Dietary arachidonate in milk replacer triggers dual benefits of PGE2 signaling in LPS-challenged piglet alveolar macrophages.

ABSTRACT: Background:Respiratory infections challenge the swine industry, despite common medicinal practices. The dual signaling nature of PGE2 (supporting both inflammation and resolution) makes it a potent regulator of immune cell function. Therefore, the use of dietary long chain n-6 PUFA to enhance PGE2 effects merits investigation. Methods:Day-old pigs (n?=?60) were allotted to one of three dietary groups for 21?d (n?=?20/diet), and received either a control diet (CON, arachidonate?=?0.5% of total fatty acids), an arachidonate (ARA)-enriched diet (LC n-6, ARA?=?2.2%), or an eicosapentaenoic (EPA)-enriched diet (LC n-3, EPA?=?3.0%). Alveolar macrophages and lung parenchymal tissue were collected for fatty acid analysis. Isolated alveolar macrophages were stimulated with LPS in situ for 24?h, and mRNA was isolated to assess markers associated with inflammation and eicosanoid production. Culture media were collected to assess PGE2 secretion. Oxidative burst in macrophages was measured by: 1) oxygen consumption and extracellular acidification (via Seahorse), 2) cytoplasmic oxidation and 3) nitric oxide production following 4, 18, and 24?h of LPS stimulation. Results:Concentration of ARA (% of fatty acids, w/w) in macrophages from pigs fed LC n-6 was 86% higher than CON and 18% lower in pigs fed LC n-3 (P?

SUBMITTER: Walter KR 

PROVIDER: S-EPMC6376662 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature