Prevalence of metabolic syndrome in children aged 5-9 years from southwest colombia: a cross-sectional study.

BACKGROUND: Exploration of cardiometabolic alterations in the pre-adolescent stage is necessary to characterize possible patterns for matabolic syndrome (MetS) in the earliest stages of the life. However, defining specific cutoff points for metabolic and vascular markers represents a complex task in pre-adolescent populations. This study aimed to estimate the prevalence of MetS and its components in children aged 5-9 years old by using the MetS definition for adolescents with the lowest cut-off points, and evaluate its relationship with overweight and socio-demographic determinants. METHODS: A total of 494 children were evaluated. Multivariate models with filtered variables in preliminary univarite analyses were built to find predictive factors of MetS and its components. RESULTS: The prevalence of MetS was 8.7% in the studied children. Multivariate models showed that age, overweight and low socioeconomic stratum were associated with MetS; low high-density lipoprotein cholesterol was not significantly associated with any variable; high triglycerides were positively associated with age, overweight and inversely associated with kilocalories/day; female gender was the only variable significantly associated with high fasting glucose (inverse association); and age, gender and overweight were significant factors for increased waist circumference. In the case of high blood pressure, no variable was classified to the multivariate analysis. CONCLUSION: This study showed disturbing figures regarding cardiometabolic risk in the children based on comparisons with studies in adolescents. Further studies are needed to confirm the utility of the de Ferranti Mets definition in children.

Circulating hepcidin in type 2 diabetes: A multivariate analysis and double blind evaluation of metformin effects.

SCOPE: Very few studies have evaluated serum hepcidin in patients with type 2 diabetes and they have reported conflicting results. In addition, the effect of antidiabetic drugs on circulating hepcidin has not been explored so far. The aims of the study were to evaluate hepcidin concentrations and hepcidin/ferritin ratio in type 2 diabetes subjects and healthy non-diabetic controls and to evaluate the effect of metformin on hepcidin concentrations. METHODS AND RESULTS: Study 1: Cross-sectional multivariate study of 239 non-diabetic individuals and 65 people with type 2 diabetes. The multivariate analysis included covariates of chronic inflammation, BMI, pharmacological treatment, menopausal status and insulin resistance. Study 2: Randomized, double-blinded, placebo-controlled 4-month trial metformin compared to placebo among 36 type 2 diabetic patients. In both groups diet was controlled by maintaining a hypocaloric intake across the trial. Hepcidin levels were significantly lower in patients with type 2 diabetes than in non-diabetic individuals either in crude or adjusted regression models (P<0.05). Hepcidin decreased in both arms of the trial (Placebo, p = 0.004; metformin, p = 0.022). CONCLUSION: Circulating hepcidin was significantly and independently lower in type 2 diabetes. Metformin treatment is not associated with reductions in hepcidin but hypocaloric diet could be involved.

Waist:height ratio, waist circumference and metabolic syndrome abnormalities in Colombian schooled adolescents: a multivariate analysis considering located adiposity.

Very few large studies in Latin America have evaluated the association between waist:height ratio (W-HtR) and cardiometabolic risk in children and adolescents. Further, multivariable analyses verifying the independence of located subcutaneous fat have not been conducted so far. The aim of this study was to evaluate the associations of W-HtR and waist circumference (WC) with metabolic syndrome abnormalities and high LDL-cholesterol levels in schooled adolescents before and after adjusting for trunk skinfolds and BMI. The sample consisted of 831 boys and 841 girls aged 10-17 years. Biochemical, blood pressure and anthropometrical variables were measured. Age- and sex-specific quartiles of W-HtR and WC were used in Poisson regression models to evaluate the associations. High WC values (highest quartile v. quartiles 1-3) were associated with high TAG levels in both sexes (prevalence ratio, boys: 2·57 (95 % CI 1·91, 3·44); girls: 1·92 (95 % CI 1·49, 2·47); P0·05). High W-HtR (highest quartile v. quartiles 1-3) was only independently associated with high TAG in female adolescents (1·99 (95 % CI 1·55, 2·56); P<0·05). In conclusion, WC showed better association with cardiometabolic risk than W-HtR in the children of this study. This observation does not support W-HtR as a relevant adiposity marker for cardiovascular and metabolic risk in adolescence.

Impact of oxidative stress during pregnancy on fetal epigenetic patterns and early origin of vascular diseases.

