Temporal associations of plasma levels of the secreted phospholipase A2 family and mortality in severe COVID-19.

Previous research suggests that group IIA-secreted phospholipase A2 (sPLA2-IIA) plays a role in and predicts lethal COVID-19 disease. The current study reanalyzed a longitudinal proteomic data set to determine the temporal relationship between levels of several members of a family of sPLA2 isoforms and the severity of COVID-19 in 214 ICU patients. The levels of six secreted PLA2 isoforms, sPLA2-IIA, sPLA2-V, sPLA2-X, sPLA2-IB, sPLA2-IIC, and sPLA2-XVI, increased over the first 7 ICU days in those who succumbed to the disease but attenuated over the same time period in survivors. In contrast, a reversed pattern in sPLA2-IID and sPLA2-XIIB levels over 7 days suggests a protective role of these two isoforms. Furthermore, decision tree models demonstrated that sPLA2-IIA outperformed top-ranked cytokines and chemokines as a predictor of patient outcome. Taken together, proteomic analysis revealed temporal sPLA2 patterns that reflect the critical roles of sPLA2 isoforms in severe COVID-19 disease.

Secretory Phospholipase A2 Levels Are High in Women with Sickle Cell Disease and Menstruation-Induced Vaso-Occlusive Crises.

Menstruation-induced vaso-occlusive crisis (MIVOC) is a significant cause of morbidity in women with sickle cell disease (SCD). Secretory phospholipase A2 (sPLA2) is an inflammatory biomarker that is elevated in vaso-occlusive events such as acute chest syndrome (ACS), but its role in MIVOC is not previously studied. This study compared the serum level of sPLA2 among women with MIVOC and those without MIVOC. This is a comparative cross-sectional study. 354 women with SCD were screened for MIVOC using a structured questionnaire. sPLA2 levels were assayed using a standard ELISA while full blood counts were performed on an automated hematology analyzer. Data were analyzed using the SPSS software v26.0. Results were summarized as frequencies, percentages, and mean ± standard deviation. Variables were compared using the Student's t-test and Pearson's correlation. A p-value of <.05 was considered significant. The prevalence of MIVOC was 26.8%. Participants with MIVOC (n = 95) had significantly lower mean hemoglobin concentration (8.00 ± 2.03g/dL vs. 9.95 ± 4.15g/dL, p < .000), significantly higher mean platelets count (518.71 ± 84.58 × 109/L vs 322.21 ± 63.80 × 109/L, p < .000) and higher sPLA2 level (6.58 ± 1.94 IU vs 6.03 ± 0.42 IU, p = .008) compared to those without MIVOC (n = 95). Among participants with MIVOC, sPLA2 levels positively correlated with total white blood cell, absolute neutrophil, and lymphocyte counts. This study demonstrates that MIVOC is common among women with SCD and that the pathophysiology of MIVOC may have an inflammatory basis similar to that of ACS. The potential role of anti-inflammatory and antiplatelet agents in preventing and treating MIVOC may be explored.

The Role of Serum Albumin and Secretory Phospholipase A2 in Sepsis.

Sepsis is caused by a dysregulated host response to an infection that leads to cascading cell death and eventually organ failure. In this study, the role of inflammatory response serum secretory phospholipase A2 (sPLA2) and albumin in sepsis was investigated by determining the activities of the two proteins in serial serum samples collected on different days from patients with sepsis after enrollment in the permissive underfeeding versus standard enteral feeding protocols in an intensive care unit. Serum sPLA2 and albumin showed an inverse relationship with increasing sPLA2 activity and decreasing albumin membrane-binding activity in patients with evolving complications of sepsis. The activities of sPLA2 and albumin returned to normal values more rapidly in the permissive underfeeding group than in the standard enteral feeding group. The inverse sPLA2-albumin activity relationship suggests a complex interplay between these two proteins and a regulatory mechanism underlying cell membrane phospholipid homeostasis in sepsis. The decreased albumin-membrane binding activity in patients' serum was due to its fatty acid-binding sites occupied by pre-bound fatty acids that might alter albumin's structure, binding capacities, and essential functions. The sPLA2-albumin dual serum assays may be useful in determining whether nutritional intervention effectively supports the more rapid recovery of appropriate immune responses in critically ill patients with sepsis.

Carriers of the PCSK9 R46L Variant Are Characterized by an Antiatherogenic Lipoprotein Profile Assessed by Nuclear Magnetic Resonance Spectroscopy-Brief Report.

OBJECTIVE: Carriers of the PCSK9 (proprotein convertase subtilisin/kexin 9) R46L genetic variant (rs11591147) are characterized by low levels of low-density lipoprotein cholesterol and a decreased risk of cardiovascular disease. We studied the impact of the R46L variant on lipoprotein size and composition. APPROACH AND RESULTS: Lipoprotein size and composition were measured by nuclear magnetic resonance spectroscopy in 2373 participants of the EPIC (European Prospective Investigation into Cancer and Nutrition)-Norfolk study. After adjusting for age, sex, and cardiovascular disease status, carriers of the R46L variant (n=77) were characterized by lower concentrations of very low-density lipoprotein particles (85.8±26.2 versus 99.0±33.3 nmol/L; P<0.001), low-density lipoprotein particles (1479.7±396.8 versus 1662.9±458.3 nmol/L; P<0.001), and lipoprotein(a) (11.1 [7.2-28.6] versus 12.4 [6.7-29.1] mg/dL; P<0.001) compared with noncarriers. Total high-density lipoprotein particle and very low-density lipoprotein, low-density lipoprotein, and high-density lipoprotein particle sizes were comparable in carriers and noncarriers. Carriers were characterized by lower secretory phospholipase A2 (4.2±0.9 versus 4.6±1.3 nmol/mL/min; P=0.004) and lipoprotein-associated phospholipase A2 activity (47.5±14.1 versus 52.4±16.2 nmol/mL/min; P=0.02) compared with noncarriers. CONCLUSIONS: Results of this study suggest that carriers of the PCSK9 R46L genetic variant have lower very low-density lipoprotein and low-density lipoprotein particle concentrations, lower lipoprotein(a) levels, and lower secretory phospholipase A2 and lipoprotein-associated phospholipase A2 activity compared with noncarriers.

Probiotics and antimicrobial protein and peptide levels in preterm infants.

AIM: To characterise the secreted and inducible antimicrobial protein and peptide (APP) levels in a prospective cohort of preterm infants (<30 weeks gestational age) with or without Bifidobacterium breve M16V supplementation during the first month of life. METHODS: We analysed serial biosamples of infants who did (n = 13) or did not receive (n = 62) B. breve (3 × 109 cfu/day). Peripheral blood was obtained on days 1, 14 and 28, and infant stool prior to commencement of probiotic supplementation and on day 21. Levels of APP (bactericidal/permeability inducing protein (BPI), beta defensins 1 and 2, lactoferrin, human cathelicidin, secretory phospholipase A2) in plasma and stool were determined. Further, we characterised induced APP levels in whole blood cultured with live S. epidermidis or with agonists of Toll-like receptors 2/6 and 4. RESULTS: Stool, plasma and stimulated blood APP levels changed significantly during the first month of life. Supplementation with B. breve did not affect basal or stimulated APP levels except for a transient increase in inducible BPI. CONCLUSION: Supplementation with B. breve does not appear to act via modulation of systemic or enteric APP expression in preterm infants although small effects cannot be excluded. Further work with other probiotic preparations is warranted.

Comparison of lipid and lipid-associated cardiovascular risk marker changes after treatment with tocilizumab or adalimumab in patients with rheumatoid arthritis.

