Does Yogurt Enriched with Platelet-Activating Factor Inhibitors from Olive Oil By-Products Affect Gut Microbiota and Faecal Metabolites in Healthy Overweight Subjects? (A randomized, parallel, three arm trial.)

OBJECTIVE

The effect of the daily consumption of a low-fat yogurt (150 g) enriched with Platelet-Activating Factor receptor (PAF-R) antagonists, or the plain one, on gut microbiota and faecal metabolites was investigated in healthy overweight subjects.

METHODS

A randomized, three-arm, double-blind, placebo-controlled, parallel-group study was performed that lasted 8 weeks. Blood and stools were collected and analyzed before and after the intervention.

RESULTS

Our findings revealed that the intake of the enriched yogurt resulted in a significant increase in the levels of Bifidobacterium spp., Clostridium perfringens group and Firmicutes-to-Bacteroidetes (F/B) ratio. On the other hand, a significant increase in the levels of Lactobacillus and C. perfringens group was detected after the intake of the plain yogurt. The increase in the levels of C. perfringens group was inversely associated with the plasma catabolic enzyme of PAF, namely LpPLA2 (lipoprotein-associated phospholipase A2), a cardiovascular risk marker that has been linked with inflammation and atherosclerosis. Moreover, in the enriched with PAF-R antagonists yogurt group, the increased levels of C. perfringens group were also associated with lower PAF action assessed as ex vivo human platelet-rich plasma (PRP) aggregation. Additionally, a higher % increase in molar ratio of Branched Short Chain Fatty Acids (BSCFAs) was detected for both yogurt groups after the 8 week-intervention compared to control. The consumption of the enriched yogurt also resulted in a significant drop in faecal caproic levels and a trend for lower ratio of butyrate to total volatile fatty acids (VFAs) compared to baseline levels.

CONCLUSION

Yogurt consumption seems to favorably affect gut microbiota while its enrichment with PAF-R antagonists from olive oil by-products, may provide further benefits in healthy overweight subjects.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov (NCT02259205).

Food Compass Score predicts incident cardiovascular disease: The ATTICA cohort study (2002-2022)

BACKGROUND

The Food Compass Score (FCS) is a novel nutrient profiling system, which evaluates food and diet quality. The present study aimed to prospectively assess the relationship of FCS with short-term (10 years) and long-term (20 years) cardiovascular disease (CVD) incidence and to explore whether this relationship is modified by long-term adherence to a Mediterranean type diet (MTD).

METHODS

Volunteers of the ATTICA cohort study, with complete data for the calculation of FCS and incident CVD were included (n = 759). Development of CVD was determined at 10 and 20 years after baseline. Dietary intake was assessed through a validated food frequency questionnaire. The FCS was calculated for each participant based on the published algorithm. Long-term adherence to a MTD was evaluated through MedDietScore.

RESULTS

FCS was inversely associated with CVD incidence (hazard ratio [HR] for 20-year follow-up = 0.97, 95% confidence interval [CI] = 0.95-0.99; HR for 10-year follow-up = 0.98, 95% CI = 0.96-1.01) in the total sample, as well as in those with a high baseline adherence to a MTD (HR for 20-year follow-up = 0.96, 95% CI = 0.93-0.99; HR for 10-year follow-up = 0.98, 95% CI = 0.95-1.02). FCS was also inversely associated with CVD risk in those who went away from the MTD (HR = 0.97, 95% CI = 0.96-0.99).

CONCLUSIONS

FCS, a novel tool for assessing overall diet quality, was also found to be useful in identifying potential CVD candidates in a long-term period, even in populations with good background dietary habits, such as those following a MTD.

Associations of phase angle with platelet-activating factor metabolism and related dietary factors in healthy volunteers

Introduction

Phase angle (PA) is derived from bioelectrical impedance analysis (BIA). It reflects cell membrane function and decreases in disease. It is affected by inflammation, oxidative stress, and diet. Platelet-activating factor (PAF) is a potent inflammatory lipid mediator. Its levels, along with the activity of its metabolic enzymes, including CDP-choline:1-alkyl-2-acetyl-sn-glycerol-cholinephosphotransferase, acetyl-CoA:lyso-PAF-acetyltransferases, and PAF-AH/Lp-PLA2 are also related to dietary factors, such as the dietary antioxidant capacity (DAC). The aim of the study was to estimate whether the PAF metabolic circuit and related dietary factors are associated with PA in healthy volunteers.

Methods

In healthy subjects, PAF, its metabolic enzyme activity, and erythrocyte fatty acids were measured, while desaturases were estimated. Food-frequency questionnaires and recalls were used, and food groups, macronutrient intake, MedDietScore, and DAC were assessed. Lifestyle and biochemical variables were collected. DXA and BIA measurements were performed.

Results

Lp-PLA2 activity was positively associated with PA (rho = 0.651, p < 0.001, total population; rho = 0.780, p < 0.001, women), while PAF levels were negatively associated with PA only in men (partial rho = -0.627, p = 0.012) and inversely related to DAC. Estimated desaturase 6 was inversely associated with PA (rho = -0.404, p = 0.01, total sample). Moreover, the DAC correlated positively with PA (rho = 0.513, p = 0.03, women). All correlations were adjusted for age, body mass index, and sex (if applicable).

Conclusion

PA is associated with PAF levels and Lp-PLA2 activity in a gender-dependent fashion, indicating the involvement of PAF in cell membrane impairment. The relationship of PA with DAC suggests a protective effect of antioxidants on cellular health, considering that antioxidants may inhibit PAF generation.

Food Compass Score and its association with inflammatory markers and homocysteine in cardiovascular disease-free adults: a cross-sectional analysis of the ATTICA epidemiological study

BACKGROUND/OBJECTIVES

Several nutrient profiling systems have been developed to assist in food choices and policy. Food Compass Score (FCS) is a novel holistic food score assessing 54 parameters. The aim was to assess the relation of FCS with inflammatory and lipid markers in cardiovascular disease-free volunteers.

SUBJECTS/METHODS

Information from the ATTICA epidemiological study participants, with complete data on lipid, inflammatory markers and dietary intake were studied (n = 1018). C-reactive protein (CRP) and amyloid A were determined by immunonephelometry, fibrinogen by nephelometry, homocysteine by fluorometry, while tumor necrosis factor-a (TNF-a), interleukin-6 (IL-6), adiponectin and leptin were determined by ELISA in fasting blood samples. Dietary intake was assessed through a semi-quantitative validated food frequency questionnaire. Each food was assigned a FCS value from the published values and then individual's FCS values were calculated.

RESULTS

Mean FCS was 56 (standard deviation: 5.7) and it was similar in men and women. FCS was inversely correlated with age (r = -0.06, p = 0.03). In multiple linear regression models, FCS was inversely associated with CRP (-0.03, 0.01), TNF-a (-0.04, 0.01), amyloid A (-0.10, 0.04) and homocysteine (-0.09, 0.04) (b coefficients, standard errors, all p < 0.05) and was not associated with IL-6, fibrinogen, adiponectin, leptin, or lipids levels (all p > 0.05).

CONCLUSIONS

The inverse correlations of the FCS with inflammatory markers suggest that a diet containing foods with high FCS might be protective against inflammation process. Our results support the usefulness of the FCS, but future studies should evaluate its relation to cardiovascular and other inflammation-related chronic diseases.

Protective Effect of Olive Oil Microconstituents in Atherosclerosis: Emphasis on PAF Implicated Atherosclerosis Theory

Atherosclerosis is a progressive vascular multifactorial process. The mechanisms underlining the initiating event of atheromatous plaque formation are inflammation and oxidation. Among the modifiable risk factors for cardiovascular diseases, diet and especially the Mediterranean diet (MedDiet), has been widely recognized as one of the healthiest dietary patterns. Olive oil (OO), the main source of the fatty components of the MedDiet is superior to the other "Mono-unsaturated fatty acids containing oils" due to the existence of specific microconstituents. In this review, the effects of OO microconstituents in atherosclerosis, based on data from in vitro and in vivo studies with special attention on their inhibitory activity against PAF (Platelet-Activating Factor) actions, are presented and critically discussed. In conclusion, we propose that the anti-atherogenic effect of OO is attributed to the synergistic action of its microconstituents, mainly polar lipids that act as PAF inhibitors, specific polyphenols and α-tocopherol that also exert anti-PAF activity. This beneficial effect, also mediated through anti-PAF action, can occur from microconstituents extracted from olive pomace, a toxic by-product of the OO production process that constitutes a significant ecological problem. Daily intake of moderate amounts of OO consumed in the context of a balanced diet is significant for healthy adults.

