Dietary modulation of microRNAs in insulin resistance and type 2 diabetes.

The prevalence of type 2 diabetes is increasing worldwide. Various molecular mechanisms have been proposed to interfere with the insulin signaling pathway. Recent advances in proteomics and genomics indicate that one such mechanism involves the post-transcriptional regulation of insulin signaling by microRNA (miRNA). These noncoding RNAs typically induce messenger RNA (mRNA) degradation or translational repression by interacting with the 3' untranslated region (3'UTR) of target mRNA. Dietary components and patterns, which can either enhance or impair the insulin signaling pathway, have been found to regulate miRNA expression in both in vitro and in vivo studies. This review provides an overview of the current knowledge of how dietary components influence the expression of miRNAs related to the control of the insulin signaling pathway and discusses the potential application of these findings in precision nutrition.

Blood orange juice intake changes specific bacteria of gut microbiota associated with cardiometabolic biomarkers.

Blood orange juice is an important source of flavanones and anthocyanins, mainly hesperidin, narirutin, and cyanidin-3-O-glucoside. The benefits of these bioactive compounds have been reported, but the mechanistic details behind their biological effects are not well established. This study investigated the effects of Moro orange (Citrus sinensis L. Osbeck) juice (MOJ) on gut microbiota composition and cardiometabolic biomarkers in overweight women. In this study, 12 overweight women (BMI from 25.0 to 29.9 kg/m2), aged 18-37 years, consumed 500 mL of MOJ every day for 4 weeks. We assessed the gut microbiota composition, levels of short-chain fatty acids (SCFAs), cardiometabolic biomarkers, and insulin resistance (HOMA-IR) at baseline and after 2 weeks and 4 weeks of MOJ intake. The results suggested that MOJ intake affected the abundance of specific operational taxonomic units (OTUs) of the gut microbiota but did not significantly alter the diversity and general composition of the gut microbiota. However, MOJ intake increased the production of SCFAs, especially propionic and isobutyric acids, and significantly improved cardiometabolic biomarkers such as blood pressure and plasma VCAM-1 levels in the overweight women. Additionally, we observed significant associations between gut microbiota OTUs belonging to the Bacteroidetes phyla and Prevotella 9 genera and the cardiometabolic biomarkers. Furthermore, MOJ reduced fasting glucose and insulin levels and HOMA-IR values, thereby enhancing insulin sensitivity in the insulin-resistant overweight women. Finally, we highlighted the importance of orange juice intake duration because some beneficial changes such as blood pressure improvements were evident at the 2-week time interval of the intervention, but other changes became significant only at the 4-week interval of MOJ intake. In conclusion, our study demonstrated that changes in specific OTUs of the gut microbiota in response to MOJ intake were associated with significant improvements in some cardiometabolic biomarkers and SCFA levels in overweight women with insulin resistance.

Efeito da ingestão de suco de uva sobre a expressão de microRNA no plasma e em células mononucleares em mulheres com sobrepeso / Effect of grape juice ingestion on microRNA expression in plasma and mononuclear cells in overweight women

