Dataset Information

Functional analysis of free fatty acid receptor GPR120 in human eosinophils: implications in metabolic homeostasis.

ABSTRACT: Recent evidence has shown that eosinophils play an important role in metabolic homeostasis through Th2 cytokine production. GPR120 (FFA4) is a G protein-coupled receptor (GPCR) for long-chain fatty acids that functions as a regulator of physiological energy metabolism. In the present study, we aimed to investigate whether human eosinophils express GPR120 and, if present, whether it possesses a functional capacity on eosinophils. Eosinophils isolated from peripheral venous blood expressed GPR120 at both the mRNA and protein levels. Stimulation with a synthetic GPR120 agonist, GW9508, induced rapid down-regulation of cell surface expression of GPR120, suggesting ligand-dependent receptor internalization. Although GPR120 activation did not induce eosinophil chemotactic response and degranulation, we found that GW9508 inhibited eosinophil spontaneous apoptosis and Fas receptor expression. The anti-apoptotic effect was attenuated by phosphoinositide 3-kinase (PI3K) inhibitors and was associated with inhibition of caspase-3 activity. Eosinophil response investigated using ELISpot assay indicated that stimulation with a GPR120 agonist induced IL-4 secretion. These findings demonstrate the novel functional properties of fatty acid sensor GPR120 on human eosinophils and indicate the previously unrecognized link between nutrient metabolism and the immune system.

SUBMITTER: Konno Y

PROVIDER: S-EPMC4366258 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Functional analysis of free fatty acid receptor GPR120 in human eosinophils: implications in metabolic homeostasis.

Konno Yasunori Y Ueki Shigeharu S Takeda Masahide M Kobayashi Yoshiki Y Tamaki Mami M Moritoki Yuki Y Oyamada Hajime H Itoga Masamichi M Kayaba Hiroyuki H Omokawa Ayumi A Hirokawa Makoto M

PloS one 20150319 3

Recent evidence has shown that eosinophils play an important role in metabolic homeostasis through Th2 cytokine production. GPR120 (FFA4) is a G protein-coupled receptor (GPCR) for long-chain fatty acids that functions as a regulator of physiological energy metabolism. In the present study, we aimed to investigate whether human eosinophils express GPR120 and, if present, whether it possesses a functional capacity on eosinophils. Eosinophils isolated from peripheral venous blood expressed GPR120 ...[more]

PMID: 25790291

Similar Datasets

Project description:BackgroundOvernutrition and the ensuing hypothalamic inflammation is a major perpetuating factor in the development of metabolic diseases, such as obesity and diabetes. Inflamed neurons of the CNS fail to properly regulate energy homeostasis leading to pathogenic changes in glucose handling, feeding, and body weight. Hypothalamic neurons are particularly sensitive to pro-inflammatory signals derived locally and peripherally, and it is these neurons that become inflamed first upon high fat feeding. Given the prevalence of metabolic disease, efforts are underway to identify therapeutic targets for this inflammatory state. At least in the periphery, omega-3 fatty acids and their receptor, G-protein coupled receptor 120 (GPR120), have emerged as putative targets. The role for GPR120 in the hypothalamus or CNS in general is poorly understood.MethodsHere we introduce a novel, immortalized cell model derived from the rat hypothalamus, rHypoE-7, to study GPR120 activation at the level of the individual neuron. Gene expression levels of pro-inflammatory cytokines were studied by quantitative reverse transcriptase-PCR (qRT-PCR) upon exposure to tumor necrosis factor α (TNFα) treatment in the presence or absence of the polyunsaturated omega-3 fatty acid docosahexaenoic acid (DHA). Signal transduction pathway involvement was also studied using phospho-specific antibodies to key proteins by western blot analysis.ResultsImportantly, rHypoE-7 cells exhibit a transcriptional and translational inflammatory response upon exposure to TNFα and express abundant levels of GPR120, which is functionally responsive to DHA. DHA pretreatment prevents the inflammatory state and this effect was inhibited by the reduction of endogenous GPR120 levels. GPR120 activates both AKT (protein kinase b) and ERK (extracellular signal-regulated kinase); however, the anti-inflammatory action of this omega-3 fatty acid (FA) receptor is AKT- and ERK-independent and likely involves the GPR120-transforming growth factor-β-activated kinase 1 binding protein (TAB1) interaction as identified in the periphery.ConclusionsTaken together, GPR120 is functionally active in the hypothalamic neuronal line, rHypoE-7, wherein it mediates the anti-inflammatory actions of DHA to reduce the inflammatory response to TNFα.

Project description:Comparative analysis of changes in gene and protein expression and fatty acid profiles between Escherichia coli K-12 MG1655 ΔfadD ΔaraBAD expressing an acyl-acyl carrier protein thioesterase from Umbellularia californica (BTE) or a non-functional mutant thioesterase (BTE-H204A) to determine the functional basis for losses in cell viability, membrane integrity, or other stresses and metabolic perturbations that may be present. New hypotheses obtained from the study will assist in metabolic engineering efforts of improved strains exhibiting higher fatty acid yields and productivities. Cultures of fatty acid overproducing (BTE-expressing) and negative control (non-functional BTE-H204A-expressing) strains of Escherichia coli K-12 MG1655 delta-fadD delta-araBAD (deficient in beta-oxidation and L-arabinose catabolism) were sampled under two different sets of media/induction/antibiotic conditions. These conditions were shake flasks at 37C, 250 rpm shaking, in EZ rich defined medium supplemented with 0.2% glucose and 0.01 mM biotin (EZglu), and in fermentors at 37C with controlled air sparging, agitation, and pH in EZ rich defined medium supplemented with 0.4% glycerol and 0.01 mM biotin (EZgly). Two strains were analyzed in the EZglu experiment, the background strain harboring either pTrc99A-BTE (fatty acid overproducing) or pTrc99A-BTE-H204A (control phenotype). Three strains were analyzed in the EZgly experiment, with the background strain haboring either pBAD35-BTE and pBAD33 (fatty acid overproducing), pBAD35-BTE and pBAD33-ACC (fatty acid overproducing, ACC are the 4 subunits of E. coli K-12 acetyl-CoA carboxylase expressed as an artificial operon accDABC in plasmid pBAD33), and pBAD35-BTE-H204A and pBAD33 (control phenotype). RNA was extracted from harvested cell pellets from biological triplicates (EZglu) or biological duplicates (EZgly) of each strain at three different sampling times as defined in each sample description. Due to a hybridization or scanning problem, biological duplicates rather than triplicates were analyzed at the mid-stationary phase sampling point in the EZglu experiment for the control strain harboring pTrc99A-BTE-H204A. Multiple technical replicates at either the hybridization or sample level were analyzed from the biological duplicates of the fermentor experiment. The form of technical replicate (sample or hybridization) is specified in each EZgly sample description.

Dataset Information

Functional analysis of free fatty acid receptor GPR120 in human eosinophils: implications in metabolic homeostasis.

Publications

Functional analysis of free fatty acid receptor GPR120 in human eosinophils: implications in metabolic homeostasis.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets