Peripheral arterial disease has a strong impact on cardiovascular outcome in patients with acute coronary syndromes: from the START Antiplatelet registry.

BACKGROUND: Peripheral arterial disease (PAD) was reported to increase the risk of new cardiovascular events in patients with acute coronary syndromes (ACS). However, most of the evidence comes from randomized clinical trials. We aimed to assess the impact of PAD on cardiovascular outcome and treatment decisions in ACS patients in a current real-life setting. METHODS: START-ANTIPLATELET is a multicenter registry enrolling ACS patient. Baseline clinical characteristics and treatment at discharge were recorded and follow-up was repeated at 6-months and 1-year. PAD was defined as intermittent claudication and/or previous revascularization. RESULTS: Among 1442 patients enrolled, 103 (7.1%) had PAD. PAD patients were older (71.8 ± 10.6vs66.2 ± 12.6 yrs., p < 0.0001), more frequently hypertensive (90.3vs68.6%, p< 0.0001), hypercholesterolemic (66vs52%, p= 0.037), diabetic (51.5vs24%, p= 0.0001), obese (28.2vs19.3%, p= 0.029) and with previous TIA (7.8vs2.8%, p= 0.005) or stroke (11.7vs3.1%, p< 0.0001). Clinical presentation and acute treatment were similar in non-PAD and PAD patients, but the latter were discharged significantly less frequently on dual antiplatelet therapy (DAPT) (68.9vs85%, p= 0.005). After a median follow-up time of 11.1 months, major cardio/cerebrovascular event-free survival [MACCE, including cardiovascular death, MI, TIA and stroke, target-vessel revascularization (TVR) and major arterial ischemic events] was significantly shorter (9.0vs11.2 months, p= 0.02; HR 3.2, 2.4-8.4) in PAD patients and net adverse cardiovascular events (NACE = MACCE plus major hemorrhages) were significantly more frequent (19.1%vs10.5%, p = 0.049). CONCLUSIONS: PAD identifies a subgroup of ACS patients at significantly increased cardiovascular risk, but these patients tend to be undertreated. Patients admitted for ACS should be screened for PAD and optimal medical therapy at discharge should be implemented.

Aging and Adherence to the Mediterranean Diet: Relationship with Cardiometabolic Disorders and Polypharmacy.

OBJECTIVES: To investigate the association between adherence to the Mediterranean Diet (Med-Diet), cardiometabolic disorders and polypharmacy. DESIGN: Cross-sectional study. SETTING: Geriatrics outpatient clinic, Policlinico Umberto I, Sapienza University of Rome. PARTICIPANTS: 508 patients (219 male, 289 female) aged 50 to 89 who were evaluated for cardiovascular and metabolic disorders. METHODS AND MEASUREMENTS: Patients underwent a comprehensive medical assessment including medical history and the use of medications. Adherence to Med-Diet was assessed using the validated Med-Diet 14-item questionnaire; for the analysis, patients were divided in high (≥8) and medium-low (<8) adherence. Polypharmacy was defined as taking ≥5 medications. RESULTS: 476 patients completed the study. Mean age was 70.4 years; 58% female. Median Med-Diet score was 8 (interquartile range, 6-9). Patients with medium-low adherence had higher body mass index (p=0.029) and higher prevalence of arterial hypertension (p<0.001), previous coronary (p=0.002) and cerebrovascular events (p=0.011), diabetes, (p<0.001) and dyslipidemia (p=0.001) compared to those at high adherence. Med-Diet score decreased with the number of cardiometabolic disorders (p<0.001). The prevalence of polypharmacy was 39%. Consumption of olive oil (p=0.005), vegetables, (p<0.001), wine (p=0.017), legumes (p=0.028), fish (p=0.046) and nuts (p=0.045) were all inversely associated with the overall number of medications. In a multivariable regression model, medium-low adherence to Med-Diet was independently associated to polypharmacy (O.R.:1.859; 95% CI 1.142 to 3.025; p=0.013), after adjusting for possible confounding factors. CONCLUSION: Med-Diet was inversely associated with cardiometabolic disorders and with polypharmacy, suggesting that improved Med-Diet adherence might potentially delay the onset of age-related health deterioration and reduce the need of multiple medications.

The Anopheles gambiae ATP-binding cassette transporter family: phylogenetic analysis and tissue localization provide clues on function and role in insecticide resistance.