Selenium, Selenoproteins and 10-year Cardiovascular Risk: Results from the ATTICA Study

BACKGROUND

Selenium (Se) is an essential trace element that is involved in several pathophysiological functions. The relationship of Se with cardiovascular disease remains inconclusive, especially regarding the role of different selenospecies.

OBJECTIVE

The present study assessed the levels of Se distribution in plasma selenoproteins, namely glutathione peroxidase 3 (GPx3), selenoprotein P (SelP) and selenoalbumin (SeAlb) and total Se in selenoproteins in relation to 10-year cardiovascular risk in the ATTICA prospective study.

METHODS

A sub-sample from the ATTICA Study's database, consisting of 278 subjects (114 women and 164 men) with data on Se and selenoproteins levels, was considered. SeGPx3, SelP, and SeAlb in human plasma were simultaneously determined by high-performance liquid chromatography (HPLC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) at baseline. The duration of the follow-up was 8.74 ±2.36 years (mean± standard deviation) and cardiovascular outcomes were recorded. Cox proportional hazards models were applied with total Se or selenoprotein Se as independent variables adjusted for several covariates.

RESULTS

Total Se in selenoproteins was positively related to 10-year relative risk of cardiovascular disease (Hazard Ratios of 3rd vs 2nd tertile 10.02, 95% CI:1.15, 92.34). Subjects with high Se but low SeGPx3, as identified by discordant percentiles in the distribution of SeGPx3 and Se, had a higher cardiovascular risk.

CONCLUSION

The differentiated effects of circulating selenoproteins on cardiovascular disease risk in the present study, suggest the importance of redox regulation by specific selenoproteins.

Is there an interplay between the SARS-CoV-2 spike protein and Platelet-Activating factor?

Previous publications have reported a potent effect of COVID-19 on platelet function and that the Spike protein enhances washed human platelet aggregation induced by various agonists. This study aims to evaluate whether mRNA vaccination for COVID-19 affects human platelet-rich plasma (hPRP) aggregation response, whether a recombinant Spike protein modulates PAF-induced aggregation in hPRP and in washed rabbit platelets (WRP), and to investigate the effect of recombinant Spike protein on the PAF production in the U-937 cell line. Our results showed that PRP from vaccinated individuals exhibited ex vivo lower EC₅₀ values in response to PAF, ADP, and collagen. Platelet incubation with the Spike protein alone did not induce aggregation either in hPRP or in WRP, but resulted in augmentation of in vitro PAF-induced aggregation in hPRP from non-vaccinated individuals and in WRP. When PRP from vaccinated individuals was incubated with the Spike protein and PAF was subsequently added, elimination of the secondary wave of the biphasic aggregation curve was recorded compared with the aggregation induced by PAF alone. Collagen-induced in vitro aggregation was dose-dependently reduced when platelets were pre-incubated with the Spike protein in all tested aggregation experiments. Stimulation of U-937 by the Spike protein induced an increase in intracellular PAF production accompanied by elevation of the activities of all three PAF biosynthetic enzymes. In conclusion, since the Spike protein appears to modulate PAF production and activity, the use of compounds that act as PAF inhibitors, could be considered at least in mild cases of patients infected with SARS-CoV-2.

Consumption of Farmed Fish, Fed with an Olive-Pomace Enriched Diet, and Its Effect on the Inflammatory, Redox, and Platelet-Activating Factor Enzyme Profile of Apparently Healthy Adults: A Double-Blind Randomized Crossover Trial

A fish-rich diet has a beneficial effect on cardiovascular health. The platelet activating factor (PAF) is involved in the development of atherosclerosis, and in vitro results support the regulating action of bioactive nutrients on PAF metabolism. The purpose of this study is to examine whether the consumption of farmed fish fed with an olive-pomace enriched diet (EF) affects PAF metabolism and the markers of inflammation and oxidative stress compared to the consumption of conventionally fed farmed fish (CF). Thirty apparently healthy adults completed a randomized double-blind crossover trial, during which they consumed both CF and EF twice a week for 8 weeks with a six-week washout period in between. The activities of PAF acetylhydrolase (PAF-AH), lysoPAF acetyltransferase (lysoPAF-AT), DTT-insensitive CDP-choline: 1-alkyl-2-acetyl-sn-glycerol-choline-phosphotransferase (PAF-CPT) in leukocytes, and lipoprotein-associated phospholipase A₂ (LpPLA₂) in serum were determined. The quantities of interleukin-6 (IL-6), high sensitivity C-reactive protein (hsCRP), oxidized LDL (ox-LDL), thiobarbituric acid-reactive substances (TBARS), and glutathione peroxidase (GPx), as well as the serum oxidation, were also determined. Both types of fish exerted similar effects as there were no statistically significant differences between the two interventions except for an elevated PAF-CPT and reduced arachidonic acid (AA) in the red blood cell (RBC) membrane lipids after the EF intake.

The effect of moderate wine consumption on cytokine secretion by peripheral blood mononuclear cells: A randomized clinical study in coronary heart disease patients

Many studies conclude that wine consumption is related to lower risk for cardiovascular diseases partially through the amelioration of inflammatory biomarkers. The aim of the present study was to examine the effects of wine consumption on the inflammatory response and to compare these effects with the consumption of similar amount of alcohol without the wine micro-constituents in cardiovascular disease patients. Therefore, a randomized, single-blind, controlled, three-arm parallel intervention study was designed. Cardiovascular disease patients were randomly assigned to one of the three groups. In Group A participants consumed no alcohol, in Group B (ethanol group) and Group C (wine group) participants consumed 27 g of alcohol per day. Biological samples were collected at the beginning, on the 4th and 8th week and several biomarkers were measured. Peripheral blood mononuclear cells that were isolated from patients were incubated under basal and inflammatory conditions for 4 and 24 h and the secretion of interleukin 1β (IL-1β) and tumor necrosis factor α (TNFα) was measured. No significant difference was observed among the three groups before the initiation or during the intervention in the most soluble biomarkers. Higher TNFα secretion by peripheral blood mononuclear cells was observed at basal conditions in the ethanol group both at 4 and 24 h of incubation versus baseline secretion. Furthermore, lower secretion of the ΤNFα was observed after 8 weeks of intake in the wine group versus the ethanol group, both at 4 and 24 h of incubation. In conclusion, the light to moderate wine consumption for 8 weeks revealed an attenuation of the ethanol consumption effect on cytokine secretion at basal conditions from the patients' peripheral blood mononuclear cells.

Association of PAF and its metabolic enzymes with GGT and the Fatty Liver Index in healthy volunteers

BACKGROUND

Platelet-activating factor (PAF) is a lipid inflammatory mediator implicated in liver disease. Its main biosynthetic enzymes are cytidine diphosphate (CDP)-choline:1-alkyl-2-acetyl-sn-glycerol-cholinephosphotransferase (PAF-CPT) and acetyl-coenzyme A: lyso-PAF-acetyltransferases (Lyso-PAF-AT), while PAF acetylhydrolase (PAF-AH) and lipoprotein-associated phospholipase A2 (Lp-PLA2) degrade PAF.

OBJECTIVE

To explore the relation of PAF metabolism with liver diseases and non-alcoholic fatty liver disease, as reflected by the fatty liver index (FLI).

METHODS

In 106 healthy volunteers, PAF concentration, the activity of its metabolic enzymes, and gamma-glutamyl transferase (GGT) were measured in whole blood, leukocytes, and serum, respectively, and the FLI was calculated. Partial correlations and linear regression models were used.

RESULTS

In males, serum GGT activity was positively correlated with abdominal fat (as assessed by analysis of a manually defined region of interest in dual-energy X-ray absorptiometry), triacylglycerols, bound-PAF, and Lp-PLA2, while the FLI was positively correlated with Lp-PLA2 activity. In females, serum GGT activity was negatively associated with high-density lipoprotein cholesterol (HDL-C) (age-adjusted correlations, all p<0.05). Lp-PLA2 was a significant determinant of serum GGT activity in males after controlling for age, low-density lipoprotein cholesterol (LDL-C), and abdominal fat. The addition of bound-PAF in the model significantly increased the explained variance of serum GGT activity (total variance explanation 30%).

