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The current study pioneers a comprehensive exploration into the influence of ripening stages on the nutritional composition and antioxidant attributes of the New Zealand damson plums (Prunus domestica ssp. Insititia). Sampled at early‐, mid‐, and late‐ripening stages from randomly selected plum trees, the investigation unveiled notable significant (p <.05) declines in multiple parameters as ripening progressed. Noteworthy reductions in dry matter (from 21% to 19.33%), stone weight (from 30.23% to 24.30%), total dietary fiber (from 3.15% to 2.5%), energy content (from 280 to 263 kJ/100 g), vitamin D3 (from 1.67 to 1.53 μg/100 g), vitamin A (from 4.2 to 3.87 μg/100 g), and specific minerals (e.g., Ca, Mg, and P) emerged as a hallmark of this progression. Additionally, plums harvested at the advanced ripening stage exhibited heightened moisture content in contrast to their early‐stage counterparts. Conversely, ash, protein, carbohydrates, total sugar, and minerals (including K, Na, Zn, and Se) demonstrated no significant alteration (p >.05) across ripening stages. Remarkably, damson plums that were harvested at the end of the ripening stage displayed reduced phenolic content and total antioxidant activity compared to those acquired at the early–mid ripening phase. This research collectively highlights the substantive impact of harvesting time and ripening stage on the nutritional and antioxidant profiles of damson plums cultivated in New Zealand. [ABSTRACT FROM AUTHOR]

Oxidative stress occurs when the body's antioxidant system is unable to prevent reactive oxygen species from causing cellular damage, and over the last two decades, oxidative stress has received extensive attention from behavioural ecologists investigating its links with life‐history traits including reproduction, growth, and immunity. Despite the breadth of studies examining oxidative stress in relation to animal behaviour, life‐history, and health, the role of oxidative stress in shaping variation in the cognitive abilities of wild animals has been almost entirely neglected. Here, I discuss how oxidative damage in the brain may affect cognitive performance in the wild, both directly and by mediating links to other life‐history traits. First, I outline evidence that the brain is particularly susceptible to oxidative stress and highlight medical studies demonstrating that oxidative damage impairs cognitive ability in humans and other animals. I then explore how oxidative stress may similarly affect cognition and behaviour in an ecological context, and the far‐reaching consequences this could have on wild animals' lives, including their fitness. Finally, I suggest methodological tools that could clarify the role of oxidative stress in cognitive ecology and approaches that combine existing ecological assays of behaviour and cognitive performance with bio‐medical experimental designs. While challenging to investigate, oxidative stress in the brains of wild animals may have profound consequences for their cognition and health, which currently remain almost entirely unexplored. [ABSTRACT FROM AUTHOR]

To construct food ingredients with improved bioactivities and physicochemical properties, two sericin hydrolysate–flavonoid conjugates, bearing quercetin and rutin covalently bound to sericin, were prepared under alkaline conditions. UV spectroscopy and SDS‐PAGE confirmed that sericin hydrolysate and oxidized flavonoids formed conjugates, which were primarily the result of covalent interactions. Changes and differences in molecular weight distribution, secondary and tertiary structures, surface hydrophobicity, and surface morphology were observed. Anti‐inflammatory activities were evaluated by basing on inhibitory activity against nitric oxide (NO) production and 15‐lipoxygenase (15‐LOX). The conjugates showed significantly improved (p <.05) anti‐inflammatory and emulsifying properties than unmodified sericin hydrolysate. Meanwhile, the covalent interaction had a positive effect on the antioxidant activity of sericin hydrolysate. Practical applications: We had prepared flavonoid–sericin hydrolysate conjugates and evaluated the effect of covalent binding of flavonoids on the physicochemical, anti‐inflammatory, antioxidant, and emulsifying properties of sericin hydrolysate, which is beneficial to broaden the range of applications of sericin and flavonoids in the food, cosmetics, and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

This study examined the secondary metabolite content and the antioxidant activities of hydromethanolic P. lentiscus L. leaves extracts at different altitudes. The results indicated that the contents of polyphenols and flavonoids were significantly (p ≤ 0.05) high in the low altitude, unlike the Chl (chlorophyll), tannins, and ascorbic acid, which were reported to have higher content in the high altitude. These results showed that the P. lentiscus L. is more adaptable to higher elevations than low elevation, where the plant was probably stressed. On the other hand, the analyses of correlation between the antioxidant activity and phytochemical content affirmed that the antiradical activity (DPPH) correlated with the content of polyphenols; however, the total antioxidant activity is correlated with the flavonoid content. These results revealed the importance of P. lentiscus L. leaves as a natural antioxidant and gave an idea of the altitude effect on the biochemical parameters of leaves. [ABSTRACT FROM AUTHOR]

