Effects of Serum Estradiol on Proprotein Convertase Subtilisin/Kexin Type 9 Levels and Lipid Profiles in Women Undergoing In Vitro Fertilization.

BACKGROUND: The mechanisms underlying the impact of estradiol (E2) on low-density lipoprotein cholesterol (LDL-C) levels are not completely understood, although a role for proprotein convertase subtilisin/kexin type 9 (PCSK9) has been proposed. We aimed to investigate the association between levels of E2, PCSK9, and lipid parameters in premenopausal women undergoing in vitro fertilization (IVF). METHODS: Healthy women undergoing IVF in the Department of Obstetrics and Gynecology of the University General Hospital of Ioannina were recruited. Their levels of E2, PCSK9, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), LDL-C, and triglycerides (TGs) were measured 10 days after ovarian depression (E2min) and 7 days after ovarian stimulation (E2max). RESULTS: We included 34 consecutive women of median age 38 (interquartile range 26-46) years who underwent a full IVF cycle. As expected, E2 levels increased by 329.6% from E2min to E2max (108 [47-346] to 464 [241-2471] pg/mL, p < 0.05). During the same time, serum PCSK9 levels decreased by 30.8% (245 ± 80 to 170 ± 64 ng/mL, p < 0.05). TC, LDL-C, and TGs decreased by 0.4%, 3.8%, and 2.2%, respectively, while HDL-C levels increased by 5.3% (all p = NS). CONCLUSIONS: The rise in endogenous E2 during an IVF cycle was related with a significant decline in serum PCSK9 levels, but no significant change in plasma lipids during a 7-day period.

Development of a Novel Apigenin Dosage form as a Substitute for the Modern Triple Antithrombotic Regimen.

The simultaneous administration of three antiplatelet agents has been proposed as an efficient strategy for the secondary prevention of atherothrombotic events and is included in the European guidelines. However, this strategy presented an increased risk of bleeding; therefore, the identification of new antiplatelet agents, with improved efficacy and diminished side effects, is of great importance. In silico studies, UPLC/MS Q-TOF plasma stability, in vitro platelet aggregation experiments, and pharmacokinetic studies were exploited. In the present study, it has been predicted that the flavonoid apigenin could target different platelet activation pathways, including P2Y12, protease-activated receptor-1 (PAR-1), and cyclooxygenase 1 (COX-1). To enhance apigenin's potency, hybridization with docosahexaenoic acid (DHA) was performed, as fatty acids have illustrated potent efficacy against cardiovascular diseases (CVDs). The new molecular hybrid, termed 4'-DHA-apigenin, demonstrated enhanced inhibitory activity against platelet aggregation induced by thrombin receptor activator peptide-6 (TRAP-6), adenosine diphosphate (ADP), and arachidonic acid (AA), with respect to the parent apigenin. The 4'-DHA-apigenin hybrid illustrated an almost 2-fold enhanced inhibitory activity, with respect to apigenin, and an almost 3-fold enhanced inhibitory activity, with respect to DHA, for the ADP-induced platelet aggregation. Additionally, the hybrid presented a more than 12-fold enhanced inhibitory activity with respect to DHA for the TRAP-6 induced platelet aggregation. Furthermore, a 2-fold enhanced inhibitory activity was recorded for the 4'-DHA-apigenin hybrid for the AA-induced platelet aggregation with respect to apigenin. To surmount the reduced LC-MS based plasma stability, a novel dosage form in olive oil has been developed. The 4'-DHA-apigenin olive oil-based formulation presented an enhanced antiplatelet inhibitory effect in three activation pathways. To further explore the pharmacokinetic profile of 4'-DHA-apigenin in olive oil formulations, a UPLC/MS Q-TOF protocol has been established to quantify the serum levels of apigenin after oral administration to C57BL/6J wild type mice. The olive oil-based formulation of 4'-DHA-apigenin demonstrated an increase in apigenin bioavailability of 262 %. This study may offer a new therapeutic strategy tailored to improve the treatment of CVDs.

Levels of Circulating IgM and IgY Natural Antibodies in Broiler Chicks: Association with Genotype and Farming Systems.