CONCLUSION

Bound-PAF and Lp-PLA2 activity predicted serum GGT activity, while Lp-PLA2 was also related to FLI. Our findings shed light on the metabolic pathways linking Lp-PLA2 to other atherosclerosis and/or oxidative markers, such as HDL-C, LDL-C, GGT, and FLI, and underline the important role of PAF.

Consumption of Enriched Yogurt with PAF Inhibitors from Olive Pomace Affects the Major Enzymes of PAF Metabolism: A Randomized, Double Blind, Three Arm Trial

Platelet-activating factor (PAF), a proinflammatory lipid mediator, plays a crucial role in the formation of the atherosclerotic plaque. Therefore, the inhibition of endothelium inflammation by nutraceuticals, such as PAF inhibitors, is a promising alternative for preventing cardiovascular diseases. The aim of the present study was to evaluate the impact of a new functional yogurt enriched with PAF inhibitors of natural origin from olive oil by-products on PAF metabolism. Ninety-two apparently healthy, but mainly overweight volunteers (35-65 years) were randomly allocated into three groups by block-randomization. The activities of PAF's biosynthetic and catabolic enzymes were measured, specifically two isoforms of acetyl-CoA:lyso-PAF acetyltransferase (LPCATs), cytidine 5'-diphospho-choline:1-alkyl-2-acetyl-sn-glycerol cholinephosphotransferase (PAF-CPT) and two isoforms of platelet activating factor acetylhydrolase in leucocytes (PAF-AH) and plasma (lipoprotein associated phospholipase-A₂, LpPLA₂). The intake of the enriched yogurt resulted in reduced PAF-CPT and LpPLA₂ activities. No difference was observed in the activities of the two isoforms of lyso PAF-AT. In conclusion, intake of yogurt enriched in PAF inhibitors could favorably modulate PAF biosynthetic and catabolic pathways.

Micronutrients, Phytochemicals and Mediterranean Diet: A Potential Protective Role against COVID-19 through Modulation of PAF Actions and Metabolism

The new coronavirus disease 2019 (COVID-19) pandemic is an emerging situation with high rates of morbidity and mortality, in the pathophysiology of which inflammation and thrombosis are implicated. The disease is directly connected to the nutritional status of patients and a well-balanced diet is recommended by official sources. Recently, the role of platelet activating factor (PAF) was suggested in the pathogenesis of COVID-19. In the present review several micronutrients (vitamin A, vitamin C, vitamin E, vitamin D, selenium, omega-3 fatty acids, and minerals), phytochemicals and Mediterranean diet compounds with potential anti-COVID activity are presented. We further underline that the well-known anti-inflammatory and anti-thrombotic actions of the investigated nutrients and/or holistic dietary schemes, such as the Mediterranean diet, are also mediated through PAF. In conclusion, there is no single food to prevent coronavirus Although the relationship between PAF and COVID-19 is not robust, a healthy diet containing PAF inhibitors may target both inflammation and thrombosis and prevent the deleterious effects of COVID-19. The next step is the experimental confirmation or not of the PAF-COVID-19 hypothesis.

Effect of Differently Fed Farmed Gilthead Sea Bream Consumption on Platelet Aggregation and Circulating Haemostatic Markers among Apparently Healthy Adults: A Double-Blind Randomized Crossover Trial

Fish consumption beneficially affects coagulation markers. Few dietary intervention studies have investigated differently fed farmed fish against these cardio-metabolic risk factors in humans. This double-blind randomized crossover trial evaluated differently fed farmed gilthead sea bream consumption against platelet aggregation and circulating haemostatic markers among apparently healthy adults. Subjects aged 30-65 years, with a body mass index 24.0-31.0 kg/m², consuming less than 150 g cooked fish per week, were recruited in Attica, Greece. Participants were randomized (n = 38, 1:1) to one of two sequences; consumption of fish fed with fish oil diet (conventional fish, CF)/fish fed with olive pomace-enriched diet (enriched fish, EF) versus EF/CF. The primary outcomes were ex vivo human platelet aggregation and circulating plasminogen activator inhibitor-1 (PAI-1) and P-selectin (sP-selectin) concentrations. EF consumption had no significant effect on platelet sensitivity or haemostatic markers compared to CF. Platelet sensitivity to platelet-activating factor (PAF) decreased after CF consumption during the second period (p < 0.01). Plasma PAI-1 and sP-selectin concentrations increased after CF consumption during both periods (p < 0.01 for both). Based on current findings, consumption of enriched farmed gilthead sea bream had no greater effect on coagulation markers in adults compared to the conventionally fed fish.

Associations between red blood cells fatty acids, desaturases indices and metabolism of platelet activating factor in healthy volunteers

INTRODUCTION

Platelet-activating-factor is an inflammatory lipid mediator. Key enzymes of its biosynthesis are CDP-choline:1-alkyl-2-acetyl-sn-glycerol-cholinephosphotransferase (PAF-CPT) and acetyl-CoA:lyso-PAF-acetyltransferases (Lyso-PAF-AT) while PAF-AH/Lp-PLA₂ degrade PAF. The interplay between PAF and fatty acids metabolism was explored.

MATERIAL AND METHODS

In a healthy population, PAF levels, its metabolic enzymes activity and RBC fatty acids were measured while desaturases indices (D) were estimated. A principal component analysis was also applied to assess patterns of RBC fatty acids.

RESULTS

SFA were related to increased PAF biosynthesis and decreased Lp-PLA₂ only in women. MUFA were inversely associated with PAF biosynthesis and positively with Lp-PLA₂. Omega-6 fatty acids were positively correlated only with PAF-CPT while no significant correlations were observed with n3 fatty acids. D6 index was positively related with PAF biosynthetic enzymes and inversely with Lp-PLA₂ while D9 correlated positively with Lp-PLA_2. The pattern of high MUFA and low n6 was associated with reduced PAF biosynthesis and/or increased catabolism in both sexes.

CONCLUSION

The role of fatty acids in amplifying or reducing inflammation seems to be also reflected in PAF metabolism.

Mediterranean diet is inversely associated with steatosis and fibrosis and decreases ten-year diabetes and cardiovascular risk in NAFLD subjects: Results from the ATTICA prospective cohort study

BACKGROUND AND AIMS

We assessed the association of Mediterranean diet with NAFLD and their interaction in predicting ten-year diabetes onset and first fatal/non-fatal cardiovascular disease (CVD) incidence.

METHODS

The ATTICA prospective observational study in Athens, Greece included 1,514 men and 1,528 women (>18 years old) free-of-CVD at baseline. Liver steatosis and fibrosis indices were calculated. Mediterranean diet adherence was assessed through MedDietScore. At the ten-year follow-up visit, CVD evaluation was performed in an a priori specified subgroup of n = 2,020 participants and diabetes onset in n = 1,485 free-of-diabetes participants.

RESULTS

MedDietScore was inversely associated with steatosis and fibrosis; e.g. in the case of the TyG index the Odds Ratio (OR) of the 3rd vs. 1st MedDietScore tertile was = 0·53, [95% Confidence Interval (95% CI) (0·29, 0·95)] and the associations persisted in multi-adjusted models. NAFLD predicted incident diabetes prospectively over a ten year period [HR = 1·87, 95% CI (0·75, 4·61)] and the association remained significant only in subjects with low MedDietScore (below median) whereas diabetes onset among subjects with higher MedDietScore was not influenced by NAFLD. Similarly, NAFLD predicted CVD [Hazard Ratio (HR) = 3·01, 95%CI(2·28, 3·95)]; the effect remained significant only in subjects with MedDietScore below median [HR = 1·38, 95% CI (1·00, 1·93)] whereas it was essentially null [HR = 1·00,95% CI (0·38, 2·63)] among subjects with higher score. Mediation analysis revealed that adiponectin and adiponectin-to-leptin ratio were the strongest mediators.

CONCLUSIONS

We report an inverse association between Mediterranean diet and NAFLD. Mediterranean diet protected against diabetes and CVD prospectively among subjects with NAFLD.

COVID-19, microthromboses, inflammation, and platelet activating factor

Recent articles report elevated markers of coagulation, endothelial injury, and microthromboses in lungs from deceased COVID-19 patients. However, there has been no discussion of what may induce intravascular coagulation. Platelets are critical in the formation of thrombi and their most potent trigger is platelet activating factor (PAF), first characterized by Demopoulos and colleagues in 1979. PAF is produced by cells involved in host defense and its biological actions bear similarities with COVID-19 disease manifestations. PAF can also stimulate perivascular mast cell activation, leading to inflammation implicated in severe acute respiratory syndrome (SARS). Mast cells are plentiful in the lungs and are a rich source of PAF and of inflammatory cytokines, such as IL-1β and IL-6, which may contribute to COVID-19 and especially SARS. The histamine-1 receptor antagonist rupatadine was developed to have anti-PAF activity, and also inhibits activation of human mast cells in response to PAF. Rupatadine could be repurposed for COVID-19 prophylaxis alone or together with other PAF-inhibitors of natural origin such as the flavonoids quercetin and luteolin, which have antiviral, anti-inflammatory, and anti-PAF actions.

