Dataset Information

A metabolic associated fatty liver disease risk variant in MBOAT7 regulates toll like receptor induced outcomes [Cut&Tag]

ABSTRACT: The breakdown of toll-like receptor (TLR) tolerance results in tissue damage. Here we provide evidence that membrane bound O-acyltransferase domain containing 7 (MBOAT7) is a crucial negative regulator of TLR signaling. MBOAT7 deficiency in macrophages as observed in patients with metabolic (dysfunction) associated fatty liver disease (MAFLD) and in COVID-19, alters membrane phospholipid composition. We demonstrate that this is associated with a redistribution of arachidonic acid toward proinflammatory eicosanoids, induction of endoplasmic reticulum stress, mitochondrial dysfunction, and remodelling of the accessible inflammatory-related chromatin landscape culminating in macrophage inflammatory responses to TLRs. Activation of MBOAT7 reverses these effects. These outcomes are further modulated by the MBOAT7 rs8736 (T) MAFLD risk variant. Our findings suggest that MBOAT7 can be exploited as a therapeutic target for diseases associated with dysregulation of the TLR signaling cascade.

ORGANISM(S): Homo sapiens

PROVIDER: GSE204964 | GEO | 2022/10/21

REPOSITORIES: GEO

ACCESS DATA

Shared Molecules

Only show the datasets with similarity scores above: 0.5

Threshold

0.5

Similar Datasets

Project description:Non-alcoholic fatty liver disease (NAFLD) is becoming increasingly common and is a leading cause of end stage liver diseases such as cirrhosis and hepatocellular carcinoma. The rise in NAFLD closely parallels the global epidemic of obesity and type 2 diabetes mellitus (T2DM), and there is a clear interrelationship between abnormal lipid metabolism, insulin resistance, and NAFLD progression. Several genetic loci have been identified as contributors to NAFLD progression, all of which are consistently linked to abnormal lipid metabolic processes in the liver. The common loss-of-function variant rs641738 (C>T) near the gene encoding Membrane_x0002_Bound O-Acyltransferase 7 (MBOAT7) is associated with increased susceptibility to NAFLD as well as the entire spectrum of NAFLD progression. The MBOAT7 gene encodes a lipid metabolic enzyme that is capable of esterifying polyunsaturated fatty acyl-CoAs to LPI substrates to generate phosphatidylinositol (PI) lipids. We previously showed that antisense oligonucleotide (ASO)-mediated knockdown of Mboat7 in mice promoted high fat diet-induced hepatic steatosis, hyperinsulinemia, and systemic insulin resistance (Helsley et al., 2019). Thereafter, other groups showed that hepatocyte-specific genetic deletion of Mboat7 promoted striking fatty liver and NAFLD progression but does not alter insulin sensitivity, suggesting the potential for cell autonomous roles. Here, we show that MBOAT7 function in adipocytes contributes to diet- 3 induced metabolic disturbances including hyperinsulinemia and systemic insulin resistance. The expression of Mboat7 in white adipose tissue closely correlates with diet-induced obesity across a panel of ~100 inbred strains of mice fed a high fat/high sucrose diet. Moreover, adipocyte_x0002_specific genetic deletion of Mboat7 is sufficient to promote hyperinsulinemia, systemic insulin resistance, and mild fatty liver. Unlike in the liver, where Mboat7 plays a relatively minor role in maintaining arachidonic acid (AA)-containing PI pools, Mboat7 is the major source of AA_x0002_containing PI pools in adipose tissue. Our data demonstrate that MBOAT7 is a critical regulator of adipose tissue PI homeostasis, and adipocyte MBOAT7-driven PI biosynthesis is closely linked to hyperinsulinemia and insulin resistance in mice.