Pulmonary hypertension (PH) is a global health issue with a prevalence of 10% in ages >65 years. Right heart failure (RHF) is the main cause of death in PH. We have previously shown that monocrotaline (MCT)‐induced PH and RHF are due to an increase in oxidative stress. In this study, probucol (PROB), a strong antioxidant with a lipid‐lowering property, versus lovastatin (LOV), a strong lipid‐lowering drug with some antioxidant effects, were evaluated for their effects on the MCT‐induced RHF. Rats were treated (I.P.) with PROB (10 mg/kg ×12) or LOV (4 mg/kg ×12), daily 6 days before and 6 days after a single MCT injection (60 mg/kg). Serial echocardiography was performed and at 4‐week post‐MCT, lung wet‐to‐dry weight, hemodynamics, RV glutathione peroxidase (GSHPx), superoxide dismutase (SOD), catalase, lipid peroxidation, and myocardial as well as plasma lipids were examined. MCT increased RV systolic and diastolic pressures, wall thickness, RV end diastolic diameter, mortality, and decreased ejection fraction as well as pulmonary artery acceleration time. These changes were mitigated by PROB while LOV had no effect. Furthermore, PROB prevented lipid peroxidation, lowered lipids, and increased GSHPx and SOD in RV myocardium. LOV did decrease the lipids but had no effect on antioxidants and lipid peroxidation. A reduction in oxidative stress and not the lipid‐lowering effect of PROB may explain the prevention of MCT‐induced PH, RHF, and mortality. Thus targeting of oxidative stress as an adjuvant therapy is suggested. [ABSTRACT FROM AUTHOR]

Previously, beetroot is mainly consumed as a food additive. In recent years, the beetroot, especially the betalains (betanin) and nitrates it contains, now has received increasing attention for their effective biological activity. Betalains have been proven to eliminate oxidative and nitrative stress by scavenging DPPH, preventing DNA damage, and reducing LDL. It also has been found to exert antitumor activity by inhibiting cell proliferation, angiogenesis, inducing cell apoptosis, and autophagy. In some chronic diseases, nitrate is the main component for lowing blood lipids, glucose, and pressure, while its role in treating hypertension and hyperglycemia has not been clearly stated. Moreover, the intake of nitrate‐rich beetroot could enhance athletic performance and attenuate muscle soreness in certain types of exercise. The objective of this review is to provide sufficient evidence for the clarification of health benefits of beetroot, especially in the aspect of biooxidation, neoplastic diseases, some chronic diseases, and energy supplementation. [ABSTRACT FROM AUTHOR]

Context. Chaptalia nutans (L.) Pol. (family: Asteraceae) is widely used in traditional medicine as laxative and anticough medications and especially in the traumatisms, wounds, and hemorrhages in topical preparations. Objective. This work was to evaluate the chemical constitution of the hydromethanolic (30/70 methanol-water) macerating extract obtained from the leaves of C. nutans, as well as to study the antioxidant, antimicrobial, cytotoxic, and genotoxic activity of the species. Materials and methods. Phytochemical screening, antioxidant activity (total phenolic, total flavonoid, condensed tannins content, DPPH radical, and FRAP), antibacterial activity (P. aeruginosa, B. cereus, E. epidermidis, E. coli, S. aureus, E. faecalis, P. mirabilis, Candida glabrata (clinical isolate), Candida tropicalis (clinical isolate), C. krusei (clinical isolate), and C. albicans (clinical isolate)), and oxidative stress parameters (TBARS, carbonyl protein, and DCFH) were analyzed according to the literature. Toxicity of C. nutans was evaluated using an alternative method, D. melanogaster, as well as a locomotor assay. Results. The phytochemical screening test of methanolic leaves extract revealed the presence of alkaloids, coumarins, quaternary bases, phenolics, flavonoids, tannins, and free steroids. A quantitative phytochemical study indicated the total phenol (30.17 ± 1.44 mg/g), flavonoid (21.64 ± 0.66 mg/g), and condensed tannins (9.58 ± 0.99 mg/g). DPPH (345.41 ± 5.35 μg/mL) and FRAP (379.98 ± 39.25 μM FeSO4/mg sample) show to extract of C. nutans leaves an intermediate value, indicating moderate antioxidant activity of the extract. Antibacterial results revealed only a positive result (antimicrobial activity) for the hexane fraction which significantly inhibited the microorganisms E. epidermidis, C. tropicalis, C. glabrata, and C. krusei at a concentration of 1000 μg/mL. TBARS, carbonyl protein, and DCFH demonstrate that the extract has the ability to protect the cell from protein and lipid damage, as well as the inhibition of oxygen-derived radicals at the three concentrations tested: 0.1, 1, and 10 mg/mL. Regarding the toxicity of C. nutans extract against D. melanogaster, it was found that until the concentration of 15 mg/mL, the extract showed no toxicity and that the LC50 obtained was 24 mg/mL. Results show that the C. nutans extract leaves used to prevent PQ damage were effective in reducing flies' mortality and improving locomotor capacity. Conclusion. Our studies demonstrated for the first time that C. nutans crude leaf extract has high antioxidant capacity both in vitro and in vivo through different analysis techniques. These results make it possible to infer future applications in the pharmacological area, evidenced by the low toxicity observed in D. melanogatser, as well as the ability to neutralize different sources of RONS. [ABSTRACT FROM AUTHOR]