Coronavirus 2019, Microthromboses, and Platelet Activating Factor

Recent articles have reported elevated markers of coagulation, endothelial injury, and microthromboses in lungs from deceased patients with coronavirus 2019 (COVID-19). Platelets are critical in the formation of thrombi, and their most potent trigger is platelet activating factor (PAF). PAF is produced by cells involved in host defense, and its biological actions bear similarities with COVID-19 disease manifestations, including pulmonary microthromboses and inflammation, possibly via activation of mast cells. The histamine1 receptor antagonist rupatadine was developed to have anti-PAF activity and inhibits activation of human mast cells in response to PAF. Rupatadine could be repurposed for COVID-19 prophylaxis.

The French paradox three decades later: Role of inflammation and thrombosis

Although, three decades have pasted from the introduction of "French Paradox", is still an issue for debate. Epidemiology supports the J-shaped relationship between wine consumption and vascular events as well as cardiovascular mortality with a maximum protection at 21 g of alcohol consumption in the form of wine per day. Nevertheless, the aforementioned studies have used an observational design that raises concerns about potential confounding. Randomized clinical studies may provide data to end the controversy and in parallel with in vitro experiments to elucidate the mechanisms by which wine affects cardiovascular disease. In this concept, this review aims to address the presence of bioactive wine micro constituents, their potential mechanisms of action and also to summarize the cardio-protective effects of wine intake based on clinical trials. The role of wine micro-constituents in inflammation and haemostasis is discussed in detail.

Evaluation of anti-platelet activity of grape pomace extracts

Platelets aggregation plays a crucial role in atherothrombosis. Therefore, the aim of the present study was to examine the anti-platelet activity of winery by-products extracts, to find the most potent one and to be further analyzed in order to be used for food fortification. For this purpose, grape pomace from four red varieties was extracted with four solvents of different polarity. The extracts' phenolic content, antioxidant capacity and their ability to inhibit human platelet aggregation against PAF, ADP, TRAP were determined by Light Transmission Aggregometry. The ethanolic extract was further analyzed concerning its anti-platelet effect and its chemical composition by LC-MS/MS and GC-MS. The ethanolic and Bligh-Dyer water phase extracts showed the highest phenolic compounds/anthocyanin content and the best antioxidant activity. However, the most potent inhibition of platelet aggregation was revealed by ethanol extracts, followed by the Bligh-Dyer lipoid phase extracts. Ethanolic extract, found to contain micro-constituents such as phospho-compounds, phenolic compounds and fatty acids. The most abundant phenolic compounds were catechin, epicatechin and quercetin and the most abundant fatty acids were linoleic acid (C18:2n6), linolenic acid (C18:3n3) and palmitic acid (C16:0). Ethanolic extract was capable of inhibiting platelets aggregation in a wide range of agonist concentrations and it also seems that its action is sustained when platelets from coronary heart disease patient were used. Ethanol extract of winery by-products exerts a potent anti-platelet effect and its valorization could lead to the production of functional foods with cardioprotective properties.

Mining possible associations of faecal A. muciniphila colonisation patterns with host adiposity and cardiometabolic markers in an adult population

We aimed to evaluate colonisation patterns of Akkermansia muciniphila in a Greek adult population and to investigate model-adjusted associations of A. muciniphila with host adiposity and cardiometabolic markers. Participants (n=125) underwent anthropometric, dietary, physical activity and lifestyle evaluation. Blood sampling for determination of blood lipid indices, glucose metabolism, adiponectin, lipoprotein-associated phospholipase A2 (Lp-PLA2), inflammation and oxidative stress parameters was also performed. Stool A. muciniphila presence and levels were determined by quantitative PCR and subjects were grouped based on bimodal distribution of levels (Low vs High). A. muciniphila was detected in 88.6% of participants. Overweight/obese (OW/OB) subjects were more prone in low bimodal levels of A. muciniphila compared to normal-weight (NW) individuals (58.75 vs 27.59%, P=0.004), with a 4-time greater likelihood after multi-adjusted logistic regression analysis (P=0.016). Levels of A. muciniphila were negatively associated with total cholesterol/high-density lipoprotein cholesterol (TC/HDL-C) ratio (log10:-0.009±0.004, P=0.033), whereas detection of this bacterium was negatively associated with both TC/HDL-C ratio (log10: -0.049±0.023, P=0.036) and low-density lipoprotein cholesterol/HDL-C ratio (-0.407±0.176, P=0.023). Furthermore, low bimodal levels of A. muciniphila were positively associated with fasting blood glucose (log10: 0.018±0.009, P=0.037). In terms of inflammation markers, levels of A. muciniphila were positively associated with soluble cluster of differentiation-14 (sCD14) (log10: 0.012±0.004, P=0.003) and faecal detection of this bacterium had a positive association with anti-inflammatory interleukin 10 levels (log10: 0.325±0.131, P=0.015). In addition, A. muciniphila levels were positively associated with total adiponectin (log10: 0.046±0.015, P=0.002), whereas low bimodal levels of A. muciniphila had an inverse relationship with this blood marker (log10: -0.131±0.053, P=0.016). In conclusion, we confirmed the previously reported association of A. muciniphila with metabolic health for the first time in a Greek urban population; furthermore, we shed some light to novel atherosclerotic risk markers with rather unexplored connections with A. muciniphila colonisation patterns in human subjects.

Energy Intake and Plasma Adiponectin as Potential Determinants of Lipoprotein-Associated Phospholipase A2 Activity: A Cross-Sectional Study

Lipoprotein-associated phospholipase A₂ (Lp-PLA₂ ) is associated with increased risk of cardiovascular diseases (CVD) and type 2 diabetes mellitus. Lp-PLA₂ activity is positively associated with male sex, Caucasian race, the presence of metabolic syndrome (MetS) and low-density lipoprotein (LDL)-cholesterol, but it is negatively associated with high-density lipoprotein (HDL)-cholesterol. Associations with other cardiometabolic risk factors, inflammation markers, and lifestyle factors are few or inconsistent. We investigated potential determinants of Lp-PLA₂ activity among both nonmodifiable and modifiable CVD risk factors in a middle-aged Greek cohort without overt CVD. Two hundred eighty four subjects (159 men, 53 ± 9 years and 125 women 52 ± 9 years) participated in a cross-sectional study carried out during 2011-2012 in Athens, Attica. Cardiometabolic risk factors, inflammation markers, lifestyle factors, and Lp-PLA₂ activity were evaluated with established methods. The American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) criteria were used to define MetS. Lp-PLA₂ activity was not associated with MetS, but was associated with MetS components, markers of liver function, and macronutrient intake. Increased total energy intake was associated with increased Lp-PLA₂ activity (odds ratio, 95% confidence interval: 1.07, 1.01-1.14 and 1.10, 1.03-1.16 for the 4th and 3rd quartiles, respectively, compared to the 1st quartile) after adjustments for sex, pack-years of smoking, LDL-cholesterol, and statin treatment. Adiponectin tended to be inversely associated with Lp-PLA₂ activity (0.91, 0.82-1.00, and 4th versus 1st quartile). Our results suggested that total energy intake and adiponectin levels are potential determinants of Lp-PLA₂ activity.

Suppression of DNA/RNA and protein oxidation by dietary supplement which contains plant extracts and vitamins: a randomized, double-blind, placebo-controlled trial

Background

Excessive oxidative stress may impair bio-molecules and cellular function. Multi antioxidant supplementation is thought to be more effective than a single antioxidant probably through the synergistic or complementary action of natural substances that could enhance the prospective effect.

Methods

In order to estimate the effect of a plant extract based supplement in apparently healthy volunteers’ oxidative stress markers, a double-blind and placebo controlled intervention was performed. 62 apparently healthy volunteers, overweight with medium adherence to the Mediterranean diet, were recruited and randomly allocated into two intervention groups (supplement or placebo) for 8 weeks. Basic biochemical markers, oxidized LDL (oxLDL), resistance of serum in oxidation, protein carbonyls in serum and 8-isoprostane and DNA/RNA damage in urine were measured.