Introdução: O padrão da dieta ocidental, caracterizado pela ingestão elevada de açúcares e lipídios, está relacionado à gênese da inflamação metabólica, a qual é caracterizada por um quadro de inflamação crônica, sistêmica e de baixa intensidade. A inflamação metabólica contribui para o desenvolvimento de doenças crônicas não transmissíveis (DCNT), as quais representam a principal causa de morte no mundo. Por outro lado, a ingestão de uma dieta saudável, rica em frutas e hortaliças, é relevante para a redução do risco das DCNT. Nesse contexto, destaca-se o suco de uva, bebida rica em compostos bioativos, que possui potencial efeito anti-inflamatório. Estudos recentes sugerem que nutrientes e compostos bioativos dos alimentos possam atenuar a inflamação por meio da modulação da expressão de microRNA, os quais representam novos biomarcadores inflamatórios, contribuindo para a identificação do risco de desenvolvimento de doenças cardiometabólicas. Objetivo: Investigar o efeito da ingestão de suco de uva integral sobre a expressão de microRNA no plasma e em células mononucleares do sangue periférico (PBMC) e sua relação com a resposta inflamatória. Métodos: Estudo intervencional, no qual, durante quatro semanas, as voluntárias ingeriram 500 mL diários de suco de uva integral, com coletas de sangue no momento basal, 2 e 4 semanas após o início da ingestão da bebida. A população do estudo foi composta por mulheres saudáveis (n = 20), com idade entre 18 e 40 anos e índice de massa corpórea classificado como sobrepeso (25,0 - 29,9 kg/m2). Foram avaliados o perfil lipídico, o hemograma e as concentrações plasmáticas de glicose, insulina, leptina, adiponectina, lipopolissacarídeos e seus ligantes plasmáticos LBP e sCD14 e biomarcadores inflamatórios (IL-10, IL-6, TNF-α, proteína C reativa, MCP-1, VCAM-1 e ICAM-1), bem como a concentração dos principais compostos bioativos presentes no suco de uva. Dois painéis de microRNA, sendo um plasmático e outro de PBMC, de 8 indivíduos foram avaliados, em todos os tempos, pelo ensaio de PCR em tempo real. Posteriormente, foram selecionados os microRNA relacionados à resposta inflamatória e à endotoxemia metabólica, os quais foram avaliados no restante das voluntárias. As proteínas-alvo dos microRNA em PBMC foram analisadas por Western Blotting. O consumo alimentar foi avaliado pela análise de três recordatórios de 24 horas coletados em todos os tempos experimentais. Resultados: A ingestão de suco de uva, após 4 semanas de intervenção, em PBMC, promoveu redução da expressão gênica do TNF-α, IL-6 e das subunidades p50 e p65, as quais compõem o fator de transcrição NF-kB. Em relação ao conteúdo de proteínas nestas células, houve apenas diminuição da fosforilação da TAK-1 em relação ao seu conteúdo total. Dentre os miRNA analisados, o miR-144-5p e o miR-144-3p tiveram a sua expressão aumentada no plasma e em PBMC, respectivamente. A concentração plasmática de sICAM-1 reduziu significativamente na semana 4 em relação a semana 2, enquanto, a concentração plasmática de gama glutamil transferase aumentou significativamente na última semana. As voluntárias apresentaram menor pressão arterial diastólica no final do estudo em relação ao momento basal. Conclusão: A ingestão do suco de uva, após 4 semanas de intervenção, influenciou a concentração de biomarcadores relacionados ao processo inflamatório mediado pela via do fator de transcrição NF-kB em mulheres com sobrepeso.

