1.
Inter-Individual Variability in Insulin Response after Grape Pomace Supplementation in Subjects at High Cardiometabolic Risk: Role of Microbiota and miRNA.
Ramos-Romero, S, Léniz, A, Martínez-Maqueda, D, Amézqueta, S, Fernández-Quintela, A, Hereu, M, Torres, JL, Portillo, MP, Pérez-Jiménez, J
Molecular nutrition & food research. 2021;(2):e2000113
Abstract
SCOPE Dietary polyphenols have shown promising effects in mechanistic and preclinical studies on the regulation of cardiometabolic alterations. Nevertheless, clinical trials have provided contradictory results, with high inter-individual variability. This study explores the role of gut microbiota and microRNAs (miRNAs) as factors contributing to the inter-individual variability in polyphenol response. METHODS AND RESULTS 49 subjects with at least two factors of metabolic syndrome are divided between responders (n = 23) or non-responders (n = 26), depending on the variation rate in fasting insulin after grape pomace supplementation (6 weeks). The populations of selected fecal bacteria are estimated from fecal deoxyribonucleic acid (DNA) by quantitative real-time polymerase chain reaction (qPCR), while the microbial-derived short-chain fatty acids (SCFAs) are measured in fecal samples by gas chromatography. MicroRNAs are analyzed on a representative sample, followed by targeted miRNA analysis. Responder subjects show significantly lower (p < 0.05) Prevotella and Firmicutes levels, and increased (p < 0.05) miR-222 levels. CONCLUSION After evaluating the selected substrates for Prevotella and target genes of miR-222, these variations suggest that responders are those subjects exhibiting impaired glycaemic control. This study shows that fecal microbiota and miRNA expression may be related to inter-individual variability in clinical trials with polyphenols.
2.
Levels of Circulating miR-122 are Associated with Weight Loss and Metabolic Syndrome.
Hess, AL, Larsen, LH, Udesen, PB, Sanz, Y, Larsen, TM, Dalgaard, LT
Obesity (Silver Spring, Md.). 2020;(3):493-501
Abstract
OBJECTIVE This study investigated whether the levels of specific serum microRNAs (miRNAs) were altered following diet-induced weight loss and whether the serum miRNAs differed in the presence of the metabolic syndrome. METHODS The study was a weight loss intervention trial with a prescribed energy deficit of approximately 500 kcal/d. Levels of 22 miRNAs were determined in serum samples from 85 participants with overweight or obesity. miRNAs were analyzed using TaqMan Array miRNA Cards and normalized to the geometric mean of spiked-in ath-miR-159a and U6 small nuclear RNA using the ΔCT method. RESULTS The average weight loss was 5.7 kg (P < 0.001). miR-122-5p (-0.18 ± 0.06 log fold relative to initial, P < 0.01) and miR-193a-5p (-0.12 ± 0.04, P < 0.01) levels decreased in response to weight loss. miR-126a-3p (0.11 ± 0.04, P = 0.01) and miR-222-3p (1.51 ± 0.12, P < 0.001) levels increased. Furthermore, a higher level of miR-122-5p was observed at baseline in participants with the metabolic syndrome compared with participants without (0.28 ± 0.08, P < 0.01). CONCLUSIONS Changes in circulating miR-122-5p, miR-126a-3p, miR-193a-5p, and miR-222-3p in response to diet-induced weight loss are demonstrated. Furthermore, assessment of miR-122-5p could be an indicator of an adverse metabolic health status independent of obesity.
3.
Brazil nut intake increases circulating miR-454-3p and miR-584-5p in obese women.
Reis, BZ, Duarte, GBS, Vargas-Mendez, E, Ferreira, LRP, Barbosa, F, Cercato, C, Rogero, MM, Cozzolino, SMF
Nutrition research (New York, N.Y.). 2019;:40-52
Abstract
The 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.