Epidemiological studies have led scientists to postulate the developmental origins of health and disease hypothesis for noncommunicable diseases such as diabetes, cardiovascular diseases, hypertension, and obesity. However, the cellular and molecular mechanisms involved in the development of these diseases are not well understood. In various animal models, it has been observed that oxidative stress during pregnancy is associated with the early development of endothelial dysfunction in offspring. This phenomenon suggests that endothelial dysfunction may initiate in the uterus and could lead to increased risk of cardiovascular disease later in life. Currently, it is known that many of the fetal adaptive responses to environmental factors are mediated by epigenetic changes in the genome, especially by the degree of methylation in cytosines in the promoter regions of genes. These findings suggest that the establishment of a particular epigenetic pattern in the genome may be generated by oxidative stress.

Relationship between maternal and newborn endothelial function and oxidative stress.

OBJECTIVE: To evaluate the Relationship between maternal and newborn endothelial function and oxidative stress. METHODS: Forty-three pregnant women and their offspring were evaluated. As markers of endothelial function, the flow-mediated dilation (FMD) was measured in pregnant women in the second and third trimesters, and nitric oxide (NO) was quantified in the endothelial cells of the umbilical cord vein. Malondialdehyde (MDA), as a marker of oxidative stress, was measured in the maternal plasma (second and third trimesters) and plasma from umbilical cord blood. Gestational age and birth weight were recorded. Correlations between variables were estimated, and adjustments were made for specific gestational week of measurement, gestational age at birth, and complications during pregnancy and/or at delivery. RESULTS: Maternal FMD at second trimester correlated positively with newborn MDA, although with marginal significance (P = 0.090). The change in maternal FMD was positively correlated with newborn NO (P = 0.039), although adjustment for gestational age and specific week of gestation attenuated this relationship (P = 0.070). Maternal MDA at second trimester correlated positively with newborn MDA independently of gestational age at birth, specific week of gestation of the measurement, and having complications during pregnancy or at delivery (P = 0.032). After adjustments, the change in maternal MDA correlated with newborn MDA but marginally (P = 0.077). CONCLUSION: Study findings suggest that under physiological conditions, enhanced endothelial function and/or oxidative stress in the mother may impact on normal fetal development. Future studies are recommended, employing larger sample sizes, a more extensive set of markers of oxidative stress, and comparisons of complicated versus normal pregnancies.

Evaluation of the relationship between self-reported physical activity and metabolic syndrome and its components in apparently healthy women.

INTRODUCTION: The metabolic syndrome, a set of metabolic anomalies that include insulin resistance, central obesity, dyslipidemia, hypertension and inflammation, is an important tool to explore factors associated to cardiometabolic disease. OBJECTIVE: The aim of this study was to evaluate the relationship of the levels of self-reported physical activity and the International Physical Activity Questionnaire items and the metabolic syndrome and the variables related to cardiovascular risk in 89 women. MATERIALS AND METHODS: The short version of International Physical Activity Questionnaire was applied to classify participating subjects into three categories: insufficient, sufficient and very active physical activity. The metabolic syndrome was assessed according to the International Diabetes Federation criteria. Biochemical and anthropometrical parameters were measured . RESULTS: Twenty-two participants (23%) presented metabolic syndrome and 66 women (74.2%) were classified in the insufficient physical activity category. No association was found between insufficient physical activity and metabolic syndrome . Inverse correlations were found among the days and minutes per week of physical activity of moderate-intensity, waist circumference ( r =-0.327, and r =-0.313, p<0.005, respectively), and body mass index ( r =-0.262, and r =-0.218, p<0.05, respectively). CONCLUSION: A high prevalence of insufficient physical activity was found in the study participants, but this was not associated with metabolic syndrome . Moderate but not vigorous physical activity items from the International Physical Activity Questionnaire correlated inversely with anthropometrical markers related to cardiovascular risk.