Results

No differentiation was observed in basic biochemical markers, in oxLDL levels as well as in serum resistance against oxidation, during intervention in the examined groups. A significant resistance regarding urine isoprostanes levels in the supplement group compared to the placebo one, was observed. Reduction on DNA/RNA damage and on protein carbonyls levels (almost 30% and 20% respectively, at 8 weeks) was detected in volunteers who consumed the supplement compared to the control group.

Conclusion

Consumption of plant extract based supplement seems to reduce DNA/RNA and protein oxidation and in less extent lipids peroxidation.

Trial registration

ClinicalTrials.gov Identifier for this study is: NCT02837107.

Biomarkers and Gene Polymorphisms in Members of Long- and Short-lived Families: A Longevity Study

Background

The influence of biomarkers in human lifespan has been investigated but with no clear results yet.

Materials and methods

Lipids, Uric Acid (UA), Adiponectin (ADIPOQ), Insulin-like Growth Factor (IGF-1), cholesteryl ester transfer protein (CETP) and angiotensin-converting enzyme (ACE) proteins, as well as CETP, ADIPOQ, insulin-like growth factor binding protein-3 (IGFBP3) and ACE-gene polymorphisms were evaluated in 149 Greek individuals. The Long-Lived Families (LON) (n=84) comprised of 3 generations: long-lived aged ≥90 years (P), offspring (FL1) and their grandchildren (FL2), while the Short-Lived Families (EAD) (n=65) where both parents died <75 years, comprised of 2 generations: middle-aged (FD1) and children (FD2).

Results

Serum CETP and IGF-1 levels were lower, whereas AdipoQ concentrations were higher in P compared with FL1 and FL2 members (CETP: p = 0.03 for both comparisons; IGF-1 p < 0.001 for both comparisons and ADIPOQ: p = 0.001 and p = 0.004, respectively). Furthermore, serum triglycerides, UA and glucose concentrations were higher in FD1 compared with FD2 subjects (p=0.001, 0.02 and ≤0.001, respectively). In FD2 and FL2, CETP levels were lower in individuals with B2B2 compared with B1B1 genotype (p=0.007). Additionally, ACE concentrations were higher in individuals with DD compared with II genotype in both Families (p=0.001). After adjustment for age and gender, CETP levels were lower in P and FL2 individuals with B2B2 compared with the B1B1 genotype (p=0.004 and 0.007, respectively).

Conclusion

Increase serum TGs, UA and GL concentrations were higher in the middle-aged individuals compared with their children in families independently of their lifespan. The serum adiponectin concentration was the highest in the oldest old individuals implying beneficial influence on lifespan. Independently of family's lifespan history, the youngest individuals with CETPB2B2 genotype, compared with individuals with CETPB1B1 genotypes, had lower serum CETP concentrations. The knowledge of the unfavourable gene(s)influencing human lifespan may be helpful in encouraging individuals to follow healthier lifestyle habits and better control their high-risk biomarkers.

Wine and its metabolic effects. A comprehensive review of clinical trials

The introduction of the term "French Paradox" motivated an extensive and in-depth research into health benefits of moderate wine consumption. The superiority of wine is thought to be attributed to its micro-constituents and consequent effort was made to isolate and identify these bioactive compounds as well as to elucidate the mechanisms of their action. Controlled trials offer more concrete answers to several raised questions than observational studies. Under this perspective, clinical trials have been implemented, mainly in healthy volunteers and rarely in patients, in order to investigate the acute or chronic effect of wine consumption on metabolism and physio-pathological systems, which are mainly associated with cardiovascular diseases. The aim of this review is to update the knowledge about the acute and long term effect of wine consumption on lipid and glucose/insulin metabolism as well as on the inflammatory and haemostatic systems, based on the reported data of controlled clinical trials. In conclusion, the most repeated result of wine consumption is on lipid metabolism, attributed mainly to ethanol, while wine micro-constituents seem to have an important role mainly in haemostatic and inflammatory/endothelial systems.

A low-dose, 6-week bovine colostrum supplementation maintains performance and attenuates inflammatory indices following a Loughborough Intermittent Shuttle Test in soccer players

PURPOSE

The aim of the study was to investigate the effect of a 6-week, low-dose bovine colostrum (BC) supplementation on exercise-induced muscle damage (EIMD) and performance decline in soccer players following the Loughborough Intermittent Shuttle Test (LIST) during a competitive season period.

METHODS

In a double-blind, randomized, placebo-controlled design, two groups of soccer players were allocated to a 3.2 g/day of whey protein (WP, N = 8) or BC (N = 10) and performed a pre- and a post-supplementation LIST. Maximum isometric voluntary contraction, squat jump (SQJ), countermovement jump, muscle soreness, blood cell counts, creatine kinase (CK), C-reactive protein (CRP) and interleukin-6 (IL-6) were monitored for 2, 24, 48, 72 h post-LIST.

RESULTS

LIST induced transient increases in leukocytes, granulocytes, CK, muscle soreness, CRP, IL-6 and declines in lymphocytes and performance indices. Supplementation resulted in a faster recovery of SQJ, CK and CRP compared to pre-supplementation kinetics (trial × time: p = 0.001, 0.056, 0.014, respectively) and lower incremental area under the curve (iAUC) for IL-6, only in the BC group [pre-: 31.1 (6.78-46.9), post-: 14.0 (-0.16 to 23.5) pg h/ml, p = 0.034]. Direct comparison of the two groups after supplementation demonstrated higher iAUC of SQJ [WP: -195.2 (-229.0 to (-52.5)), BC: -15.8 (-93.2 to 16.8) cm h, p = 0.034], a trend for lower iAUC of CK in the BC group [WP: 18,785 (4651-41,357), BC: 8842 (4807-14,802) U h/L, p = 0.081] and a significant intervention × time interaction for CRP (p = 0.038) in favor of BC.

CONCLUSIONS

Post-exercise EIMD may be reduced and performance better maintained by a low dose of BC administration following LIST in soccer players.

Fish consumption and cardiovascular disease related biomarkers: A review of clinical trials

The purpose of this review is to collect and compare fish intervention studies. Prospective studies have outlined the beneficial effect of frequent fish consumption on cardiovascular incidents that is attributed to n-3 fatty acids incorporated in fish, mainly eicosapentaenoic (EPA), and docosahexaenoic (DHA) acids. This outcome triggered clinical trials to examine the effect of either fish intake or consumption of n-3 fatty acids via capsules on biomarkers related to cardiovascular disease (CVD). The absence of a recent review focusing on clinical trials regarding fish intake and not n-3 fatty acids supplements rendered necessary the composition of this article. In total, 28 studies on healthy volunteers were found to meet the inclusion criteria. With EPA and DHA intake varying between 0.03 to 5 g per day, biomarkers, such as triglycerides, high-density lipoprotein and platelet aggregation, tended to ameliorate when daily intake exceeded 1 g per day, while the most common inflammatory marker, C-reactive protein, was not affected. In all, fish consumption gives promising results; yet fish micronutrients, total diet fat, as well as other dietary habits may also affect biomarkers. Therefore, all these factors should be considered in future clinical trials in order for one to draw more reliable conclusions.

The Production of Platelet-Activating Factor (PAF) during Hemodialysis with Cuprophane Membrane. Does the Calcium Concentration in the Dialysate Play Any Role on It?

There is evidence that PAF may be produced during hemodialysis (HD) mainly when using cuprophane membrane (CU). It is also known that PAF production is dependent on the amount of extracellular calcium (ECa2+). In the present study, we investigated the production of PAF during HD with CU as well as the role of the Ca2+ in the dialysate with respect to PAF production. Five hemodialyzed patients were studied in two consecutive HD sessions (the first performed using dialysate without Ca2+ and the second with a Ca2+ concentration of 3.25 mEq/L) and at different times during the sessions the circulating PAF levels as well as the leukocyte and platelet counts were measured. The results demonstrated that a) PAF was indeed produced during HD with CU, b) the highest PAF levels in blood were observed between 5 and 15 minutes from the beginning of HD, at which time the lowest circulating leukocyte and platelet count were measured and c) PAF levels in blood were inversely proportional to the Ca2+ concentration in the dialysate (with the exceptional case of the 15 minutes), although we expected the opposite results.