Several studies investigated the impact of pycnogenol on blood pressure. Nevertheless, the results are inconclusive. The aim of the present systematic review and meta-analysis was to clarify the effect of pycnogenol supplementation on blood pressure. PubMed, Scopus, Web of Science, and Google Scholar were systematically searched until March 2018 to find clinical trials, which examined the effect of pycnogenol supplementation on systolic and diastolic blood pressure in adults. A subgroup analysis was applied to find out potential sources of interstudy heterogeneity. A total of 12 clinical trials (922 participants) were included in the meta-analysis. Pooled analysis suggested that pycnogenol supplementation can reduced systolic blood pressure (SBP) of (-3.22 mmHg; 95% CI [-5.52, -0.92]) and diastolic blood pressure (DBP; -1.91 mmHg; 95% CI [-3.64, -0.18]). Effect of pycnogenol on SBP was more pronounce in subgroup in which pycnogenol was administered along with other treatments. A significant effect of pycnogenol on DBP in studies with >12-week duration, whereas this favorable effect was not observed in subgroup with ≤12-week supplementation. The present systematic review and meta-analysis suggest that pycnogenol had a favorable effect on SBP and DBP. Further, high quality randomized clinical trials are needed to confirm this result. [ABSTRACT FROM AUTHOR]

The objective of this research was twofold: first, to optimize the extraction process of Lonicera japonica polyphenols using a response surface methodology, and second, to study the antioxidant activity and tyrosinase inhibitory capacity of the polyphenols of different purities. High‐speed shearing homogenization extraction was used to extract the polyphenols from L. japonica. The antioxidant activity and the effect of polyphenols on tyrosinase activity were studied using free radical scavenging assay and the tyrosinase method, respectively. The optimal extraction conditions with an extraction yield of 6.96% for polyphenols were determined as follows: ethanol volume fraction 57%, shearing time 3.30 min, and solid–liquid ratio 1:58. Lonicera japonica polyphenols exhibited potent scavenging activity on 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and 2, 2'‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS), and inhibitory capacity on tyrosinase. The results suggested that L. japonica polyphenols could be explored as a natural antioxidant and tyrosinase inhibitor. [ABSTRACT FROM AUTHOR]

The aim of the present study was a comparative investigation of water and 70% ethanol extracts derived from yellow and red onion (Allium cepa L.) peels against diabetes and diabetic complications. The total phenolic contents (TPCs) and total flavonoid contents (TFCs) of each cultivar, measured to assess phytochemical characteristics, showed a direct correlation with the in vitro antioxidant effects. Among the two captives, the yellow onion peel extract showed higher antioxidant activity than red one. However, all extracts exhibited significant protein tyrosine phosphatase 1B (PTP1B) inhibitory activity (IC50; 0.30–0.86 μg/ml), showing water extracts more potent (IC50; approximately 0.3 μg/mL), than the 70% ethanol extracts (IC50; approximately 0.8 μg/ml). Similarly, in insulin‐resistant HepG2 cells, all extracts enhanced the glucose uptake and reduced the expression of PTP1B in a concentration‐dependent manner, water extract displaying better activity. Our results overall suggest that in vitro antioxidant and antidiabetic potentials vary among red and yellow cultivars and extracting solvents, which could therefore be a promising strategy to prevent diabetes and associated complications. The present study provides an insight into the bioactivity of waste onion peel toward diabetes and diabetic complications. Furthermore, the varying degree of TPC and TFC in different solvent extracts of two cultivars was compared and correlated with their potency. Overall result of the present study demonstrated onion peel as good food source to prevent diabetes and diabetic complications. [ABSTRACT FROM AUTHOR]