Naturally occurring antibodies (NAbs), which are major components of innate immunity, exist in circulation under healthy conditions without prior antigenic stimulation and are able to recognize both self- and non-self-constituents. The present study aimed at identifying potential immunological differences between commercial fast- and slow-growth broilers (n = 555) raised in conventional and free-range systems, respectively, through the use of the specificity, isotypes and levels of circulating NAbs. The possible beneficial effect of oregano-based dietary supplementation was also evaluated. To this end, serum IgM and IgY NAbs against self- (actin and DNA) and non-self- antigens (trinitrophenol and lipopolysaccharide) were measured by ELISA and further correlated with genotype, season and performance. Significantly higher levels of IgM NAbs against all antigens were found in slow-growth compared to fast-growth broilers. IgM NAb levels were also significantly increased in dietarily supplemented slow-growth broilers versus those consuming standard feed. Moreover, significantly elevated levels of anti-DNA IgY NAbs were found in fast-growth compared to slow-growth broilers, whereas the opposite was observed for anti-LPS IgY NAbs. Multivariate linear regression analysis confirmed multiple interactions between NAb levels, genotype, season and performance. Overall, serum NAbs have proven to be valuable innovative immunotools in the poultry industry, efficiently differentiating fast-growing versus slow-growing broilers, and dietary supplementation of plant extracts can enhance natural immunity.

Oxidized phospholipids and lipoprotein-associated phospholipase A2 (Lp-PLA2 ) in atherosclerotic cardiovascular disease: An update.

Inflammation and oxidative stress conditions lead to a variety of oxidative modifications of lipoprotein phospholipids implicated in the occurrence and development of atherosclerotic lesions. Lipoprotein-associated phospholipase A2 (Lp-PLA2 ) is established as an independent risk biomarker of atherosclerosis-related cardiovascular disease (ASCVD) and mediates vascular inflammation through the regulation of lipid metabolism in the blood and in atherosclerotic lesions. Lp-PLA2 is associated with low- and high-density lipoproteins and Lipoprotein (a) in human plasma and specifically hydrolyzes oxidized phospholipids involved in oxidative stress modification. Several oxidized phospholipids (OxPLs) subspecies can be detoxified through enzymatic degradation by Lp-PLA2 activation, forming lysophospholipids and oxidized non-esterified fatty acids (OxNEFAs). Lysophospholipids promote the expression of adhesion molecules, stimulate cytokines production (TNF-α, IL-6), and attract macrophages to the arterial intima. The present review article discusses new data on the functional roles of OxPLs and Lp-PLA2 associated with lipoproteins.

PCSK9 is minimally associated with HDL but impairs the anti-atherosclerotic HDL effects on endothelial cell activation.

Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) regulates the cell-surface localization of LDL receptors in hepatocytes and is associated with LDL and lipoprotein(a) [Lp(a)] uptake, reducing blood concentrations. However, the connection between PCSK9 and HDL is unclear. Here, we investigated the association of plasma PCSK9 with HDL subpopulations and examined the effects of PCSK9 on the atheroprotective function of HDL. We examined the association of PCSK9 with HDL in apoB-depleted plasma by ELISA, native PAGE, and immunoblotting. Our analyses showed that upon apoB-depletion, total circulating PCSK9 levels were 32% of those observed in normolipidemic plasma, and only 6% of PCSK9 in the apoB-depleted plasma, including both the mature and furin-cleaved forms, was associated with HDL. We also show human recombinant PCSK9 abolished the capacity of reconstituted HDL to reduce the formation of ROS in endothelial cells, while a PCSK9-blocking antibody enhanced the capacity of human HDL (in apoB-depleted plasma) to reduce ROS formation in endothelial cells and promote endothelial cell migration. Overall, our findings suggest that PCSK9 is only minimally associated with HDL particles, but PCSK9 in apoB-depleted plasma can affect the atheroprotective properties of HDL related to preservation of endothelial function. This study contributes to the elucidation of the pathophysiological role of plasma PCSK9 and highlights further the anti-atherosclerotic effect of PCSK9 inhibition.

Plasma VEGF and Leptin Values in Patients With Gastric Intestinal Metaplasia and Metabolic Syndrome.