Amino acid profile and metabolic syndrome in a male Mediterranean population: A cross-sectional study

BACKGROUND AND AIMS

The metabolic syndrome (MetS) refers to a cluster of clinically relevant factors that increases the risk of cardiovascular diseases and all-cause mortality. Circulating levels of several amino acids and metabolites related to one-carbon metabolism have been associated with cardiometabolic risk factors and MetS. We aimed to identify the amino acid profile that is significantly associated with MetS among an all male Mediterranean population.

METHODS AND RESULTS

One hundred middle-aged men (54.6 ± 8.9 years) participated in a cross-sectional study carried out during 2011-2012. The International Diabetes Federation (IDF) criteria were used to define MetS. Fasting plasma levels of 20 common amino acids and 15 metabolites related to amino acid and one-carbon metabolism were measured using gas chromatography (GC-MS/MS) and liquid chromatography tandem mass spectrometry (LC-MS/MS). Principal components analysis was applied. Fifty-six participants fulfilled the IDF criteria for defining MetS. Five factors were extracted from the 35 measured metabolites. The branched-chain amino acids/aromatic amino acids (BCAA/AAA) related pattern and the glutamine/glycine/serine/asparagine (Gln/Gly/Ser/Asn) related pattern were significantly associated with MetS (odds ratio, 95% confidence interval; 6.41, 2.43-16.91, and 0.47, 0.23-0.96, respectively) after adjustment for age, current smoking status, physical activity level and medical treatment for hypertension, dyslipidaemia, type 2 diabetes mellitus. Further adjustment for liver function markers (i.e. glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, and γ-glutamyltransferase), and plasma adiponectin levels did not significantly affect the associations.

CONCLUSION

The BCAA/AAA pattern was positively associated, while the Gln/Gly/Ser/Asn pattern was inversely associated with established cardiometabolic risk factors and MetS. Plasma adiponectin levels or markers of liver function did not significantly affect these associations.

Anti-platelet effects of anti-glaucomatous eye drops: an in vitro study on human platelets

PURPOSE

Altered platelet aggregability has been implicated in the pathogenesis of glaucoma. This study aims to investigate the anti-platelet potential of intraocular pressure lowering drops, with the possibility of establishing it as an additional mechanism of anti-glaucomatous action.

MATERIALS AND METHODS

The anti-aggregating effects of a series of anti-glaucomatous eye drops were determined on human platelets in the platelet aggregation model, using four known aggregating factors (platelet activating factor [PAF], adenosine diphosphate [ADP], thrombin receptor-activating peptide [TRAP], and arachidonic acid [AA]).

RESULTS

Almost all of the tested samples inhibited platelet aggregation induced by PAF, ADP, TRAP, and AA, except for Alphagan, which did not demonstrate inhibition of ADP- and TRAP-induced aggregation at a wide range of concentrations. Trusopt, Betoptic, and Azarga eye drops were the most potent inhibitors of all four aggregating factors, while Alphagan was the least potent (P<0.05).

CONCLUSION

This study shows that anti-glaucomatous eye drops possess anti-platelet effects, and this was shown for the first time by experimenting on human platelets.

Reduced circulating adiponectin levels are associated with the metabolic syndrome independently of obesity, lipid indices and serum insulin levels: a cross-sectional study

BACKGROUND

Given the increasing rate of overweight and the burden of metabolic syndrome (MetS) on cardiovascular disease development, better understanding of the syndrome is of great importance. Therefore, the objectives were to examine whether interleukin-6 (IL-6) and adiponectin are associated with MetS, and whether this association is mediated by components of the MetS.

METHODS

During 2011-2012, 284 individuals (159 men, 53 ± 9 years, 125 women 52 ± 9 years) without cardiovascular disease, type 1 diabetes mellitus, high-grade inflammatory disease, living in the greater Athens area, Greece, participated in clinical examination. Adiponectin and IL-6 were measured in fasting plasma samples. MetS was defined according to the International Diabetes Federation (IDF) and the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) criteria.

RESULTS

MetS was present in 37 % (IDF) and 33 % (AHA/NHLBI) of the study population (P < 0.001). Adiponectin was inversely associated with MetS (odds ratio, 95 % confidence interval: 0.829, 0.762- 0.902 for MetS-IDF, and 0.840, 0.772- 0.914 for MetS-AHA/NHLBI). Body mass index (BMI), waist circumference, high density lipoprotein (HDL)-cholesterol, triglyceride and insulin concentration mediated the association between adiponectin and MetS-IDF (z-test, standard error, P-value: 2.898, 0.012, 0.004, for BMI; 2.732, 0.012, 0.006 for waist circumference; 2.388, 0.011, 0.017 for HDL-cholesterol; 2.163, 0.010, 0.031 for triglyceride; 2.539,  0.010,  0.011 for insulin). Similarly, BMI, waist circumference, HDL-cholesterol and insulin concentration mediated the association between adiponectin and MetS-AHA/NHLBI (z-test, standard error, P-value: 2.633, 0.011, 0.008 for BMI; 2.441, 0.011, 0.015 for waist circumference; 1.980, 0.010, 0.048 for HDL-cholesterol; 2.225, 0.009, 0.026 for insulin). However, adiponectin remained significantly associated with MetS. IL-6 was not significantly associated with MetS.

CONCLUSION

MetS components, in particular obesity and lipid indices, as well as serum insulin levels, mediate the association between adiponectin and MetS as defined by both the IDF and AHA/NHLBI criteria.

The effect of microablative fractional CO2 laser on vaginal flora of postmenopausal women

OBJECTIVES

To assess the effect of microablative fractional CO2 laser (MFCO2-Laser) therapy on the vaginal microenvironment of postmenopausal women.

METHODS

Three laser therapies at monthly intervals were applied in postmenopausal women with moderate to severe symptoms of genitourinary syndrome of menopause, pH of vaginal fluid >4.5 and superficial epithelial cells on vaginal smear <5%. Vaginal fluid pH values, fresh wet mount microscopy, Gram stain and aerobic and anaerobic cultures were evaluated at baseline and 1 month after each subsequent therapy. Nugent score and Hay-Ison criteria were used to evaluate vaginal flora.

RESULTS

Fifty-three women (mean age 57.2 ± 5.4 years) participated and completed this study. MFCO2-Laser therapy increased Lactobacillus (p < 0.001) and normal flora (p < 0.001) after the completion of the therapeutic protocol, which decreased vaginal pH from a mean of 5.5 ± 0.8 (initial value) to 4.7 ± 0.5 (p < 0.001). The prevalence of Lactobacillus changed from 30% initially to 79% after the last treatment. Clinical signs and symptoms of bacterial vaginosis, aerobic vaginitis or candidiasis did not appear in any participant.

CONCLUSION

MFCO2-Laser therapy is a promising treatment for improving the vaginal health of postmenopausal women by helping repopulate the vagina with normally existing Lactobacillus species and reconstituting the normal flora to premenopausal status.

The Role of Platelet-Activating Factor in Chronic Inflammation, Immune Activation, and Comorbidities Associated with HIV Infection

With the advent of highly effective antiretroviral therapy, cardiovascular disease has become an important cause of morbidity and mortality among people with treated HIV-1, but the pathogenesis is unclear. Platelet-activating factor is a potent lipid mediator of inflammation that has immunomodulatory effects and a pivotal role in the pathogenesis of inflammatory disorders and cardiovascular disease. Limited scientific evidence suggests that the platelet-activating factor pathway may be a mechanistic link between HIV-1 infection, systemic inflammation, and immune activation that contribute to pathogenesis of chronic HIV-related comorbidities, including cardiovascular disease and HIV-associated neurocognitive disorders. In this review, we examine the mechanisms by which the cross-talk between HIV-1, immune dysregulation, inflammation, and perturbations in the platelet-activating factor pathway may directly affect HIV-1 immunopathogenesis. Understanding the role of platelet-activating factor in HIV-1 infection may pave the way for further studies to explore therapeutic interventions, such as diet, that can modify platelet-activating factor activity and use of platelet-activating factor inhibitors that might improve the prognosis of HIV-1 infected patients.

Hierarchical modelling of blood lipids' profile and 10-year (2002-2012) all cause mortality and incidence of cardiovascular disease: the ATTICA study

Background

The traditional view on the relationship between lipid biomarkers and CVD risk has changed during the last decade. However, it is not clear whether novel lipid biomarkers are able to confer a better predictability of CVD risk, compared to traditional ones.Under this perspective, the aim of the present work was to evaluate the predictive ability of blood lipids’ profile on all cause mortality as well as 10-year incidence of CVD, in a sample of apparently healthy adults of the ATTICA epidemiological study. 