Introduction: The Western diet pattern, characterized by excessive ingestion of sugars and lipids, is related to the genesis of metabolic inflammation, which is characterized by a condition of a chronic, systemic, and low-grade inflammation. Metabolic inflammation contributes to the development of chronic non-communicable diseases (NCDs), the leading cause of death in the world. On the other hand, the adoption of a healthy diet rich in fruits and vegetables is relevant to reduce the risk of NCDs. Grape juice is a beverage rich in bioactive compounds which have a potential anti-inflammatory effect. Recent studies suggest that nutrients can modulate inflammation through microRNAs action, which have been highlighted because they are new inflammatory biomarkers, contributing to the identification of the risk of cardiometabolics diseases. Objective: Investigate the effect of the grape juice ingestion on microRNA expression in plasma and peripheral blood mononuclear cells (PBMC) and its relationship with the development of the inflammatory process. Methods: Interventional study, in which, for four weeks, the volunteers ingested 500 mL of whole grape juice daily, with blood drawn at baseline, 2 and 4 weeks after the intake. The study population consisted of healthy women (n = 20), aged between 18 and 40 years and body mass index classified as overweight (25.0 - 29.9 kg/m2). The lipid profile, blood count and plasma concentrations of glucose, insulin, leptin, adiponectin, lipopolysaccharides, and their plasma ligands LBP and sCD14 and inflammatory biomarkers (IL-10, IL-6, TNF-α, C-reactive protein, MCP-1, VCAM-1 and ICAM-1) were evaluated, as well as the concentration of the main bioactive compounds present in grape juice. Two microRNA panels, one plasma and the other PBMC, from 8 individuals were evaluated, at all times, by real-time PCR. Subsequently, microRNAs related to the inflammatory response and metabolic endotoxemia were selected, which were evaluated in the rest of the volunteers. MicroRNA target proteins in PBMC were analyzed by Western Blotting. Food consumption was assessed by analyzing three 24-hour recalls collected at all experimental times. Results: The intake of grape juice, after 4 weeks of intervention, in PBMC, promoted a reduction in gene expression of TNF-α, IL-6 and p50 and p65 subunits, which composes the NF-kB transcription factor. Regarding the protein content in these cells, there was only a decrease in TAK-1 phosphorylation in relation to its total content. Among the analyzed miRNAs, miR-144-5p and miR-144-3p had their expression increased in plasma and in PBMC, respectively. The plasma concentration of sICAM-1 significantly reduced in week 4 compared to week 2, while the plasma concentration of gamma glutamyl transferase increased significantly in the last week. The volunteers had lower diastolic blood pressure at the end of the study compared to baseline. Conclusion: The intake of grape juice after 4 weeks of intervention influenced the concentration of biomarkers related to the inflammatory process mediated by the transcription factor NF-kB pathway in overweight women.

Postprandial plasma lipidome responses to a high-fat meal among healthy women.

Postprandial lipemia consists of changes in concentrations and composition of plasma lipids after food intake, commonly presented as increased levels of triglyceride-rich lipoproteins. Postprandial hypertriglyceridemia may also affect high-density lipoprotein (HDL) structure and function, resulting in a net decrease in HDL concentrations. Elevated triglycerides (TG) and reduced HDL levels have been positively associated with risk of cardiovascular diseases development. Here, we investigated the plasma lipidome composition of 12 clinically healthy, nonobese and young women in response to an acute high-caloric (1135 kcal) and high-fat (64 g) breakfast meal. For this purpose, we employed a detailed untargeted mass spectrometry-based lipidomic approach and data was obtained at four sampling points: fasting and 1, 3 and 5 h postprandial. Analysis of variance revealed 73 significantly altered lipid species between all sampling points. Nonetheless, two divergent subgroups have emerged at 5 h postprandial as a function of differential plasma lipidome responses, and were thereby designated slow and fast TG metabolizers. Late responses by slow TG metabolizers were associated with increased concentrations of several species of TG and phosphatidylinositol (PI). Lipidomic analysis of lipoprotein fractions at 5 h postprandial revealed higher TG and PI concentrations in HDL from slow relative to fast TG metabolizers, but not in apoB-containing fraction. These data indicate that modulations in HDL lipidome during prolonged postprandial lipemia may potentially impact HDL functions. A comprehensive characterization of plasma lipidome responses to acute metabolic challenges may contribute to a better understanding of diet/lifestyle regulation in the metabolism of lipid and glucose.

Nutritional genomics, inflammation and obesity.

The Human Genome Project has significantly broadened our understanding of the molecular aspects regulating the homeostasis and the pathophysiology of different clinical conditions. Consequently, the field of nutrition has been strongly influenced by such improvements in knowledge - especially for determining how nutrients act at the molecular level in different conditions, such as obesity, type 2 diabetes, cardiovascular disease, and cancer. In this manner, characterizing how the genome influences the diet and vice-versa provides insights about the molecular mechanisms involved in chronic inflammation-related diseases. Therefore, the present review aims to discuss the potential application of Nutritional Genomics to modulate obesity-related inflammatory responses. Arch Endocrinol Metab. 2020;64(3):205-22.

Circulating plasma microRNAs dysregulation and metabolic endotoxemia induced by a high-fat high-saturated diet.