Intestinal metaplasia of the stomach (IM) is considered a pre-cancerous lesion and is a potential precursor to adenocarcinoma. Metabolic syndrome (MetS) has been associated with lesions to the gastrointestinal tract such as the risk of developing Barett esophagus. Vascular endothelial growth factor and leptin have been associated with either gastrointestinal tract carcinogenesis or MetS. In this context, this study was designed to analyze plasma levels of VEGF and leptin in patients with IM and MetS. Four groups of 137 participants (a control group and three patient groups, IM, MetS and IM- MetS) were created. Inclusion criteria for the presence of IM were endoscopic findings and histological confirmation, while for MetS the ATP III and IDF guidelines. Levels of plasma vascular endothelial growth factor (VEGF) and leptin (Leptin) were determined. VEGF levels were increased in IM (IM vs Control, p=0,011) and IM-MetS groups (IM-MetS vs Control, p <0.001 and IM-MetS vs MetS, p=0.001). Leptin levels were found to be increased in the MetS group (MetS vs. Control, p <0.001 and MetS vs IM, p <0.001) and in IM-MetS (IM-MetS vs Control, p = 0.002, IM-MetS vs IM, p=0.033). Patients with intestinal metaplasia and metabolic syndrome (I M - Me t S g r o u p) have elevated levels of VEGF, while leptin levels were associated predominantly with MetS and not with IM.

Urine 8-Hydroxyguanine (8-OHG) in Patients Undergoing Surgery for Colorectal Cancer.

PURPOSE: Cellular RNA is less compact than DNA, more easily accessible to ROS and therefore could be more susceptible to oxidative damage. This study was conceived in order to analyze the RNA oxidative damage in the urine of patients undergoing operation for colorectal cancer (CRC), to compare with healthy controls, and correlate with the stage. MATERIALS AND METHODS: The study population was constituted by a group of 147 patients and a group of 128 healthy controls. Urine and blood samples were collected before the colonoscopy in all participants and 24 hours post-operatively for those who underwent surgery. Urine 8-hydroxyguanine (8-OHG) was determined as marker of RNA oxidation, and serum uric acid (UA) as antioxidant marker. RESULTS: Preoperatively, 8-OHG (ng/ml) values of CRC patients were found to be significantly higher than those of controls (p = 0.001). More specifically, stages II/III had significantly higher 8-OHG values (p < 0.001 and p = 0.007) than stages 0/I. Post-operatively, 8-OHG values were similar to controls (p = 0.053). Preoperatively, UA values (mg/dl) were significantly lower (p = 0.001), while postoperatively were similar to controls (p = 0.069). CONCLUSION: Oxidative RNA damage occurs in CRC patients. Stages II/III are associated with higher values of 8-OHG than stages 0/I. 8-OHG could act as a marker for the identification of patients with advanced disease.

Association between PCSK9 Levels and Markers of Inflammation, Oxidative Stress, and Endothelial Dysfunction in a Population of Nondialysis Chronic Kidney Disease Patients.

Proprotein convertase subtilisin/kexin 9 (PCSK9) plays an important role in lipid metabolism while available literature regarding its involvement in the pathogenesis of atherosclerosis and in the expression of genes associated with apoptosis and inflammation is constantly increasing. Patients with chronic kidney disease (CKD) experience disproportionately increased cardiovascular morbidity and mortality due to dyslipidemia, accelerated atherosclerosis, inflammation, oxidative stress, and other risk factors. In the present cross-sectional study, we investigated the possible association of serum PCSK9 levels with markers of inflammation, oxidative stress, and endothelial damage in patients with CKD. Patients and Methods. Ninety-two patients with CKD stages II-ΙV (eGFR CKD-EPI 47.3 ± 25.7 ml/min/1.73 m2, mean age 66 years, 51 men) were included in the study. Plasma PCSK9 levels were correlated with comorbidities (arterial hypertension, diabetes mellitus, and history of cardiovascular disease), renal function indices (eGFR, proteinuria-UPR/24 h), lipid parameters (LDL-cholesterol, HDL-cholesterol, triglycerides, Lp(a), APO-A1, and APO-B), and soluble biomarkers of inflammation, oxidative stress, and endothelial damage (hs-CRP, fibrinogen, 8-epiPGF2a, ox-LDL, IL-6, TNF-α, sICAM-1, and sVCAM-1). Results. The mean plasma value of PCSK9 was 278.1 ng/ml. PCSK9 levels showed direct correlation with serum triglycerides (p = 0.03), Lp(a) (p = 0.01), and sICAM-1 levels (p = 0.03). There was no significant correlation between PCSK9 levels and indices of the renal function, other lipid profile parameters, inflammatory markers, or comorbidities. Multiple regression analysis showed a significant effect of Lp(a) on PCSK9 levels, and for each unit of higher Lp(a), an increase by 3.082 is expected (95% CI: 0.935-5.228, p = 0.006). At the same time, patients receiving statins are expected to have on average 63.8 ng/ml higher PCSK9 values compared to patients not receiving statins (95% CI: 14.6-113.5, p = 0.012). Conclusion. Plasma levels of PCSK9 in nondialysis CKD patients are correlated with endothelial dysfunction and lipid metabolism parameters. Statin intake increases PCSK9 levels significantly in this patient population. PCSK9 levels are not correlated with the severity of kidney disease. Major prospective studies are necessary to investigate the role of PCSK9 in the atherosclerotic cardiovascular outcome in CKD.