Methods

From May 2001 to December 2002, 1514 men and 1528 women (>18 y) without any clinical evidence of any other chronic disease, at baseline, were enrolled. In 2011–12, the 10-year follow-up was performed in 2583 participants (85 % follow-up participation rate). Incidence of fatal or non-fatal CVD was defined according to WHO-ICD-10 criteria. Baseline serum blood lipids’ profile (Total-C, HDL-, non HDL-, LDL-cholesterol, triglycerides (TG), apolipoprotein (Apo)A1 and B, and lipoprotein–(a) levels were also measured.

Results

The 10-year all-cause mortality rate was 5.7 % for men and 2.0 % for women (p = 0.55). The, 10-year CVD incidence was 19.7 % in men and 11.7 % in women (p < 0.001). Multi-adjusted analysis revealed that TC, non-HDL-C, TG and TG/HDL-C ratio, were independent predictors of all cause mortality (RR per 1 mg/dL or unit (95 % CI): 1.006 (1.000–1.013), 1.006 (1.000–1.013), 1.002 (1.000–1.004), 1.038 (1.001–1.077), respectively). Moreover, TC, HDL-, LDL-, non-HDL-cholesterol, TG, apoA1, TC/HDL-C and TG/HDL-C were independently associated with CVD risk. Among all lipid indices the ratio of apoB/apoA1 demonstrated the best correct reclassification ability, followed by non-HDL-C and TC/HDL-C ratio (continuous Net Reclassification Index 26.1 and 21.2 %, respectively).

Conclusion

Elevated levels of lipid biomarkers are independently associated with all-cause mortality, as well as CVD risk. The ratio of apoB/apoA1, followed by non-HDL-C, demonstrated the best correct classification ability of the developed CVD risk models.

Platelet Activating Factor (PAF) biosynthesis is inhibited by phenolic compounds in U-937 cells under inflammatory conditions

Interleukin 1 beta (IL-1β) induced platelet activating factor (PAF) synthesis in U-937 cells through stimulation of acetyl-CoA:lysoPAF-acetyltransferase (lyso PAF-AT) at 3 h and DTT-independentCDP-choline-1-alkyl-2-acetyl-sn-glycerol cholinophosphotransferase (PAF-CPT) at 0.5 h. The aim of this study was to investigate the effect of tyrosol (T), resveratrol (R) and their acetylated derivatives(AcDs) which exhibit enhanced bioavailability, on PAF synthesis in U-937 after IL-1β stimulation. The specific activity of PAF enzymes and intracellular levels were measured in cell homogenates. T and R concentration capable of inducing 50% inhibition in IL-1β effect on lyso PAF-AT was 48 μΜ ± 11 and 157 μΜ ± 77, for PAF-CPT 246 μΜ ± 61 and 294 μΜ ± 102, respectively. The same order of concentration was also observed on inhibiting PAF levels produced by IL-1β. T was more potent inhibitor than R (p<0.05). AcDs of T retain parent compound inhibitory activity, while in the case of R only two AcDs retain the activity. The observed inhibitory effect by T,R and their AcDs, may partly explain their already reported beneficial role.

In vitro assessment of antioxidant activity of tyrosol, resveratrol and their acetylated derivatives

Consumption of phenolic compounds is associated with beneficial effects in humans even though many of them are poorly absorbed. The aim of this study was to investigate the in vitro antioxidant activity of tyrosol (T), resveratrol (R) and their acetylated derivatives (AcD), as increased lipophilicity has been reported to improve absorption. The chemically synthesized AcDs were evaluated by their ability to scavenge DPPH radicals, inhibit non-enzymatic linoleic acid peroxidation, inhibit human serum oxidation in the presence of copper ions and inhibit lipoxygenase activity. T showed an inhibitory effect only in serum oxidation, where the T-acetylated at aromatic-OH was the most active. The T-acetylated at aliphatic-OH and 3,5-diacetyl-R exhibited the most powerful effect in non-enzymatic linoleic acid peroxidation with IC50 values 2.4 mM ± 0.21 and 0.055 mM ± 0.0018, respectively. In all other tests R was the most potent among all its AcD and T. Increasing lipophilicity by acetylation improves antioxidant activity of phenolic compounds in non-enzymatic lipid peroxidation assays.

Gender-specific distribution of selenium to serum selenoproteins: associations with total selenium levels, age, smoking, body mass index, and physical activity

The epidemiology of selenium (Se) is mainly based on the determination of total serum selenium levels (TSe) which by many aspects is an inadequate marker of Se status. In this study we applied a recently developed LC-ICP-MS method, for the determination of the selenium content of the three main serum selenium-containing proteins, in a subcohort of the ATTICA study. This enables us to investigate whether the selenium distribution to selenoproteins may correlate with demographic (age, gender) and lifestyle variables (smoking, physical activity) that are crucial for the development of chronic diseases. A sub-sample from the ATTICA Study, consisted of 236 males (40 ± 11 years) and 163 females (38 ± 12 years), was selected. The selenium content of glutathione peroxidase (GPx-3), selenoprotein P (SelP) and selenoalbumin (SeAlb) was determined in serum by LC-ICP/MS method. We found that 26% of TSe is found in GPx-3, 61% in SelP and 13% in SeAlb. We have assessed the different ratios of selenoproteins' selenium content (Se-GPX-3/Se-SelP, Se-GPX-3/Se-SeAlb, Se-SelP/Se-SeAlb), showing that people with similar TSe may have different distribution of this selenium to selenoproteins. Total selenium levels and gender are the variables that mostly affect selenium distribution to selenoproteins while age, smoking, physical activity and BMI do not significantly influence selenium distribution. In conclusion, the simultaneous determination of the selenium content of serum selenium-containing selenoproteins is necessary for a thorough estimation of selenium status. The ratio of the Se content between selenoproteins may be proven a novel, valid marker of selenium status.

In vivo effect of two first-line ART regimens on inflammatory mediators in male HIV patients

BACKGROUND

Persistent immune activation and inflammation are lying behind HIV-infection even in the setting of ART mediated viral suppression. The purpose of this study is to define the in vivo effect of two first-line ART regimens on certain inflammatory mediators in male HIV patients.

METHODS

Male, naive, HIV-infected volunteers were assigned either to tenofovir-DF/emtricitabine/efavirenz (Group_T) or abacavir/lamivudine/efavirenz (Group_A). Platelet Activating Factor (PAF) levels and metabolic enzymes together with HIV-implicated cytokines (IL-1beta, IL-6, IL-8, IL-10, IL-12p70, TNFa) and VEGF were determined for a 12-month period. Differences within each group were determined by non-parametric Friedman and Wilcoxon test, while the differences between the groups were checked by ANOVA repeated measures.

RESULTS

Both ART regimens present pronounced effect on inflammatory mediators, resulting in decreased PAF levels and Lipoprotein-associated phospholipase A2 (Lp-PLA2) activity for tenofovir-containing regimen and same as baseline PAF levels with a peak though at the 3rd month as well as elevated Lp-PLA2 activity for abacavir-containing regimen.

CONCLUSIONS

Studies regarding the effect of first-line ART regimens on inflammation may be beneficial in preventing chronic morbidities during HIV-treatment. From this point of view, the present study suggests an anti-inflammatory effect of tenofovir-containing ART, while the temporary increase of PAF levels in abacavir-containing ART may be the link between the reported cardiovascular risk and abacavir administration.

Additional benefit in CVD risk indices derived from the consumption of fortified milk when combined with a lifestyle intervention

OBJECTIVE

The current study aimed to evaluate the effect of fortified milk combined with a lifestyle and counselling programme on several CVD risk factors after a 3-month dietary intervention.

DESIGN

Hypercholesterolaemic adults were randomized to a group supplemented with low-fat milk that was enriched with phytosterols, α-linolenic and linoleic fatty acids, vitamins and antioxidants (enriched milk group, EMG: n 40), a placebo milk group (PMG: n 36) or a control group (CG: n 25). The EMG and PMG consumed respectively 500 ml of enriched milk or placebo milk daily and attended biweekly counselling sessions over a 3-month period.

SETTING

Harokopio University, Athens, Greece.

SUBJECTS

A sample of 101 hypercholesterolemic adults aged 40-60 years.