Abstract: Flavonoids are plant‐derived dietary components with a substantial impact on human health. Research has expanded massively since it began in the 1930s, and the complex pathways involved in bioavailability of flavonoids in the human body are now well understood. In recent years, it has been appreciated that the gut microbiome plays a major role in flavonoid action, but much progress still needs to be made in this area. Since the first publications on the health effects of flavonoids, their action is understood to protect against various stresses, but the mechanism of action has evolved from the now debunked simple direct antioxidant hypothesis into an understanding of the complex effects on molecular targets and enzymes in specific cell types. This review traces the development of the field over the past 8 decades, and indicates the current state of the art, and how it was reached. Future recommendations based on this historical analysis are (a) to focus on key areas of flavonoid action, (b) to perform human intervention studies focusing on bioavailability and protective effects, and (c) to carry out cellular in vitro experiments using appropriate cells together with the chemical form of the flavonoid found at the site of action; this could be the native form of compounds found in the food for studies on digestion and the intestine, the conjugated metabolites found in the blood after absorption in the small intestine for studies on cells, or the chemical forms found in the blood and tissues after catabolism by the gut microbiota. [ABSTRACT FROM AUTHOR]

Abstract: Resveratrol is a natural phytoestrogen with neuroprotective properties. Polyphenolic compounds including resveratrol exert in vitro antioxidant, anti‐inflammatory, and antiamyloid effects. Resveratrol and its derivative pterostilbene are able to cross the blood‐brain barrier and to influence brain activity. The present short review summarizes the available evidence regarding the effects of these polyphenols on pathology and cognition in animal models and human subjects with dementia. Numerous investigations in cellular and mammalian models have associated resveratrol and pterostilbene with protection against dementia syndromes such as Alzheimer's disease (AD) and vascular dementia. The neuroprotective activity of resveratrol and pterostilbene demonstrated in in vitro and in vivo studies suggests a promising role for these compounds in the prevention and treatment of dementia. In comparison to resveratrol, pterostilbene appears to be more effective in combatting brain changes associated with aging. This may be attributed to the more lipophilic nature of pterostilbene with its two methoxyl groups compared with the two hydroxyl groups of resveratrol. The findings of available intervention trials of resveratrol in individuals with mild cognitive impairment or AD do not provide evidence of neuroprotective or therapeutic effects. Future clinical trials should be conducted with long‐term exposure to preparations of resveratrol and pterostilbene with high bioavailability. © 2017 BioFactors, 44(1):83–90, 2018 [ABSTRACT FROM AUTHOR]

Type 2 diabetes mellitus is a worldwide epidemic and its atherosclerotic complications determine the high morbidity and mortality of diabetic patients. Caffeic acid (CAF), a phenolic acid present in normal diets, is known for its antioxidant properties. The aim of this study was to investigate CAF's anti-inflammatory properties and its mechanism of action, using cultured human endothelial cells (HEC) incubated with glycated low-density lipoproteins (gLDL). Levels of the receptor for advanced glycation end-products (RAGE), inflammatory stress markers (C reactive protein, CRP; vascular cell adhesion molecule-1, VCAM-1; monocyte chemoattractant protein-1, MCP-1), and oxidative stress and endoplasmic reticulum stress (ERS) markers were evaluated in gLDL-exposed HEC, in the presence/absence of CAF. RAGE silencing or blocking, specific inhibitors for oxidative stress (apocynin, N-acetyl-cysteine), and ERS (salubrinal) were used. The results showed that: (i) gLDL induced CRP synthesis and secretion through mechanisms involving NADPH oxidase-dependent oxidative stress and ERS in HEC; (ii) gLDL-RAGE interaction, oxidative stress, and ERS stimulated the secretion of VCAM-1 and MCP-1 in HEC; and (iii) CAF reduced the secretion of CRP, VCAM-1, and MCP-1 in gLDL-exposed HEC by inhibiting RAGE expression, oxidative stress, and ERS. In conclusion, CAF might be a promising alternative to ameliorate a wide spectrum of disorders due to its complex mechanisms of action resulting in anti-inflammatory and antioxidative properties. © 2017 BioFactors, 43(5):685-697, 2017 [ABSTRACT FROM AUTHOR]

Milk antioxidants, both lipophilic (conjugated linoleic acid, α-tocopherol, β-carotene, vitamins A and D3, coenzyme Q10, phospholipids) and hydrophilic antioxidants (proteins, peptides, vitamins, minerals and trace elements) play a key role in maintaining pro-oxidant and antioxidant homeostasis in the human body. Lipophilic antioxidants are characterised by high thermal stability and they are active in all dairy products. Lipophilic and hydrophilic antioxidants interact in the process of deactivating reactive oxygen species and the final products of lipid peroxidation. A negative correlation between milk consumption and the incidence of diet-dependent diseases confirms that the consumption of milk and dairy products delivers health benefits. [ABSTRACT FROM AUTHOR]

