Higher expression of miR-15b-5p with inclusion of fresh, lean beef as part of a healthy dietary pattern is inversely associated with markers of cardio-metabolic disease risk

Background Considerable controversy exists surrounding the consumption of red meat and its impacts on cardio-metabolic health and may further impact risk factors at the molecular level. Objective The purpose of this study was to examine the acute effects of dietary patterns, varying in red meat quantity, on the expression of circulating microRNA (miRNA)s, which are emerging biomarkers of metabolic dysfunction and chronic disease severity. Methods Secondary analyses were performed from plasma samples collected within a randomized, crossover design study in 16 women with overweight (mean ± SD, age = 33 ± 9.89y; BMI = 27.9 ± 1.66kg/m2). Participants were provided with eucaloric, isonitrogenous diets (15% of daily intake as protein) containing either 2 servings of fresh, lean beef/d (BEEF) or 0 servings of fresh, lean beef/d (PLANT) for 7 days/pattern. Fasting blood samples were collected at the end of each dietary pattern for the assessment of 12 a priori circulating metabolic miRNA expression levels (RT-qPCR), plasma glucose, insulin, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), adiponectin, glucagon-like peptide-1 (GLP-1) and branched-chain amino acids (BCAA). Results Of the 12 miRNAs, miR-15b-5p expression was higher following BEEF vs. PLANT (P=0.024). Increased miR-15b-5p expression correlated with decreased fasting CRP (r=-0.494; P=0.086) and insulin concentrations (r=-0.670; P=0.017). miR-15b-5p was inversely correlated with insulin resistance (r= -0.642; P=0.024) and beta cell function (r=-0.646; P=0.023), and positively correlated with markers of insulin sensitivity (r=0.520; P=0.083). However, the correlations were only observed following BEEF, not PLANT. Conclusions These data indicate that the short-term intake of fresh, lean beef as part of a healthy dietary pattern impacts potential biomarkers of cardiometabolic health which are associated with cardiometabolic risk factors in women with overweight. Clinical Trials Number NCT02614729