RESULTS

Regarding lifestyle changes, total and saturated fat intakes decreased significantly in both intervention groups compared with the CG (P < 0·005). Furthermore, total steps were increased (P = 0·029) and BMI was decreased (P = 0·017) significantly in both intervention groups compared with the CG. Regarding biochemical indices, EPA content in erythrocyte membranes increased (P < 0·001) while serum C-reactive protein decreased (P = 0·003) significantly in both intervention groups compared with the CG. Finally, significant increases in plasma folic acid and vitamin B12 levels and a significant decrease in homocysteine levels were observed in the EMG compared with the PMG and CG (all P < 0·001). A favourable change in LDL cholesterol:HDL cholesterol was also observed in the EMG and tended to be significant compared with the PMG and CG (P = 0·066).

CONCLUSIONS

The present study showed that consumption of fortified milk accompanied with lifestyle counselling induces extra benefits in terms of LDL cholesterol:HDL cholesterol and serum homocysteine levels.

Platelet activating factor in heart failure: potential role in disease progression and novel target for therapy

Heart failure (HF) is a complex syndrome with cardiac, renal, neurohormonal and sympathetic nervous system's manifestations, the pathogenesis of which among others is connected to inflammation. PAF has local and systemic effects pertaining to HF progression since it causes a negative inotropic effect, it induces arrhythmias, it induces apoptosis and it is involved in inflammation and atherosclerosis. In the present review the role of PAF in HF will be thoroughly presented along with the relevant data on PAF enzymes and the potential role of PAF metabolic circuit as a novel pharmacological target.

Baseline and 6-Week follow-up levels of PAF and activity of its metabolic enzymes in patients with heart failure and healthy volunteers--a pilot study

This study aimed at evaluating the changes in platelet-activating factor (PAF) and its metabolic enzymes over a 6-week follow-up period in patients with newly diagnosed heart failure ([HF] n = 12) compared with age-, sex-, and BMI-matched apparently healthy volunteers (n = 10). The PAF, its key biosynthetic enzymes (lyso-PAF acetyltransferase [lyso-PAF-AT] and dithiothreitol [DTT]-insensitive CDP choline: 1-alkyl-2-acetyl-sn-glycerol cholinephosphotransferase [PAF-CPT]), and its catabolic isoenzymes (PAF-acetylhydrolase [PAF-AH] and lipoprotein-associated phospholipase A2 [Lp-PLA2]) were measured in serum and leukocytes of participants. At baseline, patients with HF had lower median activities of lyso-PAF-AT (P < .001) and PAF-CPT (P = .07) in parallel with PAF levels (P = .05) and higher activities of PAF-AH (P = .02) and Lp-PLA2 (P < .001) than controls. At follow-up, PAF-CPT and PAF levels marginally increased (P = .1), lyso-PAF-AT (P < .001) remained downregulated, while PAF-AH (P = .004) and Lp-PLA2 (P < .001) remained elevated compared with the controls. Newly diagnosed patients with HF under drug treatment have an affected profile of PAF biosynthetic enzymes and especially lyso-PAF-AT.

Effects of HAART on platelet-activating factor metabolism in naive HIV-infected patients I: study of the tenofovir-DF/emtricitabine/efavirenz HAART regimen

Platelet-activating factor (PAF) is implicated in human immunodeficiency virus (HIV)-related manifestations. Increased PAF synthesis has been recently detected in HIV-infected patients. In this study, we examined in naive HIV-infected patients the in vivo effects of a highly active antiretroviral therapy (HAART) regimen, containing tenofovir-DF/emtricitabine/efavirenz, on PAF metabolism. The specific activities of PAF basic biosynthetic enzymes, PAF-cholinephosphotransferase (PAF-CPT) and lyso-PAF-acetyltransferase (lyso-PAF-AT), but also the ones of PAF-basic catabolic enzymes, PAF acetylhydrolase (PAF-AH) in leukocytes and platelets, and lipoprotein-associated-phospholipase-A(2) (LpPLA(2)) in plasma, were measured in blood samples of eight asymptomatic naive male HIV-infected patients just before and after 1, 3, and 6 months of treatment. CD4 cell counts, viral load, and several biochemical markers were also measured in the same blood samples of these patients. The repeated measures ANOVA and the Pearson r criterion were used to study statistical differences and correlations-partial correlations, while linear mixed models were conducted in order to estimate association(s) between time-dependent changes in these factors. Before treatment, the activities of PAF-CPT in leukocytes and LpPLA(2) in plasma were found to be inversely correlated with CD4 cell counts and positively correlated with the viral load. After 6 months of treatment, the activities of basic PAF-biosynthetic enzymes, PAF-CPT and lyso-PAF-AT, were both reduced in leukocytes. At 6 months, PAF-AH activity was also reduced in these cells, while LpPLA(2) remained stable. The reduction of PAF-CPT occurred even from the first month, while there is a time-dependent correlation between the increase of CD4 and the decrease of both viral load and PAF-CPT of leukocytes during treatment. Apart from its classical antiretroviral activities the tenofovir-DF/emtricitabine/efavirenz regimen also exhibited favorable effects on PAF metabolism and therefore may also display beneficial effects in some HIV-related conditions, such as cardiovascular disease (CVD), in which PAF is implicated.

Effects of highly active antiretroviral therapy on platelet activating factor metabolism in naive HIV-infected patients: ii) study of the abacavir/lamivudine/efavirenz HAART regimen

Human Immunodeficiency Virus (HIV)-infected patients are at increased risk for cardiovascular diseases partly due to chronic inflammation. Some antiretroviral drugs and Highly Active Anti-Retroviral Therapy (HAART) regimens seem to be related and amplify this increased risk, especially the ones containing abacavir. Platelet-Activating-Factor (PAF) is a potent inflammatory mediator that is implicated in both cardiovascular diseases and HIV-related manifestations. Our objective is to study the in vivo effect of the abacavir/lamivudine/efavirenz first-line HAART regimen on PAF metabolism in HIV-infected patients. The specific activities of PAF basic biosynthetic enzymes in leukocytes and platelets, PAF-cholinephosphotransferase (PAF-CPT) and lyso-PAF-acetyltransferase (Lyso-PAF-AT), but also those of PAF-basic catabolic enzymes, PAF acetylhydrolase (PAF-AH) in leukocytes and platelets and Lipoprotein-associated-Phospholipase-A2 (LpPLA2) in plasma, were measured in blood samples of 10 asymptomatic naïve male HIV-infected patients just before and after 1, 3 and 6 months of treatment. CD4 cell counts, viral load and several biochemical markers were also measured in the same blood samples of these patients. The repeated ANOVA measures and the Pearson r criterion were used for studying statistical differences and correlations - partial correlations respectively. Even though viral load was decreased and CD4 cell counts were beneficially increased after treatment with the abacavir/lamivudine/efavirenz regimen, the main enzyme of the remodelling PAF-synthesis that is implicated in pro-atherogenic inflammatory procedures, Lyso-PAF-AT activity, was increased at 3 months of treatment in both leukocytes and platelets, while the main enzyme of PAF-degradation, PAF-AH, was increased as a response only in leukocytes at the 3rd month. Although the abacavir/lamivudine/efavirenz HAART regimen exhibits very efficient antiretroviral activities, on the other hand it induces an in vivo transient increase in the inflammation-related remodeling PAF-biosynthetic pathway. This finding supports the hypothesis of inflammation-mediated increased cardiovascular risk in HIV-infected patients during the first months of abacavir-containing HAART.

Mediterranean wild plants reduce postprandial platelet aggregation in patients with metabolic syndrome

Postprandial platelet hyperactivity and aggregation play a crucial role in the pathogenesis of metabolic syndrome. The purpose of the present study was to evaluate the effect of boiled wild plants consumption on the postprandial platelet aggregation in metabolic syndrome patients. Patients consumed 5 meals in a random order (ie, 4 wild plant meals, namely, Reichardia picroides [RP], Cynara cardunculus, Urospermum picroides [UP], and Chrysanthemum coronarium, and a control meal, which contained no wild plants). Several biochemical indices as well as platelet activating factor (PAF)- and adenosine diphosphate-induced ex vivo platelet aggregation were measured postprandially. Moreover, the ability of plants extract to inhibit rabbit platelet aggregation was tested in vitro. The consumption of RP and UP meals significantly reduced ex vivo adenosine diphosphate-induced postprandial platelet aggregation compared with the control meal. The consumption of UP meals significantly reduced the ex vivo PAF-induced platelet aggregation postprandially. Both UP and RP extracts significantly inhibited PAF-induced rabbit platelet aggregation in vitro. Wild plants consumption reduced postprandial platelet hyperaggregability of metabolic syndrome patients, which may account for their healthy effects.