Vitamin D status and cardiometabolic risk factors in Greek adolescents with obesity - the effect of vitamin D supplementation: a pilot study.

INTRODUCTION: Obesity is associated with cardiovascular disease (CVD) risk factors as well as decreased 25(OH) vitamin D serum levels. We aimed to study 25(OH) vitamin D levels in adolescents with obesity compared with normal weight controls in association with CVD risk factors, and the possible effect of vitamin D supplementation. MATERIAL AND METHODS: In a cross-sectional study, 69 obese and 34 normal-weight adolescents were included. In an interventional study 15 adolescents with obesity and vitamin D insufficiency were given 2000 IU vitamin D per os daily for 3 months. RESULTS: Adolescents with obesity had significantly lower 25(OH) vitamin D levels compared with normal-weight controls (12.0 (3.0-36.0) vs. 34.0 (10.0-69.0) ng/ml, respectively, p < 0.001). In adolescents with obesity, 25(OH) vitamin D was inversely associated with leptin even after adjustment for body mass index (BMI) (r = -0.340, p = 0.009). Conversely, 25(OH) vitamin D was not related with other parameters, such as BMI, blood pressure, lipids, glucose, insulin, homeostasis model assessment (HOMA) index, adiponectin, leptin/adiponectin ratio, and visfatin levels. Following supplementation in 15 vitamin D insufficient adolescents with obesity, 25(OH) vitamin D significantly increased (from 17.3 (12.5-27.8) to 32.6 (14.3-68.0) ng/ml, p = 0.005) and so did low-density lipoprotein cholesterol (LDL-C) (from 85.4 ±9.5 to 92.1 ±15.8 mg/dl, p = 0.022), while there were reductions in glycated haemoglobin (HbA1c) (from 5.8 ±0.2 to 5.5 ±0.1%, p = 0.03) and leptin (from 19.7 (7.8-45.5) to 15.1 (4.3-37.3) ng/ml, p = 0.03). Oxidised LDL, paraoxonase, arylesterase, and urine isoprostanes remained unchanged. CONCLUSIONS: Adolescents with obesity had lower 25(OH) vitamin D, which may be associated with higher leptin levels. Vitamin D supplementation may lead to HbA1c and leptin reductions, but also to an increase in LDL-C.

Effect of combined vitamin D administration plus dietary intervention on oxidative stress markers in patients with metabolic syndrome: A pilot randomized study.

BACKGROUND: Metabolic syndrome (MetS) patients can have low 25-hydroxyvitamin D 25(OH)VitD levels, which may be associated with increased oxidative stress. There is little data on the effect of 25(OH)VitD administration plus dietary intervention on oxidative stress markers in these patients. AIM: To study the effect of 25(OH)VitD administration plus dietary intervention on oxidative stress markers in MetS patients. METHODS: This is a pre-specified analysis of a previously published study (NCT01237769 ClinicalTrials.gov). MetS participants (n = 50, 52 ± 10 years) were given dietary instructions and were randomized to 25(OH)VitD 2.000 IU/day p.o. (Suppl group) or no supplementation (No-Suppl group). Serum 25(OH)VitD, oxidized LDL (ox-LDL), paraoxonase activity (PON-1), arylesterase activity (ARYL) and urine 8-isoprostane (8-iso-PGF2a) levels were measured at baseline and after 3 months. RESULTS: MetS patients had low baseline 25(OH)VitD levels, which increased by 90% in the Suppl group [from 16.1 (3.3-35.1) to 30.6 (8.4-67.6) ng/mL, p = 0.001] and by 33.3% in the No-Suppl group [from 9.9 (4.0-39.6) to 13.2 (3.5-36.8) ng/mL, p = NS] after intervention. Ox-LDL, PON-1 and ARYL did not change significantly at follow-up in both groups, except for urine 8-iso-PGF2a levels that decreased by 22.7% in the Suppl group [from 48.8 (26.8-137.1) to 37.7 (12.3-99.0) ng/mmol creatinine, p = 0.015] and by 14.4% in No-Suppl group [from 45.8 (16.6-99.3) to 39.2 (13.3-120.1) ng/mmol creatinine, p = NS]. The reduction in 8-iso-PGF2a levels did not differ significantly between the 2 groups. CONCLUSION: The administration of 25(OH)VitD plus dietary intervention in patients with MetS was not associated with meaningful reductions in oxidative stress markers compared with dietary intervention alone.

