Nutritional status of zinc in children and its relation to gene expression of zinc transporters proteins ZnT1 (SLC30A1) and ZIP4 (SLC39A4)

A deficiência de zinco é considerada uma das deficiências nutricionais de maior importância epidemiológica, com grandes repercussões no contexto da saúde pública em todo o mundo. Avanços metodológicos na avaliação de aspectos moleculares constituem uma nova ferramenta para a investigação do estado nutricional dos indivíduos relativo ao zinco, por meio da avaliação da expressão gênica das proteínas transportadoras, destacando-se o ZnT1 (SLC30A1) e ZIP4 (SLC39A4), envolvidos com a manutenção da homeostase corporal do mineral. O objetivo desse trabalho foi avaliar o estado nutricional relativo ao zinco de crianças e sua relação com a expressão gênica destes transportadores. Para isso foram avaliadas 139 crianças com idade entre 32 e 76 meses matriculadas em creches da cidade de Aracaju, Sergipe. De acordo com a avaliação antropométrica, apenas 3,6% das crianças apresentaram déficit de estatura para idade e peso para idade, enquanto 27,3% delas apresentaram sobrepeso e obesidade. A deficiência de zinco plasmático foi observada em 26,6% das crianças, enquanto no eritrócito 99,3% delas encontravam-se abaixo do ponto de corte estabelecido. A análise da expressão gênica das proteínas transportadoras ZnT1 e ZIP4 apresentou relação significativa com o estado nutricional das crianças quanto ao zinco. A expressão do mRNA ZnT1 foi maior entre as crianças com deficiência, enquanto do mRNA ZIP4 foi menor. Não foram observadas relações entre o consumo de zinco e a expressão gênica. Conclui-se que a população estudada apresenta risco de deficiência em zinco, apresentando relação com a expressão gênica das proteínas transportadoras ZnT1 e ZIP4, reforçando a existência de uma regulação da absorção do mineral de acordo com o estado nutricional do indivíduo, indicando que esta análise pode ser útil na avaliação de intervenções dietéticas.Zinc deficiency is regarded as one of the nutritional deficiencies of greatest epidemiological importance, with major repercussions in the context of public health worldwide. Methodological advances in evaluation of molecular aspects constitute a new tool for investigating the zinc nutritional status of individuals, by assessing the gene expression of transporter proteins, highlighting the ZnT1 (SLC30A1) and ZIP4 (SLC39A4), involved in maintaining body homeostasis of this mineral. This study aimed to evaluate the zinc nutritional status of children and its relation to gene expression of these transporters. Were evaluated 139 children aged between 32 and 76 months attending daycare centers in the city of Aracaju, Sergipe. According to anthropometric measures, only 3.6% of children had deficit height for age and weight for age, while 27.3% of them were overweight and obese. The plasma zinc deficiency was observed in 26.6% of children, while in erythrocytes 99.3% of them were below the established cutoff point. The ZnT1 and ZIP4 gene expression analysis showed a significant relationship with the zinc nutritional status of children. The mRNA ZnT1 expression was higher among children with zinc deficiency, while mRNA ZIP4 was lower. There was no relationship between the consumption of zinc and gene expression. In conclusion, the evaluated population is at risk for zinc deficiency, showing significant relationship with the gene expression of transporter proteins ZnT1 and ZIP4, reinforcing the existence of a regulation of the absorption of the mineral according to the individual\'s nutritional status, indicating that this analysis can be useful in evaluating dietary interventions

Expression of circulating microRNAs in overweight and obese women supplemented with Brazil nut

