Impact of Visceral Fat on Gene Expression Profile in Peripheral Blood Cells
ABSTRACT: We profiled gene expression in peripheral blood cells from 28 obese patients by microarray analysis and visceral fat accumulation caused the gene expression proliles especially in circadian rhythm, inflammation, oxidative stress, and immune response. Obesity was defined as body mass index (BMI) greater than 25 kg/m2 according to the Japanese criteria and visceral fat area (VFA) was estimated by abdominal bioelectrical impedance analysis. Subjects with type 1 diabetes mellitus, autoimmune diseases, malignant diseases, and infectious diseases were excluded. Patients treated with statin and/or thiazolidinediones were also excluded.
Project description:We profiled gene expression in peripheral blood cells from 17 obese patients by microarray analysis and revealed that visceral fat adiposity impact on gene expression profile in peripheral blood cells compared to subcutaneous fat accumulation. Overall design: Obesity was defined as body mass index (BMI) greater than 25 kg/m2 according to the Japanese criteria. Visceral fat area (VFA) and subcutaneous fat area (SFA) were measured by computed tomography (CT) and determined in the cross-sectional slice at the umbilical level. Subjects with type 1 diabetes mellitus, malignant diseases, autoimmune diseases, and infectious diseases were excluded. Patients treated with anti-diabetic drugs were also excluded.
Project description:We profiled gene expression in peripheral blood cells from 28 obese patients by microarray analysis and visceral fat accumulation caused the gene expression proliles especially in circadian rhythm, inflammation, oxidative stress, and immune response. Overall design: Obesity was defined as body mass index (BMI) greater than 25 kg/m2 according to the Japanese criteria and visceral fat area (VFA) was estimated by abdominal bioelectrical impedance analysis. Subjects with type 1 diabetes mellitus, autoimmune diseases, malignant diseases, and infectious diseases were excluded. Patients treated with statin and/or thiazolidinediones were also excluded.
Project description:Rationale: Obstructive sleep apnea (OSA) has been associated with metabolic dysregulation and systemic inflammation. This may be due to pathophysiologic effects of OSA on visceral adipose tissue. We sought to assess the transcriptional consequences of OSA on adipocytes by utilizing pathway-focused analyses. Methods: Patients scheduled to undergo ventral hernia repair surgery were recruited to wear a portable home sleep monitor for two nights prior to surgery. Visceral fat biopsies were obtained intra-operatively. RNA was extracted and whole-genome expression profiling was performed. Gene Set Enrichment Analysis (GSEA) was used to identify curated gene sets that were differentially enriched in OSA subjects. Network analysis was applied to a select set of highly enriched pathways. Results: 10 patients with OSA and 8 control subjects were recruited. There were no differences in age, gender, body mass index between the two groups, but the OSA subjects had a significantly higher respiratory disturbance index (19.2 vs. 0.6, P-value 0.05) and worse hypoxemia (minimum oxygen saturation 79.7% vs. 87.8%, P-value < 0.001). GSEA identified a number of gene sets up-regulated in adipose tissue of OSA patients including the pro-inflammatory NF-κB pathway and the proteolytic ubiquitin/proteasome module. A critical metabolic pathway, the peroxisome proliferator-activated receptor (PPAR), was down-regulated in subjects with OSA. Network analysis linked members of these modules together and identified regulatory hubs. Conclusions: OSA is associated with alterations in visceral fat gene expression. Pathway-based network analysis highlighted perturbations in several key pathways whose coordinated interactions may contribute to the metabolic dysregulation observed in this complex disorder. Total RNA from visceral fat of 18 subjects (10 OSA, 8 Control) was hybridized to 18 Affymetrix Genechip Human Gene 1.0 ST microarrays.
Project description:Microgravity is one of the most important features in spaceflight. Previous evidence has shown that significant changes to the musculoskeletal and immune systems occurred under microgravity. The present study was undertaken to explore the change in protein abundance in human colon colorectal cells that were incubated for 48 or 72 h either in normal conditions and µG simulated conditions. The comparative proteomic method based on the 18O labeling technique was applied to investigate the up-regulated proteins and down-regulated proteins in SH-SY5Y under simulated microgravity.
Project description:Plasma-derived extracellular vesicles (EVs) have been extensively described as putative biomarkers in different diseases. More precisely, increased levels of EVs subpopulations are well-known to associate with obesity. The goal of this study was to identify EVs-derived biomarkers in plasma from obese patients in order to predict the development of pathological events associated with obesity. The study was performed combining two different proteomic approaches (2D-DIGE and label-free LC-MS/MS). Samples were obtained from 22 obese patients, with no associated comorbidities, and their lean-matched controls. EVs were isolated following a serial ultracentrifugation protocol. We detected 22 and 23 different regulated protein features from 2D-DIGE and label free LC-MS/MS respectively. Most of the differentially regulated proteins identified were involved in the coagulation and complement cascade. Interestingly, there was a clear up-regulation of complement C3, complement C4 and fibrinogen in obese patients following both approaches, which correlates with a pro-inflammatory and prothrombotic state of those individuals. On the other hand, we showed a down-regulation of adiponectin leading to an increased risk of suffering cardiovascular diseases. Our results suggest the relevance of considering plasma-derived-EVs proteins as a source of potential biomarkers for the development of atherothrombotic events in obesity.
Project description:Methyl ketone production by P. putida with A. thaliana and switchgrass hydrolysates obtained by dilute acid pretreatment led to the identification of plant-derived amino acids, rather than mono-aromatics, as key stimulative components of these hydrolysates. Shotgun proteomics indicated that the amino acids had a specific inductive effect on proteins involved in fatty acid biosynthesis, leading to a 9-fold increase in methyl ketone titer when amending glucose-containing minimal medium with a defined set of amino acids.
Project description:In this work, we developed processes using ionic liquids to obtain size-defined soluble aromatic-rich streams from sorghum biomass to assess their biocompatibility with P. putida. Growth was unexpectedly higher than that observed on a main aromatic compound. Subsequently, proteomics and metabolomics analysis revealed that BCD liquor contains additional carbon sources except aromatics. Our comparative proteomic analysis first revealed significant up-regulation of a diverse set of proteins in P. putida grown in the complex lignolysate to understand their function and regulation.
Project description:Chemical crosslinking mass spectrometry is rapidly emerging as a prominent technique to study protein structures. Structural information is obtained by covalently connecting peptides in close proximity by small reagents and identifying the resulting peptide pairs by mass spectrometry. However, sub-stoichiometric reaction efficiencies render routine detection of crosslinked peptides problematic. Here we present a new tri-functional crosslinking reagent, termed PhoX, which is decorated with a stable phosphonic acid handle. This makes the crosslinked peptides amenable to the well-established IMAC enrichment. The handle allows for 300x enrichment efficiency and 97% specificity, dramatically reducing measurement time and improving data quality. We exemplify the approach on various model proteins and protein complexes, e.g. resulting in a structural model of LRP1/RAP complex. PhoX is also applicable to whole cell lysates. When focusing the database search on ribosomal proteins, our first attempt resulted in 355 crosslinks, out-performing current efforts in less measurement time.
Project description:Global gene expression in the 20-week remnant kidneys of uninephrectomized mice fed either a chow or a high fat diet was compared with kidney tissue from the corresponding sham groups. Results provide insight into mechanisms underlying effects of high-fat induced obesity on gene expression in mouse kidney. Male C57/BJ mice aged 6 weeks were randomly assigned to uninephrectomy (UNX) or sham procedures and fed with a high fat diet or control chow diet. All mice were sacrificed under anesthesia 20 weeks after surgery and kidneys were harvested. 3-4 total RNA samples per group were analyzed and gene expression was compared between groups.
Project description:In order to identify new key molecules in the pathogenesis of myxoid liposarcoma, we performed comparative gene expression profiling in myxoid liposarcoma and fat tissue samples. Whole genome microarray analysis was performed on eight primary myxoid liposarcoma samples and an RNA pool of eight healthy fat tissue samples.