Evaluation of the relationship between self-reported physical activity and metabolic syndrome and its components in apparently healthy women / Evaluación de la relación de actividad física autorreportada con el síndrome metabólico y sus componentes en mujeres aparentemente sanas

Introduction: The metabolic syndrome, a set of metabolic anomalies that include insulin resistance, central obesity, dyslipidemia, hypertension and inflammation, is an important tool to explore factors associated to cardiometabolic disease. Objective: The aim of this study was to evaluate the relationship of the levels of self-reported physical activity and the International Physical Activity Questionnaire items and the metabolic syndrome and the variables related to cardiovascular risk in 89 women . Materials and methods: The short version of International Physical Activity Questionnaire was applied to classify participating subjects into three categories: insufficient, sufficient and very active physical activity. The metabolic syndrome was assessed according to the International Diabetes Federation criteria. Biochemical and anthropometrical parameters were measured . Results: Twenty-two participants (23%) presented metabolic syndrome and 66 women (74.2%) were classified in the insufficient physical activity category. No association was found between insufficient physical activity and metabolic syndrome . Inverse correlations were found among the days and minutes per week of physical activity of moderate-intensity, waist circumference ( r =-0.327, and r =-0.313, p<0.005, respectively), and body mass index ( r =-0.262, and r =-0.218, p<0.05, respectively). Conclusion: A high prevalence of insufficient physical activity was found in the study participants, but this was not associated with metabolic syndrome . Moderate but not vigorous physical activity items from the International Physical Activity Questionnaire correlated inversely with anthropometrical markers related to cardiovascular risk .

Introducción. El síndrome metabólico, conjunto de anomalías metabólicas que incluyen resistencia a la insulina, obesidad central, dislipidemia, hipertensión e inflamación, es una herramienta importante para explorar los factores asociados a enfermedades cardiovasculares. Objetivo. El objetivo de este estudio fue evaluar la relación de los niveles autorreportados de actividad física y los elementos del Cuestionario Internacional de Actividad Física ( International Physical Activity Questionnaire ), con el síndrome metabólico y las variables relacionadas con el riesgo cardiovascular en 89 mujeres. Materiales y métodos. La versión corta del Cuestionario Internacional de Actividad Física se aplicó para clasificar a los sujetos en tres categorías: actividad física insuficiente, suficiente y muy activa. El síndrome metabólico se evaluó según los criterios de la Federación Internacional de Diabetes y se midieron los parámetros bioquímicos y antropométricos. Resultados. Veintidós participantes (23 %) presentaron síndrome metabólico y 66 mujeres (74,2 %) fueron clasificadas en la categoría de actividad física insuficiente. No se encontró asociación entre la actividad física insuficiente y el síndrome metabólico. Se encontraron correlaciones inversas entre los días y minutos de actividad física de moderada intensidad por semana con la circunferencia de cintura ( r =-0,327, y r =-0,313, p<0,005, respectivamente) y el índice de masa corporal ( r =-0,262, y r =-0,218, p<0,05, respectivamente). Conclusión. Una alta prevalencia de actividad física insuficiente se encontró en las participantes en el estudio, pero esto no se asoció con el síndrome metabólico. Los elementos de la actividad física moderada del Cuestionario Internacional de Actividad Física, pero no así los de actividad vigorosa, se correlacionan inversamente con marcadores antropométricos relacionados con riesgo cardiovascular.

Association of self-reported familial history of cardiometabolic disease with metabolic syndrome in apparently healthy urban Colombian men.

OBJECTIVES: Evidence about the relationship between familial history (FH) of cardiometabolic disease (CMD) and metabolic syndrome (MetS) in Latin American populations is scarce. The aim of this study was to evaluate the relationship of FH of CMD and of dyslipidemia and obesity with MetS in healthy men. METHODS: One-hundred-twenty one individuals were recruited. Waist circumference and blood pressure were measured by a trained researcher using standard techniques. Glycemia and lipid profile were determined by colorimetric assays. A survey to record personal data and family antecedents in siblings, aunts/uncles, parents, and grandparents was conducted by trained interviewers. RESULTS: Individuals having three or more familial antecedents were associated with high triglycerides level even after adjusting by age, sedentarism, fat and carbohydrates intake, and alcohol consumption. After adjusting for the same variables, FH of dyslipidemia and hypertension was also associated with high triglycerides levels and elevated waist circumference, respectively. The FH of stroke was associated with high blood pressure after adjusting for the rest of familial antecedents, and with MetS in all adjustment models. DISCUSSION: the findings of association of this study together with the previous reports are evidence of the importance of hereditary component as independent predictor of cardiovascular risk factors and its clustering, as well as of possible specific association patterns between FH of CMD and MetS depending on evaluated population in terms of ethnic groups and geographic region. Further studies are required in other populations, as well as exploration of genetic markers of CMD regarding to MetS.

Early atherosclerotic lesions and post-mortem serum cholesterol level in a group of Colombian children / Lesiones ateroscleróticas tempranas y nivel de colesterol post mórtem en un grupo de niños colombianos

Introduction: Atherosclerosis is an asymptomatic chronic disease, which begins at early age and is difficult to detect during this stage. Prospective studies suggest a causal relationship between total serum cholesterol levels during childhood and early adolescence and the development of cardiovascular diseases in adulthood. Objective: The aim of this study was to evaluate the prevalence of early atherosclerotic lesions in the aorta artery of children and its relationship with post-mortem serum cholesterol levels. Material and methods: Post-mortem samples of blood and aorta were taken from 43 subjects aged less than 17 years old. Histopathological analysis (intimal thickening and inflammatory infiltrates) of the thoracic aorta and measurement of total serum cholesterol were performed. Results: The analysis showed thickening of the intima and lymphocyte infiltrates in 93% of children, and macrophage infiltrates in 79.1% of cases. A relationship between the highest terciles of total serum cholesterol levels and the presence of multiple lesions in the aorta wall was found (P<0.05). Conclusion: This group of children had a high prevalence of early inflammatory atherosclerotic lesions positively related with serum cholesterol levels. To our knowledge this study represents the first report of a relationship between post-mortem total serum cholesterol levels and pathological findings of macrophages and lymphocytes infiltrates in the aorta wall.

Introducción. La aterosclerosis es una enfermedad crónica asintomática que se inicia a edad temprana y es de difícil detección en esta etapa. Los estudios prospectivos sugieren una relación causal entre el nivel de colesterol sérico total en la niñez y la adolescencia, y el desarrollo de enfermedades cardiovasculares en la adultez. Objetivo. El objetivo de este estudio fue evaluar, post mórtem, la prevalencia de lesiones ateroscleróticas tempranas en la arteria aorta de niños y su relación con los niveles de colesterol. Materiales y métodos. Se tomaron muestras de sangre y de aorta de 43 sujetos con edades menores de 17 años. Se hizo el análisis histopatológico (engrosamiento de la íntima e infiltrado inflamatorio) de la aorta torácica y la medición de colesterol en suero. Resultados. El análisis mostró engrosamiento de la íntima e infiltrado linfocitario en 93 % de los niños, e infiltrado de macrófagos en 79,1 %. Se encontró relación entre los terciles superiores de colesterol sérico y la presencia de múltiples lesiones en la pared de la aorta (p<0,05). Conclusión. Este grupo de niños presentó una alta prevalencia de lesiones ateroscleróticas inflamatorias tempranas relacionada positivamente con niveles de colesterol sérico. Para nuestro conocimiento, este estudio representa el primer reporte de la relación entre el colesterol sérico y los hallazgos histopatológicos de infiltrado de macrófagos y linfocitos en la pared de la aorta, post mórtem.

Dietary zinc intake is inversely associated to metabolic syndrome in male but not in female urban adolescents.

OBJECTIVE: To evaluate the relationship of copper and zinc dietary intakes with metabolic syndrome (MetS) in adolescents. METHODS: The sample consisted of 1,311 adolescents aged 11-16 years, and MetS definition by de Ferranti et al. was used. Nutritional intakes, anthropometrical and biochemical markers were measured. RESULTS: In males, highest quartile of zinc intake was inversely associated with MetS without and with adjustment by covariables. Without adjustment, highest quartile of copper intake was inversely associated (marginal significance) with MetS, but with adjustment, the relationship was not maintained. Likewise in male gender, elevated waist circumference was the only MetS component inversely associated with highest quartiles of zinc (without and with adjustment) and copper (significant in crude analysis and marginal significant in adjustment by covariables) intakes. In the girls, only waist circumference was significant and inversely associated with highest quartiles of zinc and copper intakes but the association did not remain significant after adjustments. DISCUSSION: In the adolescents of this study, zinc intake could be more associated to a clustering of anthropometric, vascular, and metabolic alterations than to these alterations separately, and also it is inversely related to this clustering (MetS). However, studies in other populations are necessary to confirm and explain the finding of exclusive association zinc intake-MetS in male gender adolescents. Further research is required to explore biomarkers of physiological processes (antioxidant function, blood flow regulation, and epigenetic modulation dependent of zinc) in relation to zinc intake and MetS in pediatric and adult populations.