Present study was designed to compare the potential effects of high serum levels of LDL and oxidised LDL (Ox LDL) on spermatogenesis parameters in male Wistar rats. Animals were allocated into three groups and were fed for 14 weeks with normal, cholesterol-rich and oxidised cholesterol-rich diets. Blood lipid profile, sex hormones level, as well as sex organs weight were evaluated. The sex organs weight in oxidised cholesterol-fed group was significantly reduced ( P < 0.05). Spermatozoa count in the group with high serum concentration of Ox LDL (64 ± 4.2 × 106) was markedly lower ( P < 0.01) than that of normal rats (87 ± 4.1 × 106) and rats with high serum level of LDL (90 ± 6.3 × 106). Similarly, the percentage of viable spermatozoa was significantly ( P < 0.001) decreased from 78% to 52% by high level of Ox LDL in serum. While, nonoxidised LDL did not have suppressive effects on spermatogenesis and organs weight. Consistent with these effects, the serum concentration of sex hormones including FSH ( P < 0.001), LH ( P < 0.001) and testosterone ( P < 0.01) was significantly decreased only in rats with high level of Ox LDL but not in rats with high level of nonoxidised LDL. In conclusion, high Ox LDL level showed higher destructive effect on reproductive system compared to the high LDL level. [ABSTRACT FROM AUTHOR]

Low seminal plasma concentrations of coenzyme Q10 (CoQ10) have been correlated with impaired sperm parameters, but the exact mechanism remains of dominating interest. This randomised, placebo-controlled study examined the effect of CoQ10 on catalase, superoxide dismutase ( SOD) and F2-isoprostanes in seminal plasma in infertile men and their relation with CoQ10 concentration. Sixty infertile men with idiopathic oligoasthenoteratozoospermia ( OAT) were randomised to receive 200 mg d−1 of CoQ10 or placebo for 3 months. 47 persons of them completed the study. Semen analysis, anthropometric measurements, diet and physical activity assessment were performed for subjects before and after treatment. Independent and paired t-test, chi-square test and ancova were compared outcomes of supplementation between two groups. CoQ10 levels increased from 44.74 ± 36.47 to 68.17 ± 42.41 ng ml−1 following supplementation in CoQ10 ( P < 0.001). CoQ10 group had higher catalase and SOD activity than the placebo group. There was a significant positive correlation between CoQ10 concentration and normal sperm morphology ( P = 0.037), catalase ( P = 0.041) and SOD ( P < 0.001). Significant difference was shown between the mean of changes in seminal plasma 8-isoprostane in two groups ( P = 0.003) after supplementation. Three-month supplementation with CoQ10 in OAT infertile men can attenuate oxidative stress in seminal plasma and improve semen parameters and antioxidant enzymes activity. [ABSTRACT FROM AUTHOR]

Animal feed provides a range of antioxidants that help the body building an integrated antioxidant system responsible for a prevention of damaging effects of free radicals and products of their metabolism. Vitamin E is considered to be the main chain-breaking antioxidant located in the membranes and effectively protecting them against lipid peroxidation. Recently, various polyphenol compounds, especially flavonoids, have received substantial attention because of their antioxidant activities in various in vitro systems. However, it was shown that flavonoid compounds are poorly absorbed in the gut and their concentrations in target tissues are too low to perform an effective antioxidant defences. The aim of the present paper is to review existing evidence about possible roles of various plant extracts provided with the diet in animal/poultry nutrition with a specific emphasis to their antioxidant activities. [ABSTRACT FROM AUTHOR]

Coenzyme Q10 (CoQ10) provides the energy for vital cellular functions and is known to act as an antioxidant. We conducted an open label study to examine the clinical effects of supplementation of the reduced form of CoQ10, ubiquinol, in addition to conventional glucose-lowering agents in patients with type 2 diabetes. Nine subjects (3 males and 6 females) with type 2 diabetes and receiving conventional medication were recruited. The subjects were assigned to receive an oral dose of 200 mg ubiquinol daily for 12 weeks. The effect of ubiquinol on blood pressure, lipid profile, glycemic control, oxidative stress, and inflammation were examined before and after ubiquinol supplementation. In addition, five healthy volunteers were also assigned to receive an oral dose of 200 mg ubiquinol daily for 4 weeks to examine the effects of ubiquinol on insulin secretion. In patients with diabetes, there were no differences with respect to blood pressure, lipid profile, oxidative stress marker, and inflammatory markers. However, there were significant improvements in glycosylated hemoglobin (53.0 ± 4.3 to 50.5 ± 3.7 mmol/mol, P = 0.01) (7.1 ± 0.4 to 6.8 ± 0.4%, P = 0.03). In healthy volunteers, the insulinogenic index (0.65 ± 0.29 to 1.23 ± 0.56, P = 0.02) and the ratio of proinsulin to insulin were significantly improved (3.4 ± 1.8 to 2.1 ± 0.6, P = 0.03). The results of our study are consistent with the suggestion that the supplementation of ubiquinol in subjects with type 2 diabetes, in addition to conventional antihyperglycemic medications, improves glycemic control by improving insulin secretion without any adverse effects.© 2012 International Union of Biochemistry and Molecular Biology, Inc. [ABSTRACT FROM AUTHOR]

J. Neurochem. (2011) 119, 909-919. Abstract The brain is highly vulnerable to oxidative stress, thus controlling oxidative stress is considered to be an important therapeutic target for neurodegenerative diseases. In this study, we found that two isoflavone metabolites (tectorigenin and glycitein) inhibited hydrogen peroxide-induced reactive oxygen species (ROS) generation and subsequent cell death in rat primary astrocytes. The isoflavone metabolites increased the expression of phase II antioxidant enzymes, such as hemeoxygenase-1 (HO-1) and NAD(P)H:quinone oxidoreductase 1 (NQO1), and pre-treatment of cells with their specific inhibitors or small interfering RNA (siRNA) reversed the antioxidant and cytoprotective effects of isoflavones. The results suggest that the antioxidant/cytoprotective effects of isoflavone metabolites are at least because of increased HO-1 and NQO1 expression. Further mechanistic studies revealed that isoflavones increase the binding of transcription factors [nuclear factor-E2-related factor 2 (Nrf2) and c-Jun] to the antioxidant response element (ARE) on HO-1 and NQO1 promoters. Down-regulation of Nrf2 and/or c-Jun using dominant-negative mutants (DNMs) or siRNA diminished the expression of HO-1 and NQO1, suggesting that Nrf2 and c-Jun are key transcription factors modulating HO-1/NQO1 expression. Moreover, PI3 kinase and mitogen-activated protein kinase (MAPK) signaling pathways were shown to be involved in HO-1 and/or NQO1 expression by isoflavones. Our data collectively suggest that HO-1 and NQO1 play a critical role in antioxidant effects of isoflavone metabolites in rat brain astrocytes. [ABSTRACT FROM AUTHOR]

Studies in vitro and in mice indicate a role for Coenzyme Q (CoQ) in gene expression. To determine this function in relationship to physiological readouts, a 2-week supplementation study with the reduced form of CoQ (ubiquinol, QH, 150 mg/d) was performed in 53 healthy males. Mean CoQ plasma levels increased 4.8-fold after supplementation. Transcriptomic and bioinformatic approaches identified a gene-gene interaction network in CD14-positive monocytes, which functions in inflammation, cell differentiation, and peroxisome proliferator-activated receptor-signaling. These QH-induced gene expression signatures were also described previously in liver tissues of SAMP1 mice. Biochemical and NMR-based analyses showed a reduction of low density lipoprotein (LDL) cholesterol plasma levels after QH supplementation. This effect was especially pronounced in atherogenic small dense LDL particles (19-21 nm, 1.045 g/L). In agreement with gene expression signatures, QH reduces the number of erythrocytes but increases the concentration of reticulocytes. In conclusion, QH induces characteristic gene expression patterns, which are translated into reduced LDL cholesterol levels and altered parameters of erythropoiesis in humans. © 2011 IUBMB IUBMB Life, 63(1): 42-48, 2011 [ABSTRACT FROM AUTHOR]

Nearly after one century of research and thousands of publications, the physiological function(s) of vitamin E remain unclear. Available evidence suggests a role in cell homeostasis that occurs through the modulation of specific signaling pathways and genes involved in proliferative, metabolic, inflammatory, and antioxidant pathways. Vitamin E presence in the human body is under close metabolic control so that only α-tocopherol and, to a lower extent, γ-tocopherol are retained and delivered to tissues. Other vitamin E forms that are not retained in the body in significant amounts, exhibit responses in vitro that are different form those of α-tocopherol and may include tumor cell specific toxicity and apoptosis. These responses provide a therapeutic potential for these minor forms, either as such or metabolically modified, to produce bioactive metabolites. These cellular effects go beyond the properties of lipophilic antioxidant attributed to α-tocopherol particularly investigated for its alleged protective role in atherosclerosis or other oxidative stress conditions. Understanding signaling and gene expression effects of vitamin E could help assign a physiological role to this vitamin, which will be discussed in this review. Besides vitamin E signaling, attention will be given to tocotrienols as one of the emerging topics in vitamin E research and a critical re-examination of the most recent clinical trials will be provided together with the potential use of vitamin E in disease prevention and therapy. [ABSTRACT FROM AUTHOR]

Docosahexaenoic acid (DHA) can prevent cardiovascular events. However, few studies have addressed the effects of DHA on both platelet reactivity and redox status in healthy subjects, and dose-related studies are scarce. The main objectives of the present study were to determine the effects of increasing doses of DHA on platelets and redox status in humans. Twelve healthy male volunteers (aged 53-65 yr) were assigned to consume an intake of successively 200, 400, 800, and 1600 mg/d DHA, as the only ω-3 fatty acid, for 2 wk each dose. Blood and urine samples were collected before and after each dose of DHA and at 8 wk after arrest of supplementation. DHA was incorporated in a dose-response fashion in platelet phospholipids. After supplementation with 400 and 800 mg/d DHA, platelet reactivity was significantly decreased. Platelet vitamin E concentration increased only after 200 mg/d DHA, while p38 MAP kinase phosphorylation decreased. Urinary isoprostane was also significantly lowered after 200 mg/d DHA but was increased after 1600 mg/d. Therefore, supplementation with only 200 mg/d DHA for 2 wk induced an antioxidant effect. It is concluded that low consumption of DHA could be an effective and nonpharmacological way to protect healthy men from platelet-related cardiovascular events. [ABSTRACT FROM AUTHOR]

The role of nutritional supplementation is of increasing interest with regard to ocular disease. Randomised controlled trials have demonstrated the effectiveness of supplementation for age-related macular degeneration, and formulations are now being developed for use by people with diabetes and diabetic retinopathy. The aim of this review was to synthesise the evidence for use of nutritional supplementation in type 2 diabetes. MEDLINE and EMBASE databases were searched using a systematic approach. Only double-masked randomised controlled trials were selected. A total of 50 trials were identified as suitable for inclusion. The potential role of alpha-lipoic acid, chromium, folic acid, isoflavones, magnesium, Pycnogenol®, selenium, vitamin C, vitamin E, and zinc in the treatment of type 2 diabetes is discussed. The review of trials identifies positive effects of these nutrients on various outcome measures relating to insulin resistance and cardiovascular factors. Chromium was the most studied supplement, accounting for 16 of the 50 trials. A majority of the trials found a positive effect of chromium on fasting plasma glucose. Isoflavones were found to have a positive effect on insulin resistance and cardiovascular outcome measures, but only when combined with soy proteins. Vitamin E is reported to reduce oxidative stress at levels of 200 mg day−1 or more. [ABSTRACT FROM AUTHOR]

Cholesterol oxidation products (COPs) have been considered as specific in vivo markers of oxidative stress. In this study, an increased oxidative status was induced in Wistar rats by feeding them a high-fat diet (cafeteria diet). Another group of animals received the same diet supplemented with a combination of two different antioxidants, ascorbic acid (100 mg/kg rat/day) and sodium selenite (200 μg/kg rat/day) and a third group fed on a control diet. Total and individual COPs analysis of the different diets showed no differences among them. At the end of the experimental trial, rats were sacrificed and serum cholesterol, triglycerides and COPs were measured. None of the diets induced changes in rats body weight, total cholesterol and triglycerides levels. Serum total COPs in rats fed on the high-fat diet were 1.01 μg/ml, two times the amount of the control rats (0.47 μg/ml). When dietary antioxidant supplementation was given, serum total COPs concentration (0.44 μg/ml) showed the same levels than those of the rats on control diet. 7β-hydroxycholesterol, formed non-enzymatically via cholesterol peroxidation in the presence of reactive oxygen species, showed slightly lower values in the antioxidant-supplemented animals compared to the control ones. This study confirms the importance of dietary antioxidants as protective factors against the formation of oxysterols. [ABSTRACT FROM AUTHOR]

Background Anti-oxidants are of growing interest in early treatment and prevention of allergic diseases in early life, but the effects on allergen-specific immune responses need to be documented further before intervention studies in infants are undertaken. The aim of this study in adults was to determine the effects of dietary anti-oxidants on allergen-specific immune responses in sensitized individuals. Methods In a randomized controlled trial, 54 allergic adults received an anti-oxidant supplement ( n=36) comprising β-carotene (9 mg/day), vitamin C (1500 mg/day), vitamin E (130 mg/day), zinc (45 mg/day), selenium (76 μg/day) and garlic (150 mg/day) or a placebo ( n=18) for 4 weeks. Anti-oxidant capacity (AC), serum levels of vitamin C, vitamin E, β-carotene and selenium, peripheral blood responses, exhaled nitric oxide (eNO), as a marker of airway inflammation, and plasma F2 isoprostanes, as a measure of oxidative stress, were measured before and after supplementation. Results Anti-oxidant supplementation resulted in significant increases in serum levels of vitamin C, vitamin E, β-carotene and selenium levels, compared with the placebo group ( P<0.001). There was no change in serum AC, plasma F2-isoprostanes, eNO or immune responses following supplementation with anti-oxidants compared with placebo. Conclusion Supplementation with anti-oxidants resulted in significantly increased levels of vitamin C, vitamin E, β-carotene and selenium but no change in immune responses, serum AC or plasma F2-isoprostanes. [ABSTRACT FROM AUTHOR]

Background There has been growing interest in the role of antioxidant function in controlling inflammatory disease states, such as allergy. This study investigated the relationship between antioxidant status, markers of airways inflammation [exhaled nitric oxide (eNO)], oxidative stress (F2 isoprostanes) and immune responses in allergic adults. Methods Antioxidants (vitamins C, E, β-carotene and selenium) and total antioxidant capacity (tAC) in serum were examined in relation to eNO, plasma F2 isoprostanes and peripheral blood mononuclear cell (PBMC) cytokine and lymphoproliferative response to house dust mite (HDM) allergen, Staphylococcus enterotoxin B (SEB), phytohaemaglutinin (PHA) and lipopolysaccharide (LPS) in 54 allergic adults. Results Firstly, levels of specific vitamins did not correlate with tAC. Secondly, we did not see any evidence that specific vitamin levels (or tAC) were associated with either polarization or attenuation of in vitro immune responses. If anything, there were positive correlations between antioxidant (vitamin C and selenium) levels and HDM allergen responses [lymphoproliferation (selenium; r=0.35, P=0.013) and both Th2 IL13 (vitamin C; τ=0.254, P=0.028) and Th1 IFN-γ (vitamin C; τ=0.302, P=0.009) responses]. There were also significant positive relationships between antioxidant levels and IL-10 responses to polyclonal stimulation by SEB ( r=0.292, P=0.036) and LPS ( r=0.34, P=0.015) (β-carotene) and PHA ( r=0.34, P=0.021) (tAC). Thirdly, although airways inflammation (eNO) was associated with both in vitro and in vivo (skin test reactivity) to HDM, we did not see any correlation between eNO and oxidative stress (F2-isoprostanes). Finally, there were no consistent relationships between oxidative stress and immune responses. Conclusion There was no evidence that higher antioxidant levels were associated with reduced allergen responsiveness in allergic adults. If anything, antioxidant status was associated with increased immune responsiveness. The significance of this needs to be addressed in future intervention studies. [ABSTRACT FROM AUTHOR]

Extracts of Jiuqu Hongmei tea were prepared using distilled water, 25% ethanol, 50% ethanol, and 75% ethanol, respectively, and their antioxidant activities and protective capacity on HUVEC cells from damage induced by Na2S2O3 were investigated. All tea extracts exhibited remarkable antioxidant activity, especially E2 extracted by 25% ethanol, Pearson correlation analysis indicated theaflavins, total phenolics, and soluble sugar could be the possible effective components (p < 0.05). Meanwhile, extracts prepared by 25% ethanol and 75% ethanol showed notable protective abilities on HUVEC cells injured by Na2S2O3. Considering the application in functional foods development, 25% ethanol was shown to be a better solvent for retaining phytochemicals of Jiuqu Hongmei tea in this study. Practical applications: This research focused on the investigation of the antioxidant activities and HUVEC cell protective ability of Jiuqu Hongmei tea extracts prepared by four solvents. Selection of an ideal solvent which can effectively extract the compounds from Jiuqu Hongmei tea is critical, as it determines the amount and type of different compounds extracted. Our findings indicate that the Jiuqu Hongmei tea extracts have remarkble antioxidant potential (1,1‐diphenyl‐2‐picrylhydrazyl, ferric‐reducing antioxidant power, and 2,2′‐azino‐bis‐(3‐ethylbenzothiazoline‐6‐sulphonic acid) diammonium salt assay), as well as notable protective ability on HUVEC cells injured by Na2S2O3, especially the 25% ethanol extract. Hence, the 25% ethanol extract of Jiuqu Hongmei tea may play a promising role in health benefits, nutraceutical, and functional foods development. [ABSTRACT FROM AUTHOR]

The article presents abstracts and key phrases to various articles published in the 2003 issue of the periodical Nephrology. Increased expression of urotensin 2 and urotensin receptor GPR14 in human diabetic nephropathy by R.G. Langham, R. Gow, N.M. Thomson, J.K. Dowling and R.E. Gilbert. Role of advanced glycation end products in renal injury in diabetic apoE knockout mouse by Markus Lassila, Kwee Seah, Vicki Thallas, Riccardo Candido, Mark E. Cooper, Terri J. Allen and Karin Jandeleit-Dahm. Modulation of antioxidants enzyme expression by aminoguanidine in diabetic nephropathy by S.D. Ricardo, C.L. Hepper, A.J. Cox, R.E. Gilbert and D.J. Kelly.