Oxidative status in different settings and with different methodological approaches compared by Receiver Operating Characteristic curve analysis.

Objectives: To test the performance of different analytical approaches in highlighting the occurrence of deregulated redox status in various physio-pathological situations.

Design And Methods: 35 light and 61 heavy smokers, 19 chronic renal failure, 59 kidney transplanted patients, and 87 healthy controls were retrospectively considered for the study. Serum oxidative stress and antioxidant status, assessed by spectrophotometric Reactive Oxygen Metabolites (d-ROMs) and Total Antioxidant Capacity (TAC) tests, respectively, were compared with plasma free (F-MDA) and total (T-MDA) malondialdehyde, both quantified by isotope-dilution-gas chromatography-mass spectrometry (ID-GC-MS).

An encapsulated juice powder concentrate improves markers of pulmonary function and cardiovascular risk factors in heavy smokers.

Objective: Cigarette smoking is associated with reduced pulmonary function and increased risk factors for cardiovascular disease. This randomized placebo-controlled double-blind study evaluated the effects of two different combinations of mixed fruit and vegetable juice powder concentrate (Juice Plus+, NSA, Collierville, TN) on heavy smokers.

Methods: At baseline (T 0) and after 3 months' supplementation (T 1), pulmonary function parameters and cardiovascular risk factors-that is, plasma total homocysteine (tHcy) with related B vitamins and cysteine (tCys) concentrations-were assessed in 75 apparently healthy smokers (aged 49.

Plasma total cysteine and cardiovascular risk burden: action and interaction.

We hypothesized that redox analysis could provide sensitive markers of the oxidative pathway associated to the presence of an increasing number of cardiovascular risk factors (RFs), independently of type. We classified 304 subjects without cardiovascular disease into 4 groups according to the total number of RFs (smoking, hypertension, hypercholesterolaemia, hyperhomocysteinaemia, diabetes, obesity, and their combination). Oxidative stress was evaluated by measuring plasma total and reduced homocysteine, cysteine (Cys), glutathione, cysteinylglycine, blood reduced glutathione, and malondialdehyde.

Simultaneous free and glycosylated pyridinium crosslink determination in urine: validation of an HPLC-fluorescence method using a deoxypyridinoline homologue as internal standard.

Pyridinoline (Pyr), deoxypyridinoline (D-Pyr), galactosyl-pyridinoline (Gal-Pyr) and glucosyl-galactosyl pyridinoline (GluGal-Pyr) are enzymatic mature pyridinium crosslinks. Generally, only total Pyr and D-Pyr urinary amounts (free+bound forms) are evaluated by HPLC as indices of bone resorption. This report describes the validation of an HPLC-fluorescence method for the simultaneous evaluation of free Pyr and D-Pyr, together with GluGal-Pyr and Gal-Pyr, in urine of healthy women (n=20, aged 27-41) and girls (n=20, aged 5-10).

Effects of encapsulated fruit and vegetable juice powder concentrates on oxidative status in heavy smokers.

Objective: Long-term cigarette smoking has negative effects on oxidative status, promoting low-density lipoprotein (LDL) oxidation and formation of lipid peroxides. We evaluated the effects of 2 different encapsulated formulas, consisting primarily of mixed juice powder concentrate, on oxidative status compared with placebo.

Methods: This randomized, double-blind, placebo-controlled study was performed on 101 apparently healthy heavy smokers (>20 cigarettes/d, duration >10 years; median age 47 years, range 41-57 years; 54 M) before and after 3 months' supplementation.

Proteomics reveals novel oxidative and glycolytic mechanisms in type 1 diabetic patients' skin which are normalized by kidney-pancreas transplantation.

Background: In type 1 diabetes (T1D) vascular complications such as accelerated atherosclerosis and diffused macro-/microangiopathy are linked to chronic hyperglycemia with a mechanism that is not yet well understood. End-stage renal disease (ESRD) worsens most diabetic complications, particularly, the risk of morbidity and mortality from cardiovascular disease is increased several fold.

Methods And Findings: We evaluated protein regulation and expression in skin biopsies obtained from T1D patients with and without ESRD, to identify pathways of persistent cellular changes linked to diabetic vascular disease.

Dimethylarginines in complicated type 1 diabetes: roles of insulin, glucose, and oxidative stress.

To investigate the roles of insulin, glucose, and oxidative stress on plasma asymmetric and symmetric dimethylarginine (ADMA, SDMA) levels in complicated diabetes, we studied patients with type 1 diabetes (T1D; n = 20), T1D + end-stage renal disease under hemodialysis (T1D + ESRD; n = 12), T1D + ESRD who received kidney transplant (KD; n = 16), and T1D + ESRD who received kidney-pancreas transplant (KP; n = 20) and healthy controls (n = 50). Levels of ADMA, SDMA, and free and total malondialdehyde (MDA) were increased in all patients, with the highest rises for SDMA and free MDA in T1D+ESRD. In KP, the normalized glycemia contributes to the recovery of ADMA, SDMA, and MDA levels toward normal values.

Effects of alpha-lipoic acid administration on plasma glucose levels, total malondialdehyde values and withdrawal signs in rats treated with morphine or morphine plus naloxone.

Morphine (CAS 57-27-2) administration or its removal induces alterations in glucose levels and oxidative status or behaviour signs, which may be hypothetically closely related; if this is correct, controlling glucose changes may lead to modifications in peroxide levels and in behaviour profile. It therefore seems important to find a drug able to control alterations of glucose metabolism, peroxide generation and behaviour symptoms in morphine or morphine withdrawal animals. This paper describes the effects of morphine or morphine plus naloxone (CAS 51481-60-8) on the plasma levels of glucose, malondialdehyde (MDA) (CAS 100683-54-3) and behavioural signs in rats treated or not with alpha-lipoic acid (CAS 1077-28-7), known to interfere with glucose and peroxide levels.

Morphine or its withdrawal affects plasma malondialdehyde, vitamin E levels and absence or presence of abstinence signs in rats.

Objectives: Various experimental observations show that morphine treatment generates reactive oxygen species, and that its discontinuation leads to signs of withdrawal. We therefore investigated plasma malondialdehyde and vitamin E levels under both conditions to verify the occurrence of any alterations in oxidative metabolism, and whether these are associated with behavioural changes.

Methods: We investigated the effects of morphine or morphine plus naloxone on plasma malondialdehyde, vitamin E levels and withdrawal signs such as jumping, wet dog shakes and faecal excretion in rats.

Free and total plasma malondialdehyde in chronic renal insufficiency and in dialysis patients.

Background: Available data about oxidative status in patients with end-stage renal disease (ESRD) or on dialysis are contradictory. The present cross-sectional study aimed to investigate the role of renal insufficiency and dialysis on lipid peroxidation. To separate the effects of uraemia from dialysis-induced stress, we enrolled 26 patients with renal insufficiency on conservative treatment (ESRD), 23 on peritoneal dialysis (PD), 30 on haemodialysis (HD) and 30 controls.

Plasma malondialdehyde levels and opiate withdrawal signs observed in rats treated with morphine plus naloxone: effects of alpha-lipoic acid administration.

A number of experimental studies have found that reactive oxygen species are involved during morphine treatment or withdrawal. The aims of this study were to analyse whether morphine administration and/or removal are related to peroxide generation and/or signs of withdrawal in rats, and whether the changes in antioxidant status induced by the administration of an antioxidant may modify peroxide levels and behavioural signs. We injected morphine or morphine and naloxone into rats and evaluated the plasma levels of peroxide malondialdehyde (MDA) and the appearance of withdrawal signs.

Anesthetic propofol enhances plasma gamma-tocopherol levels in patients undergoing cardiac surgery.

Background: Propofol (2,6-diisopropylphenol) is an anesthetic drug with antioxidant and antiinflammatory properties, documented both in vitro and in experimental models of ischemia-reperfusion injury and septic shock. These properties have been related to the similarity of its chemical structure to that of endogenous tocopherols, which are phenol-containing radical scavengers. This study evaluated the effects of propofol on alpha- and gamma-tocopherol (alpha- and gamma-T) levels and on selected markers of oxidant-antioxidant and inflammatory status in patients undergoing cardiac surgery.

Plasma glutathione levels are independently associated with gamma-glutamyltransferase activity in subjects with cardiovascular risk factors.

To investigate whether GGT (gamma-glutamyltransferase) is associated to specific redox patterns. GGT, total and reduced aminothiols and malondialdehyde, were measured in 150 subjects (83 males, 48 (39-56) years), with none, one or more risk factors. By univariable analysis GGT was positively associated with age (p =0.

Aminothiol redox alterations in patients with chronic heart failure of ischaemic or non-ischaemic origin.

Objective: Oxidative stress plays a role in the progression of chronic heart failure (CHF), but whether and how ischaemic heart disease (IHD) or non-IHD aetiology may account for differential redox alterations is currently unclear. We assessed the relation between thiol redox state and lipid peroxidation, as a marker of oxidative stress, in patients with CHF of ischaemic or non-ischaemic origin.

Methods: Blood reduced glutathione, plasma total and reduced cysteine, cysteinylglycine, homocysteine, glutathione, plasma alpha-tocopherol, ascorbic acid, and free malondialdehyde were assessed in 43 CHF heart transplant candidates (24 IHD and 19 non-IHD) and 30 controls matched for age, gender and number of atherosclerotic risk factors.

Glutamate-cysteine ligase polymorphism, hypertension, and male sex are associated with cardiovascular events. Biochemical and genetic characterization of Italian subpopulation.

Background: Glutathione (GSH) is an important intravascular scavenger that protects endothelial cells from atherosclerosis. However, it is still unknown whether cardiovascular (CV) events are associated with metabolic and genetic factors, linked to GSH synthesis in an Italian subpopulation, and if a glutamate-cysteine ligase polymorphism within the catalytic subunit (GCLC) could affect blood and plasma GSH concentrations.

Methods: One hundred subjects, with or without CV risk factors, were enrolled to evaluate plasma and erythrocyte redox status (GSH, homocysteine, cysteine, cysteinylglycine), antioxidant vitamins (alpha-tocopherol and ascorbate), malondialdehyde, a lipid peroxidation product, and the presence of the GCLC-129 C/T polymorphism; an experimental hyperhomocysteinemia after methionine-induced stimulation of transsulfuration pathway was performed in 91% of enrolled subjects.

Pre-operative redox state affects 1-month survival in patients with advanced heart failure undergoing left ventricular assist device implantation.

Background: Left ventricular assist device (LVAD) implantation has proven effective as a bridge to transplantation in end-stage heart failure patients (ESHFPs), although survival during device support is critical. Oxidative stress has been implicated in the development of heart failure, but the influence of redox state on in-hospital post-LVAD outcome has not been clarified.

Methods And Results: In this report we describe the oxidant/anti-oxidant profiles of 15 ESHFPs before LVAD placement, 5 of whom did not survive to 1 month, and in 30 subjects without cardiac disease, representing the control group.

Low plasma glutathione levels after reperfused acute myocardial infarction are associated with late cardiac events.

Objective: To clarify whether an altered redox state persists in the subacute phase of myocardial infarction and if specific redox patterns are associated with later cardiac events.

Methods: Ninety-seven patients [80 men, median 63 (interquartile range, 53, 69) years] with a first acute myocardial infarction, with (53%) or without ST segment elevation, treated with successful percutaneous interventions, were tested at 5-6 days after admission for plasma alpha-tocopherol, ascorbic acid, total and reduced homocysteine, cysteine, glutathione, cysteinylglycine and blood-reduced glutathione, all assessed by high-pressure liquid chromatography. Free malondialdehyde was evaluated by gas chromatography.

Methionine challenge paradoxically induces a greater activation of the antioxidant defence in subjects with hyper- vs. normohomocysteinemia.

To determine whether hyperhomocysteinemia induced post-methionine loading (PML) is associated with different response in the aminothiol redox state and oxidative stress vs. normohomocysteinemia, we assessed PML plasma thiols, vitamins, free malondialdehyde (MDA), and blood reduced glutathione (GSH) in 120 consecutive subjects (50 [35-56] years, 83 males), divided into two groups according to PML plasma total Hcy < 35 microM (Group 1, n = 65) or > or = 35 microM (Group 2, n = 55). In the group as a whole, plasma reduced cysteine and cysteinylglycine, blood reduced GSH (all p for time = 0.

Blood glutathione as independent marker of lipid peroxidation in heart failure.

Background: Aminothiols have a critical function as intracellular redox buffers and constitute furthermore an important extracellular redox system. Lipid peroxidation is increased in chronic heart failure (CHF), but the contribution of each thiol to oxidative stress in this syndrome has not been evaluated.

Aim: To assess the correlation between blood and plasma concentrations of aminothiols and lipid peroxidation as marker of oxidative stress in CHF patients.

Effect of homocysteine lowering by 5-methyltetrahydrofolate on redox status in hyperhomocysteinemia.

The endothelial dysfunction induced by hyperhomocysteinemia can be reversed by 5-methyltetrahydrofolate (5-MTHF) via homocysteine (Hcy) lowering. An additive antioxidant action of 5-MTHF has been suggested to ameliorate endothelial dysfunction through increased nitric oxide production and superoxide radical scavenging, independent of Hcy lowering. The aim of the study was to assess whether 5-MTHF affects the redox state in hyperhomocysteinemia.

Increased free malondialdehyde concentrations in smokers normalise with a mixed fruit and vegetable juice concentrate: a pilot study.

Background: Cigarette smoking, a cardiovascular risk factor leading to oxygen free radical formation, is involved in the development of serious pathological conditions. On the other hand, a healthy diet and adequate supplementation can help prevent many diseases. The aim of our study was to evaluate in healthy light smokers the effects of supplementation with mixed fruit and vegetable juice powder concentrate on homocysteine metabolism and oxidative status.

Isoprostanes and oxidative stress in off-pump and on-pump coronary bypass surgery.

Background: Conventional on-pump coronary artery bypass grafting (CABG) is associated with a systemic inflammatory response and by an increased production of reactive oxygen species, whereas off-pump coronary artery bypass grafting (OPCAB) is thought to be accompanied by less oxidative stress. Urinary isoprostane iPF2alpha-III is a new marker reflecting oxidative stress; it has emerged as the most reliable marker of oxidative stress status in vivo. This study was designed to ascertain whether OPCAB compared with CABG represents a surgical strategy that avoids oxidative stress.

Creatinine determination in serum by capillary electrophoresis.

Creatinine in human serum was separated in a fused-silica capillary with H3PO4 (75 mmol/L, pH 2.5) as BGE, followed by UV detection at 200 nm. Serum with methylimidazole added as internal standard was deproteinized with acetonitrile and the supernatant, after dilution with water was injected at pressure mode.