Project description:Analysis of rectus femoris samples from chidren with obesity and normal weight. Obese children display insulin resistance (IR) and other metabolic abnormalities at higher rates than do normal weight children. Results provide insight into the molecular mechanisms underlying the pathogenesis of childhood obesity.
Project description:Epigenetics presents a dynamic approach to assess complex individual variation in obesity susceptibility. However, few studies have examined epigenetic patterns in preschool-age children, despite the relevance of this developmental stage to trajectories of weight gain, because of difficulties obtaining blood tissue samples. This proof of principle study examined DNA methylation in 92 saliva samples, comparing Latino preschool children of normal weight mothers (Body Mass Index [BMI] <27 kg/m2 and WC <90 cm) to children of obese mothers (BMI >30 kg/m2 and WC >100 cm). We hypothesized that salivary DNA methylation patterns in Latino preschool age children born of normal weight vs obese weight mothers would be: 1) associated with maternal BMI phenotype in continuous linear regression analysis; 2) saliva could demonstrate epigenetic variation across individuals; and 3) preschool child saliva would be differentially methylated when comparing those children with obese versus normal weight mothers. One hundred and nineteen CpG sites were significantly (p-value <1.56 X 10-5, p-value adjusted <.05) associated with maternal BMI in linear regression models controlling for child’s age, gender, and BMI. Of these 119 CpG sites, 41 were found within the transcription start site, 5’ UTR, 3’ UTR, or another regulatory region outside of the gene body. Saliva, a practical human tissue to obtain in naturalistic settings and in pediatric populations, was confirmed to be a viable medium for genome-wide epigenetic testing with maternal weight. Although not identical to results yielded from other human tissue types (i.e., cord blood samples), saliva findings indicate potential epigenetic differences in Latino preschool children at risk for pediatric obesity.
Project description:Epigenetics presents a dynamic approach to assess complex individual variation in obesity susceptibility. However, few studies have examined epigenetic patterns in preschool-age children, despite the relevance of this developmental stage to trajectories of weight gain, because of difficulties obtaining blood tissue samples. This proof of principle study examined DNA methylation in 92 saliva samples, comparing Latino preschool children of normal weight mothers (Body Mass Index [BMI] <27 kg/m2 and WC <90 cm) to children of obese mothers (BMI >30 kg/m2 and WC >100 cm). We hypothesized that salivary DNA methylation patterns in Latino preschool age children born of normal weight vs obese weight mothers would be: 1) associated with maternal BMI phenotype in continuous linear regression analysis; 2) saliva could demonstrate epigenetic variation across individuals; and 3) preschool child saliva would be differentially methylated when comparing those children with obese versus normal weight mothers. One hundred and nineteen CpG sites were significantly (p-value <1.56 X 10-5, p-value adjusted <.05) associated with maternal BMI in linear regression models controlling for childâs age, gender, and BMI. Of these 119 CpG sites, 41 were found within the transcription start site, 5â UTR, 3â UTR, or another regulatory region outside of the gene body. Saliva, a practical human tissue to obtain in naturalistic settings and in pediatric populations, was confirmed to be a viable medium for genome-wide epigenetic testing with maternal weight. Although not identical to results yielded from other human tissue types (i.e., cord blood samples), saliva findings indicate potential epigenetic differences in Latino preschool children at risk for pediatric obesity. This proof of principle study examined DNA methylation in 92 saliva samples, comparing Latino preschool children of normal weight mothers (Body Mass Index [BMI] <27 kg/m2 and WC <90 cm) to children of obese mothers (BMI >30 kg/m2 and WC >100 cm). Antropometry was measured objectively according to a standardized protocol.Saliva from preschool Latino children at risk for obesity (BMI>50% < 95% participating in WIC/SNAP programs) was collected using the Oragene DNA saliva kit following a strict data collection protocol. DNA extraction was performed as per DNA Genotek's recommendations using the PrepIT L2P reagent. Extracted DNA was stored in individually barcoded cryovials at â80 degrees Fahrenheit. For children, saliva was obtained using the âbaby brushâ approach, in which small sponges attached to plastic handles are inserted between cheek and gumline to absorb saliva .Arrays were processed using standard protocol [34], with 3 samples randomly selected to serve as duplicates and 1 sample run with HapMap DNA to test functionality of reagents. Duplicates were measured for high technique consistency with Pearson correlation coefficient (>.99). Methylation data were quality controlled using Illumina GenomeStudio (V2011.1), Methylation module (V1.9.0). Samples with lower than 98% call rate (i.e. <485,000 probes) were excluded. Any non-specific cross-reacting probes, probes carrying common SNPs (MAF >1%), or any probes with p-values greater than 0.05 for more than 20% of the sample were sequentially excluded. Validation via pyrosequencing was conducted.
Project description:Injury of skeletal muscle is a common occurence affecting millions worldwide. Injuries usually are not major incisions into daily life, however, the underlying health varies e. g. due to obesity. Obesity is usually accompanied by excessive and dysfunctional lipid depots, chronic low-grade inflammation as well as several co-morbidities, which are able to impair the regeneration of skeletal muscle. A blunt injury approach was used to damage mouse skeletal muscle of the extensor iliotibialis anticus in both obese and normal weight C57BL/6J mice. Microarray analysis was used to assess the molecular fingerprint in different stages of muscle regeneration while observing different health conditions.
Project description:Intrauterine growth restriction (IUGR) is a leading cause of neonatal morbidity and mortality in humans and domestic animals. Developmental adaptations of skeletal muscle in IUGR lead to increased risk of premature muscle loss and metabolic disease later during life. Although transcriptome-wide profiles in muscle associated with IUGR have been reported, their regulation by miRNAs is not well understood. The aim of this study was to identify differences in miRNA expression in porcine skeletal muscle of IUGR and normal-weight (NW) littermates during late foetal development (day 90 of gestation).
Project description:Genome wide DNA methylation profiling of peripheral blood samples from 41 children with simple obesity and 31 normal controls. The Illumina Infinium MethylationEPIC BeadChip (Illumina 850k, San Diego, CA) was used to obtain DNA methylation profiles across greater than 850,000 CpG sites across the genome. Samples included 31 normal and 41 obesity peripheral blood.
Project description:We investigated the effect of weight loss maintenance (WLM) and weight regain on skeletal muscle in rodents. In skeletal muscle of obesity prone rats, WLM reduced fat oxidative capacity and down-regulated genes involved in fat metabolism. After weight was regained in rats, the genes involved in fat metabolism were still reduced. Mice with skeletal muscle lipoprotein lipase overexpression (mCK-hLPL), which augments fat metabolism, were subjected to our WLM and weight regain paradigm. We found that mCK-hLPL attenuated weight regain by potentiating energy expenditure.Irrespective of genotype, weight regain suppressed dietary fat oxidation and down-regulated genes involved in fat metabolism in skeletal muscle. However, mCK-hLPL mice oxidized more fat throughout weight regain and had greater expression of genes involved in fat metabolism and lower expression of genes involved in carbohydrate metabolism during WLM and regain.