Pharmacology of PCSK9 Inhibitors: Current Status and Future Perspectives.

Protein Convertase Subtilisin/Kexin type 9 (PCSK9) is a serine protease primarily expressed in the liver, which represents the main source of the plasma enzyme. The best characterized function of PCSK9 relates to the binding to Low-Density Lipoprotein Receptor (LDL-R) in hepatocytes, increasing its endosomal and lysosomal degradation. This results in the inhibition of LDL-R recycling to the cell surface and therefore the reduction of the hepatic uptake of LDL, leading to the increase in plasma levels of LDL-cholesterol, a major risk factor of Cardiovascular Diseases (CVD). Therefore, PCSK9 is an important therapeutic target to reduce LDLcholesterol levels. PCSK9 inhibition can occur at the level of its interaction with LDL-R as well as at several sites across the pathway of its intracellular synthesis and secretion. Two fully human mAbs, Alirocumab and Evolocumab, that selectively bind to PCSK9 and prevent its interaction with the LDL-R, are currently used in the clinical practice. These mAbs are the most potent cholesterol-lowering agents available today and can decrease LDLcholesterol levels up to 73% while they also reduce the risk of atherosclerotic CVD. Ongoing research has led to the development of new PCSK9 inhibitors through genome editing technology (CRISPR-Cas9), siRNA or antisense oligonucleotide silencing agents, vaccines, mimetic peptides, adnectins, and inhibitors of PCSK9 secretion. The above inhibitors have been studied in vitro, in animal models in vivo, as well as in phase I and II trials and have demonstrated an important efficacy profile. Future studies with these agents will demonstrate their possible clinical value and will further enlighten the various targets and activities of PCSK9 intracellularly and extracellularly, the underlying mechanisms, as well as the clinical significance of these actions beyond the inhibition of LDL-R recycling.

Effects of increased body weight and short-term weight loss on serum PCSK9 levels - a prospective pilot study.

INTRODUCTION: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is associated with low-density lipoprotein (LDL) catabolism, but its serum concentration is not uniformly associated with cardiovascular disease in clinical studies. Obesity is linked with increased cardiovascular risk, but the effect of increased body weight and short-term weight loss on serum PCSK9 levels is not well studied. MATERIAL AND METHODS: The aim of this prospective pilot study was to assess differences in serum PCSK9 levels (determined with a quantitative sandwich enzyme immunoassay) between otherwise healthy drug-naïve obese subjects and healthy individuals with normal body weight. Additionally, PCSK9 levels were determined at baseline and after a 3-month weight-loss program with a low-fat diet in a randomly assigned subgroup of the obese subjects (n = 15). RESULTS: Obese subjects (n = 35) were older (age: 43 ±11 years) and had significantly higher body mass index, total cholesterol, triglycerides, LDL cholesterol (LDL-C), apolipoprotein B and homeostasis model assessment of insulin resistance (HOMA) index levels, as well as significantly lower high-density lipoprotein cholesterol (HDL-C) concentration, compared with normal-weight subjects (n = 20, age: 35 ±6 years). Serum PCSK9 levels were significantly higher in obese subjects compared with normal-weight individuals, even after adjustment for age, LDL-C, triglycerides, HDL-C, apolipoprotein A1, apolipoprotein B, apolipoprotein E, glucose, insulin and HOMA index levels (p = 0.018). Obese subjects experienced significant weight loss (from 109 ±22 to 104 ±23 kg, p < 0.01), but serum PCSK9 levels did not significantly change after the 3-month weight-loss program. CONCLUSIONS: Serum PCSK9 levels are higher in obese subjects than in normal-weight individuals. Short-term weight loss with a low-fat diet does not significantly affect PCSK9 levels.

Pleiotropic effects of apolipoprotein C3 on HDL functionality and adipose tissue metabolic activity.

