Effects of diets high in corn oil or in extra virgin olive oil on oxidative stress in an experimental model of breast cancer.

Experimental evidence highlights the importance of dietetic factors on breast cancer. In this work we aimed to analyze the effects two oils, corn oil (rich in n-6 polyunsaturated fatty acids -PUFA-) and extra virgin olive oil (EVOO), on oxidative stress in an animal model of breast carcinogenesis. Female rats were fed a low-fat control, a high-corn oil, or a high-EVOO diet from weaning or after induction with 7,12-dimethylbenz[a]anthracene at 53 days. Animals were euthanized at 36, 51, 100 and 246 days of age. We analyzed antioxidant enzymes (mRNA and activity of superoxide dismutase, glutathione peroxidase and catalase), non-enzymatic capacity (oxidized and reduced glutathione) and DNA damage (8-oxo-dG) in tumors and mammary gland at different ages. We also analyzed lipid peroxidation (isoprostanes in serum and lipofuscin in liver). Results indicated a decrease in the enzymatic antioxidant capacity and increased oxidative stress in mammary gland of healthy young animals after a short period of high-fat diets intake, followed by an adaptation to chronic dietary intervention. After induction both diets, especially the one high in n-6 PUFA, increased the oxidized glutathione. In tumors no clear effects of the high-fat diets were observed, although in the long-term lipofuscin and 8-oxo-dG suggested greater oxidative damage by effect of the n-6 PUFA-rich diet. Considering the differential effects of these diets on mammary carcinogenesis that we have previously reported, this study suggests that these high-fat diets could have an effect on oxidative stress that would lead to different signaling pathways.

Influence of feeding thermally peroxidized soybean oil on growth performance, digestibility, gut integrity, and oxidative stress in nursery pigs.

The objectives of the current experiments were to evaluate the effect of feeding soybean oil (SO) with different levels of peroxidation on lipid, N, and GE digestibility, gut integrity, oxidative stress, and growth performance in nursery pigs. Treatments consisted diets containing 10% fresh SO (22.5 °C) or thermally processed SO (45 °C for 288 h, 90 °C for 72 h, or 180 °C for 6 h), each with an air infusion of 15 L/min, with postprocessing peroxide values of 7.6, 11.5, 19.1, and 13.4 mEq/kg and p-anisidine values of 1.92, 6.29, 149, and 159, for the 22.5 °C, 45 °C, 90 °C and 180 °C processed SO, respectively. In experiment 1, 64 barrows (7.1 ± 0.9 kg initial BW) were randomly allotted into 2 rooms of 32 pens and individually fed their experimental diets for 21 d, with a fresh fecal sample collected on day 20 for determination of GE and lipid digestibility. In experiment 2, 56 barrows (BW 9.16 ± 1.56 kg) were placed into individual metabolism crates for assessment of GE, lipid, and N digestibility and N retention. Urinary lactulose to mannitol ratio was assessed to evaluate in vivo small intestinal integrity, and urine and plasma were collected to analyze for markers of oxidative stress. Pigs were subsequently euthanized to obtain liver weights and analyze the liver for markers of oxidative stress. In experiment 1, pigs fed the SO thermally processed at 90 °C had reduced ADG (P = 0.01) and ADFI (P = 0.04) compared to pigs fed the other SO treatment groups, with no differences noted among pigs fed the 22.5 °C, 45 °C, and 180 °C SO treatments. No effects of feeding thermally processing SO on dietary GE or lipid digestibility (P > 0.10) were noted in either experiment. In experiment 2, there was no dietary effect of feeding peroxidized SO on the DE:ME ratio, N digestibility, or N retained as a percent of N digested, on the urinary ratio of lactulose to mannitol, on serum, urinary, or liver thiobarbituric acid reactive substances, on plasma protein carbonyls, or on urinary or liver 8-OH-2dG (P > 0.10). In experiment 2, pigs fed the SO thermally processed at 90 °C had the greatest isoprostane concentrations in the serum (P ≤ 0.01) and urine (P ≤ 0.05) compared to pigs fed the unprocessed SO. These results indicate that the change in fatty acid composition and/or the presence of lipid peroxidation products in peroxidized SO may reduce ADG and ADFI in nursery pigs, but appears to have no impact on GE, lipid, or N digestibility, or gut permeability. These data suggest that the presence of lipid peroxidation products may affect certain markers of oxidative stress.

Omega-3 Fatty Acid Supplementation is Associated With Oxidative Stress and Dyslipidemia, but Does not Contribute to Better Lipid and Oxidative Status on Hemodialysis Patients.

OBJECTIVE: The aim of the study was to explore the effects of n-3 polyunsaturated fatty acids (PUFA) supplementation in physiological doses on oxidative stress (OS) and dyslipidemia in patients on hemodialysis (HD). DESIGN AND METHODS: Randomized, double-blind, controlled, experimental trial. A total of 88 HD patients ≥18 years old and on HD for at least 6 months. A total of 43 patients received 1.28 g/day of n-3 PUFA, and 45 other patients received soybean oil for 12 weeks. Both oil supplements were vitamin E standardized. Routine tests, lipid profile, advanced oxidation protein products, isoprostanes, vitamins C and E, total antioxidant capacity, serum fatty acids, and adverse effects were evaluated. RESULTS: Supplementation was not able to alter lipid or OS profiles. There was an increase in the serum n-3 PUFA levels (eicosapentaenoic acid: +116%; docosahexaenoic acid: +100%) and an improvement in the n-6/n-3 ratio (-49%) in the supplemented group. Associations between n-3 PUFA and improvement in isoprostane and advanced oxidation protein product and HDL were observed. Treatment was well tolerated. CONCLUSION: Although the n-3 PUFA supplementation was associated with lower concentrations of isoprostane and advanced oxidation protein product and higher HDL levels, it was not sufficient for the improvement of highly prevalent risk factors, such as OS and dyslipidemia in HD patients.

Effect of iron supplementation during lactation on maternal iron status and oxidative stress: A randomized controlled trial.

We examined the effect of iron-containing prenatal vitamin-mineral supplements taken postpartum on biomarkers of iron status and oxidative stress. Lactating women (n = 114) were randomly assigned to consume daily one iron-free prenatal vitamin-mineral supplement plus either 27 mg of iron or placebo for approximately 3.5 months. The placebo group took the tablets between meals, while those given iron took the tablets either with (Fe-W) or between meals (Fe-B). Blood and urine samples were collected before and after the supplementation period to analyze hemoglobin (Hb), ferritin, hepcidin, transferrin saturation (TfSat), total plasma iron, and biomarkers of oxidative stress (isoprostane and 8-hydroxy-2-deoxyguanosine (8-OHdG)) and inflammation (C-reactive protein (CRP) and alpha-1-acid glycoprotein (AGP)). There was a trend toward a greater change in Hb among women in the Fe-B group compared to placebo (+2.5 vs. -3.7 g/L, respectively, p = 0.063). When the iron groups were combined, there was a greater change in Hb (+1.4 g/L) compared to placebo (p = 0.010). There were trends toward greater changes in TfSat (p = 0.087) and total plasma iron (p = 0.065) in the iron groups compared to placebo, yet no significant differences between the three groups in change in hepcidin (p = 0.291), isoprostane (p = 0.319), or 8-OHdG (p = 0.659), nor in change in ferritin among those with elevated CRP at baseline (60% of women; p = 0.946); among those without elevated CRP (40% of women), ferritin increased more in the iron groups compared to placebo (p = 0.001). Iron consumption during lactation moderately increased iron status, particularly among women without elevated CRP, and increased Hb, but did not significantly increase oxidative stress.

Simultaneous quantitative profiling of 20 isoprostanoids from omega-3 and omega-6 polyunsaturated fatty acids by LC-MS/MS in various biological samples.

Isoprostanoids are a group of non-enzymatic oxygenated metabolites of polyunsaturated fatty acids. It belongs to oxylipins group, which are important lipid mediators in biological processes, such as tissue repair, blood clotting, blood vessel permeability, inflammation and immunity regulation. Recently, isoprostanoids from eicosapentaenoic, docosahexaenoic, adrenic and α-linolenic namely F3-isoprostanes, F4-neuroprostanes, F2-dihomo-isoprostanes and F1-phytoprostanes, respectively have attracted attention because of their putative contribution to health. Since isoprostanoids are derived from different substrate of PUFAs and can have similar or opposing biological consequences, a total isoprostanoids profile is essential to understand the overall effect in the testing model. However, the concentration of most isoprostanoids range from picogram to nanogram, therefore a sensitive method to quantify 20 isoprostanoids simultaneously was formulated and measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The lipid portion from various biological samples was extracted prior to LC-MS/MS evaluation. For all the isoprostanoids LOD and LOQ, and the method was validated on plasma samples for matrix effect, yield of extraction and reproducibility were determined. The methodology was further tested for the isoprostanoids profiles in brain and liver of LDLR(-/-) mice with and without docosahexaenoic acid (DHA) supplementation. Our analysis showed similar levels of total F2-isoprostanes and F4-neuroprostanes in the liver and brain of non-supplemented LDLR(-/-) mice. The distribution of different F2-isoprostane isomers varied between tissues but not for F4-neuroprostanes which were predominated by the 4(RS)-4-F4t-neuroprostane isomer. DHA supplementation to LDLR(-/-) mice concomitantly increased total F4-neuroprostanes levels compared to F2-isoprostanes but this effect was more pronounced in the liver than brain.

High 15-F2t-Isoprostane Levels in Patients with a Previous History of Nonmelanoma Skin Cancer: The Effects of Supplementary Antioxidant Therapy.

BACKGROUND: Phase I of this study was aimed at comparing the profiles of oxidative stress biomarkers in patients with history of nonmelanoma skin cancer (NMSC), previously treated with surgery, to the healthy subjects. Phase II aimed to evaluate the effects of supplementary antioxidant therapy on the levels of biomarkers in the case group. MATERIALS AND METHODS: In Phase I, oxidative stress biomarkers were measured in blood samples obtained from 24 healthy subjects and 60 patients with history of NMSC previously treated with surgery. In Phase II, the 60 patients with history of NMSC were randomized into two subgroups, one receiving placebo (n = 34) and the other (n = 26) receiving vitamin C, vitamin E, and zinc supplementation for 8 weeks, followed by reevaluation of biomarkers. RESULTS: In Phase I, patients with history of NMSC showed increased plasma concentrations of all biomarkers, but only 15-F2t-isoprostane was significantly higher than in the healthy subjects. Risk of NMSC increased by 4% for each additional 1 pg/mL increase in 15-F2t-isoprostane. In Phase II, supplementation did not significantly reduce levels of oxidative stress biomarkers. CONCLUSION: Patients with history of NMSC had significantly high 15-F2t-isoprostane plasma levels; supplementation did not result in significant reduction of oxidative stress biomarkers. This trial was registered with ClinicalTrials.gov (ID NCT02248584).

Oxidative Stress Biomarkers and Incidence of Postoperative Atrial Fibrillation in the Omega-3 Fatty Acids for Prevention of Postoperative Atrial Fibrillation (OPERA) Trial.

BACKGROUND: Animal study results point to oxidative stress as a key mechanism triggering postoperative atrial fibrillation (PoAF), yet the extent to which specific biomarkers of oxidative stress might relate to PoAF risk in humans remains speculative. METHODS AND RESULTS: We assessed the association of validated, fatty acid-derived oxidative stress biomarkers (F2-isoprostanes, isofurans, and F3-isoprostanes) in plasma and urine, with incident PoAF among 551 cardiac surgery patients. Biomarkers were measured at enrollment, the end of surgery, and postoperative day 2. PoAF lasting ≥30 seconds was confirmed with rhythm strip or electrocardiography and centrally adjudicated. Outcomes were assessed until hospital discharge or postoperative day 10, whichever occurred first. Urine level of each oxidative stress biomarker rose at the end of surgery (2- to 3-fold over baseline, P<0.001) and subsequently declined to concentrations comparable to baseline by postoperative day 2. In contrast, plasma concentrations remained relatively stable throughout the perioperative course. Urine F2-isoprostanes and isofurans at the end of surgery were 20% and 50% higher in subjects who developed PoAF (P≤0.009). While baseline biomarker levels did not associate significantly with PoAF, end of surgery and postoperative day 2 isoprostanes and isofurans demonstrated relatively linear associations with PoAF. For example, the end of surgery extreme quartile multivariate adjusted OR (95% CI) for urine isofurans and F3-isoprostanes were 1.95 (1.05 to 3.62; P for trend=0.01) and 2.10 (1.04 to 2.25, P for trend=0.04), respectively. The associations of biomarkers with PoAF varied little by demographics, surgery type, and medication use (P≥0.29 for each). CONCLUSIONS: These novel results add to accumulating evidence supporting the likely key pathogenic role of elevated oxidative stress in PoAF. CLINICAL TRIAL REGISTRATION: URL: Clinicaltrials.gov Unique identifier: NCT00970489.

Special Issue on "Analytical Methods for Oxidized Biomolecules and Antioxidants" The use of isoprostanoids as biomarkers of oxidative damage, and their role in human dietary intervention studies.

Isoprostanoids are a group of non-enzymatic oxidized lipids from polyunsaturated fatty acids. They are commonly used as biomarkers for oxidative damage, to assess in vivo lipid peroxidation in diseases related to the vascular system and neurodegeneration. Currently, there is a mismatch with the outcome in the use of these biomarkers in intervention studies, particularly when testing the effect of antioxidants such as vitamins C and E, or zinc, or a cocktail of these, with other food components. Much of this is because the biomarkers, the method of measurement, and the duration of supplementation are unsuitable. In this review, we will highlight the formation of isoprostanoids from their respective fatty acids, and their application as biomarkers for oxidative damage in vivo, considering human dietary intervention studies evaluating plasma and urine, using mass spectrometry techniques.

Fermented soy permeate reduces cytokine level and oxidative stress in streptozotocin-induced diabetic rats.

Oxidative stress and inflammation are involved in the development of type 1 diabetes and its complications. Because two compounds found in soy, that is, isoflavones and alpha-galactooligosaccharides, have been shown to exert antioxidant and anti-inflammatory effects, this study aimed to assess the effects of a dietary supplement containing these two active compounds, the fermented soy permeate (FSP). We hypothesized that FSP would be able to reduce in vivo oxidative stress and inflammation in streptozotocin (STZ)-induced type 1 diabetic rats. Thirty male Wistar rats were divided into the control placebo, diabetic placebo, and diabetic FSP-supplemented groups. They received daily, by oral gavage, water (placebo groups) or diluted FSP (0.1 g/day; FSP-supplemented group). After 3 weeks, glycemic regulation (glycemia and fructosamine level); the plasma level of carboxymethyllysine (CML), a marker of systemic oxidative stress in diabetes; and the plasma levels of inflammatory markers (CRP, IL-1ß, IL-6, and uric acid) were evaluated. Markers of oxidative damage (isoprostanes and GSH/GSSG), antioxidant enzymatic activity (SOD and GPX), and Mn-SOD content were determined in skeletal muscle (gastrocnemius). Diabetic placebo rats exhibited higher CML levels, lower SOD and GPX activities, and decreased Mn-SOD contents. FSP supplementation in diabetic animals normalized the CML and antioxidant enzymatic activity levels and tended to increase Mn-SOD expression. The markers of inflammation whose levels were increased in the diabetic placebo group were markedly decreased by FSP (IL-1ß: -75%, IL-6: -46%, and uric acid: -17%), except for CRP. Our results demonstrate that FSP exhibited antioxidant and anti-inflammatory properties in vivo in STZ-induced diabetic rats.

Altered erythrocyte membrane fatty acid profile in typical Rett syndrome: effects of omega-3 polyunsaturated fatty acid supplementation.

This study mainly aims at examining the erythrocyte membrane fatty acid (FAs) profile in Rett syndrome (RTT), a genetically determined neurodevelopmental disease. Early reports suggest a beneficial effects of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) on disease severity in RTT. A total of 24 RTT patients were assigned to ω-3 PUFAs-containing fish oil for 12 months in a randomized controlled study (average DHA and EPA doses of 72.9, and 117.1mg/kgb.w./day, respectively). A distinctly altered FAs profile was detectable in RTT, with deficient ω-6 PUFAs, increased saturated FAs and reduced trans 20:4 FAs. FAs changes were found to be related to redox imbalance, subclinical inflammation, and decreased bone density. Supplementation with ω-3 PUFAs led to improved ω-6/ω-3 ratio and serum plasma lipid profile, decreased PUFAs peroxidation end-products, normalization of biochemical markers of inflammation, and reduction of bone hypodensity as compared to the untreated RTT group. Our data indicate that a significant FAs abnormality is detectable in the RTT erythrocyte membranes and is partially rescued by ω-3 PUFAs.

Both selenium deficiency and modest selenium supplementation lead to myocardial fibrosis in mice via effects on redox-methylation balance.

SCOPE: Selenium has complex effects in vivo on multiple homeostatic mechanisms such as redox balance, methylation balance, and epigenesis, via its interaction with the methionine-homocysteine cycle. In this study, we examined the hypothesis that selenium status would modulate both redox and methylation balance and thereby modulate myocardial structure and function. METHODS AND RESULTS: We examined the effects of selenium-deficient (<0.025 mg/kg), control (0.15 mg/kg), and selenium-supplemented (0.5 mg/kg) diets on myocardial histology, biochemistry and function in adult C57/BL6 mice. Selenium deficiency led to reactive myocardial fibrosis and systolic dysfunction accompanied by increased myocardial oxidant stress. Selenium supplementation significantly reduced methylation potential, DNA methyltransferase activity and DNA methylation. In mice fed the supplemented diet, inspite of lower oxidant stress, myocardial matrix gene expression was significantly altered resulting in reactive myocardial fibrosis and diastolic dysfunction in the absence of myocardial hypertrophy. CONCLUSION: Our results indicate that both selenium deficiency and modest selenium supplementation leads to a similar phenotype of abnormal myocardial matrix remodeling and dysfunction in the normal heart. The crucial role selenium plays in maintaining the balance between redox and methylation pathways needs to be taken into account while optimizing selenium status for prevention and treatment of heart failure.

The short-term effects of antioxidant and zinc supplements on oxidative stress biomarker levels in plasma: a pilot investigation.

PURPOSE: To determine if short-term Age-Related Eye Disease Study (AREDS) antioxidant and zinc supplementation affects biomarkers of oxidative stress, possibly serving as a predictor of their efficacy. DESIGN: Prospective interventional case series. METHODS: Nineteen subjects, 12 with intermediate or advanced age-related macular degeneration (AMD) (AREDS categories 3 or 4) and 7 non-AMD controls, were admitted to the Vanderbilt General Clinical Research Center and placed on a controlled diet for 7 days. Antioxidant and zinc supplements were stopped 2 weeks prior to study enrollment. Dietary supplementation with 500 mg vitamin C, 400 IU vitamin E, 15 mg ß-carotene, 80 mg zinc oxide, and 2 mg cupric oxide per day was instituted on study day 2. Blood was drawn on study days 2 and 7, and plasma concentrations of cysteine (Cys), cystine (CySS), glutathione (GSH), isoprostane (IsoP), and isofuran (IsoF) were determined. RESULTS: Short-term AREDS supplementation significantly lowered mean plasma levels of CySS in participants on a regulated diet (P = .034). No significant differences were observed for Cys, GSH, IsoP, or IsoF. There were no significant differences between AMD patients and controls. CONCLUSIONS: This pilot interventional study shows that a 5-day course of antioxidant and zinc supplements can modify plasma levels of CySS, suggesting that this oxidative stress biomarker could help predict how likely an individual is to benefit from AREDS supplementation. Further, CySS may be useful for the evaluation of new AMD therapies, particularly those hypothesized to affect redox status.

Coenzyme Q(10) supplementation ameliorates inflammatory signaling and oxidative stress associated with strenuous exercise.

BACKGROUND: Exhausting exercise induces muscle damage associated with high production of free radicals and pro-inflammatory mediators. AIM: The objective of this study was to determine for the first time and simultaneously whether oral coenzyme Q(10) (CoQ(10)) supplementation can prevent over-expression of inflammatory mediators and oxidative stress associated with strenuous exercise. METHODS: The participants were classified in two groups: CoQ(10) group (CG) and placebo group (PG). The physical test consisted in a constant run (50 km) that combined several degrees of high effort (mountain run and ultra-endurance), in permanent climbing. RESULTS: Exercise was associated with an increase in TNF-α, IL-6, 8-hydroxy-2'-deoxyguanosine (8-OHdG), and isoprostane levels, revealing the degree of inflammation and oxidative stress induced. Oral supplementation of CoQ(10) during exercise was efficient reducing oxidative stress (decreased membrane hydroperoxides, 8-OHdG and isoprostanes generation, increased catalase, and total antioxidant status), which would lead to the maintenance of the cell integrity. Data obtained also indicate that CoQ(10) prevents over-expression of TNF-α after exercise, together with an increase in sTNF-RII that limits the pro-inflammatory actions of TNF. Moreover, CoQ(10) supplementation reduced creatinine production. CONCLUSIONS: CoQ(10) supplementation before strenuous exercise decreases the oxidative stress and modulates the inflammatory signaling, reducing the subsequent muscle damage.

PKCß inhibition with ruboxistaurin reduces oxidative stress and attenuates left ventricular hypertrophy and dysfunction in rats with streptozotocin-induced diabetes.

Oxidative stress plays critical roles in the development of diabetic cardiovascular complications, including myocardial hypertrophy. The ß isoform of PKC (protein kinase C) is preferentially overexpressed in the myocardium of diabetic subjects accompanied with increased activation of the pro-oxidant enzyme NADPH oxidase, which may exacerbate oxidative stress. We hypothesized that myocardial PKCß is a major upstream mediator of oxidative stress in diabetes and that PKCß inhibition can attenuate myocardial hypertrophy and dysfunction. Control or streptozotocin-induced diabetic rats were treated with the selective PKCß inhibitor RBX (ruboxistaurin; 1 mg/kg of body weight per day) or the antioxidant NAC (N-acetylcysteine) for 4 weeks. LV (left ventricular) dimensions and functions were detected by echocardiography. 15-F2t-isoprostane (a specific index of oxidative stress) and myocardial activities of superoxide dismutase as well as protein levels of NADPH oxidase were assessed by immunoassay or Western blotting. Echocardiography revealed that the LV mass/body weight ratio was significantly increased in diabetic rats (P<0.01 compared with the control group) in parallel with the impaired LV relaxation. A significant increase in cardiomyocyte cross-sectional area was observed in diabetic rats accompanied by an increased production of O2- (superoxide anion) and 15-F2t-isoprostane (all P<0.05 compared with the control group). RBX normalized these changes with concomitant inhibition of PKCß2 activation and prevention of NADPH oxidase subunit p67phox membrane translocation and p22phox overexpression. The effects of RBX were comparable with that of NAC, except that NAC was inferior to RBX in attenuating cardiac dysfunction. It is concluded that RBX can ameliorate myocardial hypertrophy and dysfunction in diabetes, which may represent a novel therapy in the prevention of diabetic cardiovascular complications.

Protective effects of Haematococcus astaxanthin on oxidative stress in healthy smokers.

Free radicals induced by cigarette smoking have been strongly linked to increased oxidative stress in vivo, contributing to the pathobiology of various diseases. This study was performed to investigate the effects of Haematococcus astaxanthin (ASX), which has been known to be a potent antioxidant, on oxidative stress in smokers. Thirty-nine heavy smokers (≥20 cigarettes/day) and 39 non-smokers were enrolled in this study. Smokers were randomly divided into three dosage groups to receive ASX at doses of 5, 20, or 40 mg (n=13, each) once daily for 3 weeks. Oxidative stress biomarkers such as malondialdehyde, isoprostane, superoxide dismutase, and total antioxidant capacity, and ASX levels in plasma were measured at baseline and after 1, 2, and 3 weeks of treatment. Compared with baseline, the plasma malondialdehyde and isoprostane levels decreased, whereas superoxide dismutase level and total antioxidant capacity increased in all ASX intervention groups over the 3-week period. In particular, isoprostane levels showed a significant dose-dependent decrease after ASX intake. The results suggest that ASX supplementation might prevent oxidative damage in smokers by suppressing lipid peroxidation and stimulating the activity of the antioxidant system in smokers.

F4-neuroprostanes mediate neurological severity in Rett syndrome.

BACKGROUND: Rett syndrome (RTT) is a pervasive development disorder, mainly caused by mutations in the methyl-CpG binding protein 2 (MeCP2) gene. No reliable biochemical markers of the disease are available. Here we assess F4-neuroprostanes (F4-NeuroPs), lipid peroxidation products of the docosahexaenoic acid, as a novel disease marker in RTT and correlate it with clinical presentation, MeCP2 mutation type, and disease progression. In addition, we investigate on the impact of ω-3 polyunsaturated fatty acids (ω-3 PUFAs) supplementation on F4-NeuroPs levels. METHODS: A case-control study design was used. A cohort of RTT patients (n=144) exhibiting different clinical presentations, disease stages, and MeCP2 gene mutations were evaluated. F4-NeuroPs were measured in free form using a GC/NICI-MS/MS technique. Plasma F4-NeuroPs levels in patients were compared to healthy controls and related to RTT forms, disease progression, and response to ω-3 PUFAs supplementation. RESULTS: Plasma F4-NeuroPs levels were i) higher in RTT than in controls; ii) increased with the severity of neurological symptoms; iii) significantly elevated during the typical disease progression; iv) higher in MeCP2-nonsense as compared to missense mutation carriers; v) higher in typical RTT as compared to RTT variants; and vi) decreased in response to 12 months ω-3 PUFAs oral supplementation. CONCLUSIONS: Quantification of plasma F4-NeuroPs provides a novel RTT marker, related to neurological symptoms severity, mutation type and clinical presentation.

Grape seed proanthocyanidin extract (GSPE) attenuates collagen-induced arthritis.

To examine whether grape seed proanthocyanidin extract (GSPE) which is known to act as an antioxidant has therapeutic effect on collagen-induced arthritis (CIA) in mice, an animal model of rheumatoid arthritis. Mice were treated with an intraperitoneal injection of GSPE (10, 50, or 100 mg/kg) or saline. Clinical, histological, and biochemical parameters were assessed. The effects of GSPE on osteoclastogenesis were determined by tartrate-resistant acid phosphatase (TRAP) staining of the inflamed joints and bone-marrow cells cultured with the receptor activator of nuclear factor B ligand (RANKL) and macrophage colony-stimulating factor (M-CSF). Intracellular levels of hydrogen peroxide were determined using carboxy-dichlorodihydrofluorescein diacetate. GSPE treatment significantly attenuated the severity of CIA in a dose-dependent manner and reduced the histology scores for synovial inflammation, cartilage erosion, bone erosion, and the number of TRAP+ osteoclasts. GSPE treatment significantly reduced the numbers of tumor necrosis factor alpha (TNF-alpha)- or interleukin 17 (IL-17)-producing cells in the synovial tissue and the spontaneous production of TNF-alpha and IL-17 by splenocytes compared with those in the control mice. The serum levels of type-II-collagen-specific IgG2a and plasma levels of 8-isoprostane in the GSPE-treated mice were significantly lower than those in the control mice. GSPE dose-dependently suppressed osteoclastogenesis in vitro. GSPE significantly reduced hydrogen peroxide production by anti-CD3-monoclonal-antibody-stimulated CD4+ splenocytes. These results indicate that intraperitoneal injection of GSPE attenuated CIA in mice. GSPE may be useful in the treatment of rheumatoid arthritis.

Marginal zinc deficiency increases magnesium retention and impairs calcium utilization in rats.

An experiment with rats was conducted to determine whether magnesium retention is increased and calcium utilization is altered by a marginal zinc deficiency and whether increased oxidative stress induced by a marginal copper deficiency exacerbated responses to a marginal zinc deficiency. Weanling rats were assigned to six groups of ten with dietary treatment variables of low zinc (5 mg/kg for 2 weeks and 8 mg/kg for 7 weeks), low copper (1.5 mg/kg), adequate zinc (15 mg/kg), and adequate copper (6 mg/kg). Two groups of rats were fed the adequate-zinc diet with low or adequate copper and pair-fed with corresponding rats fed the low-zinc diet. When compared to the pair-fed rats, marginal zinc deficiency significantly decreased the urinary excretion of magnesium and calcium, increased the concentrations of magnesium and calcium in the tibia, increased the concentration of magnesium in the kidney, and increased the urinary excretion of helical peptide (bone breakdown product). Marginal copper deficiency decreased extracellular superoxide dismutase and glutathione, which suggests increased oxidative stress. None of the variables responding to the marginal zinc deficiency were significantly altered by the marginal copper deficiency. The findings in the present experiment suggest that increased magnesium retention and impaired calcium utilization are indicators of marginal zinc deficiency.

Following 2 diet-restricted male outdoor rock climbers: impact on oxidative stress and improvements in markers of cardiovascular risk.

Lower body fat percentage is positively associated with climbing performance. This may lead climbers to practice unhealthy diet restriction when no sport-specific nutrition information exists. This study examined whether prolonged diet restriction affects body composition, oxidative stress, or other potential health risks in outdoor rock climbers. Two healthy male climbers conducted a 5 week rock climbing trip with a limited food budget ($1 each per day). Subjects underwent an energy restriction of approximately 40%. Loss of body weight and fat mass at week 5 were 5.8% and 16.1%, respectively, and were accompanied by significant subcutaneous fat loss in the iliac crest and abdomen. Triacylglycerols (TG), free fatty acids and C-reactive protein (CRP) dramatically decreased from baseline to week 2, and then maintained the lower level until week 5. Plasma vitamin C was below the normal range, and F2-isoprostanes, a marker of oxidative stress, continuously increased to week 5. Superoxide dismutase and glutathione peroxidase increased to week 2, but had returned to baseline levels at week 5. These results indicate that prolonged reduced energy intake while climbing may have an impact on weight loss and fat mass loss, which may contribute to low circulating TG and CRP, indicating improvements in markers of cardiovascular risk, and may lead to increased oxidative stress and reduced circulating antioxidants. Further studies are warranted to determine whether antioxidant supplementation or increased energy intake reduce oxidative stress.

Evaluation of the antioxidant effects of coffee and its components using the biomarkers hydroxyoctadecadienoic acid and isoprostane.

The association between coffee consumption and its antioxidant effects has not been elucidated in detail. In experimental animals, we used biomarkers to investigate the relationship between coffee consumption and its effects on oxidative stress. We propose a method in which both the free and ester forms of hydroperoxides and ketones as well as the hydroxides of linoleic acid are measured as total hydroxyoctadecadienoic acid (tHODE). Mice were divided into 6 groups: animals in 5 of these groups were fed a vitamin E-depleted diet [VE(-) group], whereas those in the 6(th) (control) group were fed a diet containing 0.002 wt% vitamin E [VE(+) group]. Different VE(-) groups were also administered coffee or drinking water that contained a coffee component-chlorogenic acid, caffeic acid, or caffeine-for 1 month. It was clearly demonstrated that the liver levels of tHODE in the VE(-) groups increased compared to the VE(+) group but that coffee consumption reduced these elevated levels to that of the control. Interestingly, the plasma and liver levels of the HODE stereoisomer ratio (Z,E/E,E), which is a measure of antioxidant capacity in vivo, were highest among the groups studied. These data, together with the values for antioxidant levels in vivo, indicate that the efficacy of antioxidants in vivo can be evaluated reasonably well based on the tHODE level and its stereoisomer ratio, and that the antioxidant capacity of coffee is superior to that of its individual components.