Linoleic acid-derived lipid mediators increase in a female-dominated subphenotype of COPD

Abstract

Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality; however, the role of inflammatory mediators in its pathobiology remains unclear. The aim of this study was to investigate the influence of gender in COPD on lipid mediator levels.Bronchoalveolar lavage fluid (BALF) and serum were obtained from healthy never-smokers, smokers and COPD patients (Global Initiative for Chronic Obstructive Lung Disease stage I-II/A-B) (n=114). 94 lipid mediators derived from the cytochrome-P450, lipoxygenase, and cyclooxygenase pathways were analysed by liquid chromatography-mass spectrometry.Multivariate modelling identified a 9-lipid panel in BALF that classified female smokers with COPD from healthy female smokers (p=6×10(-6)). No differences were observed for the corresponding male population (p=1.0). These findings were replicated in an independent cohort with 92% accuracy (p=0.005). The strongest drivers were the cytochrome P450-derived epoxide products of linoleic acid (leukotoxins) and their corresponding soluble epoxide hydrolase (sEH)-derived products (leukotoxin-diols). These species correlated with lung function (r=0.87; p=0.0009) and mRNA levels of enzymes putatively involved in their biosynthesis (r=0.96; p=0.003). Leukotoxin levels correlated with goblet cell abundance (r=0.72; p=0.028).These findings suggest a mechanism by which goblet cell-associated cytochrome-P450 and sEH activity produce elevated leukotoxin-diol levels, which play a putative role in the clinical manifestations of COPD in a female-dominated disease sub-phenotype.

GM‐CSF– and M‐CSF–primed macrophages present similar resolving but distinct inflammatory lipid mediator signatures

“…The column was then washed with 95% of solvent B for 3 min and equilibrated to initial conditions. Detailed multiple reaction monitoring transitions and chromatographic retention times are reported in Balgoma et al (17), except for the Cys-LTs (Supplemental Table 3). …”

“…To the supernatants, 1.5 or 2 ml of citrate/phosphate buffer (0.1 and 0.2 mM, pH 5.6), respectively, were added, and solutions were spiked with an internal standard mixture. The calibration levels and internal standards are provided in Balgoma et al (17), except for the Cys-LTs (Supplemental Table 2). Lipid mediators were extracted using 3 ml/60 mg Evolute Express ABN solid-phase extraction (SPE) cartridges (Biotage, Uppsala, Sweden) on an Extrahera sample handling system (Biotage).…”

“…Separation was achieved with an Acquity UPLC BEH C18 (2.1 3 150 mm, 1.7 mm) (Waters). Chromatographic and MS conditions were used as previously described (17). For quantification of the CysLTs, a second injection of each sample was performed in positive electrospray ionization mode with the following chromatographic conditions: solvents A (water with 0.2% of formic acid) and B (acetonitrile/isopropanol 90:10, v/v + 0.2% formic acid) at a flow of 0.45 ml/min.…”

“…A previously published stable isotope dilution LC-MS/MS method was used for lipid mediator quantification (17), with slight modification to include the cysteinyl leukotrienes (Cys-LTs) LTC 4 , LTD 4 , and LTE 4 . Aliquots of conditioned cell culture medium (1 ml) or stopped cell incubates (0.5 ml) were centrifuged at 10,000 g for 10 min at 4°C.…”

New insights into the effects of onion consumption on lipid mediators using a diet-induced model of hypercholesterolemia

“…Extraction of oxylipins from plasma and liver homogenate was carried out as previously described [31] with minor modifications. Briefly, 10 µL of internal standards solution were spiked to 250 µL of plasma or 50 mg of liver tissue homogenate.…”