Neutralization of Oxidized Phospholipids Restrains Nonalcoholic Steatohepatitis
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA575823 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Oxidized phospholipids (OxPL) are pro-inflammatory and pro-atherogenic, but their roles in non-alcoholic steatohepatitis (NASH) are unknown. Here, we show that OxPL accumulate in human and murine NASH. Using a transgenic mouse that expresses a functional single chain variable fragment of E06, a natural antibody that neutralizes OxPL, we demonstrate the casual role of OxPL in NASH. Targeting OxPL in hyperlipidemic Ldlr-/- mice decreased multiple aspects of NASH, including steatosis, inflammation, fibrosis, hepatocyte death and progression to hepatocellular carcinoma. Mechanistically, we found that OxPL promote ROS accumulation to induce mitochondrial dysfunction in hepatocytes. Neutralizing OxPL in AMLN diet-fed Ldlr-/- mice reduced oxidative stress, improved hepatic and adipose tissue mitochondrial function and fatty acid oxidation. Since neutralizing OxPL also protects against atherogenesis, targeting OxPL may be an effective therapeutic strategy for both NASH and atherosclerosis.
2019-11-04 | GSE138419 | GEO
Project description:The genomic landscape of hepatic tissue affected by nonalcoholic steatohepatitis (NASH) in severely obese adolescents undergoing bariatric surgery is unknown. Our purpose here was to uncover genomic profiles of obese controls, and obese cases with nonalcoholic fatty liver disease (NAFLD), borderline nonalcoholic steatohepatitis, and definite nonalcoholic steatohepatitis, in order to clarify molecular functions, biological processes, and pathways that are dysregulated in nonalcoholic steatohepatitis in the severely obese adolescent. In a prospective observational cohort study, we have intra-operatively obtained 165 liver samples; of these 67 were submited for microarray analysis. Through ANOVA, we found 8648 genes with differential regulation between the four histologies; from these, we uncovered gene signatures shared between borderline and definite nonalcoholic steatohepatitis, and gene sets with differential effects between borderline and definite.
2017-07-21 | GSE66676 | GEO
Project description:Myeloid FoxO1 in Nonalcoholic Steatohepatitis
| PRJNA839093 | ENA
Project description:To investigate the effects of AAV8-mediated overexpression of AGXT in mice with diet-induced nonalcoholic steatohepatitis compared to AAV8-GFP
2023-02-19 | GSE224097 | GEO
Project description: Not available
| S-EPMC7028360 | biostudies-literature
Project description:Purpose: We investigated the tetrachloroethylene associated changes in kidney transcriptomes among healthy mice, nonalcoholic fatty liver disease mice, and nonalcoholic steatohepatitis mice.
2019-02-13 | GSE115641 | GEO
Project description:Long wavelength Ultraviolet (UVA-1) radiation causes oxidative stress that leads to the formation of noxious substances within the skin. As a defensive mechanism skin cells produce detoxifying enzymes and antioxidants when they detect modified molecules. We have recently shown that UVA-1 irradiation oxidizes the abundant membrane phospholipid 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphorylcholine (PAPC), which then induced the synthesis of the stress response protein heme oxygenase 1 (HO-1) in dermal fibroblasts. Here we examined the effects of UVA-1 and (UV-) oxidized phospholipids on the global gene expression in human dermal fibroblasts. We identified a cluster of genes that were co-induced by UVA-1-oxidized PAPC and UVA-1 radiation. The cluster included HO-1, glutamate-cysteine ligase modifier subunit (GCLM), aldo-keto reductases-1-C1 and -C2 (AKR1C1, AKR1C2), and interleukin 8 (IL8). These genes are members of the cellular stress response system termed âantioxidant responseâ or âPhase II detoxificationâ. Accordingly, the regulatory regions of all these genes contain binding sites for NF-E2-related factor 2 (Nrf2), a major regulator of the antioxidant response. Both UVA-1 irradiation and treatment with