalence may appear if the IOTF reference is compared to the other criteria.
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Obesidade/epidemiologia , Estatura/fisiologia , Índice de Massa Corporal , Peso Corporal/fisiologia , Criança , Pré-Escolar , Chile , Estudos Transversais , Feminino , Humanos , MasculinoRESUMO
Essential fatty acids are structural components of all tissues and are indispensable for cell membrane synthesis; the brain, retina and other neural tissues are particularly rich in long-chain polyunsaturated fatty acids (LC-PUFA). These fatty acids serve as specific precursors for eicosanoids, which regulate numerous cell and organ functions. Recent human studies support the essential nature of n-3 fatty acids in addition to the well-established role of n-6 essential fatty acids in humans, particularly in early life. The main findings are that light sensitivity of retinal rod photoreceptors is significantly reduced in newborns with n-3 fatty acid deficiency, and that docosahexaenoic acid (DHA) significantly enhances visual acuity maturation and cognitive functions. DHA is a conditionally essential nutrient for adequate neurodevelopment in humans. Comprehensive clinical studies have shown that dietary supplementation with marine oil or single-cell oil sources of LC-PUFA results in increased blood levels of DHA and arachidonic acid, as well as an associated improvement in visual function in formula-fed infants matching that of human breast-fed infants. The effect is mediated not only by the known effects on membrane biophysical properties, neurotransmitter content, and the corresponding electrophysiological correlates but also by a modulating gene expression of the developing retina and brain. Intracellular fatty acids or their metabolites regulate transcriptional activation of gene expression during adipocyte differentiation and retinal and nervous system development. Regulation of gene expression by LC-PUFA occurs at the transcriptional level and may be mediated by nuclear transcription factors activated by fatty acids. These nuclear receptors are part of the family of steroid hormone receptors. DHA also has significant effects on photoreceptor membranes and neurotransmitters involved in the signal transduction process; rhodopsin activation, rod and cone development, neuronal dendritic connectivity, and functional maturation of the central nervous system.
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Encéfalo/crescimento & desenvolvimento , Olho/crescimento & desenvolvimento , Ácidos Graxos Essenciais/farmacologia , Ácidos Graxos Essenciais/fisiologia , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Eletrofisiologia , Olho/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica , Humanos , Recém-Nascido , Neurônios/efeitos dos fármacos , Neurônios/fisiologiaRESUMO
The aim of this study was to determine whether total copper or soluble copper concentration is associated with gastrointestinal signs and symptoms. Forty-five healthy adult women (18-55 years of age), living in Santiago, Chile, ingested tap water with 5 mg/L of copper containing different ratios of soluble copper (copper sulfate) and insoluble copper (copper oxide) over a 9-week period. Three randomized sequences of the different copper ratios (0:5, 1:4, 2:3, 3:2, and 5:0 mg/L) were followed. Subjects recorded their water consumption and gastrointestinal symptoms daily on a special form. Mean water consumption was similar among groups. Serum copper levels, ceruloplasmin, and activities of liver enzymes were within normal limits. No differences were detected between the means of biochemical parameters at the beginning and at the end of the study. Twenty subjects presented gastrointestinal disturbances at least once during the study, 9 suffered diarrhea (with or without abdominal pain and vomiting), and the other 11 subjects reported abdominal pain, nausea, or vomiting. No differences were found in incidence of abdominal pain, nausea, vomiting, and diarrhea regardless of the ratio of copper sulfate to copper oxide. In conclusion, both copper sulfate (a soluble compound) and copper oxide (an insoluble compound) have comparable effects on the induction of gastrointestinal manifestations, implying that similar levels of ionic copper were present in the stomach.