Project description:Analysis of gene expression profiles in liver of obese 11 men/women on 10 days severe calorie-restricted diet and 8 men/women on ad libitum diet. This dataset is part of the TransQST collection.
Project description:We have carried out whole-genome expression profiling of whole blood from obese subjects, defined as obese diet-sensitive and obese diet-resistant, and well matched lean individuals. The diet-sensitive or diet-resistant status refers to the different rates of weight loss observed in the two groups on a low-calorie diet regimen. Bioinformatic analysis revealed alterations in transcription in key pathways that are consistent with impaired capacity for fatty acid oxidation driven mitochondrial ATP synthesis in obese subjects who are resistant to weight loss.
Project description:We have carried out whole-genome expression profiling of whole blood from obese subjects, defined as obese diet-sensitive and obese diet-resistant, and well matched lean individuals. The diet-sensitive or diet-resistant status refers to the different rates of weight loss observed in the two groups on a low-calorie diet regimen. Bioinformatic analysis revealed alterations in transcription in key pathways that are consistent with impaired capacity for fatty acid oxidation driven mitochondrial ATP synthesis in obese subjects who are resistant to weight loss. A total of 80 samples are analyzed. This consists of 20 lean subjects studied at one timepoint and 20 obese subjects (10 diet-sensitive and 10 diet-resistant) studied at 3 timepoints during caloric restriction (day of entry into program, week 3 into the program and week 6 into the program)
Project description:OBJECTIVE Diet intervention in obese adults is the first strategy to induce weight loss and to improve insulin sensitivity. We hypothesized that improvements in insulin sensitivity after weight loss from a short-term dietary intervention tracks with alterations in expression of metabolic genes and abundance of specific lipid species. RESEARCH DESIGN AND METHODS Eight obese, insulin resistant, non-diabetic adults were recruited to participate in a three-week low calorie diet intervention study (1000 kcal/day). Fasting blood samples and vastus lateralis skeletal muscle biopsies were obtained before and after the dietary intervention. Clinical chemistry and measures of insulin sensitivity were determined. Unbiased microarray gene expression and targeted lipidomic analysis of skeletal muscle was performed. RESULTS Body weight was reduced, insulin sensitivity (HOMA-IR) was enhanced, and serum insulin concentration and blood lipid (triglyceride, cholesterol, LDL and HDL) levels were improved after dietary intervention. Gene set enrichment analysis of skeletal muscle revealed that oxidative phosphorylation and inflammatory processes were among the most enriched KEGG-pathways identified after dietary intervention. mRNA expression of PDK4 and MLYCD increased, while SCD decreased in skeletal muscle after dietary intervention. Dietary intervention altered the intramuscular lipid profile of skeletal muscle, with changes in content of phosphatidylcholine and triglyceride species among the pronounced. CONCLUSIONS Short-term diet intervention and weight loss in obese adults alters metabolic gene expression and reduces specific phosphatidylcholine and triglyceride species in skeletal muscle, concomitant with improvements in clinical outcomes and enhanced insulin sensitivity.