Expressão de microRNA no plasma e suas relações com biomarcadores cardiometabólicos e dieta em idosos participantes de estudo de base populacional (ISA Capital) / Plasma microRNA expression and its associations with cardiometabolic biomarkers, and diet in elderly participants of a population-based study (ISA Capital)

Introdução - O desenvolvimento das doenças crônicas não transmissíveis (DCNT) em idosos está relacionado, dentre outros fatores, à desregulação da expressão de microRNAs (miRNAs), a qual pode ser modulada por fatores ambientais, incluindo o padrão alimentar. Objetivo - Avaliar o perfil de expressão plasmática de miRNAs e suas relações com biomarcadores cardiometabólicos e dieta em idosos do estudo de base populacional ISA Capital. Métodos - Estudo transversal, com subamostra de 200 indivíduos idosos participantes do ISA Nutrição. Foi avaliado o perfil de expressão de 21 miRNAs plasmáticos. Os indivíduos foram avaliados quanto às medidas antropométricas e à pressão arterial sistêmica; biomarcadores glicêmicos, do perfil lipídico e inflamatórios; e ao consumo alimentar. Calculou-se o escore de inflamação crônica e de baixo grau (SIS) a partir das concentrações de 10 biomarcadores inflamatórios. A expressão plasmática dos miRNAs circulantes foi analisada a partir do método Fluidigm. Os indivíduos avaliados foram distribuídos em dois grupos de acordo com a presença ou não de síndrome metabólica (SM), e o teste ajustado de Wald foi utilizado para comparar a expressão dos miRNAs entre os grupos. A partir do coeficiente tau-a de Kendall estimou-se as correlações entre a expressão dos miRNAs e variáveis de interesse. O teste de Wilcoxon-Mann-Whitney foi utilizado para determinar as diferenças no SIS em indivíduos de acordo com o sexo e a presença de SM. O teste de correlação de Spearman estimou as correlações entre o SIS, concentrações de leptina, miRNAs e demais variáveis de interesse. Além disso, utilizou-se modelos lineares generalizados (MLGs) para aprofundar as associações encontradas. As análises foram realizadas nos softwares Stata/SE (versão 17.0) e R (versão 4.2.3), considerando nível de significância de 0,05. Resultados - A amostra final deste estudo consistiu em 193 indivíduos (69,1 (0,5) anos), sendo 50,4% do sexo feminino, e 64,7% com SM. A expressão plasmática dos miR-30a e miR-122 foi maior em indivíduos com SM do que naqueles sem SM, e sua expressão se correlacionou à glicemia e insulinemia em jejum, HOMA1-IR, HDL-c, VLDL-c, LDL-c, colesterol não-HDL e triacilgliceróis. Além disso, associações negativas entre cinco miRNAs (miR-15a, miR-16, miR-223, miR-363, miR-532), concentração de leptina e/ou SIS foram observadas. Ainda, o consumo de diversos grupos alimentares influenciou a expressão plasmática dos miRNAs. O consumo diário de 100 g de frutas se relacionou à redução na expressão dos miR-16, miR-30a, miR-126, miR-130b, miR-363, miR-375, miR-486 e miR-532. Contudo, o consumo de carne vermelha se associou ao aumento na expressão plasmática de quatro miRNAs (miR-126, miR-150, miR-223 e miR-376a). Ainda, observou-se que o consumo diário de 100 g de hortaliças se associou a uma chance 7 vezes maior de os indivíduos avaliados não apresentarem SM. Conclusões - O aumento da expressão plasmática dos miR-21, miR-30a e miR-122 sugere maior risco cardiometabólico, ao passo que a redução na expressão dos miR-15a, miR-16, miR-223, miR-363 e miR-532 sugere menor risco cardiometabólico em idosos. Ainda, os resultados encontrados enfatizam a importância da adoção de hábitos alimentares saudáveis na regulação da expressão dos miRNAs e, consequentemente, na redução do risco de desenvolvimento de DCNT.