Nutrients intake as determinants of blood lead and cadmium levels in Colombian pregnant women.

OBJECTIVE: To evaluate the relationship between nutrients intake in the first trimester of pregnancy and blood levels of lead and cadmium during the first and third trimesters of gestation. METHODS: A total of 381 pregnant women were enrolled. Blood lead and cadmium were measured using electrothermal atomic absorption spectrometry, and dietary intake was assessed using 24-h recall questionnaire. RESULTS: Lead levels in the first trimester were negatively correlated with cadmium levels in the two trimesters, and levels of both metals correlated positively in the third trimester. Zinc and calcium intakes were negatively associated with blood lead during third trimester. Thiamine and folic acid intakes were negatively and positively associated (respectively) with blood lead at third trimester with marginal significance. Fat, niacin, and vitamin B12 intakes were significantly and positively associated with blood cadmium at first trimester. Folic acid and zinc intakes showed positive and marginally significant associations with blood cadmium without adjustments. At third trimester, blood cadmium was negatively associated to ascorbic acid intake, and positively associated with iron intake with a marginal significance. CONCLUSIONS: Possible acute and late effects of nutrients intake in blood lead and cadmium levels could be related with associations exclusively observed in the first and third trimester. This study represents the first exploration of relationships among a wide range of nutrients intake in the first trimester of pregnancy with blood lead and cadmium in first and third trimester of gestation. Further studies are required to confirm the findings mentioned herein.

Adiposity markers and cardiovascular risk in urban Colombian adolescents: heterogeneity in association patterns.

OBJECTIVE: The aim of this study was to evaluate the relationship of tricipital (TS), abdominal (AS), subscapular (SS), and suprailiac (SIS) skinfolds, Body Mass Index (BMI), and Waist Circumference (WC) with 1) variables related to cardiovascular risk (CVR) and 2) the clustering of cardiovascular risk factors (CVRF) - referenced pediatric cut-off points - in a multivariate analysis. MATERIALS/METHODS: The sample was 1672 adolescents. Glucose, lipid profile, blood pressure and anthropometric variables were measured. RESULTS: Adjusting for age, gender, and caloric intake, the highest quartile (Q4) of adiposity markers was associated to Q4 of biochemical and blood pressure variables. However, the association was not found for WC, SS and TS with glucose, and for diastolic blood pressure (DBP) with TS, SS, and SIS. Triglycerides Q4 was related to Q4 of SS, AS, and SIS after further adjustments, as well as HDL cholesterol (HDL-C) Q1 with Q4 of SS and AS. Glucose Q4 was associated to BMI, AS (Not adjusting for BMI and SIS), and SIS Q4 (Not adjusting for BMI and TS). LDL-Cholesterol (LDL-C) Q4 was associated to TS and SS Q4. The associations of LDL-C Q4 and HDL-C Q1 with WC Q4 were not significant after further adjustments. All the adiposity markers, except WC and TS, were associated to CVRF clustering in all the adjustments. CONCLUSIONS: In the adolescents, subcutaneous fat from the trunk (SS, AS, SIS) was better and independently associated to CVR variables and with CVRF clustering than visceral fat (WC). Further research is required to explain the specificity in the described associations.

Early atherosclerotic lesions and post-mortem serum cholesterol level in a group of Colombian children.

INTRODUCTION: Atherosclerosis is an asymptomatic chronic disease, which begins at early age and is difficult to detect during this stage. Prospective studies suggest a causal relationship between total serum cholesterol levels during childhood and early adolescence and the development of cardiovascular diseases in adulthood. OBJECTIVE: The aim of this study was to evaluate the prevalence of early atherosclerotic lesions in the aorta artery of children and its relationship with post-mortem serum cholesterol levels. MATERIAL AND METHODS: Post-mortem samples of blood and aorta were taken from 43 subjects aged less than 17 years old. Histopathological analysis (intimal thickening and inflammatory infiltrates) of the thoracic aorta and measurement of total serum cholesterol were performed. RESULTS: The analysis showed thickening of the intima and lymphocyte infiltrates in 93% of children, and macrophage infiltrates in 79.1% of cases. A relationship between the highest terciles of total serum cholesterol levels and the presence of multiple lesions in the aorta wall was found ( P <0.05). CONCLUSION: This group of children had a high prevalence of early inflammatory atherosclerotic lesions positively related with serum cholesterol levels. To our knowledge this study represents the first report of a relationship between post-mortem total serum cholesterol levels and pathological findings of macrophages and lymphocytes infiltrates in the aorta wall.