APOC3 is produced mainly by the liver and intestine and approximately half of plasma APOC3 associates with HDL. Though it was believed that APOC3 associates with HDL by simple binding to preexisting particles, recent data support that biogenesis of APOC3-containing HDL (APOC3-HDL) requires Abca1. Moreover, APOC3-HDL contributes to plasma triglyceride homeostasis by preventing APOC3 association with triglyceride-rich lipoproteins. Interestingly, APOC3-HDL also shows positive correlation with the morbidly obese phenotype. However, the roles of APOC3 in HDL functionality and adipose tissue metabolic activity remain unknown. Therefore, here we investigated the direct effects of APOC3 expression on HDL structure and function, as well as white adipose tissue (WAT) and brown adipose tissue (BAT) metabolic activity. C57BL/6 mice were infected with an adenovirus expressing human APOC3 or a recombinant attenuated control adenovirus expressing green fluorescent protein and blood and tissue samples were collected at 5 days postinfection. HDL was then analyzed for its apolipoprotein and lipid composition and particle functionality. Additionally, purified mitochondria from BAT and WAT were analyzed for uncoupling protein 1, cytochrome c (Cytc), and Cytc oxidase subunit 4 protein levels as an indirect measure of their metabolic activity. Serum metabolomic analysis was performed by NMR. Combined, our data show that APOC3 modulates HDL structure and function, while it selectively promotes BAT metabolic activation.

Hypertrophic Mesenteric Adipose Tissue May Play a Role in Atherogenesis in Inflammatory Bowel Diseases.

BACKGROUND: Adipokines released by the adipose tissue are known to play a role in atherogenesis. The hypertrophic mesenteric fat in patients with inflammatory bowel diseases (IBD) also produces adipokines that are considered to play a role in intestinal inflammation. Whether they also contribute to accelerated atherosclerosis in IBD is unknown. The aim of this study was to assess the role of 2 adipokines, resistin and adiponectin, in IBD. METHODS: We previously published data on 3 markers of cardiovascular risk, carotid intima-media thickness, carotid-femoral pulse wave velocity, and lipoprotein-associated phospholipase A2, in 44 patients with IBD and 44 controls matched for established cardiovascular risk factors. In this study, we measured resistin and adiponectin levels, and assessed their correlations with carotid intima-media thickness, pulse wave velocity, and lipoprotein-associated phospholipase A2. RESULTS: Resistin levels were significantly higher in patients with IBD (13.7 versus 10 ng/mL; P = 0.022), but there was no difference in adiponectin levels. Resistin levels were significantly higher in patients with active disease compared with those in remission (18.9 versus 11.3 ng/mL; P = 0.014). Adiponectin levels were significantly lower in Crohn's disease compared with ulcerative colitis (6736.3 ± 3105 versus 10,476.1 ± 5575.7 ng/mL; P = 0.026). Adiponectin correlated inversely with pulse wave velocity (rho = -0.434; P < 0.0005) and carotid intima-media thickness (rho = -0.255; P = 0.021). CONCLUSIONS: This is the first study to suggest that adipokines produced by the hypertrophic mesenteric fat in IBD may play a role not only in intestinal inflammation but also in atherogenesis. Resistin has mainly pro-inflammatory properties, whereas adiponectin likely exerts an angioprotective effect.

The relationship between retinol-binding protein 4 and apolipoprotein B-containing lipoproteins is attenuated in patients with very high serum triglycerides: A pilot study.

OBJECTIVE: The investigation of the association between retinol-binding protein 4 (RBP4) and lipoproteins in subjects with hypertriglyceridemia. DESIGN: Forty-six obese or overweight hypertriglyceridemic patients were studied at baseline and 20 of them underwent a hypocaloric low-fat diet for 3 months. RESULTS: Plasma RBP4 levels were positively correlated with serum triglycerides (TG) in the subgroup of patients with TG <200 mg/dL (r=0.453, p=0.039) and negatively correlated with TG in patients with TG ≥200 mg/dL (r=-0.487, p=0.019). In the subgroup with TG <200 mg/ dL, subjects with circulating RBP4 above the median 46 mg/L had higher levels of intermediate density lipoprotein-cholesterol (IDL-C), low-density lipoprotein-cholesterol (LDL-C) and apolipoprotein B (ApoB), while these differences were absent in patients with TG ≥200 mg/dL. The associations of percentage changes of circulating RBP4 with the percentage changes of LDL-C, very low-density lipoprotein-cholesterol (VLDL-C) and ApoB were positive after the first month and 3 months of diet for patients with baseline TG <200 mg/dL, while no correlations existed for patients with TG ≥200 mg/dL. CONCLUSIONS: The positive association between circulating RBP4 and ApoB-containing lipoproteins in a steady metabolic state, as well as during a hypocaloric diet, appears to be attenuated in patients with very high TG.