oxidized lipids led to increased nuclear accumulation of Nrf2. Silencing expression of Nrf2 using siRNA or using cells and tissue from Nrf2-deficient mice, we show that the induction of the co-regulated genes was suppressed. Expression of other canonical UVA-1-induced genes, including cyclooxygenase 2 (Cox2) and interleukin 6 (IL6) was unaltered in the absence of Nrf2. Together, our data show that UVA-1-mediated lipid oxidation induces induction of antioxidant response genes, which is dependent on the redox-regulated transcription factor Nrf2. To activate Nrf2 is a major strategy for novel antioxidant drugs, the skin photo-adaptation (SPA) inducers. Our finding that specific uv-oxidized lipids act similar sheds a new (ultraviolet) light on the usually detrimental âimageâ of UV generated lipid mediators. Experiment Overall Design: we profiled global mRNA expression levels in human dermal fibroblasts that had been treated with either UVA-1 or oxidized lipids. To investigate the effect of oxidized phospholipids on gene regulation, we used two preparations, which differed in their degree of oxidation; the minimally oxidized UV-PAPC resulting from UVA-1 irradiation of PAPC, and air-oxidized PAPC (OxPAPC), which represents the full spectrum of oxidation products (Gruber 07) (Reis et al., 2005). We irradiated dermal fibroblasts with UVA-1 (40J/cm²) or treated them with UV-PAPC, OxPAPC or native PAPC (100µg/ml each). We analyzed global gene expression four hours after stimulation with gene arrays (Affymetrix U133A Plus 2.0 Gene Chips).
2009-11-10 | E-GEOD-13606 | biostudies-arrayexpress
Project description:The danger signals that activate the NLRP1 inflammasome have yet to be firmly established. NLRP1 undergoes autoproteolysis to generate N-terminal (NT) and C-terminal (CT) fragment, which importantly, is a necessary step for its check-point regulation by the DPP9 ternary complex and the mechanistic activation of NLRP1 through functional degradation. Here, we report an added layer of regulatory complexity to NLRP1 activity, in the form of a repressive interaction that NLRP1 forms with the oxidized, but not reduced, form of thioredoxin-1 (TRX1). Loss of TRX1 destabilizes the NT fragment of NLRP1 and promotes enhanced inflammasome activation. The TRX1 interaction occurs through the NACHT-LRR of NLRP1 and requires nucleotide binding in its ATPase domain. In addition, we found that several patient-derived and ATPase-inactivating mutations in the NACHT-LRR region hyperactive the inflammasome by destabilize protein folding and are also shown to abrogate TRX1 binding. Thus, NLRP1 appears to detect intracellular reductive stress through a decrease in the fraction of intracellular oxidized TRX1, which enhances protein disorder, leading to inflammasome signaling. These findings link the cellular redox environment to NLRP1-mediated innate immunity.
2022-11-04 | GSE215035 | GEO
Project description:Hepatic microRNA signatures in experimental nonalcoholic steatohepatitis
| PRJNA557444 | ENA
Project description:Non-alcoholic fatty liver disease (NAFLD) is the number one cause of chronic liver disease worldwide, with 25% of these patients developing nonalcoholic steatohepatitis (NASH). NASH significantly increases the risk of cirrhosis and decompensated liver failure. Past studies in rodent models have shown the knockout of glycine-N-methyltransferase (GNMT) results in rapid pro-gression of steatosis, fibrosis, and hepatocellular carcinoma. However, the attenuation of GNMT in subjects with NASH and the molecular basis for its impact on the disease process are still unclear. To address this knowledge gap, we show the reduction of GNMT protein levels in the liver of NASH subjects compared to healthy controls. To gain insight into the impact of decreased GNMT in the disease process, we performed global label-free proteome studies on the livers from a murine Western diet-based model of NASH. Histological and molecular characterization of the animal model demonstrate high resemblance to the human disease.
2022-04-04 | PXD030781 | Pride