Role of AKT / mTORC1 pathway in pancreatic β - cell proliferation / Participación de la vía de señalización AKT/mTORC1 en la proliferación de las células β del páncreas

Growth factors, insulin signaling and nutrients are important regulators of β-cell mass and function. The events linking these signals to regulation of β-cell mass are not completely understood. Recent findings indicate that mTOR pathway integrates signals from growth factors and nutrients with transcription, translation, cell size, cytoskeleton remodeling and mitochondrial metabolism. mTOR is a part of two distinct complexes; mTORC1 and mTORC2. The mammalian TORC1 is sensitive to rapamycin and contains Raptor, deptor, PRAS40 and the G protein β-subunit-like protein (GβL). mTORC1 activates key regulators of protein translation; ribosomal S6 kinase (S6K) and eukaryote initiation factor 4E-binding protein 1. This review summarizes current findings about the role of AKT/mTORC1 signaling in regulation of pancreatic β cell mass and proliferation. mTORC1 is a major regulator of β-cell cycle progression by modulation of cyclins D2, D3 and cdk4/cyclin D activity. These studies uncovered key novel pathways controlling cell cycle progression in β-cells in vivo. This information can be used to develop alternative approaches to expand β-cell mass in vivo and in vitro without the risk of oncogenic transformation. The acquisition of such knowledge is critical for the design of improved therapeutic strategies for the treatment and cure of diabetes as well as to understand the effects of mTOR inhibitors in β-cell function.

Factores de crecimiento y nutrientes son reguladores muy importantes de la masa y función de las células β, pero las vías de señalización que unen estas señales a estos procesos no han sido completamente elucidadas. Estudios recientes han demostrado que la proteína mTOR integra señales provenientes de factores de crecimiento y disponibilidad de nutrientes con procesos celulares como transcripción, traducción, organización del citoesqueleto y metabolismo mitocondrial. mTOR puede hacer parte de dos complejos diferentes, mTORC1 y mTORC2. En el complejo mTORC1, la proteina mTOR la cual es sensible a rapamicina y se encuentra asociada a las proteínas Raptor, G β L, deptor y PRAS40, activa reguladores claves en la síntesis de proteínas, tales como la proteína cinasa ribosomal S6 (S6K) y la proteína de unión al factor eucariótico de iniciación 4E. El presente trabajo recopila información reciente sobre la participación de la vía de señalización AKT/mTORC1 en la regulación de la proliferación y masa de las células β del páncreas. mTORC1 regula la progresión del ciclo celular en células β, mediante la modulación de los niveles de las ciclinas D2 y D3 y la actividad del complejo Cdk4/ ciclina D. Estos estudios que revelan nuevos puntos de control del ciclo celular en células β, pueden ser utilizados en el desarrollo de nuevos enfoques para expandir la masa de células β, sin el riesgo de inducir una transformación oncogénica. Los resultados relacionados en el presente trabajo aportan información muy valiosa para el desarrollo de nuevas estrategias terapéuticas para el tratamiento la diabetes tipo 2.

Body iron stores as predictors of insulin resistance in apparently healthy urban Colombian men.

The aim of this study was to evaluate body iron stores as predictors of insulin resistance. We developed a cross-sectional study among 123 men, 25-64 years of age and determined fasting plasma glucose, insulin, serum ferritin, and C-reactive protein levels. A survey was performed to record personal antecedents and family history of non-transmissible chronic diseases. Log-transformed ferritin levels was an independent predictor for log-transformed insulin resistance index assessed by homeostatic model assessment when body mass index or waist circumference were not included in multiple linear regression models. Sedentarism, heart attack family history, and log-C reactive protein levels were also significant predictors for insulin resistance. In conclusion, documented anthropometric predictors affect the significance of ferritin as a potential prediction variable for insulin resistance. Mechanisms of how body fat could influence ferritin levels should be evaluated. To our knowledge, this is the first evaluation of the relationship between body iron stores and insulin resistance in a Latin American population.

Role of AKT/mTORC1 pathway in pancreatic ß-cell proliferation.