Amyloid-beta (1-40) and the risk of death from cardiovascular causes in patients with coronary heart disease.

BACKGROUND: The amyloid beta peptide is the major protein constituent of neuritic plaques in Alzheimer disease and appears to play a central role in vascular inflammation pathophysiology. OBJECTIVES: This study sought to determine the clinical value of amyloid-beta 1-40 (Abeta40) measurement in predicting cardiovascular (CV) mortality in patients with coronary heart disease (CHD) and arterial stiffness progression in young healthy subjects. METHODS: Abeta40 was retrospectively measured in blood samples collected from 3 independent prospective cohorts and 2 case-control cohorts (total N = 1,464). Major adverse cardiac events (MACE) were assessed in the 2 prospective cohorts (n = 877) followed for a median of 4.4 years. To look at effects on subclinical disease, arterial stiffness was evaluated at baseline and after 5-year follow-up (n = 107) in young healthy subjects. The primary endpoint was the predictive value of Abeta40 for CV mortality and outcomes in patients with CHD. RESULTS: In Cox proportional hazards models adjusted for age, sex, estimated glomerular filtration rate, left ventricular ejection fraction, high-sensitivity C-reactive protein, and high-sensitivity troponin T, Abeta40 independently predicted CV death and MACE in patients with CHD (p < 0.05 for all). After multivariate adjustment, Abeta40 levels conferred a substantial enhancement of net reclassification index and integrated discrimination improvement of individuals at risk in the total combined CHD cohort over the best predictive model. Further cohort-based analysis revealed that Abeta40 levels were significantly and independently associated with arterial stiffness progression, incident subclinical atherosclerosis, and incident CHD. CONCLUSIONS: Measuring blood levels of Abeta40 identified patients at high risk for CV death.

Oxidative stress in multi-port and single-port cholecystectomy.

BACKGROUND: This study was designed to analyze and compare plasma levels of 8-isoprostane (8-epiPGF2α), a biomarker of lipid peroxidation, and uric acid (UA), a marker of the antioxidant status, in standard laparoscopic (LC) and laparoendoscopic single-site cholecystectomy (LSSC). MATERIALS AND METHODS: Forty patients with noncomplicated cholelithiasis were randomized to undergo either LSSC (n = 20) or LC (n = 20). The patients had body mass index <30, American Society of Anesthesiologists score I or II, and no previous upper gastrointestinal surgery. Blood samples were taken preoperatively and 6 h and 24 h postoperatively. Levels of 8-epiPGF2α were determined using enzyme-linked immunosorbent assay, whereas levels of UA were calculated using automated analyzer. RESULTS: No significant differences were observed in operative data among the groups. Levels of 8-epiPGF2α were significantly higher in LSSC compared with LC at 6 h (P = 0.003) and 24 h (P < 0.001). 8-epiPGF2α levels showed significant changes over time in LC (LSSC: P = 0.720, LC: P < 0.001). UA levels were significantly higher in LC compared with LSSC, 24 h postoperatively (P = 0.021). No significant changes over time in the UA levels in both groups (LSSC: P = 0.056, LC: P = 0.205). CONCLUSIONS: LSSC is associated with increased oxidative stress compared with LC. Further studies are needed to confirm these results.

Pathophysiological role and clinical significance of lipoprotein-associated phospholipase A2 (Lp-PLA2) bound to LDL and HDL.

Lipoprotein-associated phospholipase A2 (Lp-PLA2), also named as platelet-activating factor (PAF)-acetylhydrolase, exhibits a Ca2+-independent phospholipase A2 activity and catalyzes the hydrolysis of the ester bond at the sn-2 position of PAF and oxidized phospholipids (oxPL). These phospholipids are formed under oxidative and inflammatory conditions, and may play important roles in atherogenesis. The vast majority of plasma Lp-PLA2 mass binds to low-density lipoprotein (LDL) while a smaller amount is associated with high-density lipoprotein (HDL). Lp-PLA2 is also bound to lipoprotein (a) [Lp(a)], very low-density lipoprotein (VLDL) and remnant lipoproteins. Several lines of evidence suggest that the role of plasma Lp-PLA2 in atherosclerosis may depend on the type of lipoprotein particle with which this enzyme is associated. Data from large Caucasian population studies have supported plasma Lp-PLA2 (primarily LDL-associated Lp-PLA2) as a cardiovascular risk marker independent of, and additive to, traditional risk factors. On the contrary, the HDL-associated Lp-PLA2 may express antiatherogenic activities and is also independently associated with lower risk for cardiac death. The present review presents data on the biochemical and enzymatic properties of Lp-PLA2 as well as its structural characteristics that determine the association with LDL and HDL. We also critically discuss the possible pathophysiological and clinical significance of the Lp- PLA2 distribution between LDL and HDL in human plasma, in view of the results of prospective epidemiologic studies on the association of Lp-PLA2 with future cardiovascular events as well the recent studies that evaluate the possible effectiveness of specific Lp-PLA2 inhibitors in reducing residual cardiovascular risk.