High-fat diet increase two to three times the plasma lipopolysaccharide (LPS) levels and induce subclinical inflammation. Diet can modify gene expression due to epigenetic processes related to MicroRNAs (miRNAs). MicroRNAs (miRNAs) play important role in the post-transcriptional mechanisms involved in regulation of expression of genes related to the inflammatory response. Also, diet can indirectly induce post-transcriptional regulation of gene expression by miRNAs, which may affect the risk for the development of chronic diseases. OBJECTIVE: This study investigated the effect of high-fat high-saturated meal ingestion on plasma miRNA expression and LPS levels during the postprandial period in healthy women. METHODS: An interventional study was carried out in which a high-fat breakfast (1067.45 kcal), composed mainly of saturated fatty acids (56 g), and 500 mL of water, was offered. Blood samples were collected at baseline and 1, 3 and 5 h after meal intake. The studied population consisted of healthy women (n = 11), aged between 20 and 40 years, and body mass index (BMI) between 18.5 and 25 kg/m2. Plasma levels of lipid profile, cytokines, adhesion molecules, and LPS were measured at the 3 time points. A profile of 752 human plasma miRNA expression was analyzed by real-time PCR assay. These analyzes were performed for all blood collection time-points. RESULTS: Expression profile analysis revealed 33 differentially expressed plasma circulating miRNAs compared to that of the control group. MiR-145-5p and miR-200 were differentially modulated in all time-points post meal consumption. In addition, there was a significant increase in plasma LPS, triglycerides, myristic and palmitic saturated fatty acids levels at the 3 time-points in comparison with the control basal levels. We also observed increased levels of the plasma tumor necrosis factor alpha (TNF-α) cytokine and the vascular cell adhesion molecule 1 (VCAM-1) levels after 5 h post meal ingestion. CONCLUSION: Ingestion of high-fat high-saturated meal was able to induce metabolic endotoxemia and increase the expression of pro-inflammatory molecules such as TNF-alpha and VCAM-1, as well as modulating circulating miRNAs possibly controlling inflammatory and lipid metabolism proteins at the postprandial period.

Efeito de uma refeição hiperlipídica no período pós-prandial sobre a expressão de microRNA em mulheres saudáveis / Effect of a high-fat meal in the postprandial period on microRNA expression in health women

Introdução - Evidências mostram que a ingestão de uma refeição hipercalórica, rica em lipídios e açúcares, provoca elevação da concentração plasmática de glicose e de triacilgliceróis (TG), bem como de lipopolissacarídeos (LPS) no período pós-prandial. Sugere-se que essa condição esteja envolvida na gênese da inflamação subclínica, caracterizada pelo aumento da concentração de biomarcadores pró-inflamatórios na circulação sanguínea, como o fator de necrose tumoral (TNF)-α, interleucina (IL)-1β, IL- 6 e as moléculas de adesão intracelular solúvel (sICAM)-1 e vascular solúvel (sVCAM)- 1, o que contribui para o aumento do risco para doenças cardiovasculares. Estudos recentes sugerem que os microRNA (miRNA) atuam como biomarcadores inflamatórios e a análise da sua expressão no período pós-prandial pode contribuir para a redução do risco de doenças cardiovasculares. Objetivo - Investigar o efeito de uma refeição hiperlipídica, rica em ácidos graxos saturados, sobre a expressão de microRNA e a concentração de LPS no plasma no período pós-prandial em mulheres saudáveis. Métodos - Realizou-se um estudo de intervenção no qual foi oferecido uma refeição matinal com alto teor de lipídios, principalmente, de ácidos graxos saturados, mais 500 mL de água, realizando-se coletas de sangue no período basal e 1, 3 e 5 horas após a ingestão da refeição hiperlipídica. A população do estudo foi composta por mulheres saudáveis (n = 11), com idade entre 20 e 40 anos, e IMC de 18,5 a 25 kg/m². Foram avaliadas as concentrações plasmáticas de glicose, insulina, perfil lipídico e de ácidos graxos, citocinas, moléculas de adesão, MCP-1 e LPS. Analisou-se pelo ensaio de PCR em tempo real, um perfil de expressão de 752 miRNA plasmáticos humanos. Essas análises foram realizadas em todos os tempos da coleta de sangue. Resultados - Houve aumento significativo das concentrações plasmáticas de LPS e TG nos tempos 1, 3 e 5 horas em relação ao período basal. As concentrações plasmáticas de insulina elevaram-se de forma significativa após 1 e 3 horas em comparação ao período basal, e reduziu após 5 h se comparado ao tempo 1 h. Os ácidos graxos saturados plasmáticos mirístico e palmítico aumentaram após o consumo da refeição. Houve aumento das concentrações plasmáticas de TNF-α após 5h se comparado ao basal e ao tempo 1 h. E houve aumento da concentração de sVCAM-1 após 5 h vs o basal. Em relação aos miRNA, 45 miRNA tiveram suas concentrações alteradas se comparadas entre todos os tempos, destes 33 miRNA vs o basal. Conclusões - O aumento de TG e insulina após a refeição hiperlipídica pode contribuir para explicar a participação da dieta no desenvolvimento de um quadro inflamatório, promovido, também, por um quadro de endotoxemia pós-prandial. Junto a isso, os miRNA podem exercer papel importante na regulação deste quadro. Uma refeição hiperlipídica, com elevado teor de ácidos graxos saturados, ocasiona um quadro de endotoxemia metabólica e altera a expressão de microRNA plasmáticos envolvidos na regulação do processo inflamatório no período pós-prandial

