Oral but not intravenous glucose acutely decreases circulating interleukin-6 concentrations in overweight individuals.

Background: Plasma interleukin-6 (IL-6) concentrations decrease acutely 1 h after ingestion of a glucose load or mixed meals and this may be mediated by an anti-inflammatory effect of insulin. The aim of the present study was to compare the effect of higher versus lower insulin levels on plasma IL-6 concentrations following oral compared with intravenous glucose administration in overweight/obese subjects.

Methods And Findings: Fifteen subjects (12 women and 3 men) with BMI >28 kg/m(2) were given an oral glucose load (75 g) followed a week later by an intravenous infusion of glucose aimed at matching plasma glucose concentrations during the oral glucose load.

Postprandial response of plasma IL-6 to isoenergetic meals rich in casein or potato singly and combined in obese women.

Milk consumption decreases inflammatory stress in overweight and obese subjects. Casein is the major protein in milk and enhances the secretion of insulin that has anti-inflammatory activity. The aim of the present study was to compare the acute effect of meals rich in casein and carbohydrate and a combination of both nutrients on postprandial plasma concentrations of IL-6, a marker of inflammation, in obese women.

Paraoxonase 1 activity in chylomicrons and VLDL: the effect of type 2 diabetes and meals rich in saturated fat and oleic acid.

Paraoxonase 1 (PON 1) has antioxidant and cardioprotective properties and is abnormally low in type 2 diabetic serum. This study aimed to determine the effect of type 2 diabetes and meals rich in saturated fat and oleic acid on PON1 activity in chylomicrons and very low density lipoproteins (VLDL). PON1 arylesterase activity was measured in chylomicrons and VLDL that were isolated in serum from 20 patients with type 2 diabetes and 20 age- and gender-matched, overweight controls 3 h after meals rich in cream or olive oil in a randomized, cross-over study.

Ingestion of native and thermally oxidized polyunsaturated fats acutely increases circulating numbers of endothelial microparticles.

Circulating numbers of endothelial microparticles (EMP) are an index of endothelial injury and dysfunction; and microparticles positive to CD31 antibody increase acutely after cooked, fatty fast-food meals that are rich in saturated fatty acids (SAFA) and lipid oxidation products. The aim of this study was to determine the acute effect of meals rich in SAFA and native and thermally oxidized polyunsaturated vegetable oil on circulating numbers of EMP positive to CD144 antibody, a more specific marker of EMP. Twenty-two apparently healthy subjects received isocaloric meals rich in cream (CR), unheated sunflower oil, or heated sunflower oil in a randomized crossover study design.

Postprandial cytokine concentrations and meal composition in obese and lean women.

The aim of this study was to compare the acute effect of (i) meals rich in saturated fat, oleic acid, and alpha-linolenic acid and (ii) meals rich in starch and fiber on markers of inflammation and oxidative stress in obese and lean women. In a crossover study, 15 abdominally obese women (age, 54 +/- 9 years; BMI, 37.3 +/- 5.

The effect of glucose ingestion on inflammation and oxidative stress in obese individuals.

Ingestion of 75 g glucose during an oral glucose tolerance test (OGTT) increases systemic inflammation and oxidative stress in healthy subjects and patients with type 2 diabetes mellitus, but the effect in overweight/obese nondiabetic individuals is uncertain. The aim of the present study was to determine the effect of an OGTT on plasma concentrations of inflammatory cytokines and peroxides in 33 subjects with body mass index >27 kg/m(2). After an overnight fast, blood samples were taken from participants immediately before and at 30, 60, 90, and 120 minutes after ingestion of 75 g glucose.

The effect of rosiglitazone on oxidative stress and insulin resistance in overweight individuals.

Objective: The purpose of this study was to examine the chronic effect of rosiglitazone on oxidative stress, inflammatory markers and hepatic risk factors for type 2 diabetes in overweight individuals. In addition we examined the effect of rosiglitazone on post-glucose challenge levels of glucose and insulin.

Research Design And Methods: Forty overweight individuals (BMI>27kg/m(2)) were randomized in a double blind fashion to receive 6 months treatment with either rosiglitazone 4mg/day or placebo.

Plasma protein lipofuscin-like fluorophores in men with coronary artery disease treated with statins.

Background: Lipid oxidation products react with protein to produce lipofuscin-like fluorophores (P-LLF) and modified apolipoprotein B that is an important element of the atherogenic properties of oxidized low-density lipoprotein (oxLDL). The aim of this study was to compare plasma concentrations of P-LLF between men with coronary artery disease (CAD) treated with statin drugs and healthy controls and to identify determinants of P-LLF.

Methods: Plasma markers of protein modification including P-LLF and oxidized low-density lipoprotein-4E6 (oxLDL-4E6), low-density lipoprotein-conjugated dienes (LDL-CD), lipid peroxides, apolipoprotein B, and serum albumin were measured in 24 men with CAD who were receiving statin therapy and 20 healthy men in the same age range.

Effect of dietary cholesterol and fat on cell cholesterol transfer to postprandial plasma in hyperlipidemic men.

Postprandial chylomicrons are potent ultimate acceptors of cell membrane cholesterol and are believed to accelerate reverse cholesterol transport (RCT). We compared the effects of meals rich in polyunsaturated fat (PUFA) and either high (605 mg) or low (151 mg) in cholesterol and a meal rich in dairy fat (DF) in the form of cream on net in vitro transport of red blood cell (RBC) membrane cholesterol to 4 and 6 h postprandial plasma in eight normotriglyceridemic (NTG-H) and eight hypertriglyceridemic (HTG-H) men with mild to moderate hypercholesterolemia. In HTG-H men, cell cholesterol accumulation in 6-h postprandial plasma was significantly (P = 0.

Vitamin E supplementation and plasma 8-isoprostane and adiponectin in overweight subjects.

Objective: Isoprostanes are a marker of oxidant stress and atherosclerotic risk, and plasma concentrations are elevated in obesity. Adiponectin is a regulator of insulin sensitivity, and low circulating levels are associated with oxidant stress and obesity. The aim of this study was to determine the effect of vitamin E supplementation on plasma concentrations of 8-isoprostane and adiponectin in overweight/obese subjects.

Aged garlic extract improves endothelial function in men with coronary artery disease.

Endothelium-dependent vasodilation is impaired and predicts the risk of a coronary event in patients with coronary artery disease (CAD). Oxidant stress and increased systemic inflammation may contribute to this endothelial dysfunction. Aged garlic extract (AGE) contains antioxidant compounds and increases nitric oxide production and decreases the output of inflammatory cytokines from cultured cells.

Hypochlorous acid and 3,4-dihydroxyphenylalanine increase the formation of serum protein lipofuscin-like fluorophores in vitro.

Introduction: Serum protein lipofuscin-like fluorophores (LLFs) that include fluorescent advanced glycation end products (AGEs), are an index of protein modification and levels are abnormally high in hemodialysis patients. To investigate the possibility that hypochlorous acid (HOCl) and 3,4-dihydroxyphenylalanine (DOPA) may contribute to high LLFs concentrations, we have examined the effect of these factors on serum protein LLF formation in vitro.

Methods: Protein LLF concentration was measured at excitation 350 nm and emission 460 nm and was expressed in arbitrary units relative to quinine sulphate fluorescence.

Effect of high-dose vitamin E on insulin resistance and associated parameters in overweight subjects.

Objective: Markers of oxidative stress and plasma alanine transferase (ALT) levels are increased and circulating antioxidant concentrations are reduced in individuals with insulin resistance. Vitamin E improves glycemic control in people with diabetes. We tested the hypothesis that vitamin E would decrease markers of oxidative stress and plasma ALT levels and improve insulin sensitivity in overweight individuals.

Acute effect of drinking red and white wines on circulating levels of inflammation-sensitive molecules in men with coronary artery disease.

There is evidence that moderate consumption of red wine with its high content of polyphenolic antioxidants may be more protective than white wine against development of coronary artery disease (CAD). The aim of this study was to compare the acute effects of ingestion of red wine and white wine on markers of inflammation in men with CAD. Thirteen men with angiographically-proven CAD were studied in a cross-over trial.

Hypochlorous acid and low serum paraoxonase activity in haemodialysis patients: an in vitro study.

Background: Serum paraoxonase 1 (PON1) is an oxidant-sensitive enzyme associated with high-density lipoprotein (HDL) that inhibits the atherogenic oxidation of low-density lipoprotein (LDL). In haemodialysis patients, production of reactive oxygen species, such as hypochlorous acid (HOCl) and hydrogen peroxide, is increased and serum PON1 arylesterase is abnormally low. We have examined the effect of HOCl and the uraemic milieu on serum PON1 arylesterase activity and the ability of HDL to inhibit LDL oxidation in vitro.

Serum protein-bound 3,4-dihydroxyphenylalanine and related products of protein oxidation and chronic hemodialysis.

Introduction: Protein-bound dihydroxyphenylalanine (PB-DOPA) and its oxidation products are formed by free radical and oxidative attack on proteins. Hemodialysis and uremic toxins can activate leukocytes leading to overproduction of reactive oxygen species such as hydrogen peroxide and hypochlorous acid (HOCl) that increases protein oxidation.

Methods: We have used a sensitive fluorometric method to measure PB-DOPA and its oxidation products in proteins after gamma-irradiation and incubation with HOCl and in serum from hemodialysis patients and healthy controls.

HRT does not improve urinary albumin excretion in postmenopausal diabetic women.

The effect of 6 months combined, continuous hormone replacement therapy (HRT) with conjugated equine oestrogen (0.625 mg) and medroxyprogesterone acetate (2.5 mg) on albumin/creatinine ratio (ACR) was determined in postmenopausal diabetic women in a randomised, controlled study.

Release of cholesterol from cell membranes to postprandial plasma from mildly hypercholesterolemic subjects: the effect of meals rich in olive and safflower oils.

Triglyceride-rich lipoproteins increase net transport of cell cholesterol to postprandial plasma from healthy subjects after a meal rich in fat and cholesterol. The aim of the present study was to determine the effect of meals rich in polyunsaturated fats (PUFA) and monounsaturated fats (MUFA) and low in cholesterol on net in vitro transport of cholesterol from red blood cells (RBCs) to postprandial plasma from 21 men with mild to moderate hypercholesterolemia in a randomized, crossover trial. Cholesterol concentration increased by 12% due to accumulation of cell cholesterol in fasted hypercholesterolemic plasma incubated with a 2/1 (vol/vol) excess of RBCs at 37 degrees C for 18 hours.

Effect of meals rich in heated olive and safflower oils on oxidation of postprandial serum in healthy men.

The present randomised, crossover study sought to determine the effect of meals rich in safflower oil and olive oil (60 g) which had been heated for 8 h at 210 degrees C and the corresponding unheated oils on copper ion oxidation of dilute serum from 16 healthy men. Four hours after the meals rich in the heated oils, there were significant decreases of similar magnitude (-12%) in the lag time in conjugated diene formation during diluted serum oxidation. In the 12 subjects who consumed meals containing unheated oils, the lag time also decreased (-11%) significantly after the meal rich in unheated safflower oil (US) and did not change significantly after the unheated olive oil (UO) meal and these changes were different between the meals at a marginal level of significance (P=0.