OBJECTIVE: Compare changes in lipids and lipid-associated cardiovascular (CV) risk markers in patients with rheumatoid arthritis (RA) treated with tocilizumab or adalimumab. METHODS: Post-hoc analysis was performed in patients with RA who received tocilizumab intravenously every 4 weeks or adalimumab subcutaneously every 2 weeks for 24 weeks in the ADACTA trial. Lipid and lipid-associated CV risk biomarkers, including high-density lipoprotein-associated serum amyloid-A (HDL-SAA), secretory phospholipase A2 IIA (sPLA2 IIA) and lipoprotein(a) (Lp(a)), were measured at baseline and at week 8. RESULTS: The study included 162 patients treated with tocilizumab and 162 patients treated with adalimumab; HDL-SAA and sPLA2 IIA were measured in a subpopulation of 87 and 97 patients, respectively. Greater increases in mean low-density lipoprotein cholesterol (LDL-C) (0.46 mmol/L (95% CI 0.30 to 0.62)), high-density lipoprotein cholesterol (HDL-C) (0.07 mmol/L (0.001 to 0.14)), total cholesterol (TC) (0.67 mmol/L (0.47 to 0.86)), triglycerides (0.24 mmol/L (0.10 to 0.38)) and TC:HDL ratio (0.27 (0.12 to 0.42)) occurred with tocilizumab from baseline to 8 weeks. HDL-SAA, sPLA2 IIA and Lp(a) decreased more with tocilizumab than adalimumab. Median changes from baseline to week 8 were -3.2 and -1.1 mg/L (p=0.0077) for HDL-SAA and -4.1 and -1.3 ng/mL (p<0.0001) for sPLA2 IIA; difference in adjusted means was -7.12 mg/dL (p<0.0001) for Lp(a). Similar results were observed in efficacy responders and non-responders per American College of Rheumatology and European League against Rheumatism criteria. CONCLUSION: LDL-C and HDL-C increased more with tocilizumab than adalimumab. HDL-SAA, sPLA2 IIA and Lp(a) decreased more with tocilizumab. Lipid change effects of interleukin-6 and tumour necrosis factor (TNF) inhibition, manifest by their net impact on lipids and lipoproteins, are not synonymous; the clinical significance is unclear and requires further study. TRIAL REGISTRATION NUMBER: NCT01119859.; post-results.

Secretory phospholipase A2 activity in blood serum: the challenge to sense.

Excess levels of secretory phospholipase A2 (sPLA2) is known to contribute to several inflammatory diseases including vascular inflammation correlating with coronary events in coronary artery disease. Thus a method to monitor sPLA2 activity in blood serum is urgently needed. Such method is still a challenge since existing fluorescent probes do not allow to monitor sPLA2 activity directly in blood serum. Here we analyze and overcome barriers in sPLA2 sensing methodology and report a fluorescent probe and a kinetic model of its hydrolysis by sPLA2. New probe is designed with a fluorophore and a quencher not interfering binding to the enzyme. At the same time phospholipid matrix bearing the probe promotes efficient initial quenching of the fluorophore. Kinetic model of probe hydrolysis takes into account signal change due to the side processes. The probe and the kinetic model applied together prove the concept that the activity of sPLA can be measured directly in blood serum.

Phospholipase A2 enzymes, high-dose atorvastatin, and prediction of ischemic events after acute coronary syndromes.

BACKGROUND: Secretory phospholipase A2 (sPLA(2)) and lipoprotein-associated phospholipase A2 (Lp-PLA(2)) are enzyme biomarkers of increased cardiovascular risk and targets of emerging therapeutic agents. Their relationship to cardiovascular events in the setting of high-dose statin therapy compared with placebo in patients with acute coronary syndrome is not known. METHODS AND RESULTS: sPLA(2) and Lp-PLA(2) mass and activity were measured in 2587 patients in the Myocardial Ischemia Reduction With Acute Cholesterol Lowering (MIRACL) trial at baseline and after 16 weeks of treatment with atorvastatin 80 mg/d or placebo. Baseline levels of sPLA(2) and Lp-PLA(2) mass and activity were not associated with the primary efficacy measure of the trial of death, myocardial infarction, or unstable angina. However, in the overall cohort, baseline sPLA(2) mass predicted risk of death after multivariable adjustment (hazard ratio for 2-fold increase, 1.30; 95% confidence interval, 1.09-1.56; P=0.004). This association remained significant when examined separately in the placebo group but not in the atorvastatin group. Compared with placebo, atorvastatin reduced median sPLA(2) mass (-32.1% versus -23.1%), sPLA(2) activity (-29.5% versus -19.2%), Lp-PLA(2) mass (-35.8% versus -6.2%), and Lp-PLA(2) activity (-24.3% versus 5.4%; P<0.001 for all). Atorvastatin reduced the hazard of death associated with elevated sPLA(2) mass and activity by ≈50%. CONCLUSIONS: sPLA(2) mass independently predicts death during a 16-week period after acute coronary syndrome. High-dose atorvastatin significantly reduces sPLA(2) and Lp-PLA(2) mass and activity after acute coronary syndrome and mitigates the risk of death associated with sPLA(2) mass. Atorvastatin may exert antiinflammatory effects on phospholipases that contribute to its therapeutic benefit after acute coronary syndrome.

Role of secretory phospholipase A2 in women with metabolic syndrome.

BACKGROUND & OBJECTIVES: Secretory phospholipase A2 (sPLA2), a member of the phospholipase A2 superfamily of enzymes that hydrolyses phospholipids, is a potentially useful plasma biomarker for atherosclerotic cardiovascular disease. Cardiovascular diseases are the leading cause of mortality in women. The purpose of this study was to investigate the correlation between cardiovascular risk factors and the sPLA2 levels in women with metabolic syndrome as compared to women without metabolic syndrome and men with metabolic syndrome. METHODS: Patients (n=100) with various cardiovascular risk factors consecutively evaluated at the Rehabilitation Hospital-Cardiology Department, Cluj-Napoca, Romania were enrolled during 2011, of whom 10 were excluded. The patients were divided in three groups: group 1 (37 women with metabolic syndrome), group 2 (27 men with metabolic syndrome), and group 3 (26 women without metabolic syndrome). Body weight, smoking habits, glycaemia, hypertension, and serum lipids fractions were analysed as cardiovascular factors. Serum sPLA2 activity was measured using the chromogenic method. RESULTS: There were no statistically significant correlations between sPLA2 levels and the investigated risk factors, irrespective of patient groups. However, there were significant positive correlations between sPLA2 and hsCRP in all three groups (P<0.05). In women with no metabolic syndrome an negative correlation was found between sPLA2 levels and HDL-C- r=-0.419, P=0.03. In men with metabolic syndrome there was a direct correlation between sPLA 2 levels and HOMA, r=0.43, P<0.05, 95% CI (-0.098; 1.15). INTERPRETATION & CONCLUSIONS: Women with metabolic syndrome did not display different sPLA2 levels as compared to men with metabolic syndrome and women without metabolic syndrome. However, women with metabolic syndrome demonstrated a low but positive correlation between sPLA2 and hsCRP levels.

Acute impact of apheresis on oxidized phospholipids in patients with familial hypercholesterolemia.

We measured oxidized phospholipids (OxPL), lipoprotein (a) [Lp(a)], and lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) pre- and postapheresis in 18 patients with familial hypercholesterolemia (FH) and with low(∼10 mg/dl; range 10-11 mg/dl), intermediate (∼50 mg/dl; range 30-61 mg/dl), or high (>100 mg/dl; range 78-128 mg/dl) Lp(a) levels. By using enzymatic and immunoassays, the content of OxPL and Lp-PLA(2) mass and activity were quantitated in lipoprotein density fractions plated in microtiter wells, as well as directly on apoB-100, Lp(a), and apoA-I immunocaptured within each fraction (i.e., OxPL/apoB and Lp-PLA(2)/apoB). In whole fractions, OxPL was primarily detected in the Lp(a)-containing fractions, whereas Lp-PLA(2) was primarily detected in the small, dense LDL and light Lp(a) range. In lipoprotein capture assays, OxPL/apoB and OxPL/apo(a) increased proportionally with increasing Lp(a) levels. Lp-PLA(2)/apoB and Lp-PLA(2)/apoA-I levels were highest in the low Lp(a) group but decreased proportionally with increasing Lp(a) levels. Lp-PLA(2)/apo(a) was lowest in patients with low Lp(a) levels and increased proportionally with increasing Lp(a) levels. Apheresis significantly reduced levels of OxPL and Lp-PLA(2) on apoB and Lp(a) (50-75%), particularly in patients with intermediate and high Lp(a) levels. In contrast, apheresis increased Lp-PLA(2)-specific activity (activity/mass ratio) in buoyant LDL fractions. The impact of apheresis on Lp(a), OxPL, and Lp-PLA(2) provides insights into its therapeutic benefits beyond lowering apoB-containing lipoproteins.

Refining the value of secretory phospholipase A2 as a predictor of acute chest syndrome in sickle cell disease: results of a feasibility study (PROACTIVE).

Acute chest syndrome (ACS) is defined as fever, respiratory symptoms and a new pulmonary infiltrate in an individual with sickle cell disease (SCD). Nearly half of ACS episodes occur in SCD patients already hospitalized, potentially permitting pre-emptive therapy in high-risk patients. Simple transfusion of red blood cells may abort ACS if given to patients hospitalized for pain who develop fever and elevated levels of secretory phospholipase A2 (sPLA2). In a feasibility study (PROACTIVE; ClinicalTrials.gov NCT00951808), patients hospitalized for pain who developed fever and elevated sPLA2 were eligible for randomization to transfusion or observation; all others were enrolled in an observational arm. Of 237 enrolled, only 10 were randomized; one of the four to receive transfusion had delayed treatment. Of 233 subjects receiving standard care, 22 developed ACS. A threshold level of sPLA2 ≥ 48 ng/ml gave optimal sensitivity (73%), specificity (71%) and accuracy (71%), but a positive predictive value of only 24%. The predictive value of sPLA2 was improved in adults and patients with chest or back pain, lower haemoglobin concentration and higher white blood cell counts, and in those receiving less than two-thirds maintenance fluids. The hurdles identified in PROACTIVE should facilitate design of a larger, definitive, phase 3 randomized controlled trial.

Cardiac troponin T measured by a high-sensitivity assay predicts recurrent cardiovascular events in stable coronary heart disease patients with 8-year follow-up.

BACKGROUND: The clinical relevance of slightly increased circulating troponin concentrations in patients with stable coronary heart disease (CHD) several weeks after an acute event or CABG has not been fully evaluated. METHODS: Baseline plasma concentrations of troponin T were measured with a high-sensitivity assay (hs-cTnT) (Roche Elecsys) in a cohort of 1050 CHD patients from 30 to 70 years of age. The prognostic value of hs-cTnT on a combined cardiovascular disease (CVD) end point after adjustment for covariates was determined with Cox proportional hazards modeling. RESULTS: The median hs-cTnT concentration was 10.9 ng/L (interquartile range, 5.1-18.9 ng/L). Increased hs-cTnT concentrations were associated with an older age, history of hypertension and diabetes, more advanced coronary artery disease, and other CHD risk factors. Furthermore, hs-cTnT concentration was strongly correlated with N-terminal pro-B-type natriuretic peptide (NT-proBNP) and cystatin C (ρ = 0.61, and ρ = 0.32, respectively; both P values <0.0001). During a median follow-up of 8.1 years, 150 patients (14.3%) experienced a secondary CVD event. In a multivariate model, hs-cTnT was associated with a hazard ratio (HR) for secondary events of 2.83 (95% CI, 1.68-4.79) when the extreme quartiles were compared. Further adjustment for cystatin C, NT-proBNP, and C-reactive protein attenuated this association only slightly (HR, 2.27; 95% CI, 1.31-3.95); P for trend < 0.002). ROC curve analysis of a clinical model that added hs-cTnT to a baseline model showed nonsignificant improvement in the area under the curve (0.69 vs 0.67), whereas the net reclassification improvement was 17.2% (P = 0.029). CONCLUSIONS: Slightly increased hs-cTnT concentrations in stable CHD patients are associated with several cardiovascular disorders and predict long-term CVD events.

A two-event in vitro model of acute chest syndrome: the role of secretory phospholipase A2 and neutrophils.

BACKGROUND: Acute chest syndrome (ACS) in sickle cell disease is associated with elevation of secretory phospholipase A(2) (sPLA(2) ). We hypothesize that sPLA(2) cleaves membrane lipids from sickled red blood cells (RBCs) causing PMN-mediated endothelial cell injury (ECI) as the second event in a two-event model. METHODS: Whole blood was collected from children when in steady state or daily during admissions for vaso-occlusive pain (VOC) or ACS. The plasma and RBCs were separated, sPLA(2) levels were measured, and the RBCs were incubated with sPLA(2) . Plasma and lipids, extracted from the plasma or the supernatant of sPLA(2) -treated RBCs, were assayed for PMN priming activity and used as the second event in a model of PMN-mediated ECI. Phosphatidylserine (PS) surface expression on RBCs was quantified by flow cytometry. RESULTS: Increased sPLA(2) -IIa levels were associated with ACS. SPLA(2) -liberated lipids from VOC and the plasma, plasma lipids and sPLA(2) -liberated lipids from ACS primed PMNs and caused PMN-mediated ECI (P < 0.01). RBCs from VOC had increased in PS surface expression versus steady state. CONCLUSIONS: ACS plasma and lipids and sPLA(2) -released lipids from RBCs during VOC or ACS induce PMN-mediated ECI. VOC elicited increases in PS surface expression providing a membrane substrate for sPLA(2) lysis of sickle RBCs.

Antioxidant and gastric cytoprotective prostaglandins properties of Cassia sieberiana roots bark extract as an anti-ulcerogenic agent.

BACKGROUND: Cassia sieberiana is a savannah tree with a wide phytotherapeutic application including the use of its roots in the management of various stomach disorders including gastric ulcer, stomach pains and indigestion. The aim of the study is to evaluate the antioxidant, gastric cytoprotective prostaglandins, secretory phospholipase A2, phytochemical and acute toxicity properties of Cassia sieberiana roots bark extract in a bid to justify its phytotherapeutic applications in gastric ulcer. METHODS: Antioxidant and radical scavenging activities of the roots bark extract of Cassia sieberiana were assayed. Serum secretory phospholipase A2 (sPLA2) concentration and activity and the formation of gastric mucosal prostaglandins E2 (PGE2) and I2 (PGI2) were also assessed. Comparisons between means were performed using analysis of variance (ANOVA) followed by Students Standard Newman-Keuls post hoc analysis to determine statistical significance. P < 0.05 was considered significant. RESULTS: The extract was found to possess significant ferric reducing antioxidant power and can scavenge hydroxyl radicals. The extract also possesses DPPH scavenging activity, can chelate ferrous ion and a dose-dependent protective effect against lipid peroxidation and free radical generation. Prostaglandin studies showed that the roots bark extract dose dependently increased gastric mucosal PGE2 and PGI2 levels and also decreased serum sPLA2 activity. Phytochemical analyses suggest that the roots extract contains polyhydroxyl/phenolic substances. Acute toxicity test showed no sign of toxicity up to a dose level of 2000 mg/kg body weight p.o. CONCLUSIONS: C. sieberiana roots extract possesses significant antioxidant and gastric cytoprotective prostaglandin properties as well as serum secretory phospholipase A2 inhibitory activity which could be due to its content of polyhydroxy and/or phenolic substances. This may justify its use as an anti-ulcerogenic agent in traditional medicine in West Africa.

[The secretory phospholipase A2 and transport of lipids by lipoproteins in patients with the risk of cardio-vascular pathology (the system "score") of lower and average degree. The diagnostic significance of the test].

The clinical and pathomorphologic data demonstrate that the most frequent cause of cardiac infarction is the formation of "soft" atheromatosis plaques in the intima of arteries. Their rupture results in thrombosis of coronary arteries. The plaques are characterized by higher content of triglycerides. On the basis of the research data, it is possible to validly consider that the detection of secretary phospholipase content A2 conjugated with lipoproteins is the test of systemic inflammatory response. This response is formed under atherosclerosis in vivo as a feedback to the accumulation in the intercellular medium of the endogenic flogogens (initiators of biological reaction of inflammation)--lipoproteins of lower density subclass A. Their utilization in the intima, as a pool of local interstitial tissue, by the resident macrophagocytes transformed from monocytes result in the formation of doth soft and disposed to laceration atheromatosis plaques and the atherothrombosis of coronary arteries and rarer of carotids. Concurrently, the increase of lipoproteins content in blood plasma is supposed to be the test of proliferation of cells in vivo, the smooth muscle cells of medium in particular. The simultaneous detection of content of secretory associated with lipoproteins phospholipase A2 and lipoprotein (a) can be considered as a valid risk factor of atherosclerosis and atherothrombosis--atheromatosis of intima of arteries with the formation of "soft" plaques in the intima, their laceration and thrombosis of coronary arteries and clinical presentation of cardiac infarction. The diagnostic triad of formation of soft plaques in the intima can be composed of the higher level of triglycerides, the content of protein of phospholipase A2 and lipoprotein (a).

LDL from obese patients with the metabolic syndrome show increased lipid peroxidation and activate platelets.

AIMS/HYPOTHESIS: This study assessed oxidative stress in LDL from obese patients with the metabolic syndrome and compared it with that in LDL from type 2 diabetic patients or control volunteers. It also determined the effect on platelets of LDL from the three groups. METHODS: The profiles of lipids, fatty acids and fatty acid oxidation products were determined in LDL isolated from plasma of patients with the metabolic syndrome, patients with type 2 diabetes and volunteers (n = 10 per group). The effects of LDL from the participant groups on the platelet arachidonic acid signalling cascade and aggregation were investigated. RESULTS: Compared with LDL from control volunteers, LDL from obese metabolic syndrome and type 2 diabetic patients had lower cholesteryl ester, higher triacylglycerol and lower ethanolamine plasmalogen levels. Proportions of linoleic acid were decreased in phosphatidylcholine and cholesteryl esters in LDL from both patient groups. Among the markers of lipid peroxidation, oxidation products of linoleic acid (hydroxy-octadecadienoic acids) and malondialdehyde were increased by 59% and twofold, respectively in LDL from metabolic syndrome and type 2 diabetic patients. LDL from metabolic syndrome and type 2 diabetic patients were equally potent in activating the platelet arachidonic acid signalling cascade through increased phosphorylation of p38 mitogen-activated protein kinase and cytosolic phospholipase A(2), and through increased thromboxane B(2) formation. LDL from patients with the metabolic syndrome and type 2 diabetes potentiated platelet aggregation by threefold and 3.5-fold respectively, whereas control LDL had no activating effects on platelets. CONCLUSIONS/INTERPRETATION: The metabolic syndrome in obese patients, without or with diabetes, is associated with increased oxidative stress in LDL, which triggers platelet activation.

The sPLA2 Inhibition to Decrease Enzyme Release after Percutaneous Coronary Intervention (SPIDER-PCI) trial.

BACKGROUND: Secretory phospholipase A(2) (sPLA(2)) may play a role in myonecrosis after elective percutaneous coronary intervention (PCI). Inhibition of this enzyme may have a beneficial effect. The central hypothesis of this study was that treatment with varespladib, a small-molecule inhibitor of sPLA(2) would reduce postprocedural release of cardiac biomarkers after elective percutaneous coronary intervention. METHODS AND RESULTS: Between October 2007 and June 2009, 144 stable patients were randomized in a phase II trial to receive varespladib 500 mg PO BID or placebo 3 to 5 days before and for 5 days after elective percutaneous coronary intervention. The primary end point was elevation of troponin I or creatine kinase-MB above the upper limit of normal at 6 to 8 or 18 to 24 hours after percutaneous coronary intervention. Mean age was 63±10 and 64±10 years, with 38% and 42% with diabetes mellitus and 29% and 28% with prior myocardial infarction for the varespladib and placebo groups, respectively. The primary end point occurred in 75% of varespladib and 63% of placebo patients (P=0.14). Troponin I 3 times the upper limit of normal was observed in 57% and 50% (P=0.39) and creatine kinase-MB 2 times the upper limit of normal in 14% and 3% (P=0.018). Median (first and third quartiles) change in high-sensitivity C-reactive protein in these 2 groups was 0.65 mg/L (-0.18 and 1.48) and 0.70 mg/L (0.00 and 1.50) at 18 to 24 hours (P=0.81) and 0.20 mg/L (-0.70 and 1.40) and 0.60 mg/L (-0.12 and 1.72) at 3 to 5 days (P=0.23), whereas change in sPLA(2) activity at 3 to 5 days in a subset was -2.85 ng/ml (-3.40 and -1.85) and 0.25 ng/ml (-0.20 and 0.85) (P<0.001). CONCLUSIONS: Inhibition of sPLA(2) by varespladib administered for 3 to 5 days before the procedure does not reduce periprocedural myonecrosis associated with elective percutaneous coronary intervention. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00533039.

Prognostic utility of secretory phospholipase A(2) in patients with stable coronary artery disease.

BACKGROUND: Secretory phospholipase A(2) (sPLA(2)) may contribute to atherogenesis. To date, few prospective studies have examined the utility of sPLA(2) for risk stratification in coronary artery disease (CAD). METHODS: We measured plasma sPLA(2) activity at baseline in 3708 subjects in the PEACE randomized trial of trandolapril vs placebo in stable CAD. Median follow-up was 4.8 years. We used Cox regression to adjust for demographics, clinical risk factors, apolipoprotein B, apolipoprotein A1, and medications. RESULTS: After multivariable adjustment, sPLA(2) was associated with an increased risk of cardiovascular death, myocardial infarction, or stroke (adjusted hazard ratio Q4:Q1 1.55, 95% CI 1.13-2.14) and cardiovascular death or heart failure (1.91, 1.20-3.03). In further multivariable assessment, increased activity levels of sPLA(2) were associated with the risk of cardiovascular death, myocardial infarction, or stroke (adjusted hazard ratio 1.47, 95% CI 1.06-2.04), independent of lipoprotein-associated phospholipase A(2) mass and C-reactive protein, and modestly improved the area under the curve (AUC) beyond established clinical risk factors (AUC 0.668-0.675, P = 0.01). sPLA(2), N-terminal pro-B-type natriuretic peptide, and high-sensitivity cardiac troponin T all were independently associated with cardiovascular death or heart failure, and each improved risk discrimination (P = 0.02, P < 0.001, P < 0.001, respectively). CONCLUSIONS: sPLA(2) activity provides independent prognostic information beyond established risk markers in patients with stable CAD. These data are encouraging for studies designed to evaluate the role of sPLA(2) as a therapeutic target.

Metabolic syndrome and carotid intima-media thickness in young adults: roles of apolipoprotein B, apolipoprotein A-I, C-reactive protein, and secretory phospholipase A2: the cardiovascular risk in young Finns study.

OBJECTIVE: Aberrations in apolipoprotein (apo) metabolism and increased systemic inflammation associate with the metabolic syndrome (MetS) and may contribute to its atherogenicity. We examined whether the association between carotid atherosclerosis and MetS in a population of young adults is mediated by apoB and apoA-I and/or by inflammatory markers C-reactive protein and type II secretory phospholipase A2. METHODS AND RESULTS: We used cross-sectional and 6-year prospective data from the cardiovascular risk in young Finns study. In young adults (aged 24 to 39 years), apoB, C-reactive protein, and type II secretory phospholipase A2 enzyme activity were significantly higher and apoA-I lower in subjects with MetS (N=325) than in subjects without MetS (N=1858). In prospective analysis (N=1587), both MetS and high apoB predicted (P<0.0001) incident high carotid intima-media thickness, defined as carotid intima-media thickness >90th percentile and/or plaque. The association between MetS and incident high carotid intima-media thickness was attenuated by approximately 40% after adjustment with apoB. Adjustments with apoA-I, C-reactive protein, or type II secretory phospholipase A2 did not diminish the association. CONCLUSIONS: High levels of apoB, C-reactive protein, and type II secretory phospholipase A2 and low levels of apoA-I associate with MetS in young adults. The atherogenicity of MetS in this population assessed by incident high carotid intima-media thickness appears to be substantially mediated by elevated apoB but not inflammatory markers.

Secretory phospholipase A2: a marker of infection in febrile children presenting to a pediatric ED.

BACKGROUND: Fever is a common presenting complaint to the emergency department (ED), and the evaluation of the febrile child remains a challenging task. OBJECTIVE: The aim of this study was to examine the relationship between secretory phospholipase A2 (sPLA2) and infection in febrile children. METHODS: A prospective convenience sample of children presenting with fever to an urban pediatric ED were studied. Blood and urine cultures, a complete blood count, and serum concentrations of sPLA2 were obtained, and patients were compared based on their final diagnosis of either a viral or bacterial infection. RESULTS: In the 76 patients enrolled, 60 were diagnosed with a viral infection, 14 with a bacterial infection, 1 with Kawasaki disease, and 1 with acute lymphoblastic leukemia. The difference in the serum concentration of sPLA2 in patients with viral infections (22 ± 34 ng/mL) versus those with bacterial infections (190 ± 179 ng/mL) was statistically significant (P < .0001). Receiver operator characteristic curve analysis revealed that sPLA2 was more accurate at predicting bacterial infection (area under the curve = 0.89) than the total white blood cell count (area under the curve = 0.71) and that a value of more than 20 ng/mL had a sensitivity of 93%, specificity of 67%, positive predictive value of 39%, and negative predictive value of 97%. CONCLUSION: Secretory phospholipase A2 differs significantly in children with viral versus bacterial infection and seems to be a reliable screening test for bacterial infection in febrile children.