Endothelial dysfunction markers as a therapeutic target for Sildenafil treatment and effects on metabolic control in type 2 diabetes.

Objective: Endothelial dysfunction (ED) plays a role in diabetic cardiovascular complications. Hyperglycemia increases cytockines involved in vascular inflammation. Inhibition of phosphodiesterase type 5 (PDE5) exerts a relaxation on corpora cavernosa and has cardioprotective properties.

Oxidized low-density lipoproteins impair endothelial function by inhibiting non-genomic action of thyroid hormone-mediated nitric oxide production in human endothelial cells.

Background: Thyroid hormone (TH) plays an important role in the modulation of cardiac function, including contractility and systemic vascular resistance (SVR). 3,5,3'-triiodothyronine (T(3)), the active form of TH, induces the activation of endothelial nitric oxide synthase via PI3K/AKT non-genomic signaling. Hypothyroidism is associated with an increase in SVR and serum low-density lipoproteins (LDL) levels, and accumulation of oxidized LDL (oxLDL) may impair endothelial-dependent vascular relaxation.

Inherited human gp91phox deficiency is associated with impaired isoprostane formation and platelet dysfunction.

Object: Platelet isoprostane 8-ISO-prostaglandin F2α (8-iso-PGF2α), a proaggregating molecule, is believed to derive from nonenzymatic oxidation of arachidonic acid. We hypothesized that NADPH is implicated in isoprostane formation and platelet activation.

Methods And Results: We studied 8-iso-PGF2α in platelets from 8 male patients with hereditary deficiency of gp91(phox), the catalytic subunit of NADPH oxidase, and 8 male controls.

Atorvastatin downregulates monocyte CD36 expression, nuclear NFkappaB and TNFalpha levels in type 2 diabetes.

Aim: Type 2 diabetes increases the risk for cardiovascular disease, and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) reduce cardiovascular events in these patients. The benefits of statin therapy cannot be explained only by the lipid-lowering effect. The aim of this study was to test the effect of atorvastatin therapy on CD36 scavenger receptor expression, nuclear factor-kappaB (NFkappaB) levels and markers of inflammation (C-reactive protein, CRP, Tumor Necrosis Factor-alpha, TNF-alpha) in circulating monocytes from diabetic patients.

GD3 nuclear localization after apoptosis induction in HUT-78 cells.

Glycosphingolipids are essential components of plasma membrane and act as antigens, mediators of cell adhesion, and modulators of signal transduction. Following activation of the Fas receptor, gangliosides are recuited in various intracellular compartments. We have evaluated whether the pro-apoptotic anti-CD95 antibody induces a nuclear localization of GD3 in HUT-78 cells.

Inhibition of Poly(ADP-ribose)polymerase impairs Epstein Barr Virus lytic cycle progression.

Background: Poly(ADP-ribosylation) is a post-translational modification of nuclear proteins involved in several cellular events as well as in processes that characterize the infective cycle of some viruses. In the present study, we investigated the role of poly(ADP-ribosylation) on Epstein-Barr Virus (EBV) lytic cycle activation.

Results: Inhibition of PARP-1 by 3-aminobenzamide (3-ABA) during EBV induction, diminished cell damage and apoptosis in the non-productive Raji cell line while markedly reducing the release of viral particles in the productive Jijoye cells.

Antioxidant treatment associated with sildenafil reduces monocyte activation and markers of endothelial damage in patients with diabetic erectile dysfunction: a double-blind, placebo-controlled study.

Objective: To investigate the synergic effect of propionyl L-carnitine (PLC) plus sildenafil in reducing monocyte oxidative activity and endothelial dysfunction markers in diabetic patients with erectile dysfunction (ED).

Methods: Thirty-two type 2 diabetic patients with ED (according to the International Index of Erectile Function-5 [IIEF-5]) were randomized to receive PLC (2 g/d) alone (n=8) or combined with sildenafil (50 mg/d twice weekly) (n=8), sildenafil alone (50 mg/d twice weekly) (n=8), or placebo (n=8) in a double-blind, fixed-dose study. Monocyte oxidative activity (stimulation index [SI]), intercellular adhesion molecule-1 [ICAM-1], P-selectin, advanced glycation end product (AGE) levels, Doppler sonography (recording peak systolic velocity [PSV]; end diastolic velocity [EDV]; systolic wave time [SWT]; resistive index [RI]), and IIEF score were evaluated before and after 12 wk of treatment; IIEF-5 was evaluated again 4 wk posttreatment.

Circulating monocyte oxidative activity is increased in patients with type 2 diabetes and erectile dysfunction.

Purpose: We investigated the relationship between oxidative stress and diabetic erectile dysfunction.

Materials And Methods: A total of 23 patients with a mean +/- SD age of 56.7 +/- 5.

Phenotypic and functional characterization of lymphocytes in autoimmune thyroiditis and in papillary carcinoma.

Background: Infiltrates of lymphocytes are found in both autoimmune thyroid disease and papillary cancer and are responsible for thyroid destruction in autoimmune disease. Their role in neoplastic transformation is not yet clear.

Materials And Methods: Phenotypic studies and the capacity to undergo apoptosis were assessed on peripheral and gland infiltrating lymphocytes from patients with autoimmune thyroiditis and papillary carcinoma.

Tumor necrosis factor-alpha as trigger of platelet activation in patients with heart failure.

The clinical history of patients with heart failure (HF) is complicated by arterial thromboembolism. Platelet activation is reported in this population, but the underlying mechanism has not been clarified. Forty-two patients with HF scored according to New York Heart Association (NYHA) classification had higher levels of collagen-induced platelet aggregation, platelet tumor necrosis factor-alpha (TNF-alpha) receptor expression, and serum thromboxane B2 and higher circulating levels of TNF-alpha than 20 healthy subjects.

Vitamin C inhibits platelet expression of CD40 ligand.

Upon stimulation with agonists, platelets express CD40 ligand (CD40L), a transmembrane protein implicated in the initiation and progression of atherosclerotic disease. We have recently discovered that oxidative stress plays a major role in platelet CD40L expression. In this study, we sought to determine whether vitamin C, a known antioxidant, is able to influence platelet CD40L expression.

Short-term treatment with atorvastatin reduces platelet CD40 ligand and thrombin generation in hypercholesterolemic patients.

Background: Soluble CD40L (sCD40L), a substance that maximally reflects in vivo platelet activation, is increased in patients with hypercholesterolemia. We investigated the relation between sCD40L and platelet CD4OL in hypercholesterolemic patients before and after a short-term treatment with atorvastatin.

Methods And Results: Collagen-induced platelet CD40L and plasma levels of sCD40L and prothrombin fragment F1+2, a marker of thrombin generation, were investigated in 30 hypercholesterolemic patients and 20 healthy subjects.

Enhanced platelet release of superoxide anion in systemic hypertension: role of AT1 receptors.

Background: Enhanced oxidative stress has been observed in hypertension, but the underlying mechanism has not been fully clarified.

Objective: To study the relationship between oxygen free radicals and hypertension, using platelets as a tool to measure the cellular production of superoxide anion (O2).

Design: Forty patients with hypertension were allocated randomly to groups to receive either irbesartan, an inhibitor of angiotensin II type 1 (AT1) receptors (n = 20), or a diuretic (hydrochlorothiazide) (n = 20).

Triacsin C inhibits the formation of 1H NMR-visible mobile lipids and lipid bodies in HuT 78 apoptotic cells.

Nuclear magnetic resonance-visible mobile lipids (ML) have been reported to accumulate during cell apoptosis in vitro and in vivo. The biogenesis, biochemical nature and structure of these lipids are still under debate. In this study, a human lymphoblastoid cell line, HuT 78, was induced to apoptosis by exposure to anti-Fas monoclonal antibodies (alpha-Fas mAb) followed by incubation for different time intervals (1-24 h, hypodiploid cell fraction, H, varying from 1% to over 60%) either in the presence or in the absence of 5.

Red and white wine differently affect collagen-induced platelet aggregation.

Moderate consumption of wine is associated with reduced cardiovascular events, but the mechanism is not fully elucidated. Aim of the study was to seek if consumption of red or white wine, that are known to have different amount of polyphenols, differently influenced platelet aggregation. 20 healthy subjects were randomly allocated to consume for two weeks 300 ml of red or white wine; both wines had the same concentration of alcohol.

Enhanced TNF alpha and oxidative stress in patients with heart failure: effect of TNF alpha on platelet O2- production.

Experimental studies have suggested that TNF alpha, a pro-inflammatory cytokine, may contribute to the deterioration of cardiovascular function through various mechanisms, including the generation of reactive oxygen species. It has not yet been demonstrated whether TNF alpha has prooxidant activity in patients with heart failure, and what the mechanism eventually resulting in this effect are. We analyzed 42 patients (38 men and 4 women, aged 26 to 74 years) with heart failure, secondary to idiopathic dilated cardiomyopathy (n=21), coronary artery disease (n=15), and valve disease (n=6), and 20 controls (18 men and 2 women, aged 49 to 67 years).

Immunomodulation during sublingual therapy in allergic children.

The clinical efficacy of sublingual immunotherapy (SLIT) has been demonstrated, but its mechanism of action is still controversial. The most recent experimental observations suggest that a critical role in the modulation of immune response is sustained by Th2 cytokines, such as interleukin-4 (IL-4), IL-5 and IL-13, by co-stimulatory molecules, such as CD40 on B cells, and by hormones and neuropeptides. To better understand whether SLIT affects immune responses we used a double-blind placebo-controlled design.

Two-step formation of 1H NMR visible mobile lipids during apoptosis of paclitaxel-treated K562 cells.

Despite increasing evidence on the formation of 1H NMR-detectable mobile lipid (ML) domains in cells induced to programmed cell death by continuous exposure to anticancer drugs, the time course of ML generation during the apoptotic cascade has not yet been fully elucidated. The present study shows that ML formation occurs at two different stages of apoptosis induced in human erythroleukemia K562 cells by a brief (3 hr) exposure to paclitaxel (Taxol), an antitumour drug with a stabilising effect on microtubules, or to paclitaxel plus tyrphostin AG957, a selective inhibitor of the p210(BCR-ABL) tyrosine kinase activity. A first wave of ML generation was in fact detected in paclitaxel-treated cells at the onset of the effector phase (8-24hr after exposure to the drug), plateaued at 24-48 hr and was eventually followed by further ML accumulation during the degradative phase (48-72 hr).

SH2-containing inositol phosphatase (SHIP-1) transiently translocates to raft domains and modulates CD16-mediated cytotoxicity in human NK cells.

Membrane recruitment of the SH2-containing 5' inositol phosphatase 1 (SHIP-1) is responsible for the inhibitory signals that modulate phosphatidylinositol 3-kinase (PI3K)-dependent signaling pathways. Here we have investigated the molecular mechanisms underlying SHIP-1 activation and its role in CD16-mediated cytotoxicity. We initially demonstrated that a substantial fraction of SHIP-1-mediated 5' inositol phosphatase activity associates with CD16 zeta chain after receptor cross-linking.

Increased superoxide anion production by platelets in hypercholesterolemic patients.

Objectives: The purpose of this study was to investigate the relationship between hypercholesterolemia and superoxide anion production.

Background: Experimental studies demonstrated that hypercholesterolemia is associated with enhanced cellular superoxide anion (O2-) production. Aim of the study was to assess whether the same phenomenon occurs in humans.

Beta-amyloid-induced synthesis of the ganglioside GD3 is a requisite for cell cycle reactivation and apoptosis in neurons.

We have shown that cortical neurons challenged with toxic concentrations of beta-amyloid peptide (betaAP) enter the S phase of the cell cycle before apoptotic death. Searching for a signaling molecule that lies at the border between cell proliferation and apoptotic death, we focused on the disialoganglioside GD3. Exposure of rat cultured cortical neurons to 25 microm betaAP(25-35) induced a substantial increase in the intracellular levels of GD3 after 4 hr, a time that precedes neuronal entry into S phase.

Vitamin E potentiates the antiplatelet activity of aspirin in collagen-stimulated platelets.

Background And Objectives: The combination of vitamin E with aspirin is becoming an attractive therapeutic approach to prevent thrombotic vascular accidents. In this study we investigated the capacity of vitamin E (50 and 100 M) to enhance the antiplatelet effect of aspirin.

Design And Methods: The dose-response curves of platelet aggregation, dense body secretion, phospholipase C activation and calcium mobilization were measured in aspirin-treated platelets with and without added vitamin E (50 and 100 M).

Association of GM3 with Zap-70 induced by T cell activation in plasma membrane microdomains: GM3 as a marker of microdomains in human lymphocytes.

Recent evidence demonstrated that T cell activation leads to the redistribution of membrane and intracellular kinase-rich raft microdomains at the site of TCR engagement. In this investigation we demonstrated by high performance thin layer chromatography, gas chromatographic, and mass spectrometric analyses that GM3 is the main ganglioside constituent of these microdomains in human lymphocytes. Then we analyzed GM3 distribution and its interaction with the phosphorylation protein Zap-70.