Introduction: The development of noncommunicable diseases (NCD) in older adults is related, among other factors, to the dysregulation of microRNAs (miRNAs) expression, which can be modulated by environmental factors, including dietary patterns. Objectives: To assess the plasma expression profile of miRNAs and its relationships with cardiometabolic biomarkers and diet of older adults participating in the ISA Capital population-based study. Methods: Cross-sectional study, with a sub-sample of 200 older adults participating in ISA Nutrition. The expression profile of 21 plasma miRNAs was evaluated. Subjects were evaluated for anthropometric measurements and systemic blood pressure; glycemic, lipid and inflammatory biomarkers; and food consumption. Furthermore, the chronic and low-grade inflammation score (SIS) was calculated based on the concentrations of 10 inflammatory biomarkers. The plasma expression of circulating miRNAs was analyzed using the Fluidigm method. The evaluated individuals were distributed into two groups according to the presence or absence of metabolic syndrome (MetS), and the adjusted Wald test was used to compare the expression of miRNAs between the groups. Using Kendall's tau-a coefficient, correlations between miRNAs expression and variables of interest were estimated. The Wilcoxon-Mann-Whitney test was used to determine differences in SIS based on the distribution of individuals according to sex and the presence of MetS. The Spearman correlation test estimated correlations between SIS, leptin concentrations, miRNAs and other variables of interest. Furthermore, generalized linear models were used to deepen the associations found. All analyzes were performed using Stata/SE (version 17.0) and R (version 4.2.3) software, considering a significance level of 0.05. Results: The final sample of this study consisted of 193 individuals, (69.1 (0.5) years), 50.4% of whom were female, and 64.7% with MetS. Plasma expression of miR-30a and miR-122 was higher in individuals with MetS than in those without MetS, and their expression correlated with fasting glycemia and insulinemia, HOMA1-IR, HDL-c, VLDL-c, LDL-c, non-HDL cholesterol and triacylglycerols. Furthermore, negative associations between five miRNAs (miR-15a, miR-16, miR-223, miR-363, miR-532), leptin concentration and/or SIS were observed. In addition, the consumption of different food groups influenced the plasma expression of miRNAs. Daily consumption of 100 g of fruits was related to a reduction in the expression of miR-16, miR-30a, miR-126, miR-130b, miR-363, miR-375, miR-486, miR-532. On the other hand, red meat consumption was associated with an increase in the plasma expression of four miRNAs (miR-126, miR-150, miR-223 and miR-376a). Furthermore, it was observed that the daily consumption of 100 g of vegetables was associated with a 7 times greater chance of the individuals evaluated not having MetS. Conclusions: The increase in the plasma expression of miR-21, miR-30a and miR-122 suggests a greater cardiometabolic risk, while the reduction in the expression of miR-15a, miR-16, miR-223, miR-363 and miR-532 suggests lower cardiometabolic risk in the elderly. Furthermore, the results found emphasize the importance of adopting healthy eating habits in regulating the expression of miRNAs and, consequently, in reducing the risk of developing NCD.

Circulating microrna expression profiles in patients with stable and unstable angina

OBJECTIVES: High incidence and case fatality of unstable angina (UA) is, to a large extent, a consequence of the lack of highly sensitive and specific non-invasive markers. Circulating microRNAs (miRNAs) have been widely recommended as potential biomarkers for numerous diseases. In the present study, we characterized distinctive miRNA expression profiles in patients with stable angina (SA), UA, and normal coronary arteries (NCA), and identified promising candidates for UA diagnosis. METHODS: Serum was collected from patients with SA, UA, and NCA who visited the Department of Cardiovascular Diseases of the Meizhou People's Hospital. Small RNA sequencing was carried out on an Illumina HiSeq 2500 platform. miRNA expression in different groups of patients was profiled and then confirmed based on that in an independent set of patients. Functions of differentially expressed miRNAs were predicted using gene ontology classification and Kyoto Encyclopedia of Genes and Genomes pathway analysis. RESULTS: Our results indicated that circulating miRNA expression profiles differed between SA, UA, and NCA patients. A total of 36 and 161 miRNAs were dysregulated in SA and UA patients, respectively. miRNA expression was validated by reverse transcription quantitative polymerase chain reaction. CONCLUSION: The results suggest that circulating miRNAs are potential biomarkers of UA.

Circulating exosomal micrornas as biomarkers of systemic lupus erythematosus

OBJECTIVES: Many studies indicate that microRNAs (miRNAs) could be potential biomarkers for various diseases. The purpose of this study was to investigate the clinical value of serum exosomal miRNAs in systemic lupus erythematosus (SLE). METHODS: Serum exosomes were isolated from 38 patients with SLE and 18 healthy controls (HCs). The expression of miR-21, miR-146a and miR-155 within exosomes was examined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Using receiver operating characteristic (ROC) curves, we evaluated the diagnostic value of exosomal miRNAs. RESULTS: Exosomal miR-21 and miR-155 were upregulated (p<0.01), whereas miR-146a expression (p<0.05) was downregulated in patients with SLE, compared to that in HCs. The expression of miR-21 (p<0.01) and miR-155 (p<0.05) was higher in SLE patients with lupus nephritis (LN) than in those without LN (non-LN). The analysis of ROC curves revealed that the expression of miR-21 and miR-155 showed a potential diagnostic value for LN. Furthermore, miR-21 (R=0.44, p<0.05) and miR-155 (R=0.33, p<0.05) were positively correlated with proteinuria. The expression of miR-21 was negatively associated with anti-SSA/Ro antibodies (R=−0.38, p<0.05), and that of miR-146a was negatively associated with anti-dsDNA antibodies (R=−0.39, p<0.05). CONCLUSIONS: These findings suggested that exosomal miR-21 and miR-155 expression levels may serve as potential biomarkers for the diagnosis of SLE and LN.

Expressão de microRNA circulantes em mulheres com excesso de peso suplementadas com castanha-do-brasil / 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<0,001). Foram avaliados 25 miRNA plasmáticos antes e após a intervenção. Dois miRNA (miR-454-3p e miR-584-5p) apresentaram aumento significativo (fold change maior que 2,2; P<0,05) após a ingestão de castanha-do-brasil. A análise dos seus possíveis alvos pelo software Ingenuity Pathway Analysis (IPA®, Qiagen) apontou que ambos estão relacionados com a via de ativação do VDR/RXR, podendo apresentar efeitos sobre a homeostase do cálcio, regulação do crescimento e função imune. O miR-454-3p apresentou, ainda, correlação positiva com a variação do selênio plasmático (r=0,432; P=0,005) e diversos miRNA apesentaram correlação significativa com parâmetros relacionados à síndrome metabólica e à resistência à insulina. Dessa forma, podemos concluir que o consumo da castanha-do-brasil por 60 dias é capaz de modular a expressão de miRNA circulantes em mulheres com excesso de peso, particularmente do miR-454-3p e do miR-584-5p, podendo estes serem utilizados como possíveis biomarcadores de ingestão e auxiliar, ainda, no entendimento dos mecanismos pelos quais o selênio exerce seu efeito na saúde dessa população

Excessive body weight gain accompanied by visceral fat accumulation raises the morbidity risk due to hypertension, type 2 diabetes mellitus and cardiovascular disease (CVD). Oxidative stress and inflammation play etiological role in these comorbidities. In this context, microRNAs (miRNAs) act in post-transcriptional regulation in order to maintain cellular homeostasis under physiological stress. MicroRNAs expression can be modulated by nutrients and bioactive compounds from the diet, acting on inflammatory processes, reducing the risk and/or attenuating the progression of CVD. Brazil nut is the major food source of selenium, being considered a food with potential antioxidant function to be used in patients with high cardiovascular risk. Thus, the present study aimed to evaluate the expression of circulating miRNAs in overweight and obese women before and after Brazil nuts intake. Thus, we selected 72 overweight and obese women recruited at Division of Endocrinology and Metabolism from the Clinical Hospital (School of Medicine, University of São Paulo, São Paulo, Brazil). Participants were randomly assigned to two groups: intervention group (Brazil Nut - BN group), which consumed one Brazil nut for 60 days, and control group (CO), which received no intervention during the same period. At the baseline and at the end of the intervention were performed anthropometric assessments and blood collection. The study included 54 participants: 29 from the BN group and 25 from the CO group. None of the anthropometric and biochemical variables presented significant variation between the groups during the intervention period. As expected, only the BN group showed a significant increase in plasma and erythrocyte selenium during the intervention period (> 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

Role of non-coding RNAs in non-aging-related neurological disorders

Protein coding sequences represent only 2% of the human genome. Recent advances have demonstrated that a significant portion of the genome is actively transcribed as non-coding RNA molecules. These non-coding RNAs are emerging as key players in the regulation of biological processes, and act as "fine-tuners" of gene expression. Neurological disorders are caused by a wide range of genetic mutations, epigenetic and environmental factors, and the exact pathophysiology of many of these conditions is still unknown. It is currently recognized that dysregulations in the expression of non-coding RNAs are present in many neurological disorders and may be relevant in the mechanisms leading to disease. In addition, circulating non-coding RNAs are emerging as potential biomarkers with great potential impact in clinical practice. In this review, we discuss mainly the role of microRNAs and long non-coding RNAs in several neurological disorders, such as epilepsy, Huntington disease, fragile X-associated ataxia, spinocerebellar ataxias, amyotrophic lateral sclerosis (ALS), and pain. In addition, we give information about the conditions where microRNAs have demonstrated to be potential biomarkers such as in epilepsy, pain, and ALS.