The role of ATP-binding cassette (ABC) transporters in conferring insecticide resistance has received much attention recently. Here we identify ABC transporters differentially expressed in insecticide-resistant populations of the malaria vector, Anopheles gambiae. Although we found little evidence that the orthologues of the multidrug resistance proteins described in other species are associated with resistance in An. gambiae we did identify a subset of ABC proteins consistently differentially expressed in pyrethroid-resistant populations from across Africa. We present information on the phylogenetic relationship, primary sites of expression and potential role of ABC transporters in mediating the mosquito's response to insecticides. Furthermore we demonstrate that a paralogous group of eight ABCG transporters, clustered on chromosome 3R, are highly enriched in the legs of An. gambiae mosquitoes, consistent with a proposed role for this ABC subfamily in transport of lipids to the outer surface of the cuticle. Finally, antibodies raised against one of the most highly expressed ABC transporters in adult females, ABCG7 (AGAP009850), localized this transporter to the pericardial cells. These data will help prioritize members of this gene family for further localization and functional validation studies to identify the in vivo function of these transporters in the mosquito and determine whether elevated expression of members of this family contribute to insecticide resistance.

Instant loading with intraoral welding technique and PRAMA implants: a new prosthetic approach.

When splinting multiple implants passive fit of the framework should be achieved to avoid excessive force distribution on the implants. Recently, a protocol was suggested for immediate loading of multiple implants by welding a titanium bar to implant abutments directly in the oral cavity so as to create a customized, precise and passive metal-reinforced provisional restoration. The intraoral welding technique subsequently proves to be a successful option in the full-arch immediate restorations of the mandible and maxilla. The aim of this article is to present a case report in which a new prosthetic approach, using trans-mucosal implants, is described. Dental implants are instantly loaded with a provisional prosthesis supported by an intraoral welded titanium framework to obtain a precise passive fit of the immediate loaded prosthesis.

Assessment of risk factors for candidemia in non-neutropenic patients hospitalized in Internal Medicine wards: A multicenter study.

BACKGROUND: An increasing prevalence of candidemia has been reported in Internal Medicine wards (IMWs). The aim of our study was to identify risk factors for candidemia among non-neutropenic patients hospitalized in IMWs. METHODS: A multicenter case-control study was performed in three hospitals in Italy. Patients developing candidemia (cases) were compared to patients without candidemia (controls) matched by age, time of admission and duration of hospitalization. A logistic regression analysis identified risk factors for candidemia, and a new risk score was developed. Validation was performed on an external cohort of patients. RESULTS: Overall, 951 patients (317 cases of candidemia and 634 controls) were included in the derivation cohort, while 270 patients (90 patients with candidemia and 180 controls) constituted the validation cohort. Severe sepsis or septic shock, recent Clostridium difficile infection, diabetes mellitus, total parenteral nutrition, chronic obstructive pulmonary disease, concomitant intravenous glycopeptide therapy, presence of peripherally inserted central catheter, previous antibiotic therapy and immunosuppressive therapy were factors independently associated with candidemia. The new risk score showed good area under the curve (AUC) values in both derivation (AUC 0.973 95% CI 0.809-0.997, p<0.001) and validation cohort (0.867 95% CI 0.710-0.931, p<0.001). A threshold of 3 leads to a sensitivity of 87% and a specificity of 83%. CONCLUSION: Non-neutropenic patients admitted in IMWs have peculiar risk factors for candidemia. A new risk score with a good performance could facilitate the identification of candidates to early antifungal therapy.

Short-term in vivo modifications of platelet NADPH oxidase 2 (NOX2) and prostaglandin F2α in HIV-1 patients on abacavir-based therapies.

