Does Vitamin D play a role in the management of Covid-19 in Brazil?

The study discusses the possible role of adequate vitamin D status in plasma or serum for preventing acute respiratory infections during the Covid-19 pandemic. Our arguments respond to an article, published in Italy, that describes the high prevalence of hypovitaminosis D in older Italian women and raises the possible preventive and therapeutic role of optimal vitamin D levels. Based on literature review, we highlight the findings regarding the protective role of vitamin D for infectious diseases of the respiratory system. However, randomized controlled trials are currently lacking. Adequate vitamin D status is obtained from sun exposure and foods rich in vitamin D. Studies in Brazil have shown that hypovitaminosis D is quite common in spite of high insolation. Authors recommend ecological, epidemiological and randomized controlled trials studies to verify this hypothesis

A hepcidina como parâmetro bioquímico na avaliação da anemia por deficiência de ferro Hepcidin as a biochemical parameter for the assessment of iron deficiency anemia

A anemia por deficiência de ferro caracteriza-se como o mais prevalente problema nutricional em todo o mundo. Nesta revisão reuniu-se informações a respeito do metabolismo da hepcidina, avaliando-se seu valor como parâmetro bioquímico na anemia por deficiência de ferro. Realizou-se um levantamento bibliográfico nas bases de dados PUBMED e LILACS, período 2006-2010, referentes à hepcidina como um biomarcador para a regulação do metabolismo do ferro. Foram localizados 35 estudos publicados em revistas internacionais e um estudo sobre o assunto em revista nacional. A produção de hepcidina é regulada homeostaticamente pela anemia e hipóxia. Quando a oferta de oxigênio está inadequada ocorre diminuição do nível de hepcidina. Consequentemente, maior quantidade de ferro proveniente da dieta e dos estoques dos macrófagos e hepatócitos se tornam disponíveis. A hepcidina possui a função de se ligar à ferroportina, regulando a liberação do ferro para o plasma. Quando as concentrações de hepcidina estão baixas, as moléculas de ferroportina são expostas na membrana plasmática e liberam o ferro. Quando os níveis de hepcidina aumentam, a hepcidina liga-se às moléculas de ferroportina induzindo sua internalização e degradação, e o ferro liberado diminui progressivamente. Aparentemente o desenvolvimento do diagnóstico e terapia da anemia baseados no bioindicador hepcidina pode oferecer uma abordagem mais efetiva. Estudos epidemiológicos são necessários para comprovar o valor da hepcidina no diagnóstico diferencial das anemias, incluindo protocolos de amostragem para análise, com padronização similar às utilizadas em outras avaliações bioquímicas, e estabelecimento de pontos de corte para a expressão urinária e plasmática desse peptídeo.<br>Iron deficiency anemia is the most prevalent nutritional problem in the world. Information on the metabolism of hepcidin and its possible significance as a biochemical parameter for assessment of iron deficiency anemia is reported in this review. A literature review was carried out in the databases PubMed and LILACS, between 2006-2010, assessing hepcidin as a parameter for the regulation of iron metabolism. During this period 35 studies were published in international journals and one study in a Brazilian journal. The production of hepcidin is homeostatically regulated by anemia and hypoxia. When oxygen supply is inadequate the level of hepcidin decreases. Therefore, more iron from the diet and from the stock of macrophages and hepatocytes becomes available. Hepcidin links to ferroportin, regulating iron release to plasma. When the hepcidin concentrations are low, the molecules of ferroportin are exposed on the plasmatic membrane and release iron. When hepcidin levels increase, hepcidin binds to molecules of ferroportin inducing its internalization and degradation and iron release gradually decreases. Apparently, development of diagnosis and therapy for anemia based on the parameter hepcidin may provide a more effective approach. Large-studies are needed to demonstrate the importance of hepcidin for the differential diagnosis of anemia, including sample protocols for analysis, with standards similar to those used in other biochemical evaluations, as well as the definition of cut-off points for the plasma and urinary expression of this peptide

Cardiometabolic Risk Markers of Normal Weight and Excess Body Weight in Brazilian Adolescents

Excess body weight leads to a variety of metabolic changes and increases the risk for cardiovascular diseases (CVD) in adulthood. The objective of this study was to investigate the presence of risk markers for CVD among Brazilian adolescents of normal weight and with excess body weight. The markers included blood pressure, C-reactive protein, homocysteine, tumor necrosis factor alpha, fibrinogen, fasting insulin and glucose, homeostasis model assessment insulin resistance (HOMA-IR), leptin, total cholesterol, low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), and triglycerides. We calculated odds ratios (OR) using logistic regression and adjusted for the potential confounders such as age, sex, physical activity and socioeconomic background. Compared to normal weight subjects, overweight/obese adolescents were more likely to have higher systolic blood pressure (OR = 3.49, pThe accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Data_Sheet_1_The relationship between obesity-related H19DMR methylation and H19 and IGF2 gene expression on offspring growth and body composition.PDF