Introduction Evidence shows that a high caloric meal, rich in lipids and carbohydrates, increase glucose and triacyclglycerols (TG) concentrations, furthermore in lipopolysaccharides (LPS) in the postprandial period. This condition is involved with subclinic inflammation genesis, characterized by increased concentration of inflammatory biomarkers in blood circulation, like tumor necrose fator (TNF)-α, interleukin (IL)-1β, IL-6 and soluble intracellular adhesion molecule (sICAM)-1 and soluble vascular (sVCAM)-1, what contributes to rise cardiovascular disease risk. Recent studies indicate that microRNAs (miRNA) act as inflammatory biomarkers and analysis of their expression in the postprandial state could contribute to reduction of cardiovascular disease risk. Objective This study investigates the high-fat high-saturated meal effect above miRNA expression and LPS concentration at the postprandial period in healthy women. Methods An interventional study was carried out in which a breakfast with a high lipid content, mainly of saturated fatty acids, plus 500 mL of water was offered. Blood samples were collected at baseline and 1, 3 and 5 hours after ingestion of the high-fat meal. The study population consisted of healthy women (n = 11), aged between 20 and 40 years, and BMI of 18.5 to 25 kg / m². Plasma concentrations of glucose, insulin, lipid profile and fatty acids, cytokines, adhesion molecules, MCP-1 and LPS were evaluated. An expression profile of 752 human plasma miRNA was analyzed by the real-time PCR assay. These analyzes were performed at all times of blood collection. Results - There was a significant increase in the plasma concentrations of LPS and TG at times 1, 3, 5 hours in relation to the baseline. Plasma insulin concentrations increased significantly after 1 and 3 hours compared to baseline, and decreased after 5 h compared to 1 h. Myristic and palmitic saturated fatty acids increased after consumption of the meal. There was an increase in plasma concentrations of TNF-α after 5 hours compared to the baseline and at 1 h. And there was an increase in sVCAM-1 concentration after 5 hours vs baseline. Regarding the miRNA, 45 miRNA had their concentrations altered when compared among all the times, of these 33 miRNA vs the baseline. Conclusions - The increase of TG and insulin after the high-fat meal may contribute to explain diet participation in the development of an inflammatory condition, also promoted by postprandial endotoxemia. In addition, microRNAs may play a key role in the regulation of this condition. High-fat high-saturated meal generates a metabolic endotoxemia state and changes plasma microRNAs expression which are involved in regulation to inflammatory process in the postprandial period