OBJECTIVES: The aim of the study was to investigate the in vivo effect of abacavir (ABC) on platelet oxidative stress. METHODS: We performed a randomized pilot study including 39 HIV-1-infected patients, 17 on zidovudine/lamivudine (ZDV/3TC) and 22 on tenofovir/emtricitabine (TDF/FTC). Ten patients on ZDV/3TC and eight patients on TDF/FTC were randomly allocated to switching the nucleoside backbone to ABC/3TC. At baseline and after 6 months, platelet oxidative stress was assessed by platelet NADPH oxidase 2 (NOX2)-derived peptide (sNOX2-dp), a marker of NOX2 activation, and platelet prostaglandin F2α (8-iso-PGF2α ). Platelet activation was measured by soluble CD40L (sCD40L). RESULTS: At baseline, no differences between ZDV/3TC or TDF/FTC recipients were found. After 6 months, patients switching from ZDV/3TC showed a decrease of sNOX2-dp (from 20.9±5.7 to 12.5±3.8 pg/ml, p=0.002) and 8-iso-PGF2α (from 154.3±41.9 to 122.9±28.0 pmol/l, p=0.025). No effects on platelet oxidative stress biomarkers were observed in subjects from TDF/FTC, who showed a significant increase in blood glucose (p=0.043) and total cholesterol (p=0.027). ABC showed no effect on sCD40L levels in both groups. CONCLUSIONS: ABC reduced platelet sNOX2-dp and 8-iso-PGF2α in HIV-1 subjects switching from ZDV/3TC but not in those from TDF/FTC after 6 months. No changes in platelet activation were found in both groups.

Enhanced Soluble Serum CD40L and Serum P-Selectin Levels in Primary Aldosteronism.

Primary aldosteronism (PA) is one of the most frequent forms of secondary hypertension, associated with atherosclerosis and higher risk of cardiovascular events. Platelets play a key role in the atherosclerotic process. The aim of the study was to evaluate the platelet activation by measuring serum levels of soluble CD40L (sCD40L) and P-selectin (sP-selectin) in consecutive PA patients [subgroup: aldosterone-secreting adrenal adenoma (APA) and bilateral adrenal hyperplasia (IHA)], matched with essential hypertensive (EH) patients. The subgroup of APA patients was revaluated 6-months after unilateral adrenalectomy. In all PA group, we measured higher serum levels of both sP-selectin (14.29±9.33 pg/ml) and sCD40L (9.53±4.2 ng/ml) compared to EH patients (9.39±5.3 pg/ml and 3.54±0.94 ng/ml, respectively; p<0.001). After removal of APA, PA patients showed significant reduction of blood pressure (BP) values, plasma aldosterone (PAC) levels and ARR-ratio, associated with a significant reduction of sP-selectin (16.74±8.9 pg/ml vs. 8.1±3.8 pg/ml; p<0.01) and sCD40L (8.6±1 ng/ml vs. 5.24±0.94 ng/ml; p<0.001). In PA patients, we found a significant correlation between sP-selectin and sCD40L with PAC (r=0.52, p<0.01; r=0.50, p<0.01, respectively); this correlation was stronger in APA patients (r=0.54; p<0.01 r=0.63; p<0.01, respectively). Our results showed that PA is related to platelet activation, expressed as higher plasma values of sCD40L and sP-selectin values. Surgical treatment and consequent normalization of aldosterone secretion was associated with significant reduction of sCD40L and sP-selectin values in APA patients.

Extra virgin olive oil use is associated with improved post-prandial blood glucose and LDL cholesterol in healthy subjects.

OBJECTIVES: Extra virgin olive oil (EVOO) is a key component of the Mediterranean diet and seems to account for the protective effect against cardiovascular disease. However, the underlying mechanism is still elusive. DESIGN: We tested the effect of EVOO, added to Mediterranean-type meal, on post-prandial glycemic and lipid profile. SUBJECTS: Post-prandial glycemic and lipid profile were investigated in 25 healthy subjects who were randomly allocated in a cross-over design to a Mediterranean-type meal added with or without 10 g EVOO (first study), or Mediterranean-type meal with EVOO (10 g) or corn oil (10 g; second study). Glycemic profile, which included glucose, insulin, dipeptidyl-peptidase-4 (DPP-4) protein and activity, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), and lipid profile, which included, low-density lipoprotein (LDL) cholesterol (LDL-C), oxidized LDL (ox-LDL), triglycerides and high-density lipoprotein (HDL) cholesterol (HDL-C), were analyzed before and 2 h after the meal. RESULTS: In the first study, 2 h after meal, subjects who assumed a meal with EVOO had significantly lower blood glucose (P<0.001), DPP-4 protein (P<0.001) and activity (P<0.001), LDL-C (P<0.001) and ox-LDL (P<0.001) and higher insulin (P<0.05), GLP-1 (P<0.001) and GIP (P<0.05) compared with those without EVOO. The second study showed that compared with corn oil, EVOO improved both glycemic and lipid profile. Thus, a significantly smaller increase of glucose (P<0.05), DPP4 protein (P<0.001) and activity (P<0.05) and higher increase of insulin (P<0.001) and GLP-1 (P<0.001) were observed. Furthermore, compared with corn oil, EVOO showed a significantly less increase of LDL-C (P<0.05) and ox-LDL (P<0.001). CONCLUSIONS: We report for the first time that EVOO improves post-prandial glucose and LDL-C, an effect that may account for the antiatherosclerotic effect of the Mediterranean diet.

