Early molecular oxidative stress biomarkers of ischemic penumbra in acute stroke.

Objectives: To assess whether plasma biomarkers of oxidative stress predict diffusion-perfusion mismatch in patients with acute ischemic stroke (AIS).

Methods: We measured plasma levels of oxidative stress biomarkers such as F2-isoprostanes (F2-isoPs), total and perchloric acid Oxygen Radical Absorbance Capacity (ORAC and ORAC), urinary levels of 8-oxo-7,8-dihydro-2'-deoxyguoanosine, and inflammatory and tissue-damage biomarkers (high-sensitivity C-reactive protein, matrix metalloproteinase-2 and -9) in a prospective study of patients with AIS presenting within 9 hours of symptom onset. Diffusion-weighted (DWI) and perfusion-weighted (PWI) MRI sequences were analyzed with a semiautomated volumetric method.

Polyphenols in Almond Skins after Blanching Modulate Plasma Biomarkers of Oxidative Stress in Healthy Humans.

Almond skins are a waste byproduct of blanched almond production. Polyphenols extracted from almond skins possess antioxidant activities in vitro and in vivo. Thus, we examined the pharmacokinetic profile of almond skin polyphenols (ASP) and their effect on measures of oxidative stress.

Oxidative Stress Biomarkers of Brain Damage: Hyperacute Plasma F2-Isoprostane Predicts Infarct Growth in Stroke.

Background And Purpose: Oxidative stress is an early response to cerebral ischemia and is likely to play an important role in the pathogenesis of cerebral ischemic injury. We sought to evaluate whether hyperacute plasma concentrations of biomarkers of oxidative stress, inflammation, and tissue damage predict infarct growth (IG).

Methods: We prospectively measured plasma F2-isoprostane (F2-isoP), urinary 8-oxo-7,8-dihydro-2'-deoxyguoanosine, plasma oxygen radical absorbance capacity assay, high sensitivity C reactive protein, and matrix metalloproteinase 2 and 9 in consecutive patients with acute ischemic stroke presenting within 9 hours of symptom onset.

Effect of almond consumption on vascular function in patients with coronary artery disease: a randomized, controlled, cross-over trial.

Objective: Almonds reduce cardiovascular disease risk via cholesterol reduction, anti-inflammation, glucoregulation, and antioxidation. The objective of this randomized, controlled, cross-over trial was to determine whether the addition of 85 g almonds daily to a National Cholesterol Education Program (NCEP) Step 1 diet (ALM) for 6 weeks would improve vascular function and inflammation in patients with coronary artery disease (CAD).

Research Design And Methods: A randomized, controlled, crossover trial was conducted in Boston, MA to test whether as compared to a control NCEP Step 1 diet absent nuts (CON), incorporation of almonds (85 g/day) into the CON diet (ALM) would improve vascular function and inflammation.

White matter hyperintensity volume correlates with matrix metalloproteinase-2 in acute ischemic stroke.

Background: White matter hyperintensity (WMH), a common radiographic finding associated with stroke risk and outcome, has been linked to matrix metalloproteinase (MMP) activity and increased levels of oxidative stress in nonstroke populations. We sought to determine whether WMH severity is associated with plasma levels of MMPs and oxidative stress (F2-isoprostane) in subjects with acute ischemic stroke (AIS).

Methods: We measured plasma biomarker levels at baseline and 48 hours in consecutive AIS subjects.

Flavonoid intake and eye health.

In the modern era of evidence-based scientific medicine, there is little recognition of centuries of shaman observational evidence. Yet it is extremely difficult to conduct long duration controlled studies of large populations. The controversy surrounding the issue of flavonoid bioactivity and alleged benefits for eye health is also plagued by natural product industry marketing efforts that rely on small, often poorly designed studies.

Effects of cranberry juice consumption on vascular function in patients with coronary artery disease.

Background: Cranberry juice contains polyphenolic compounds that could improve endothelial function and reduce cardiovascular disease risk.

Objective: The objective was to examine the effects of cranberry juice on vascular function in subjects with coronary artery disease.

Design: We completed an acute pilot study with no placebo (n = 15) and a chronic placebo-controlled crossover study (n = 44) that examined the effects of cranberry juice on vascular function in subjects with coronary artery disease.

Anthocyanins are bioavailable in humans following an acute dose of cranberry juice.

Research suggests that anthocyanins from berry fruit may affect a variety of physiological responses, including endothelial function, but little information is available regarding the pharmacokinetics of these flavonoids in humans. To determine the pharmacokinetics of cranberry anthocyanins, a study was undertaken in 15 participants (age: 62 +/- 8 y) with coronary artery disease. Blood and urine samples were collected between baseline (0 h) and 4 h after consumption of 480 mL cranberry juice (54% juice; 835 mg total polyphenols; 94.

Xenobiotic metabolism and berry flavonoid transport across the blood-brain barrier.

A compelling body of literature suggests berry phytochemicals play beneficial roles in reversing age-related cognitive impairment and protect against neurodegenerative disorders. Anthocyanins are bioactive phytochemicals in berries suspected to be responsible for some of these neuroprotective effects. The plausible mechanisms of anthocyanin bioactivity in brain tissue are dependent on their bioavailability to the brain.

Recent research on polyphenolics in vision and eye health.

A long-standing yet controversial bioactivity attributed to polyphenols is their beneficial effects in vision. Although anecdotal case reports and in vitro research studies provide evidence for the visual benefits of anthocyanin-rich berries, rigorous clinical evidence of their benefits is still lacking. Recent in vitro studies demonstrate that anthocyanins and other flavonoids interact directly with rhodopsin and modulate visual pigment function.

Dietary blueberry attenuates whole-body insulin resistance in high fat-fed mice by reducing adipocyte death and its inflammatory sequelae.

Adipose tissue (AT) inflammation promotes insulin resistance (IR) and other obesity complications. AT inflammation and IR are associated with oxidative stress, adipocyte death, and the scavenging of dead adipocytes by proinflammatory CD11c+ AT macrophages (ATMPhi). We tested the hypothesis that supplementation of an obesitogenic (high-fat) diet with whole blueberry (BB) powder protects against AT inflammation and IR.

Identification of anthocyanins in the liver, eye, and brain of blueberry-fed pigs.

Dietary intervention with anthocyanins may confer benefits in brain function, including vision. Research to date indicates that animals have only a limited capacity to absorb anthocyanins, compared to other types of flavonoids. Pigs, which are a suitable model for human digestive absorption, were used to examine the deposition of anthocyanins in tissues including the liver, eye, and brain tissue.

Antioxidant activity and metabolite profile of quercetin in vitamin-E-depleted rats.

Dietary antioxidants interact in a dynamic fashion, including recycling and sparing one another, to decrease oxidative stress. Limited information is available regarding the interrelationships in vivo between quercetin and vitamin E. We investigated the antioxidant activity and metabolism of quercetin (Q) in 65 F-344 rats (n=13 per group) randomly assigned to the following vitamin E (VE)-replete and -deficient diets: (a) VE replete (30 mg alpha-tocopherol acetate/kg diet) control ad libitum (C-AL), (b) VE replete pair fed (C-PF), (c) VE replete+5.

Avenanthramides are bioavailable and have antioxidant activity in humans after acute consumption of an enriched mixture from oats.

The consumption of polyphenols is associated with a decreased risk of cardiovascular disease. Avenanthramides (AV), alkaloids occurring only in oats, may have anti-atherosclerotic activity, but there is no information concerning their bioavailability and bioactivity in humans. We characterized the pharmacokinetics and antioxidant action of avenanthramide A, B, and C in healthy older adults in a randomized, placebo-controlled, 3-way crossover trial with 1-wk washout periods.

Effect of almond skin polyphenolics and quercetin on human LDL and apolipoprotein B-100 oxidation and conformation.

Almond skin polyphenolics (ASP) and vitamin C (VC) or E (VE) inhibit the Cu(2+)-induced generation of conjugated dienes in human low-density lipoprotein (LDL) in a synergistic manner. However, the mechanism(s) by which this synergy occurs is unknown. As modification of apolipoprotein (apo) B-100 is an early, critical step in LDL oxidation, we examined the effects of combining ASP or quercetin and antioxidant vitamins on the oxidation of this moiety as well as on the alteration of LDL conformation and electronegativity (LDL-).

Bilberry (Vaccinium myrtillus) anthocyanins modulate heme oxygenase-1 and glutathione S-transferase-pi expression in ARPE-19 cells.

Purpose: To determine whether anthocyanin-enriched bilberry extracts modulate pre- or posttranslational levels of oxidative stress defense enzymes heme-oxygenase (HO)-1 and glutathione S-transferase-pi (GST-pi) in cultured human retinal pigment epithelial (RPE) cells.

Methods: Confluent ARPE-19 cells were preincubated with anthocyanin and nonanthocyanin phenolic fractions of a 25% enriched extract of bilberry (10(-6)-1.0 mg/mL) and, after phenolic removal, cells were oxidatively challenged with H(2)O(2).

Determination of flavonoids and phenolics and their distribution in almonds.

Limited information is available concerning the qualitative and quantitative composition of polyphenolic compounds, especially flavonoids, in almonds. We determined total phenols, flavonoids, and phenolic acids in California almond (Prunus dulcis) skins and kernels among the principal almond varieties (Butte, Carmel, Fritz, Mission, Monterey, Nonpareil, Padre, and Price) with high-performance liquid chromatography (HPLC)/electrochemical detection and UV detection. Liquid chromatography/tandem mass spectrometry under identical HPLC conditions was utilized to verify identities of the predominant flavonoids and phenolic acids.

Rat gastrointestinal tissues metabolize quercetin.

Quercetin and quercetin glycosides from food or dietary supplements appear in body tissues almost exclusively as glucuronated, sulfated, and methylated quercetin conjugates, suggesting that the in vivo bioactivity of quercetin may be due to its metabolites. In this study, pre- and postabsorptive metabolism of orally ingested quercetin was examined by comparing the metabolite pattern in gastrointestinal (GI) tissues, contents, and internal tissues. F344 rats (n = 6) were fed for 6 wk a diet containing 0.

Flavonols, flavones, flavanones, and human health: epidemiological evidence.

Polyphenolic flavonoids are among a wide variety of phytochemicals present in the human diet. Basic research, animal model, and human studies suggest flavonoid intake may reduce the risk of several age-related chronic diseases. The vast number of flavonoids and mixtures of their subclasses, including flavonols, flavones, and flavanones, and the variety of agricultural practices that affect their concentration in foods have presented a challenge to the development of adequate food composition databases for these compounds.

Antioxidant status and biomarkers of oxidative stress in dogs with congestive heart failure.

Alterations in antioxidant status and oxidative stress have been documented in dogs with dilated cardiomyopathy (DCM). The purpose of this study was to more broadly assess this relationship in dogs with congestive heart failure (CHF). Malondialdehyde (MDA), 8-F(2alpha)-isoprostane, protein carbonyls, reduced (GSH) and oxidized (GSSG) glutathione, vitamins A, C, and E, and oxygen radical absorbance capacity (ORAC) were measured from a single venous blood sample from dogs with CHF secondary to DCM or chronic valvular disease (CVD) and in healthy controls.

Flavonoids from almond skins are bioavailable and act synergistically with vitamins C and E to enhance hamster and human LDL resistance to oxidation.

Consumption of tree nuts such as almonds has been associated with a reduced risk of coronary heart disease. Flavonoids, found predominantly in the skin of almonds, may contribute to their putative health benefit, but their bioactivity and bioavailability have not previously been studied. Almond skin flavonoids (ASF) were extracted with HCl:H2O:methanol (1:19:80) and their content of catechins and flavonols identified by HPLC with electrochemical detection.

Development of biomarkers based on diet-dependent metabolic serotypes: practical issues in development of expert system-based classification models in metabolomic studies.

Dietary restriction (DR)-induced changes in the serum metabolome may be biomarkers for physiological status (e.g., relative risk of developing age-related diseases such as cancer).

Dietary iron promotes azoxymethane-induced colon tumors in mice.

There is accumulating evidence that high levels of dietary iron may play a role in colon carcinogenesis. We used a mouse model to investigate the impact of elevated dietary iron on incidence of aberrant crypt foci (ACF; a preneoplastic lesion) on tumor formation and on induction of oxidative stress. A/J mice were injected intraperitoneally, once a week for 6 weeks, with the colonotropic carcinogen, azoxymethane (AOM) or saline (vehicle controls).

Flavonoid-rich dark chocolate improves endothelial function and increases plasma epicatechin concentrations in healthy adults.

Background: Dark chocolate derived from the plant (Theobroma cacao) is a rich source of flavonoids. Cardioprotective effects including antioxidant properties, inhibition of platelet activity, and activation of endothelial nitric oxide synthase have been ascribed to the cocoa flavonoids.

Objective: To investigate the effects of flavonoid-rich dark chocolate on endothelial function, measures of oxidative stress, blood lipids, and blood pressure in healthy adult subjects.

Avenanthramides and phenolic acids from oats are bioavailable and act synergistically with vitamin C to enhance hamster and human LDL resistance to oxidation.

The intake of phenolic acids and related polyphenolic compounds has been inversely associated with the risk of heart disease, but limited information is available about their bioavailability or mechanisms of action. Polyphenolics, principally avenanthramides, and simple phenolic acids in oat bran phenol-rich powder were dissolved in HCl:H(2)O:methanol (1:19:80) and characterized by HPLC with electrochemical detection. The bioavailability of these oat phenolics was examined in BioF1B hamsters.