Growth factors, insulin signaling and nutrients are important regulators of ß-cell mass and function. The events linking these signals to regulation of ß-cell mass are not completely understood. Recent findings indicate that mTOR pathway integrates signals from growth factors and nutrients with transcription, translation, cell size, cytoskeleton remodeling and mitochondrial metabolism. mTOR is a part of two distinct complexes; mTORC1 and mTORC2. The mammalian TORC1 is sensitive to rapamycin and contains Raptor, deptor, PRAS40 and the G protein ß-subunit-like protein (GßL). mTORC1 activates key regulators of protein translation; ribosomal S6 kinase (S6K) and eukaryote initiation factor 4E-binding protein 1. This review summarizes current findings about the role of AKT/mTORC1 signaling in regulation of pancreatic ß cell mass and proliferation. mTORC1 is a major regulator of ß-cell cycle progression by modulation of cyclins D2, D3 and cdk4/cyclin D activity. These studies uncovered key novel pathways controlling cell cycle progression in ß-cells in vivo. This information can be used to develop alternative approaches to expand ß-cell mass in vivo and in vitro without the risk of oncogenic transformation. The acquisition of such knowledge is critical for the design of improved therapeutic strategies for the treatment and cure of diabetes as well as to understand the effects of mTOR inhibitors in ß-cell function.

Factores de crecimiento y nutrientes son reguladores muy importantes de la masa y función de las células ß, pero las vías de señalización que unen estas señales a estos procesos no han sido completamente elucidadas. Estudios recientes han demostrado que la proteína mTOR integra señales provenientes de factores de crecimiento y disponibilidad de nutrientes con procesos celulares como transcripción, traducción, organización del citoesqueleto y metabolismo mitocondrial. mTOR puede hacer parte de dos complejos diferentes, mTORC1 y mTORC2. En el complejo mTORC1, la proteina mTOR la cual es sensible a rapamicina y se encuentra asociada a las proteínas Raptor, G ß L, deptor y PRAS40, activa reguladores claves en la síntesis de proteínas, tales como la proteína cinasa ribosomal S6 (S6K) y la proteína de unión al factor eucariótico de iniciación 4E. El presente trabajo recopila información reciente sobre la participación de la vía de señalización AKT/mTORC1 en la regulación de la proliferación y masa de las células ß del páncreas. mTORC1 regula la progresión del ciclo celular en células ß, mediante la modulación de los niveles de las ciclinas D2 y D3 y la actividad del complejo Cdk4/ ciclina D. Estos estudios que revelan nuevos puntos de control del ciclo celular en células ß, pueden ser utilizados en el desarrollo de nuevos enfoques para expandir la masa de células ß, sin el riesgo de inducir una transformación oncogénica. Los resultados relacionados en el presente trabajo aportan información muy valiosa para el desarrollo de nuevas estrategias terapéuticas para el tratamiento la diabetes tipo 2.

Inverse correlation between serum calcium and copper levels in male urban Colombian preschool children: relationships with anthropometry and age.

Copper and calcium are essential for human growth and development. The present study was conducted to evaluate the relationship between calcium and copper levels, as well as their relationship to age and anthropometry in 180 preschool children ages 2-5 years old. Serum copper levels were inversely correlated with age (r = -0.184, P = 0.032) and height (r = -0.175, P = 0.043) in the whole group and with height for age Z score only in male children (r = -0.291, P = 0.016). The correlation with age is not maintained when it is analyzed for gender. Serum calcium values in the total group were inversely correlated with weight (r = -0.153, P = 0.044) and weight for height Z score (r = -0.246, P = 0.001). No differences were found for gender in the levels of both metals. A negative relationship between serum calcium and copper was found only in male children (r = -0.339, P = 0.005). Studies are required in other populations and experimental designs that can explain an inverse relationship between serum calcium and copper levels.

[Association of risk factors for non transmissible chronic diseases with insuline sensitivity, in young adults in the city of Cali, Colombia]. / Relación entre los factores de riesgo de enfermedades crónicas no transmisibles y la sensibilidad a la insulina en adultos jóvenes de 18 a 39 años de la ciudad de Cali-Colombia.