Epicatechin and catechin modulate endothelial activation induced by platelets of patients with peripheral artery disease.

Platelet activation contributes to the alteration of endothelial function, a critical initial step in atherogenesis through the production and release of prooxidant mediators. There is uncertainty about the precise role of polyphenols in interaction between platelets and endothelial cells (ECs). We aimed to investigate whether polyphenols are able to reduce endothelial activation induced by activated platelets. First, we compared platelet activation and flow-mediated dilation (FMD) in 10 healthy subjects (HS) and 10 patients with peripheral artery disease (PAD). Then, we evaluated the effect of epicatechin plus catechin on platelet-HUVEC interaction by measuring soluble cell adhesion molecules (CAMs), NOx production, and eNOS phosphorylation (p-eNOS) in HUVEC. Compared to HS, PAD patients had enhanced platelet activation. Conversely, PAD patients had lower FMD than HS. Supernatant of activated platelets from PAD patients induced an increase of sCAMs release and a decrease of p-eNOS and nitric oxide (NO) bioavailability compared to unstimulated HUVEC. Coincubation of HUVEC, with supernatant of PAD platelets patients, pretreated with a scalar dose of the polyphenols, resulted in a decrease of sCAMs release and in an increase of p-eNOS and NO bioavailability. This study demonstrates that epicatechin plus catechin reduces endothelial activation induced by activated platelets.

Non-alcoholic fatty liver disease, metabolic syndrome and patatin-like phospholipase domain-containing protein3 gene variants.

BACKGROUND & AIMS: Non-alcoholic fatty liver disease was traditionally interpreted as a condition which may progress to liver-related complications. However, the increased mortality is primarily a result of cardiovascular diseases. It has been suggested that fatty liver can be considered as the hepatic consequence of the metabolic syndrome. The aim was to describe the different clinical presentations of non-alcoholic fatty liver disease on the basis of the patatin-like phospholipase domain-containing protein3 (PNPLA3) rs738409 gene variant. METHODS: Fatty liver was defined by ultrasonographic Hamaguchi's criteria in 211 consecutive subjects with non-alcoholic fatty liver disease. The rs738409 polymorphism was determined by TaqMan assays. Metabolic syndrome was defined according to ATPIII modified criteria. RESULTS: Prevalence of PNPLA3-148II, PNPLA3-148IM, and PNPLA3-148MM genotypes was 45.0%, 40.7%, and 14.3% respectively. Prevalence of metabolic syndrome progressively increased with the severity of liver steatosis (from 52.5% to 65.2%, and 82.3% respectively, p<0.01). The PNPLA3-148MM group had significantly lower mean serum triglycerides (p<0.001), Framingham cardiovascular risk score (p<0.01) and lower prevalence of metabolic syndrome (p<0.05) and its components. Age and HOMA-IR were positive independent predictors of metabolic syndrome, while a negative independent association was found between metabolic syndrome and the homozygotes PNPLA3 I148M variant. CONCLUSIONS: We suggest a lower prevalence of MetS and reduced cardiovascular risk in NAFLD patients with PNPLA3MM genotype.

Serum Cytokeratin-18 Is Associated with NOX2-Generated Oxidative Stress in Patients with Nonalcoholic Fatty Liver.

Background & Aims. Hepatocyte apoptosis may play a role in progression of nonalcoholic fatty liver and oxidative stress seems one of the key mechanisms responsible for liver damage. The aim was to determine the association of oxidative stress with cytokeratin-18 M30 fragment levels, a marker of hepatocyte apoptosis. Methods. Steatosis severity was defined according to Hamaguchi's echographic criteria in 209 patients with nonalcoholic fatty liver. Serum cytokeratin-18, urinary 8-iso-prostaglandin F2 α , soluble NOX2-derived peptide, and adiponectin were measured. Results. Serum cytokeratin-18 progressively increased with steatosis severity (from 169.5 (129.3/183.8) to 176 (140/190) and 180 (169.5/192.5) µ IU/mL in mild, moderate, and severe steatosis, respectively; P < 0.01). After stratification by cytokeratin-18 tertiles, a significant progression of body mass index, HOMA-IR, triglycerides, urinary 8-iso-PGF2 α , soluble NOX2-derived peptide, and of the prevalence of diabetes and severe steatosis was found, while HDL-cholesterol and adiponectin progressively decreased. A positive correlation between cytokeratin-18 and body mass index, HOMA-IR, Hamaguchi's score, urinary 8-iso-PGF2 α , and soluble NOX2-derived peptide and a negative correlation between cytokeratin-18 and HDL-cholesterol and adiponectin were found. Body mass index, adiponectin, and soluble NOX2-derived peptide were independent predictors of serum cytokeratin-18 levels (adjusted R (2) = 0.36). Conclusion. We support an association between oxidative stress and severity of liver damage in patients with nonalcoholic fatty liver.

Dark chocolate inhibits platelet isoprostanes via NOX2 down-regulation in smokers.

BACKGROUND: Dark chocolate is reported to decrease platelet activation but the underlying mechanism is still undefined. Dark chocolate is rich in polyphenols that could exert an antiplatelet action via inhibition of oxidative stress. The aim of the present study was to assess if dark chocolate inhibits platelet reactive oxidant species (ROS) formation and platelet activation. METHODS: Twenty healthy subjects (HS) and 20 smokers were randomly allocated to receive 40 g of dark (cocoa > 85%) or milk chocolate (cocoa < 35%) in a cross-over, single-blind study. There was an interval of 7 days between the two phases of the study. At baseline and 2 h after chocolate ingestion, platelet recruitment (PR), platelet ROS, platelet isoprostane 8-ISO-prostaglandin F2α (8-iso-PGF2α), Thromboxane (TxA2) and platelet activation of NOX2, the catalytic sub-unit of NADPH oxidase, and serum epicatechin were measured. RESULTS: Compared with HS, smokers showed enhanced PR, platelet formation of ROS and eicosanoids and NOX2 activation. After dark chocolate, platelet ROS (-48%, P < 0.001), 8-iso-PGF2α (-10%, P < 0.001) and NOX2 activation (-22%, P < 0.001) significantly decreased; dark chocolate did not affect platelet variables in HS. No effect of milk chocolate was detected in both groups. Serum epicatechin increased after dark chocolate in HS (from 0.454 ± 0.3 nm to 118.3 ± 53.7 nm) and smokers (from 0.5 ± 0.28 nm to 120.9 ± 54.2 nm). Platelet incubation with 0.1-10 µm catechin significantly reduced PR, platelet 8-iso-PGF2α and ROS formation and NOX2 activation only in platelets from smokers. CONCLUSIONS: Dark chocolate inhibits platelet function by lowering oxidative stress only in smokers; this effect seems to be dependent on its polyphenolic content.

Effect of L-carnitine on oxidative stress and platelet activation after major surgery.

BACKGROUND: The surgical/anesthesia trauma is associated with an increased production of reactive oxygen species (ROS). This enhanced oxidative stress leads to cell damage resulting in various complications such as sepsis, myocardial injury and increased mortality. The aim of this study was to investigate the role of antioxidant treatment with l-carnitine in oxidative stress and platelet activation in patients undergoing major abdominal surgery. METHODS: Forty patients scheduled for abdominal surgery were randomly allocated to l-carnitine, administered with a rapid infusion (0.05 g/kg) diluted in 250 ml of saline solution, vs. placebo treatment just before the surgical intervention. At baseline and after treatment, oxidative stress was evaluated by detection of circulating levels of soluble NOX2-derived peptide (sNOX2-dp), a marker of NADPH oxidase activation, and by analyzing platelet ROS formation. Platelet activation was studied by dosing sCD40L. RESULTS: We observed an increase of soluble sNOX2-dp, sCD40L and ROS production in the placebo group compared with the baseline after the surgical intervention. Conversely, in the l-carnitine-treated group, sNOX2-dp, sCD40L and ROS production did not significantly differ from the baseline. A linear correlation analysis showed that Δ of ROS correlated with Δ of sNOX2 (R(s) =0.817; P<0.001) and Δ of sCD40L (R(s) =0.780; P<0.001). Multiple linear regression analysis showed that the only independent predictive variable associated with Δ of ROS was Δ of serum NOX2 levels (SE=0.05; standardized coefficient ß=1.075; P<0.001). CONCLUSION: Our findings suggest that l-carnitine could be helpful in modulating oxidative stress and platelet activation during major abdominal surgery-dependent oxidative damage.

