Associations of maternal blood metal concentrations with plasma eicosanoids among pregnant women in Puerto Rico.

BACKGROUND/AIM: Heavy metals are known to induce oxidative stress and inflammation, and the association between metal exposure and adverse birth outcomes is well established. However, there lacks research on biomarker profiles linking metal exposures and adverse birth outcomes. Eicosanoids are lipid molecules that regulate inflammation in the body, and there is growing evidence that suggests associations between plasma eicosanoids and pregnancy outcomes. Eicosanoids may aid our understanding of etiologic birth pathways. Here, we assessed associations between maternal blood metal concentrations with eicosanoid profiles among 654 pregnant women in the Puerto Rico PROTECT birth cohort. METHODS: We measured concentrations of 11 metals in whole blood collected at median 18 and 26 weeks of pregnancy, and eicosanoid profiles measured in plasma collected at median 26 weeks. Multivariable linear models were used to regress eicosanoids on metals concentrations. Effect modification by infant sex was explored using interaction terms. RESULTS: A total of 55 eicosanoids were profiled. Notably, 12-oxoeicosatetraenoic acid (12-oxoETE) and 15-oxoeicosatetraenoic acid (15-oxoETE), both of which exert inflammatory activities, had the greatest number of significant associations with metal concentrations. These eicosanoids were associated with increased concentrations of Cu, Mn, and Zn, and decreased concentrations of Cd, Co, Ni, and Pb, with the strongest effect sizes observed for 12-oxoETE and Pb (ß:-33.5,95 %CI:-42.9,-22.6) and 15-oxoETE and Sn (ß:43.2,95 %CI:11.4,84.1). Also, we observed differences in metals-eicosanoid associations by infant sex. Particularly, Cs and Mn had the most infant sex-specific significant associations with eicosanoids, which were primarily driven by female fetuses. All significant sex-specific associations with Cs were inverse among females, while significant sex-specific associations with Mn among females were positive within the cyclooxygenase group but inverse among the lipoxygenase group. CONCLUSION: Certain metals were significantly associated with eicosanoids that are responsible for regulating inflammatory responses. Eicosanoid-metal associations may suggest a role for eicosanoids in mediating metal-induced adverse birth outcomes.

Genetic analyses of circulating PUFA-derived mediators identifies heritable dihydroxyeicosatrienoic acid species.

Estimates of heritability are the first step in identifying a trait with substantial variation due to genetic factors. Large-scale genetic analyses can identify the DNA variants that influence the levels of circulating lipid species and the statistical technique Mendelian randomisation can use these DNA variants to address potential causality of these lipids in disease. We estimated the heritability of plasma eicosanoids, octadecanoids and docosanoids to identify those lipid species with substantial heritability. We analysed plasma lipid mediators in 31 White British families (196 participants) ascertained for high blood pressure and deeply clinically and biochemically phenotyped over a 25-year period. We found that the dihydroxyeicosatrienoic acid (DHET) species, 11,12-DHET and 14,15-DHET, products of arachidonic acid metabolism by cytochrome P450 (CYP) monooxygenase and soluble epoxide hydrolase (sEH), exhibited substantial heritability (h2 = 33%-37%; Padj<0.05). Identification of these two heritable bioactive lipid species allows for future large-scale, targeted, lipidomics-genomics analyses to address causality in cardiovascular and other diseases.

Acute severe SARS COVID-19 patients produce pro-resolving lipids mediators and eicosanoids.

OBJECTIVE: This study aimed to evaluate the eicosanoid and pro resolutive parameters in SARS COVID-19 patients with the severe acute respiratory syndrome. PATIENTS AND METHODS: Fourteen male patients with an acute respiratory syndrome caused by SARS COVID-19 and four healthy controls were evaluated by measuring the following parameters in plasma: Polyunsaturated fatty acids: EPA, DHA, ARA, and DPA. Specialized Pro-resolving mediators (SPMs) (including monohydroxy-containing precursors 17-HDHA, 18-HEPE, 14-HDHA) resolvins, maresins, protectins, and lipoxins. The eicosanoids group included prostaglandins, thromboxanes, and leukotrienes. RESULTS: Plasma from COVID-19 patients presented higher amounts of pro-inflammatory and pro-thrombotic lipid mediators as compared to healthy subjects (65.7 pg/ml vs. 10.2 pg/ml), including thromboxane (2142.6 pg/ml vs. 10.4 pg/ml), and the ratio between total plasma pro-inflammatory mediators versus total SPM's was 13.2 to 0,4, respectively. CONCLUSIONS: A clear disbalance favoring the pro-inflammatory axis is described, showing the need to perform future clinical interventions in these patients using SPM's or monohydroxylated lipid mediators derivates from fatty acids.

Effect of n-3 long-chain polyunsaturated fatty acid intake on the eicosanoid profile in individuals with obesity and overweight: a systematic review and meta-analysis of clinical trials.

Dietary n-3 polyunsaturated fatty acids (PUFAs) present beneficial effects on counteracting inflammation status, displaying a critical anti-inflammatory role and maintaining physiological homeostasis in obesity. The primary objective of this systematic review was to evaluate the effect of n-3 PUFAs intake on the eicosanoid profile of people with obesity and overweight. The search strategy on Embase, Scopus, PubMed, Web of Science, Cochrane Library, Google Scholar and ProQuest was undertaken until November 2019 and updated January 2021. The effect size of n-3 PUFAs on prostaglandins was estimated by Glass's, type 1 in a random-effect model for the meta-analysis. Seven clinical trials met the eligible criteria and a total of 610 subjects were included in this systematic review, and four of seven studies were included in meta-analysis. The intake of n-3 PUFAs promoted an overall reduction in serum pro-inflammatory eicosanoids. Additionally, n-3 PUFAs intake significantly decreased the arachidonic acid COX-derived PG eicosanoid group levels (Glass's Δ -0⋅35; CI -0⋅62, -0⋅07, I 2 31⋅48). Subgroup analyses showed a higher effect on periods up to 8 weeks (Glass's Δ -0⋅51; CI -0⋅76, -0⋅27) and doses higher than 0⋅5 g of n-3 PUFAs (Glass's Δ -0⋅46; CI -0⋅72, -0⋅27). Dietary n-3 PUFAs intake contributes to reduce pro-inflammatory eicosanoids of people with obesity and overweight. Subgroup's analysis showed that n-3 PUFAs can reduce the overall arachidonic acid COX-derived PG when adequate dose and period are matched.

Changes in Phospholipid/Ceramide Profiles and Eicosanoid Levels in the Plasma of Rats Irradiated with UV Rays and Treated Topically with Cannabidiol.

Chronic UV radiation causes oxidative stress and inflammation of skin and blood cells. Therefore, in this study, we assessed the effects of cannabidiol (CBD), a natural phytocannabinoid with antioxidant and anti-inflammatory properties, on the phospholipid (PL) and ceramide (CER) profiles in the plasma of nude rats irradiated with UVA/UVB and treated topically with CBD. The results obtained showed that UVA/UVB radiation increased the levels of phosphatidylcholines, lysophospholipids, and eicosanoids (PGE2, TxB2), while downregulation of sphingomyelins led to an increase in CER[NS] and CER[NDS]. Topical application of CBD to the skin of control rats significantly upregulated plasma ether-linked phosphatidylethanolamines (PEo) and ceramides. However, CBD administered to rats irradiated with UVA/UVB promoted further upregulation of CER and PEo and led to significant downregulation of lysophospholipids. This was accompanied by the anti-inflammatory effect of CBD, manifested by a reduction in the levels of proinflammatory PGE2 and TxB2 and a dramatic increase in the level of anti-inflammatory LPXA4. It can therefore be suggested that topical application of CBD to the skin of rats exposed to UVA/UVB radiation prevents changes in plasma phospholipid profile resulting in a reduction of inflammation by reducing the level of LPE and LPC species and increasing antioxidant capacity due to upregulation of PEo species.

Could metabolomics drive the fate of COVID-19 pandemic? A narrative review on lights and shadows.

Human Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2) infection activates a complex interaction host/virus, leading to the reprogramming of the host metabolism aimed at the energy supply for viral replication. Alterations of the host metabolic homeostasis strongly influence the immune response to SARS-CoV-2, forming the basis of a wide range of outcomes, from the asymptomatic infection to the onset of COVID-19 and up to life-threatening acute respiratory distress syndrome, vascular dysfunction, multiple organ failure, and death. Deciphering the molecular mechanisms associated with the individual susceptibility to SARS-CoV-2 infection calls for a system biology approach; this strategy can address multiple goals, including which patients will respond effectively to the therapeutic treatment. The power of metabolomics lies in the ability to recognize endogenous and exogenous metabolites within a biological sample, measuring their concentration, and identifying perturbations of biochemical pathways associated with qualitative and quantitative metabolic changes. Over the last year, a limited number of metabolomics- and lipidomics-based clinical studies in COVID-19 patients have been published and are discussed in this review. Remarkable alterations in the lipid and amino acid metabolism depict the molecular phenotype of subjects infected by SARS-CoV-2; notably, structural and functional data on the lipids-virus interaction may open new perspectives on targeted therapeutic interventions. Several limitations affect most metabolomics-based studies, slowing the routine application of metabolomics. However, moving metabolomics from bench to bedside cannot imply the mere determination of a given metabolite panel; rather, slotting metabolomics into clinical practice requires the conversion of metabolic patient-specific data into actionable clinical applications.

Metabolomics in Severe Aortic Stenosis Reveals Intermediates of Nitric Oxide Synthesis as Most Distinctive Markers.

BACKGROUND: Calcific aortic valve disease (CAVD) is a rapidly growing global health problem with an estimated 12.6 million cases globally in 2017 and a 112% increase of deaths since 1990 due to aging and population growth. CAVD may develop into aortic stenosis (AS) by progressive narrowing of the aortic valve. AS is underdiagnosed, and if treatment by aortic valve replacement (AVR) is delayed, this leads to poor recovery of cardiac function, absence of symptomatic improvement and marked increase of mortality. Considering the current limitations to define the stage of AS-induced cardiac remodeling, there is need for a novel method to aid in the diagnosis of AS and timing of intervention, which may be found in metabolomics profiling of patients. METHODS: Serum samples of nine healthy controls and 10 AS patients before and after AVR were analyzed by untargeted mass spectrometry. Multivariate modeling was performed to determine a metabolic profile of 30 serum metabolites which distinguishes AS patients from controls. Human cardiac microvascular endothelial cells (CMECs) were incubated with serum of the AS patients and then stained for ICAM-1 with Western Blot to analyze the effect of AS patient serum on endothelial cell activation. RESULTS: The top 30 metabolic profile strongly distinguishes AS patients from healthy controls and includes 17 metabolites related to nitric oxide metabolism and 12 metabolites related to inflammation, in line with the known pathomechanism for calcific aortic valve disease. Nine metabolites correlate strongly with left ventricular mass, of which three show reversal back to control values after AVR. Western blot analysis of CMECs incubated with AS patient sera shows a significant reduction (14%) in ICAM-1 in AS samples taken after AVR compared to AS patient sera before AVR. CONCLUSION: Our study defined a top 30 metabolic profile with biological and clinical relevance, which may be used as blood biomarker to identify AS patients in need of cardiac surgery. Future studies are warranted in patients with mild-to-moderate AS to determine if these metabolites reflect disease severity and can be used to identify AS patients in need of cardiac surgery.

Pemafibrate, A Novel Selective Peroxisome Proliferator-Activated Receptor α Modulator, Reduces Plasma Eicosanoid Levels and Ameliorates Endothelial Dysfunction in Diabetic Mice.

AIMS: Various pathological processes related to diabetes cause endothelial dysfunction. Eicosanoids derived from arachidonic acid (AA) have roles in vascular regulation. Fibrates have recently been shown to attenuate vascular complications in diabetics. Here we examined the effects of pemafibrate, a selective peroxisome proliferator-activated receptor α modulator, on plasma eicosanoid levels and endothelial function in diabetic mice. METHODS: Diabetes was induced in 7-week-old male wild-type mice by a single injection of streptozotocin (150 mg/kg). Pemafibrate (0.3 mg/kg/day) was administered orally for 3 weeks. Untreated mice received vehicle. Circulating levels of eicosanoids and free fatty acids were measured using both gas and liquid chromatography-mass spectrometry. Endothelium-dependent and endothelium-independent vascular responses to acetylcholine and sodium nitroprusside, respectively, were analyzed. RESULTS: Pemafibrate reduced both triglyceride and non-high-density lipoprotein-cholesterol levels (P＜0.01), without affecting body weight. It also decreased circulating levels of AA (P＜0.001), thromboxane B2 (P＜0.001), prostaglandin E2, leukotriene B4 (P＜0.05), and 5-hydroxyeicosatetraenoic acid (P＜0.001), all of which were elevated by the induction of diabetes. In contrast, the plasma levels of 15-deoxy-Δ12,14-prostaglandin J2, which declined following diabetes induction, remained unaffected by pemafibrate treatment. In diabetic mice, pemafibrate decreased palmitic acid (PA) and stearic acid concentrations (P＜0.05). Diabetes induction impaired endothelial function, whereas pemafibrate ameliorated it (P＜0.001). The results of ex vivo experiments indicated that eicosanoids or PA impaired endothelial function. CONCLUSION: Pemafibrate diminished the levels of vasoconstrictive eicosanoids and free fatty acids accompanied by a reduction of triglyceride. These effects may be associated with the improvement of endothelial function by pemafibrate in diabetic mice.

Effects of angiotensin II receptor blockers on serum levels of epoxyeicosatrienoic acids and dihydroxyeicosatrienoic acids in patients admitted to a cardiovascular center.

PURPOSE: Several clinical studies have demonstrated that angiotensin-converting enzyme inhibitors, but not angiotensin II receptor blockers (ARBs), reduce the risk of non-fatal myocardial infarction and cardiovascular mortality. We found that ARBs inhibited the activity of various cytochrome enzymes in arachidonic acid metabolism, resulting in decreased in vitro production of epoxyeicosatrienoic acids (EETs), which exhibit vasodilation and anti-inflammatory effects, and their subsequent metabolites, dihydroxyeicosatrienoic acids (DHETs). The present study examined the effects of ARBs on serum levels of EETs and DHETs in patients admitted to a cardiovascular center. METHODS: A total of 223 patients were enrolled, of which 107 were exposed to ARBs in this study. ARB-free individuals were defined as the control group (n = 116). Serum levels of EETs and DHETs were measured by liquid chromatography-tandem mass spectrometry. Multiple linear regression analyses were carried out to identify covariates for total serum levels of EETs and DHETs. RESULTS: A significant negative association was observed between ARB use and serum EET and DHET levels (p = 0.034), whereas a significant positive association was observed between the estimated glomerular filtration rate (eGFR) and serum EET and DHET levels (p = 0.007). The median serum total EET and DHET level in the ARB group tended to become lower than that in the control group, although the difference was not significant. CONCLUSION: ARB use and eGFR were significantly associated with total serum levels of EETs and DHETs. Our results suggest that ARBs could affect the concentration of EETs in vivo.

Changes in erythrocyte membrane epoxyeicosatrienoic, dihydroxyeicosatrienoic, and hydroxyeicosatetraenoic acids during pregnancy.

AIMS: Pregnancy is associated with numerous changes in physiological and metabolic processes to ensure successful progression to full term. One such change is the alteration of arachidonic acid (AA) metabolism and formation of eicosanoids. This study explores the changes in AA metabolites formed through the cytochrome P450 mediated pathway to epoxyeicosatrienoic (EET), dihydroxyeicosatrienoic (DHET), and hydroxyeicosatetraenoic (HETE) acids which have been implicated in blood pressure regulation and inflammatory responses that are important for a healthy pregnancy. MAIN METHODS: The study determines circulating levels of EETs, DHETs and HETEs extracted from erythrocyte membranes and measured by mass spectroscopy during the progression of a normal pregnancy. Blood samples, from 25 women, were collected at three time points including 25-28 weeks gestation, 28-32 weeks gestation, and the non-pregnant control at 3-4 months postpartum. KEY FINDINGS: Results demonstrate that healthy pregnancy is associated with significant increases in 8,9-DHET, 11,12-DHET and 14,15-DHET and a decrease in trans 8,9-EET during 28-32 weeks gestation compared to 3-4 months postpartum. These differences are likely due to several mechanisms including an increase in soluble epoxide hydrolase activity, a decrease in glutathione conjugation, and altered cytochrome P450 enzyme expression and/or activity that occurs during pregnancy. SIGNIFICANCE: Metabolism of AA through the cytochrome P450 pathway generates physiologically important eicosanoids that could play an important role in the progression of a healthy pregnancy. Establishing the changes that occur during normal pregnancy may, in the future, help in early detection of pregnancy complications including preeclampsia.

Cellular interactions in aspirin-exacerbated respiratory disease.

PURPOSE OF REVIEW: The purpose of this review is to summarize the complex cellular interactions of aspirin-exacerbated respiratory disease (AERD) and how these interactions promote pathogenic mechanisms of AERD. RECENT FINDINGS: In addition to characteristic changes in eicosanoid levels, recent studies have identified increases in alarmin cytokines (IL-33, thymic stromal lymphopoietin) as well as activated innate lymphoid and plasma cell populations in samples from AERD patients. SUMMARY: Patients with AERD typically demonstrate high levels of proinflammatory eicosanoids including cysteinyl leukotrienes (CysLTs) and prostaglandin D2 (PGD2) and hyporesponsiveness to prostaglandin E2 (PGE2). CysLTs are released by mast cells, eosinophils, and adherent platelets and promote epithelial release of IL-33, which activates mast cells and group 2 innate lymphoid cells (ILC2s) in concert with CysLTs. TSLP induces PGD2 release from mast cells which activates and recruits eosinophils, basophils, Th2 cells, and ILC2s via CRTH2. In turn, ILC2s and other cell types produce Th2 cytokines IL-4, IL-5, and IL-13 that, along with CysLTs and PGD2, promote bronchoconstriction, eosinophilic tissue inflammation, and mucus production.

Cutting Edge: Severe SARS-CoV-2 Infection in Humans Is Defined by a Shift in the Serum Lipidome, Resulting in Dysregulation of Eicosanoid Immune Mediators.

The COVID-19 pandemic has affected more than 20 million people worldwide, with mortality exceeding 800,000 patients. Risk factors associated with severe disease and mortality include advanced age, hypertension, diabetes, and obesity. Each of these risk factors pathologically disrupts the lipidome, including immunomodulatory eicosanoid and docosanoid lipid mediators (LMs). We hypothesized that dysregulation of LMs may be a defining feature of the severity of COVID-19. By examining LMs and polyunsaturated fatty acid precursor lipids in serum from hospitalized COVID-19 patients, we demonstrate that moderate and severe disease are separated by specific differences in abundance of immune-regulatory and proinflammatory LMs. This difference in LM balance corresponded with decreased LM products of ALOX12 and COX2 and an increase LMs products of ALOX5 and cytochrome p450. Given the important immune-regulatory role of LMs, these data provide mechanistic insight into an immuno-lipidomic imbalance in severe COVID-19.

Omega-3 polyunsaturated fatty acid supplementation improves lipid metabolism and endothelial function by providing a beneficial eicosanoid-pattern in patients with acute myocardial infarction: A randomized, controlled trial.

BACKGROUND & AIMS: Omega-3 polyunsaturated fatty acid (ω-3 PUFA) have been reported to have beneficial cardiovascular effects, but its mechanism of protection against acute myocardial infarction (AMI) who are under guideline-based therapy is not fully understood. Here, we used a metabolomic approach to systematically analyze the eicosanoid metabolites induced by ω-3 PUFA supplementation and investigated the underlying mechanisms. METHODS: Participants with AMI after successful percutaneous coronary intervention were randomized to 3 months of 2 g daily ω-3 PUFA and guideline-adjusted therapy (n = 30, ω-3 therapy) or guideline-adjusted therapy alone (n = 30, Usual therapy). Functional PUFA-derived eicosanoids in plasma were profiled by metabolomics. Clinical and laboratory tests were obtained before and 3 months after baseline and after the study therapy. RESULTS: By intent-to-treat analysis, the content of 11-HDoHE, 20-HDoHE and 16,17-EDP and that of epoxyeicosatetraenoic acids (EEQs), derived from docosahexaenoic acid and eicosapentaenoic acid, respectively, were significantly higher with ω-3 group than Usual therapy, whereas that of prostaglandin J2 (PGJ2) and leukotriene B4, derived from arachidonic acid, was significantly decreased. As compared with Usual therapy, ω-3 PUFA therapy significantly reduced levels of triglycerides (-6.3%, P < 0.05), apolipoprotein B (-4.9%, P < 0.05) and lipoprotein(a) (-37.0%, P < 0.05) and increased nitric oxide level (62.2%, P < 0.05). In addition, the levels of these variables were positively correlated with change in 16,17-EDP and EEQs content but negatively with change in PGJ2 content. CONCLUSIONS: ω-3 PUFA supplementation may improve lipid metabolism and endothelial function possibly by affecting eicosanoid metabolic status at a systemic level during convalescent healing after AMI. CLINICAL TRIAL REGISTRATION: URL: http://www.chictr.org.cn. Unique identifier: ChiCTR1900025859.

Free Fatty Acids and Their Inflammatory Derivatives Affect BDNF in Stroke Patients.

OBJECTIVE: The neurotrophin brain-derived neurotrophic factor (BDNF) affects poststroke functional outcome, neurogenesis, neuroprotection, and neuroplasticity. Its level is related to the diet and nutritional status, and more specifically, it is free fatty acids (FFAs) and eicosanoids that can have an impact on the BDNF level. The aim of this study was to analyze the potential impact of FFAs and eicosanoids on the BDNF level in stroke patients. Material and Methods. Seventy-three ischemic stroke patients were prospectively enrolled in the study. Laboratory tests were performed in all subjects, including the levels of FFAs, eicosanoids, and BDNF. FFAs and inflammatory metabolites were determined by gas chromatography and liquid chromatography, while BDNF was evaluated by the immune-enzymatic method (ELISA). RESULTS: The plasma level of BDNF negatively correlated with C22:1n9 13 erucic acid, C18:3n3 linolenic acid (ALA), and lipoxin A4 15-epi-LxA4. A direct association was observed in relation to BDNF and C16:1 palmitoleic acid and C20:3n6 eicosatrienoic acid (dihomo-gamma-linolenic acid (DGLA)). CONCLUSIONS: Saturated fatty acids and omega-3 and omega-9 erucic acids can affect signaling in the BDNF synthesis resulting in the decrease in BDNF. There is a beneficial effect of DGLA on the BDNF level, while the effect of ALA on BDNF can be inhibitory. Specialized proresolving lipid mediators can play a role in the BDNF metabolism. BDNF can interact with inflammation as the risk factor in the cardiovascular disorders, including stroke.

The relationship between specialized pro-resolving lipid mediators, morbid obesity and weight loss after bariatric surgery.

Obesity and diabetes are associated with chronic inflammation. Specialized pro-resolving lipid mediators (SPMs)-resolvins (Rv), protectins (PD) and maresins (MaR)-actively resolve inflammation. Bariatric surgery achieves remission of diabetes, but mechanisms are unclear. We measured SPMs and proinflammatory eicosanoid levels using liquid chromatography-tandem mass spectrometry in 29 morbidly obese subjects (13 with diabetes) and 15 nondiabetic, mildly obese subjects. Compared to the mildly obese, the morbidly obese had higher levels of SPMs-RvD3, RvD4 and PD1-and white blood cells (WBC) and platelets. Post-surgery, SPM and platelet levels decreased in morbidly obese nondiabetic subjects but not in diabetic subjects, suggesting continued inflammation. Despite similar weight reductions 1 year after surgery (44.6% vs. 46.6%), 8 diabetes remitters had significant reductions in WBC and platelet counts whereas five non-remitters did not. Remitters had a 58.2% decrease (p = 0.03) in 14-HDHA, a maresin pathway marker; non-remitters had an 875.7% increase in 14-HDHA but a 36.9% decrease in MaR1 to a median of 0. In conclusion, higher levels of RvD3, PD1 and their pathway marker, 17-HDHA, are markers of leukocyte activation and inflammation in morbid obesity and diabetes and diminish with weight loss in nondiabetic but not diabetic subjects, possibly representing sustained inflammation in the latter. Lack of diabetes remission after surgically-induced weight loss may be associated with reduced ability to produce MaR1 and sustained inflammation.

Changes in PUFA and eicosanoid metabolism during/after apnea diving: a prospective single-center study.

Background: The popularity of apneic diving is continually growing. As apnea diving substantially burdens the cardiovascular system, special focus is warranted. Regarding inflammation processes and associated inflammatory-related diseases (e.g., cardiovascular diseases), eicosanoids play an important role. This study aims to investigate polyunsaturated fatty acids (PUFAs) and eicosanoids in voluntary apnea divers, and so to further improve understanding of pathophysiological processes focusing on proinflammatory effects of temporarily hypercapnic hypoxia.. Methods: The concentration of PUFAs and eicosanoids were investigated in EDTA plasma in apnea divers (n=10) before and immediately after apnea, 0.5 hour and four hours later, applying liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results: Mean age was 41±10 years, and divers performed a mean breath-hold time of 317±111 seconds. PUFAs, eicosanoids and related lipids could be classified in four different kinetical reaction groups following apnea. The first group (e.g., Ω-6 and Ω-3-PUFAs) showed an immediate concentration increase followed by a decrease below baseline four hours after apnea. The second group (e.g., thromboxane B2) showed a slower increase, with its maximum concentration 0.5 hour post-apnea followed by a decrease four hours post-apnea. Group 3 (9- and 13-hydroxyoctadecadienoic acid) is characterized by two concentration increase peaks directly after apnea and four hours afterward compared to baseline. Group 4 (e.g., prostaglandin D2) shows no clear response. Conclusion: Changes in the PUFA metabolism after even a single apnea revealed different kinetics of pro- and anti-inflammatory regulations and changes for oxidative stress levels. Due to the importance of these mediators, apnea diving should be evaluated carefully and be performed only with great caution against the background of cardiovascular diseases and inflammation processes.

Eicosanoid Inflammatory Mediators Are Robustly Associated With Blood Pressure in the General Population.

Background Epidemiological and animal studies have associated systemic inflammation with blood pressure (BP). However, the mechanistic factors linking inflammation and BP remain unknown. Fatty acid-derived eicosanoids serve as mediators of inflammation and have been suggested to regulate renal vascular tone, peripheral resistance, renin-angiotensin system, and endothelial function. We hypothesize that specific proinflammatory and anti-inflammatory eicosanoids are linked with BP. Methods and Results We studied a population sample of 8099 FINRISK 2002 participants randomly drawn from the Finnish population register (53% women; mean age, 48±13 years) and, for external validation, a sample of 2859 FHS (Framingham Heart Study) Offspring study participants (55% women; mean age, 66±9 years). Using nontargeted liquid chromatography-mass spectrometry, we profiled 545 distinct high-quality eicosanoids and related oxylipin mediators in plasma. Adjusting for conventional hypertension risk factors, we observed 187 (34%) metabolites that were significantly associated with systolic BP (P

Longitudinal profiles of plasma eicosanoids during pregnancy and size for gestational age at delivery: A nested case-control study.

BACKGROUND: Inflammation during pregnancy is hypothesized to influence fetal growth. Eicosanoids, an important class of lipid mediators derived from polyunsaturated fatty acids, can act as both direct influences and biomarkers of inflammation through a variety of biological pathways. However, quantifying these distinct inflammatory pathways has proven difficult. We aimed to characterize a comprehensive panel of plasma eicosanoids longitudinally across gestation in pregnant women and to determine whether levels differed by infant size at delivery. METHODS AND FINDINGS: Our data come from a case-control study of 90 pregnant women nested within the LIFECODES prospective birth cohort study conducted at Brigham and Women's Hospital in Boston, Massachusetts. This study included 31 women who delivered small for gestational age (SGA) babies (SGA, ≤10th percentile), 28 who delivered large for gestational age (LGA) babies (≥90th percentile), and 31 who delivered appropriate for gestational age (AGA) babies (controls, >10th to <90th percentile). All deliveries occurred between 2010 and 2017. Most participants were in their early 30s (median age: 33 years), of white (60%) or black (20%) race/ethnicity, and of normal pre-pregnancy BMI (median BMI: 23.5 kg/m2). Women provided non-fasting plasma samples during 3 prenatal study visits (at median 11, 25, and 35 weeks gestation) and were analyzed for a panel of eicosanoids. Eicosanoids were grouped by biosynthetic pathway, defined by (1) the fatty acid precursor, including linoleic acid (LA), arachidonic acid (AA), docosahexaenoic acid (DHA), or eicosapentaenoic acid (EPA), and (2) the enzyme group, including cyclooxygenase (COX), lipoxygenase (LOX), or cytochrome P450 (CYP). Additionally, the concentrations of the 4 fatty acids (LA, AA, DHA, and EPA) were measured in maternal plasma. Analytes represent lipids from non-esterified plasma. We examined correlations among eicosanoids and trajectories across pregnancy. Differences in longitudinal concentrations between case groups were examined using Bayesian linear mixed effects models, which included participant-specific random intercepts and penalized splines on gestational age. Results showed maternal plasma levels of eicosanoids and fatty acids generally followed U-shaped curve patterns across gestation. Bayesian models showed that associations between eicosanoids and case status varied by biosynthetic pathway. Eicosanoids derived from AA via the CYP and LOX biosynthetic pathways were positively associated with SGA. The adjusted mean concentration of 12-HETE, a LOX pathway product, was 56.2% higher (95% credible interval 6.6%, 119.1%) among SGA cases compared to AGA controls. Eicosanoid associations with LGA were mostly null, but negative associations were observed with eicosanoids derived from AA by LOX enzymes. The fatty acid precursors had estimated mean concentrations 41%-97% higher among SGA cases and 33%-39% lower among LGA cases compared to controls. Primary limitations of the study included the inability to explore the potential periods of susceptibility of eicosanoids on infant size due to limited sample size, along with the use of infant size at delivery instead of longitudinal ultrasound measures to estimate fetal growth. CONCLUSIONS: In this nested case-control study, we found that eicosanoids and fatty acids systematically change in maternal plasma over pregnancy. Eicosanoids from specific inflammation-related pathways were higher in mothers of SGA cases and mostly similar in mothers of LGA cases compared to controls. These findings can provide deeper insight into etiologic mechanisms of abnormal fetal growth outcomes.

Quantitative profiling of eicosanoids derived from n-6 and n-3 polyunsaturated fatty acids by twin derivatization strategy combined with LC-MS/MS in patients with type 2 diabetes mellitus.

Eicosanoids derived from n-6 and n-3 polyunsaturated fatty acids (PUFAs), serving as important signaling molecules, are implicated in many physiological and pathological processes, including Type 2 diabetes mellitus (T2DM). However, the quantification of endogenous eicosanoids is challenged by high structural similarity, low abundance in biological sample and poor electrospray ionization efficiency. In the current study, a sensitive and accurate liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to quantify 65 eicosanoids derived from n-6 and n-3 PUFAs in plasma samples using twin derivatization strategy with a pair of reagents, 5-(dimethylamino) naphthalene-1-sulfonyl piperazine (Dns-PP) and (diethylamino) naphthalene-1-sulfonyl piperazine (Dens-PP). Dns-PP-derivatized plasma sample was mixed with the equal volume of Dens-PP-derivatized eicosanoid internal standards for LC-MS/MS analysis in multiple reaction monitoring (MRM) mode. After Dns-PP derivatization, the ionization efficiency and separation performance were substantially improved, resulting in the enhanced sensitivity by 446- to 1009-folds compared to intact eicosanoids. The quantitative accuracy determined by twin derivatization method was found to be comparable with stable isotope labeled internal standards (SIL-IS) method. The newly proposed method was successfully employed to quantify the target eicosanoids in plasma samples from healthy controls and the patients with T2DM. N-6 PUFA-derived eicosanoids, PGF2α, PGD2, PGE2, PGA2, PGB2, 20-HETE and LTC4, significantly increased in plasma sample of T2DM patients. Oppositely, n-3 PUFA-derived eicosanoids, RvE1, 12(S)-HEPE and RvD1, remarkably decreased. Spearman's correlation analysis indicated the strong correlations between these highlighted eicosanoids and clinical parameters of T2DM. Collectively, the sensitive and reliable eicosanoid quantification method may facilitate to elucidate the characteristics of eicosanoid metabolism and understand the role of eicosanoids in the pathogenesis of T2DM and other diseases.