Blood Orange Juice Intake Modulates the Expression of miR-126–3p and let-7f-5p in PBMC of Overweight and Insulin Resistance Women

Abstract Objectives To investigate the effect of chronic blood orange juice intake on the microRNA profile in peripheral blood mononuclear cells (PBMC) of overweight and insulin resistance women. Methods Interventional and chronic study with women (n = 8) aged 18 to 40 years, diagnosed with overweight [body mass index (BMI) 25–29.9 kg/m2] and insulin resistance [homeostatic model assessment insulin resistance (HOMA-IR) index >2,71]. For four weeks, the volunteers ingested 500 mL/day of blood orange juice (Moro variety), with blood samples collected at baseline and four weeks after the beginning of drink ingestion. Evaluation of the expression of 137 microRNAs in PBMC was performed by real-time polymerase chain reaction (PCR). Results Blood orange juice intake decreased the expression of miR-126-3p (p = 0.004) and let-7f-5p (p = 0.005) in PBMC. These microRNAs are involved in suppressing the synthesis of several proteins of the insulin signaling pathway. Insulin receptor substrates (IRS) 1 and 2 were identified as target genes of mir-126. Insulin-like growth factor 1 receptor (IGF1R), insulin receptor (INSR), IRS2, phosphatidylinositol-3-kinase interacting protein 1 (PIK3IP1), and protein kinase B/Akt 2 (AKT2) were identified as target genes of let-7f. Conclusions Blood orange juice, rich in vitamin C, flavonoids, and anthocyanins, downregulates the expression of microRNA involved in impairing the insulin signaling pathway. Funding Sources Food Research Center (FoRC), São Paulo Research Foundation (FAPESP)