Effect of switch to the highest dose of rosuvastatin versus add-on-statin fenofibrate versus add-on-statin nicotinic acid/laropiprant on oxidative stress markers in patients with mixed dyslipidemia.

INTRODUCTION: Oxidative stress plays an important role in atherosclerosis. Both F2-isoprostane (8-iso-PGF2a) and oxidized low-density lipoprotein (ox-LDL) have emerged as biomarkers of oxidative stress and have been proposed as useful biomarkers that could potentially be used as indicators of cardiovascular disease. METHODS: This is a prespecified analysis of a prospective, randomized, open-label, blinded endpoint (PROBE) study (ClinicalTrials.gov identifier: NCT01010516). Patients (N = 100) with mixed dyslipidemia on a standard statin dose (10-40 mg simvastatin or 10-20 mg atorvastatin or 5-10 mg rosuvastatin) who had not achieved lipid targets were randomized to switch to the highest dose of rosuvastatin (40 mg/day) or to add-on-statin extended release nicotinic acid (ER-NA)/laropiprant (LRPT) (1000/20 mg/day for the first 4 weeks followed by 2000/40 mg/day for the next 8 weeks) or to add-on-statin micronized fenofibrate (200 mg/day) for a total of 3 months. Levels of plasma and urine F2-isoprostane and plasma ox-LDL were assessed at baseline and 3 months later. RESULTS: Plasma F2-isoprostane levels decreased similarly in all groups. On the other hand, both ox-LDL and urine F2-isoprostane levels decreased similarly in the add-on ER-NA/LRPT and rosuvastatin monotherapy group, while a less pronounced decrease was observed in the add-on fenofibrate group. CONCLUSIONS: All treatment interventions reduced the concentration of the assessed oxidative stress markers, but the reduction was more pronounced in the add-on ER-NA/LRPT and rosuvastatin monotherapy groups, compared with add-on fenofibrate. Specifically designed studies should address the abovementioned risk factors modulation in terms of cardiovascular risk.

Lipoprotein-associated phospholipase A2 and arterial stiffness evaluation in patients with inflammatory bowel diseases.

BACKGROUND AND AIMS: The association between inflammatory bowel diseases (IBD) and cardiovascular disease (CVD) remains equivocal. Arterial stiffness, as assessed by pulse wave velocity (PWV), and lipoprotein-associated phospholipase A2 (Lp-PLA2) are surrogates of CVD risk. AIM: The aim of this study was to assess carotid-femoral PWV and Lp-PLA2 in patients with IBD without history of CVD. METHODS: Established CVD risk factors, IBD characteristics, PWV and Lp-PLA2 activity were assessed in 44 patients with IBD, 29 with Crohn's disease (CD) and 15 with ulcerative colitis (UC), and 44 matched controls. RESULTS: IBD patients had lower total and low density lipoprotein cholesterol (LDL-C) levels. There was no difference in PWV between patients and controls (6.8 vs. 6.4m/s), but patients with CD had higher PWV compared to those with UC (7 vs. 6.3m/s; p=0.044), and to controls. Smoking rates were significantly higher among CD patients. Factors associated with PWV were age, mean arterial pressure and smoking. Lp-PLA2 activity was significantly lower in patients with IBD (46.8 vs. 53.9 nmol/mL/min; p=0.011). There was no difference in Lp-PLA2 between CD and UC patients. LDL-C was the only significant predictor of Lp-PLA2. CONCLUSIONS: Our study showed lower Lp-PLA2 activity in patients with IBD compared with controls, reflecting lower LDL-C in the former. There was no difference in PWV between the two groups. Arterial stiffness was higher in patients with CD, which is likely related to higher smoking rates. These findings challenge a possible association between IBD and CVD, but further studies are required.