Differential intracellular calcium influx, nitric oxide production, ICAM-1 and IL8 expression in primary bovine endothelial cells exposed to nonesterified fatty acids

Abstract

BackgroundNonesterified fatty acids (NEFAs) are involved in proinflammatory processes in cattle, including in the increased expression of adhesion molecules in endothelial cells. However, the mechanisms underlying these effects are still unknown. The aim of this study was to assess the effects of NEFAs on the intracellular calcium (Ca2+i) influx, nitric oxide production, and ICAM-1 and IL-8 expression in primary bovine umbilical vein endothelial cells (BUVECs).ResultsMyristic (MA), palmitic (PA), stearic (SA), oleic (OA) and linoleic acid (LA) rapidly increased Ca2+i. The calcium response to all tested NEFAs showed an extracellular calcium dependence and only the LA response was significantly inhibited until the intracellular calcium was chelated. The EC50 values for MA and LA were 125 μM and 37 μM, respectively, and the MA and LA effects were dependent on calcium release from the endoplasmic reticulum stores and on the L-type calcium channels. Only the calcium response to MA was significantly reduced by GW1100, a selective G-protein-coupled free fatty acid receptor (GPR40) antagonist. We also detected a functional FFAR1/GPR40 protein in BUVECs by using western blotting and the FFAR1/GPR40 agonist TAK-875. Only LA increased the cellular nitric oxide levels in a calcium-dependent manner. LA stimulation but not MA stimulation increased ICAM-1 and IL-8-expression in BUVECs. This effect was inhibited by GW1100, an antagonist of FFAR1/GPR40, but not by U-73122, a phospholipase C inhibitor.ConclusionsThese findings strongly suggest that each individual NEFA stimulates endothelial cells in a different way, with clearly different effects on intracellular calcium mobilization, NO production, and IL-8 and ICAM-1 expression in primary BUVECs. These findings not only extend our understanding of NEFA-mediated diseases in ruminants, but also provide new insight into the different molecular mechanisms involved during endothelial cell activation by NEFAs.Electronic supplementary materialThe online version of this article (doi:10.1186/s12917-016-0654-3) contains supplementary material, which is available to authorized users.

Intestinal Dysbiosis Is Associated with Altered Short-Chain Fatty Acids and Serum-Free Fatty Acids in Systemic Lupus Erythematosus

“…Taking into account the effects of FFA on inflammation, oxidative stress, and expression of adhesion molecules (51–53), our results may support a role for FFA as a link between the (altered) gut microbiota, host metabolism, and disease status. It is interesting to note that differences among FFA in their ability to promote endothelial activation in vivo or in vitro have been demonstrated (54–56), which is in line with the associations found in our study. Importantly, these biomarkers are considered as early preclinical indicators of CVD development in the long term (57–60).…”

Differential free fatty acid receptor-1 (FFAR1/GPR40) signalling is associated with gene expression or gelatinase granule release in bovine neutrophils

“…49,53 Our recent study in bovine endothelial cells showed that LA increased IL-8 mRNA, and GW1100 significantly reduced LA-induced IL-8. 54 From our analysis using the MAPK and PI3K inhibitors in FFAR1/GPR40 agonist-treated neutrophils ( Supplementary Figure), we did not observe a reduction in COX-2 or IL-8 expression, although a trend towards a decrease in some experiments was observed, which indicates that the inhibition of a single pathway is not enough to reduce the levels of COX-2 or IL-8. Finally, we studied whether the MAPK or PI3K pathways could play roles in MMP-9 release because MAPK and Akt phosphorylation are rapid events and MMP-9 release also occurs quickly, 8,39,40 because active MMP-9 is stored in granules into neutrophils.…”

“…49,53 Our recent study in bovine endothelial cells showed that LA increased IL-8 mRNA, and GW1100 significantly reduced LA-induced IL-8. 54 From our analysis using the MAPK and PI3K inhibitors in FFAR1/GPR40 agonist-treated neutrophils (Supplementary Figure), we did not observe a reduction in COX-2 or IL-8 expression, although a trend towards a decrease in some experiments was observed, which indicates that the inhibition of a single pathway is not enough to reduce the levels of COX-2 or IL-8.…”

Long Chain Fatty Acids as Modulators of Immune Cells Function: Contribution of FFA1 and FFA4 Receptors

“…It is highly expressed in human β-pancreatic cells (Itoh et al, 2003 ) and gut enteroendocrine responsible for glucagon-like peptide-1 (GLP-1) and peptide hormone YY (PYY) (Milligan et al, 2017 ). In addition, the FFA1 receptor is expressed in several tissues, such as those of the heart, skeletal muscle, liver, bone, brain, epithelial mammary cells, endothelial cells, macrophages, monocytes, and neutrophils (Briscoe et al, 2003 ; Kotarsky et al, 2003 ; Yonezawa et al, 2004 , 2008 ; Cornish et al, 2008 ; Manosalva et al, 2015 ; Loaiza et al, 2016 ; Agrawal et al, 2017 ; Souza et al, 2020 ). Since FFA1 receptor agonists in β-pancreatic cells increase glucose-dependent insulin release (Briscoe et al, 2003 ; Itoh et al, 2003 ), basic FFA1 receptor-related research has mainly focused on investigating its potential use in diabetes mellitus therapy (Burant, 2013 ; Mohammad, 2016 ).…”