O aumento excessivo de peso corporal acompanhado do acúmulo de gordura visceral eleva o risco de morbidade por hipertensão, diabetes mellitus tipo 2 e doença cardiovascular (DCV). O estresse oxidativo e a inflamação desempenham papel etiológico nestas comorbidades. Neste contexto, os microRNA (miRNA) atuam na regulação pós-transcricional no intuito de manter a homeostase celular sob condições de estresse fisiológico. A expressão de miRNA pode ser modulada por nutrientes e compostos bioativos provenientes da alimentação, atuando sobre processos inflamatórios, reduzindo o risco e/ou atenuando a progressão das DCV. A castanha-do-brasil é a maior fonte alimentar de selênio, sendo considerada um alimento com potencial função antioxidante podendo ser utilizado em pacientes com elevado risco cardiovascular. Dessa forma, o objetivo do presente estudo foi avaliar a expressão de microRNA circulantes em mulheres com excesso de peso antes e após o consumo da castanha-do-brasil. Para isso, foram selecionadas 72 mulheres com excesso de peso que frequentam o serviço de endocrinologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP). As participantes foram distribuídas aleatoriamente em dois grupos: grupo intervenção (grupo Brazil Nut - BN), que consumiu uma unidade de castanha-do-brasil durante 60 dias, e grupo controle (CO), que não recebeu intervenção durante o mesmo período. Ao início e ao final da intervenção foram realizadas avaliações antropométricas e coleta de sangue. Foram incluídas no estudo 54 participantes: 29 do grupo BN e 25 do grupo CO. Nenhuma das variáveis antropométricas e bioquímicas apresentou variação significativa entre os grupos durante o período de intervenção. Conforme esperado, apenas o grupo BN apresentou um aumento significativo do selênio plasmático e eritrocitário durante o período de intervenção (> 200%; P 200%; P<0.001). We evaluated 25 circulating miRNAs before and after the intervention. Two miRNAs (miR-454-3p and miR-584-5p) presented a significant increase (fold change greater than 2.2; P <0.05) after Brazil nuts intake. The analysis of potential targets by the Ingenuity Pathway Analysis software (IPA®, Qiagen) indicated that both are related to the VDR/RXR activation pathway, and may have effects on calcium homeostasis, growth regulation and immune function. Furthermore, miR-454-3p presented a positive correlation with plasma selenium (r = 0.432, P = 0.005) and several miRNAs showed a significant correlation with parameters related to metabolic syndrome and insulin resistance. Thus, we conclude that Brazil nut inatke for 60 days is capable of modulating circulating miRNAs in overweight and obese women, particularly miR-454-3p and miR-584-5p, and these may be used as possible biomarkers of intake and help to understand the mechanisms by which selenium exerts its effect on health of this population

Consumption of Brazil nuts with high selenium levels increased inflammation biomarkers in obese women: A randomized controlled trial

Objective: Increased inflammatory response is an important factor in the pathophysiology of obesity. The mineral selenium (Se), of which one of the main food sources is the Brazil nut, has important antioxidant and anti-inflammatory functions through the action of selenoproteins. Thus, the evaluation of the influence of this micronutrient in this context is of great relevance. The aim of this study was to evaluate the effects of Brazil nut intake with high Se concentrations on inflammatory biomarkers and its relation to Se status in obese women. Methods: A randomized controlled clinical trial was carried out with 55 women recruited at Clinical Hospital in Sao Paulo, Brazil. Patients were randomly assigned to either the Brazil nut group (BN) or the control group ~ (CO) and followed up for 2 mo. The BN group consumed 1 unit/d of Brazil nuts (» 1261 mg/Se); the CO group did not receive any intervention. At baseline and after 2 mo, analysis of biochemical parameters related to Se status, oxidative stress, and inflammatory biomarkers were performed. Results: At baseline, both groups did not present Se deficiency. In the BN group, a significant increase (P < 0.05) in all Se biomarkers and in gene expression of several proinflammatory parameters (interleukin-6, tumor necrosis factor-a, and Toll-like receptors 2 and 4) were observed after the intervention period. No changes were observed for the CO group. Conclusion: Although there were no changes in plasma inflammatory biomarkers levels, a significant increase in gene expression may be an indication of a proinflammatory stimulus in obesity, induced by the consump- tion of Brazil nuts with high Se levels.UCR::Vicerrectoría de Docencia::Salud::Facultad de Medicin

Brazil nut intake increases circulating miR-454-3p and miR-584-5p in obese women

Artículo realizando durante un postgrado en el extranjero para obtener el título de doctorado en la Universidad de São Paulo, BrasilThe Brazil nut is an excellent source of selenium (Se), an essential micronutrient for human health. In this study, we hypothesized that Brazil nut intake modulates circulating microRNAs (miRNAs) in obese women and aimed to evaluate the effects of this nut intake on circulating miRNAs in women with obesity or metabolic syndrome (MetS). A randomized controlled clinical trial was conducted on 54 subjects recruited from the Clinical Hospital in São Paulo, Brazil. Patients were randomly assigned to 2 groups: a Brazil nut group (BN group, n = 29) and a control group (CO group, n = 25); both were monitored for 2 months. BN group members were instructed to consume 1 Brazil nut (approximately 1261 μg/Se) per day; CO group members were instructed not to consume any. Biochemical parameters related to Se status and 25 circulating miRNAs in plasma were evaluated in all patients both at baseline and after 2 months. Expression levels of 2 miRNAs (miR-454-3p and miR-584-5p) were significantly increased after Brazil nut intake. To investigate the effect of MetS on circulating miRNAs at baseline, we performed comparisons between women with MetS (n = 23) and women without MetS (others, n = 31). Circulating miR-375 levels were significantly lower (P = .012) in women with MetS. In conclusion, our findings suggested that a daily intake of 1 Brazil nut increased circulating miR-454-3p and miR-584-5p expression levels in obese women, and our network analysis indicated a link between Se intake, vitamin D metabolism, and calcium homeostasis.UCR::Vicerrectoría de Docencia::Salud::Facultad de Medicina::Escuela de MedicinaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP