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Obesity and type 2 diabetes have a heritable component that is not attributable to genetic factors. Instead, epigenetic mechanisms may play a role. We have developed a mouse model of intrauterine growth restriction (IUGR) by in utero malnutrition. IUGR mice developed obesity and glucose intolerance with aging. Strikingly, offspring of IUGR male mice also developed glucose intolerance. Here, we show that in utero malnutrition of F1 males influenced the expression of lipogenic genes in livers of F2 mice, partly due to altered expression of Lxra. In turn, Lxra expression is attributed to altered DNA methylation of its 5' UTR region. We found the same epigenetic signature in the sperm of their progenitors, F1 males. Our data indicate that in utero malnutrition results in epigenetic modifications in germ cells (F1) that are subsequently transmitted and maintained in somatic cells of the F2, thereby influencing health and disease risk of the offspring.

Background: Fatty liver is highly prevalent among obese children and represents a major risk factor for chronic liver diseases and severe metabolic complications.Methods: We randomly assigned 17 obese children 8-17 years of age with fatty liver to either an experimental low-glycemic-load or conventional low-fat diet for 6 months. Participants in both groups received nutrition education and behavioral counseling of equal intensity. The primary outcome was hepatic lipid content measured by proton magnetic resonance spectroscopy. Secondary outcomes included change in visceral fat, BMI, anthropometrics, alanine aminotransferase (ALT), and insulin resistance.Results: A total of 16 participants completed the study. Reported glycemic load decreased in the low-glycemic-load group and reported dietary fat decreased in the low-fat group. At baseline, liver fat was 23.8% [standard deviation (SD) 12.2] in the lowglycemic-load group and 29.3% (14.1) in the low-fat group. Liver fat decreased substantially in both groups at 6 months expressed as absolute percentage change, with no between-group differences [ -8.8 (standard error (SE) 4.1) vs. -10.5 (3.7)%, respectively, p = 0.76 for group · time interaction]. Secondary outcomes also improved on both diets, with no between-group differences. Baseline and change in ALT were strongly associated with hepatic fat content.Conclusions: Weight-reducing diets focused either on glycemic load or dietary fat improved hepatic steatosis over 6 months. Additional research is needed to determine whether these diets differ in effectiveness over the long term.Trial Registration: clinicaltrials.gov Identifier: NCT00480922

Epidemiological and clinical data show that rapid weight gain early in life is strongly associated with several components of the metabolic syndrome. Strikingly, abnormal growth rates in early life can additionally influence diabetes risk in subsequent generations. Here we aim to study whether neonatal overgrowth induces diabetes in offspring and grand-offspring of affected individuals using a mouse model of neonatal overfeeding. We induced neonatal overgrowth (ON-F0) by culling offspring to four pups per dam during lactation. By age 4 months, ON-F0 mice developed many features of the metabolic syndrome, including obesity, insulin resistance, and glucose intolerance. We then studied whether male offspring (ON-F1) and grand-offspring (ON-F2) of ON-F0 male mice, which were not overfed during lactation, developed features of the metabolic syndrome with aging. ON-F1 mice developed fed and fasting hyperinsulimemia, hypertryglyceridemia, insulin resistance, and glucose intolerance, but not obesity, by age 4 months. In contrast, ON-F2 male mice showed a more moderate phenotype and only developed fasting hyperglycemia and glucose intolerance by age 4 months. Impaired glucose tolerance in ON-F1 and ON-F2 mice appeared to be accounted for primarily by peripheral insulin resistance, because beta-cell function remained normal or even increased in these cohorts. Nutritional challenges occurring during sensitive periods of development may have adverse metabolic consequences well beyond the lifespan of affected individuals and manifest in subsequent generations. Transgenerational progression of metabolic phenotypes through the male lineage supports a potential role for epigenetic mechanisms in mediating these effects.

Gas chromatography coupled to mass spectrometry (GC/MS) has been a long-standing approach used for identifying small molecules due to the highly reproducible ionization process of electron impact ionization (EI). However, the use of GC-EI MS in untargeted metabolomics produces large and complex data sets characterized by coeluting compounds and extensive fragmentation of molecular ions caused by the hard electron ionization. In order to identify and extract quantitative information on metabolites across multiple biological samples, integrated computational workflows for data processing are needed. Here we introduce eRah, a free computational tool written in the open language R composed of five core functions: (i) noise filtering and baseline removal of GC/MS chromatograms, (ii) an innovative compound deconvolution process using multivariate analysis techniques based on compound match by local covariance (CMLC) and orthogonal signal deconvolution (OSD), (iii) alignment of mass spectra across samples, (iv) missing compound recovery, and (v) identification of metabolites by spectral library matching using publicly available mass spectra. eRah outputs a table with compound names, matching scores and the integrated area of compounds for each sample. The automated capabilities of eRah are demonstrated by the analysis of GC-time-of-flight (TOF) MS data from plasma samples of adolescents with hyperinsulinaemic androgen excess and healthy controls. The quantitative results of eRah are compared to centWave, the peak-picking algorithm implemented in the widely used XCMS package, MetAlign, and ChromaTOF software. Significantly dysregulated metabolites are further validated using pure standards and targeted analysis by GC-triple quadrupole (QqQ) MS, LC-QqQ, and NMR. eRah is freely available at http://CRAN.R-project.org/package=erah .

Decreased circulating sphingolipid-related metabolites were associated with lifestyle intervention in prepubertal children with obesity, and correlated to improvements in HbA1c.

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These results indicate that lifestyle intervention decreases TMAO levels in children with obesity.