Search

Objective This study aimed to investigate cellular sources of microRNAs (miRNA) within adipose tissue and the impact of obesity on miRNA expression, as well as to examine targets of miRNAs. Methods miRNA expression by quantitative polymerase chain reaction was examined in adipocytes, adipose tissue macrophages (ATM), and peripheral blood mononuclear cells from and individuals with normal weight and with obesity. Differentiated 3T3-L1 adipocytes were cocultured with macrophages, and 3T3-L1 and differentiated human mesenchymal stem cells were transfected with miR-155, with peroxisome proliferator-activated receptor gamma (PPAR-γ) and solute carrier family 2 member 4 (GLUT4) abundance measured via Western blot analysis. Results Abundance of miR-155 and miR-210 was increased in ATM of participants with obesity by 6.7-fold and 2.9-fold (P = 0.002 and P = 0.013, respectively). miR-130b expression was increased 1.8-fold in ATM and 4.3-fold in adipocytes from participants with obesity (P = 0.007 and P = 0.02, respectively). PPARG mRNA expression decreased 32% (P = 0.044) in adipocytes from individuals with obesity. In 3T3-L1 cells exposed to macrophages, PPARG expression decreased 99.4% (P = 0.02). PPAR-γ protein content declined 75% (P = 0.001) in 3T3-L1 cells transfected with miR-155. GLUT4 protein levels were reduced by 55% (P = 0.021) in differentiated human mesenchymal stem cells exposed to miR-155. Conclusions Adipose tissue miRNAs are influenced in a cell type-specific fashion by obesity, with macrophage miR-155 potentially impacting neighboring adipocytes.

Objective The goal of this study was to examine the associations of maternal weight status before, during, and after pregnancy with breast milk C-reactive protein (CRP) and interleukin 6 (IL-6), two bioactive markers of inflammation, measured at 1 and 3 months post partum. Methods Participants were 134 exclusively breastfeeding mother-infant dyads taking part in the Mothers and Infants Linked for Health (MILK) study, who provided breast milk samples. Pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) were assessed by chart abstraction; postpartum weight loss was measured at the 1- and 3-month study visits. Linear regression was used to examine the associations of maternal weight status with repeated measures of breast milk CRP and IL-6 at 1 and 3 months, after adjustment for potential confounders. Results Pre-pregnancy BMI and excessive GWG, but not total GWG or postpartum weight loss, were independently associated with breast milk CRP after adjustment (β = 0.49, P

SummaryBackground Much is to be learnt about human breast milk (HBM). Objectives The purpose of this study is to extend our knowledge of HBM by investigating the role of maternal body mass index (BMI), sex and stage of lactation (month 1 vs. 6) on HBM insulin, glucose, leptin, IL-6 and TNF-α and their associations with infant body composition. Methods Thirty-seven exclusively breastfeeding infants (n = 37; 16♀, 21♂), and their mothers (19–47 kg m−2) were studied at 1 and 6 months of lactation. Infants had body composition measured (using dual-energy X-ray absorptiometry) and HBM collected. Results A significant interaction between maternal BMI and infant sex on insulin levels (p = 0.0322) was observed such that insulin was 229% higher in obese mothers nursing female infants than in normal weight mothers nursing female infants and 179% higher than obese mothers nursing male infants. For leptin, a significant association with BMI category was observed (p

SummaryBackground Detailed measures of infant body composition are needed for understanding the impact of genes and environment on growth early in life. Objective The purpose of this study was to compare the accuracy and bias of body composition in infants. Methods Dual energy X-ray absorptiometry (DXA) and magnetic resonance imaging (MRI) were used to determine body composition and the trunk depot. The depots measured were total fat mass (FM), total fat-free mass (FFM) and trunk FM and FFM using DXA and MRI in 14 infants. Results None of the regression lines between DXA and MRI significantly deviate from the line of identity for any of the depots studied. However, Bland–Altman analyses revealed bias for trunk FM and trunk FFM. Conclusion Our data showed DXA to be accurate (regression not significantly deviating from the line of identity), with high agreement (indicated by high R2) and without bias (non-significant Bland–Altman) when estimating total FM and FFM. This could not be said for trunk estimates.

Taurine has been demonstrated to be conditionally indispensable for several carnivorous fish species. Current trends in trout production include decreasing levels of fish-meal content in feeds, along with faster growing strains of fish. Taurine may be a limiting nutrient in support of elevated planes of growth for rainbow trout. A 9-wk feeding trial was conducted using a factorial treat- ment design with protein source (fish meal or plant) and taurine supplementation (four levels) as the main effects. The fish-meal diet series included 23% herring meal and contained 1.76% total sulfur amino acids (TSAA). The plant diet series did not contain any animal proteins and substituted protein from soy protein concentrate in place of the herring-meal protein and contained 1.5% TSAA. Taurine was supplemented at 0, 5, 10, and 15 g/kg dry diet to each of the diets in the plant series and the fish-meal series of diets. All diets were formulated to contain 43.8% crude protein and 20% lipid with an estimated physiological fuel value of 4.2 kcal/g. Fifteen fish were stocked in each of 24 tanks with a mean initial weight of approximately 26.8 g per fish. The un- supplemented fish-meal diet contained 2 g/kg tau- rine, and the unsupplemented plant diet had taurine levels below the detection limit of 0.1 g/kg diet. Taurine supplementation improved growth, feed conversion ratios, protein retention efficiencies, and energy retention efficiencies of fish fed the plant protein diets. No effects of taurine supplementation were observed for these response factors in fish fed the fish-meal series diets. This study demonstrates that taurine supplementation may be necessary for rainbow trout fed plant-protein- based feeds. The removal offishmeal from the diet of rain- bow trout and other carnivorous fish species has had wide interest globally. Current diet formula- tions often utilize a variety of protein sources to replace all but a small portion of fish meal. Substituting the last portion of fish-meal protein with plant-derived products often results in reduced growth rates. Animal renderings from industry, including meat and bone meals, poul- try meals, feather meals, and blood products, have been widely evaluated as substitutes for fish meal, but these products also have limits based on nutrient profiles and nutrient digest