Background and objectiveImprinted genes are important for the offspring development. To assess the relationship between obesity-related H19DMR methylation and H19 and IGF2 gene expression and offspring growth and body composition.MethodsThirty-nine overweight/obese and 25 normal weight pregnant women were selected from the “Araraquara Cohort Study” according to their pre-pregnancy BMI. Fetal growth and body composition and newborn growth were assessed, respectively, by ultrasound and anthropometry. The methylation of H19DMR in maternal blood, cord blood, maternal decidua and placental villi tissues was evaluated by methylation-sensitive restriction endonuclease qPCR, and H19 and IGF2 expression by relative real-time PCR quantification. Multiple linear regression models explored the associations of DNA methylation and gene expression with maternal, fetal, and newborn parameters.ResultsH19DMR was less methylated in maternal blood of the overweight/obese group. There were associations of H19DMR methylation in cord blood with centiles of fetal biparietal diameter (BPD) and abdominal subcutaneous fat thickness and newborn head circumference (HC); H19DMR methylation in maternal decidua with fetal occipitofrontal diameter (OFD), HC, and length; H19DMR methylation in placental villi with fetal OFD, HC and abdominal subcutaneous fat thickness and with newborn HC. H19 expression in maternal decidua was associated with fetal BPD and femur length centiles and in placental villi with fetal OFD and subcutaneous arm fat. IGF2 expression in maternal decidua was associated with fetal BPD and in placental villi with fetal OFD.ConclusionTo our knowledge, this is the first study to demonstrate associations of imprinted genes variations at the maternal-fetal interface of the placenta and in cord blood with fetal body composition, supporting the involvement of epigenetic mechanisms in offspring growth and body composition.</p

Table_2_The relationship between obesity-related H19DMR methylation and H19 and IGF2 gene expression on offspring growth and body composition.docx

Background and objectiveImprinted genes are important for the offspring development. To assess the relationship between obesity-related H19DMR methylation and H19 and IGF2 gene expression and offspring growth and body composition.MethodsThirty-nine overweight/obese and 25 normal weight pregnant women were selected from the “Araraquara Cohort Study” according to their pre-pregnancy BMI. Fetal growth and body composition and newborn growth were assessed, respectively, by ultrasound and anthropometry. The methylation of H19DMR in maternal blood, cord blood, maternal decidua and placental villi tissues was evaluated by methylation-sensitive restriction endonuclease qPCR, and H19 and IGF2 expression by relative real-time PCR quantification. Multiple linear regression models explored the associations of DNA methylation and gene expression with maternal, fetal, and newborn parameters.ResultsH19DMR was less methylated in maternal blood of the overweight/obese group. There were associations of H19DMR methylation in cord blood with centiles of fetal biparietal diameter (BPD) and abdominal subcutaneous fat thickness and newborn head circumference (HC); H19DMR methylation in maternal decidua with fetal occipitofrontal diameter (OFD), HC, and length; H19DMR methylation in placental villi with fetal OFD, HC and abdominal subcutaneous fat thickness and with newborn HC. H19 expression in maternal decidua was associated with fetal BPD and femur length centiles and in placental villi with fetal OFD and subcutaneous arm fat. IGF2 expression in maternal decidua was associated with fetal BPD and in placental villi with fetal OFD.ConclusionTo our knowledge, this is the first study to demonstrate associations of imprinted genes variations at the maternal-fetal interface of the placenta and in cord blood with fetal body composition, supporting the involvement of epigenetic mechanisms in offspring growth and body composition.</p

Table_1_The relationship between obesity-related H19DMR methylation and H19 and IGF2 gene expression on offspring growth and body composition.DOCX

Background and objectiveImprinted genes are important for the offspring development. To assess the relationship between obesity-related H19DMR methylation and H19 and IGF2 gene expression and offspring growth and body composition.MethodsThirty-nine overweight/obese and 25 normal weight pregnant women were selected from the “Araraquara Cohort Study” according to their pre-pregnancy BMI. Fetal growth and body composition and newborn growth were assessed, respectively, by ultrasound and anthropometry. The methylation of H19DMR in maternal blood, cord blood, maternal decidua and placental villi tissues was evaluated by methylation-sensitive restriction endonuclease qPCR, and H19 and IGF2 expression by relative real-time PCR quantification. Multiple linear regression models explored the associations of DNA methylation and gene expression with maternal, fetal, and newborn parameters.ResultsH19DMR was less methylated in maternal blood of the overweight/obese group. There were associations of H19DMR methylation in cord blood with centiles of fetal biparietal diameter (BPD) and abdominal subcutaneous fat thickness and newborn head circumference (HC); H19DMR methylation in maternal decidua with fetal occipitofrontal diameter (OFD), HC, and length; H19DMR methylation in placental villi with fetal OFD, HC and abdominal subcutaneous fat thickness and with newborn HC. H19 expression in maternal decidua was associated with fetal BPD and femur length centiles and in placental villi with fetal OFD and subcutaneous arm fat. IGF2 expression in maternal decidua was associated with fetal BPD and in placental villi with fetal OFD.ConclusionTo our knowledge, this is the first study to demonstrate associations of imprinted genes variations at the maternal-fetal interface of the placenta and in cord blood with fetal body composition, supporting the involvement of epigenetic mechanisms in offspring growth and body composition.</p