Plasma Lipid Profiling Identifies Phosphatidylcholine 34:3 and Triglyceride 52:3 as Potential Markers Associated with Disease Severity and Oxidative Status in Chronic Obstructive Pulmonary Disease.

ABSTRACT

PURPOSE: To identify plasma alterations in lipid species in patients with chronic obstructive pulmonary disease (COPD), as well as, relationships with smoking status, oxidative and inflammatory markers. METHODS: Plasma was obtained from 100 patients with COPD and 120 healthy controls. Pulmonary function was assessed by plethysmography. Serum levels of IL-6 and TNF-α were determined by ELISA. Oxidative stress parameters were measured using standard methods. Lipids were extracted then analyzed by Matrix-Assisted Laser Desorption and Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF-TOF-MS). RESULTS: More than 40 lipid compounds were identified within plasma samples. Among these 19 lipid species including plasmalogens (PC O-), phosphatidylcholines (PC), and triglycerides (TG) were significantly altered in COPD. A decreased expression of PC O- (361, 362, 363, 364, 384, 385) species was found in patients with different severities compared to healthy controls. There was also a decrease in PC (343, 360, 364, 365, 406, 407) species in COPD patients. PC (343) levels were positively correlated with disease progression and pulmonary function decline (forced expiratory volume in 1 s (FEV1)) (r = 0.84, p < 0.001) and inversely correlated with thiobarbituric acid-reactive substances (TBARS) (r = - 0.77, p < 0.001). TG (500, 501, 521, 522, 523, 524, 544) species were altered in COPD patients and in those with advanced disease stages. Significant correlations between FEV1, TBARS, peroxynitrite, and TG (523) were found among COPD patients (r = - 0.69; r = 0.86; r = 0.77, p < 0.001, respectively). CONCLUSION: PC (343) and TG (523) could be potential lipid signatures of COPD that correlate with altered pulmonary function and oxidative status.