Project description:Sudden cardiac death (SCD) associated with heart failure (HF) is a multifactorial problem requiring a systems level approach applied to suitable experimental animal models with features of the human disease. Here we examine key regulatory pathways underlying the transition from compensated hypertrophy (HYP) to decompensated HF and SCD by integrated analysis of the transcriptome, proteome and metabolome. In a guinea pig model of acquired long QT syndrome and HF/SCD, relative protein abundances from sham-operated, HYP and HF hearts were assessed using isobaric tags for relative and absolute quantification (iTRAQ), prior to liquid chromatography and tandem mass spectrometry (LC-MS/MS). Metabolites were quantified by LC-MS/MS or gas chromatography coupled to MS (GC-MS). Transcriptome profiles were obtained using DNA microarrays. The guinea pig HF proteome exhibited classic biosignatures of cardiac HYP, left ventricular dysfunction, fibrosis, cellular degeneration, inflammation and extravasation. Fatty acid metabolism, mitochondrial transcription/translation factors, antioxidant enzymes, and other mitochondrial processes, were downregulated in HF, but not HYP. Proteins upregulated in HF are consistent with extracellular matrix remodeling, cytoskeletal remodeling, and acute phase inflammation markers. Among metabolites, downregulation of acyl-carnitines was observed in HYP, while fatty acids accumulated in HF. Levels of the tricarboxylic acid (TCA) cycle metabolite, citrate, and the potent inhibitor, 2-methylcitrate, increased upon transition from HYP to HF. Correlation of the magnitude of transcript and protein changes in HF is weak (R2=0.23), indicating that targeting transcript/proteome may reveal inform post-transcriptional gene regulation in HF. Proteome/Metabolome integration suggests metabolic bottlenecks in fatty acyl-CoA processing by carnitine palmitoyl transferase (CPT1B) as well as TCA cycle inhibition. We present a model in which hallmarks of acute signaling in HF, including Ca2+ dysregulation and low cAMP levels, are coupled to mitochondrial metabolic and antioxidant defects, through a CREB/PGC1-alpha transcriptional axis.
Project description:Illumina single-end sequencing of Hela_2 (HeLa cell line). While the number and identity of proteins expressed in a single human cell type is currently unknown, this fundamental question can be addressed by advanced mass spectrometry (MS)-based proteomics. On-line liquid chromatography coupled to high resolution MS and MS/MS yielded more than 150,000 unique peptides that identified more than 10,000 different human proteins encoded by more than 9,000 human genes. Deep transcriptome sequencing revealed transcripts for nearly all detected proteins. We show that the abundances of more than 90% of proteins and transcripts fall within a 10,000-fold range, and allocate the proteome to different compartments, complexes and functions. Comparisons of the proteome and the transcriptome, and analysis of protein complex databases and GO categories, suggest that we achieved almost complete coverage of the functional transcriptome and the proteome of a single cell type.
Project description:RNA sequencing of A431 cell line samples before and after gefitinib treatment, at 0, 2, 6 and 24 hours, was performed in order to characterize the cell line's early and late response to this drug, and to compare against proteomics (mass spectrometry) characterization of the cell line using the same setup. These data were used in Branca et al., HiRIEF LC-MS enables deep proteome coverage and unbiased proteogenomics., Nat Methods. 2014 Jan;11(1):59-62 (doi: 10.1038/nmeth.2732).
Project description:The cardioprotective effects of long chain (LC) 3PUFA can be achieved at the gene expression level, notably in liver. However, the complexity of biological pathways modulations and the nature of the bioactive molecules are still under investigation. The present study aimed to investigate the dose-response effects of LC 3PUFA on the production of peroxidated metabolites and on global gene expression in liver. The intake of LC ?3PUFA increased, in a dose-dependent manner, their incorporation in liver phospholipids but also the hepatic production of 4-HHE. Pathways related to inflammation were dose-dependently associated with the 3 groups but Group 2 was rather associated with inflammatory effects while Group 3 was anti-inflammatory. LC ?3PUFA had no effect on PPAR-controlled genes. However, they modified, in a dose-dependent manner, the expression of major genes related to lipoprotein metabolism (LDLR, VLDLR, INSIG1 and MTTP), possibly through the FXR signaling pathway. In conclusion, the effect of LC ?3PUFA is dependent on the dose possibly because of the production of peroxidated metabolites such as 4-HHE. New-Zealand white rabbits were fed (7 wk) a high cholesterol diet and received by daily oral gavages either oleic acid rich oil or a mixture of oils providing 0.1% (Group 1), 0.5% (Group 2) or 1% (Group 3) of energy as docosahexaenoic acid. Specific peroxidated metabolite issued from LC 3PUFA (4-hydroxyhexenal or 4-HHE) were measured by GC/MS/MS and transcription profiling was conducted in liver. Differentially expressed genes were identified using Bioconductor (Moderated p<0.05, Fold Change>1.20) and clustered into pathways (Ingenuity Pathway Analysis 7.0).