The prevalence of insulin resistance and risk factors for chronic diseases is not known in Colombia. The purpose of the study was of determine the association of insulin resistance and risk of chronic diseases in young, apparently healthy adults. By convenience, 97 subjects, mean age of 24 years were studied. Family and personal history, anthropometrics, lipid profile, and a short insulin tolerance test was done to each subject to identify prevalence of insulin resistance and its association with risk factors. Plasma lipids and anthropometrics were within acceptable range. Insulin sensitivity was categorized as high, border high, border low and low. Out of 97 subjects 47 had altered sensitivity. Most women (68%) were classified as border low, and most men (60%) as low. There was a difference between these two categories in waist circumference and weight. Border low and low cases had not less than 3 risk factors but the total number of factors was not different within the 4 groups. More than 50% of cases had family history of chronic diseases, sedentary life and low C-HDL. There was a negative association between insulin sensitivity and fasting Glycaemia and positive with fasting triglycerides, BMI, Waist hip ratio and weight. Results suggest a surprisingly high prevalence of risk factors in a young group associated with altered insulin sensitivity. It may be possible to identify early indicators of risk and develop appropriate strategies for prevention.

[Evaluation of early manifestations of chronic no transmitted diseases risk in school population in Cali - Colombia]. / Evaluación de manifestaciones tempranas de riesgo para enfermedades crónicas no trasmisibles en población escolarizada de Cali - Colombia.

Similar to other countries in America, Colombia and the Department of Valle present changes in their population structure and mortality suggesting an advanced epidemiological transition status. Grouped, chronic diseases represent the principal cause of death in municipalities with high urban concentration. To identify associated factors of chronic conditions later in life, school children stratified by age, socio-economic level and gender were studied. By random sampling of 14 schools 2.807 children were examined to measure: anthropometry, work capacity, food intake, sexual maturation, blood pressure, and blood levels of glucose and lipids. Weight and height for all ages and gender were lower than international reference but higher than in previous studies. On the contrary body mass indicators were higher. Work capacity adjusted for body weight was higher in low income children. Mean age of menarche was 11,9 years. The relative peak of growth was 11 years for girls and 14 for boys. Maturity was reached at 12 years in women and 17 in men. Blood lipids were considered high and borderline high in a large proportion of the students, while 19.5% had systolic blood pressure > or = 120 mm. and 24% diastolic > or = 70. Intake of protein and energy was adequate, but diet was high in fat and sugar. There was not deficiency in macro nutrients but dietary intake of some minerals was low, specially iron and calcium. The findings indicate a population with unbalanced diet and disturbing high body mass and lipid concentration that could represent in the future an increase in the already high prevalence of chronic diseases.

Lipemia postprandial en adultos jóvenes de diferentes etnias en Colombia / Postprandial lipemia in Colombian young adults from different ethnias

La lipemia postprandial como factor asociado a aterogénesis esta con el desarrollo de Enfermedades Crónicas No Transmisibles (ECNT). Con el objetivo de determinar factores que modifican lipemia postprandial en respuesta a ingesta mixta de carbohidratos-lípidos en adultos jóvenes de diferentes etnias, se realizó estudio descriptivo no aleatorio con 51 sujetos (23.8±4 años) sanos, con registros de datos personales, clasificación étnica; Test Corto Insulina, Prueba de lipemia postprandial, cálculo de índice masa corporal (IMC) y Area Bajo la Curva (ABC) para evaluación postprandial. Alta porcentaje (80 por ciento) con antecedentes familiares de ECNT y sedentarismo. Los resultados mostraron promedios altos de ABC de glucosa, triglicéridos y Acidos Grasos No Esterificados (AGNE); el ABC de glucosa con diferencias por edad (p menor o igual 0.05), sin diferencias por etnia, género, IMC o sensibilidad a insulina. La curva de trigliceridemia mostró dos picos en mestizos (40 por ciento) y tres en negros (27 por ciento). Sujetos con patrón de cuatro picos tenían IMC elevado; igualmente fue mayor en blancos y mestizos que en negros (p<0.05); mayor en grupo mayores de 29 años y en hombres (p<0.05). El cambio de trigliceridemia sin diferencias por etnia, mayor en hombres (p<0.05) y en sujetos mayores (p<0.05). Correlación (r²= 0.70) entre IMC y trigliceridemia, entre IMC y cambio en trigliceridemia en etnias blancas y negra. Los AGNE descendieron hasta las 2 horas y a las 6-7h alcanzaron concentración mayor que la basal. ABC de Triglicéridos y AGNE mayores que lo reportado. Por alta correlación en casi todas las etnias IMC sería posible indicador de magnitud de trigliceridemia postprandial. Existe respuesta anormal a dieta de grasa, con liberación temprana de AGNE