Clinical trial: low plasma cholesterol and oxidative stress predict rapid virological response to standard therapy with peginterferon and ribavirin in HCV patients.

BACKGROUND: Rapid virological response (RVR) is the best predictor of sustained response to standard HCV treatment. AIM: To evaluate predictive factors of RVR. METHODS: Sixty-five patients (mean age 52.6 +/- 13.8; 37 genotype-1, and 28 genotypes-2/3) were consecutively treated with pegIFN-alpha 2a or 2b once weekly plus daily ribavirin based on body weight for 24 or 48 weeks, according to genotype. RVR was defined as undetectable HCV-RNA at week 4. RESULTS: Twenty-seven percent of patients achieved RVR in genotypes 1 and 60.7% in genotypes 2/3 (P < 0.01). Rapid responders had higher mean serum baseline total and LDL-cholesterol levels (P < 0.01). RVR was 20.0% in the bottom tertile of total cholesterol and 63.6% in the top tertile (P < 0.01). HCV-RNA levels at week 4 were positively correlated with baseline serum insulin (P < 0.01), HOMA-IR (P < 0.01), body mass index (P < 0.05) and number of components of metabolic syndrome (P < 0.01) and negatively correlated with cholesterol levels (P < 0.05). At multivariate analysis, age, LDL-cholesterol, HCV genotype and serum 8-iso-PGF 2 alpha, a marker of oxidative stress, were independent predictors of RVR. CONCLUSIONS: Our prospective study supports a role of low serum total and LDL-cholesterol and of oxidative stress as positive independent predictive factors of poor RVR in HCV patients.

Myeloperoxidase overexpression in children with hypercholesterolemia.

BACKGROUND: Studies conducted in healthy children showed that biomarkers of oxidative stress decreased with increasing age from 1 to 11 years. No data have been reported concerning the behavior of age-related oxidative stress in hypercholesterolemic children. OBJECTIVE: Aim of this study was to test if children with hypercholesterolemia have prolonged exposure to enhanced oxidative stress and to study the underlying mechanism. METHODS: We performed a cross-sectional study comparing 8-hydroxy-2'deoxyguanosine, oxidized-LDL and myeloperoxidase plasma levels in 95 normocholesterolemic and 95 hypercholesterolemic children. RESULTS: Compared to normocholesterolemic children, those with hypercholesterolemia had higher 8-hydroxy-2'deoxyguanosine, oxidized-LDL and myeloperoxidase plasma levels. A correlation analysis of the overall population showed that total cholesterol was directly correlated with 8-hydroxy-2'deoxyguanosine, oxidized-LDL and myeloperoxidase. Stepwise linear regression showed that only total cholesterol, 8-hydroxy-2'deoxyguanosine and myeloperoxidase levels predicted oxidized-LDL plasma levels. In normocholesterolemic children oxidized-LDL and myeloperoxidase plasma levels significantly decreased from first (1-5 years) to second (6-9 years) quartile of age. In hypercholesterolemic children 8-hydroxy-2'deoxyguanosine, oxidized-LDL and myeloperoxidase plasma levels did not show significant differences among quartiles of age. CONCLUSION: This study shows that an early and persistent oxidative stress is detected in hypercholesterolemic children and that myeloperoxidase up-regulation might play a role.

Effect of coffee drinking on platelets: inhibition of aggregation and phenols incorporation.

Epidemiological studies indicate a J-shaped relationship linking coffee consumption and cardiovascular risk, suggesting that moderate coffee consumption can be beneficial. Platelet aggregation is of critical importance in thrombotic events, and platelets play a major role in the aetiology of several CVD. The aim of this study was to evaluate the effect of coffee drinking on platelet aggregation ex vivo, using caffeine as control. A crossover study was performed on ten healthy subjects. In two different sessions, subjects drank 200 ml coffee, containing 180 mg caffeine, or a capsule of caffeine (180 mg) with 200 ml water. Platelets were separated from plasma at baseline and 30 and 60 min after coffee drinking. Platelet aggregation was induced with three different agonists: collagen, arachidonic acid and ADP. Coffee drinking inhibited collagen (P < 0.05 from baseline at time 30 min) and arachidonic acid (P < 0.05 from baseline at time 60 min) induced platelet aggregation. Caffeine intake did not affect platelet aggregation induced by the three agonists. Coffee consumption induced a significant increase of platelet phenolic acids (likely present as glucuronate and sulphate derivatives), caffeic acid, the principal phenolic acid in coffee, raising from 0.3 (SEM 0.1) to 2.4 (SEM 0.6) ng/mg (P < 0.01). Caffeine was not detectable in platelets. Coffee drinking decreases platelet aggregation, and induces a significant increase in phenolic acid platelet concentration. The antiplatelet effect of coffee is independent from caffeine and could be a result of the interaction of coffee phenolic acids with the intracellular signalling network leading to platelet aggregation.

Oxidative stress-mediated platelet CD40 ligand upregulation in patients with hypercholesterolemia: effect of atorvastatin.

OBJECTIVES: We speculated that in patients with hypercholesterolemia CD40L overexpression could depend on low-density lipoprotein (LDL)-induced enhanced intraplatelet formation of O(2)*(-) and statin could reduce platelet CD40L via interference with platelet O(2)*(-) production. BACKGROUND: CD40L is a protein with inflammatory and thrombotic properties. CD40L is upregulated in platelets from hypercholesterolemic (HC) patients but the underlying mechanism is unclear. METHODS: Collagen-induced platelet CD40L and platelet O(2)*(-) expression were investigated in 40 HC patients and 40 healthy subjects. HC patients were then randomized to either a diet (n = 20) (group A) or atorvastatin 10 mg day (n = 20) (group B); the above variables were measured at baseline and after 3 and 30 days of treatment. O(2)*(-) and CD40L were also measured in vitro in LDL-treated platelets with or without nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor or atorvastatin added. RESULTS: Compared with controls, HC patients showed higher values of platelet CD40L (P < 0.001) and O(2)*(-) (P < 0.001). Platelet CD40L was significantly correlated with O(2)*(-) (P < 0.001). The interventional trial showed no changes in group A and a significant and parallel decrease in platelet CD40L (P < 0.001) and O(2)*(-) (P < 0.001) in group B. In vitro studies demonstrated that LDL-induced platelet CD40L and GP IIb/IIIa (PAC1 binding) activation via the NADPH oxidase pathway. CD40L upregulation was counteracted by atorvastatin in a dose-dependent fashion. CONCLUSIONS: This study suggests that in patients with hypercholesterolemia platelet CD40L is upregulated via NADPH oxidase-dependent O(2)*(-) generation. Atorvastatin downregulated CD40L with an oxidative stress-mediated mechanism likely involving platelet NADPH oxidase, an effect that seemed to be independent of its cholesterol-lowering action.

Oxidative-stress-mediated arterial dysfunction in patients with peripheral arterial disease.

AIMS: To investigate the existence of a relationship among flow-mediated dilation (FMD), nitric oxide (NO), and oxidative stress in patients with peripheral arterial disease (PAD), and to assess if the administration of an antioxidant was able to improve arterial dilatation. METHODS AND RESULTS: We performed a cross-sectional study comparing FMD, 8-Hydroxy-2-deoxy-2-deoxyguanosine (8-OHdG), a marker of oxidative stress, and nitrite/nitrate (NOx) serum levels in a population of 25 PAD patients and 40 controls. In the second part of the study, 21 PAD patients were randomly allocated to a treatment sequence of 7 days of i.v. infusion of placebo or 6 g/day propionyl-L-carnitine (PLC) in a cross-over design. Compared with controls, patients with PAD had enhanced 8-OHdG serum levels (2.4 +/- 1.2 vs. 4.24 +/- 3.11 ng/mL; P < 0.001), reduced NOx (17.02 +/- 6.11 vs. 11.28 +/- 6.02 microM; P < 0.001), and lowered FMD (10.34 +/- 2.14 vs. 6.69 +/- 2.95; P < 0.001). PLC infusion was associated with an increase of FMD [from 6.6 +/- 0.6 to 11.1 +/- 1.2% (mean +/- SE), P = 0.004] and NOx (from 14.5 +/- 1.4 to 17.1 +/- 1.2 microM; +18%, P = 0.012) and a decrease of 8-OHdG (from 3.62 +/- 0.37 to 2.64 +/- 0.32 ng/mL; -27%, P < 0.001). No changes were observed after placebo treatment. CONCLUSION: This study shows that in PAD patients, oxidative stress is implicated in determining reduced FMD.