High Concentrations Of Vitamin Research Articles

Vitamin C metabolites, independent of smoking status, significantly enhance leukocyte, but not plasma ascorbate concentrations

The objective of this study was to test the effects of acute doses of vitamin C alone, calcium ascorbate with vitamin C metabolites, and placebo, on total plasma and leukocyte vitamin C concentrations over 24 hours. A double-blind, placebo-controlled, four-way crossover study was performed consisting of four separate phases lasting 24 hours each and utilizing one of four oral 1000-mg preparations within each phase (one of vitamin C alone, two separate vitamin C formulations of calcium ascorbate with vitamin C metabolites, and placebo). There was a 7-day washout between phases, and blood draws at seven time points within each phase of the study for a total of 28 serologic measurements per subject and 420 total measurements for the entire clinical trial. Vitamin C concentration in plasma and leukocytes were measured by high-performance liquid chromatography at baseline and at six sequential time periods over 24 hours. Fifteen healthy males were enrolled, aged 18-39 years; nine were had never smoked and six were chronic smokers. No significant difference in plasma vitamin C levels was observed when comparing the different preparations. However, at 24 hours, calcium ascorbate with metabolites resulted in significantly higher concentrations of vitamin C in leukocytes (P<0.0001) compared with vitamin C alone. These results were similar for both metabolite formulations, and independent of smoking status. Regardless of smoking status, vitamin C metabolites may enhance leukocyte utilization of vitamin C itself, despite no consistent difference in plasma levels among the different preparations. A larger clinical investigation is warranted to confirm these preliminary findings, and to determine the clinical relevance of this impact on overall immune function.

Taxol synergizes with antioxidants in inhibiting hormal refractory prostate cancer cell growth

Taxanes are chemotherapeutic agents commonly used to treat various carcinomas. Dietary antioxidants, such as vitamin E, green tea extracts, and isoflavones have been used against prostate cancer, and exhibit anticancer effects both in vitro and in vivo. We evaluated the combined effect of taxol (paclitaxel) with pyrrolidine dithiocarbamate, vitamin E, epigallocatechin gallate, and genistein in killing hormone-refractory prostate cancer cells. Those agents were tested on the hormone-refractory prostate cancer cell line PC-3, and the viability of the cells was determined using MTT {3 (4, 5-dimethylthiazo-2-yl)-2, 5-diphenyl tetrazolium} assay after drug treatment. PC-3 cells were sensitive to these drugs with 50% inhibitory concentrations of 0.1, 23, 220, 1122, and 260 μM, for taxol, pyrrolidine dithiocarbamate, epigallocatechin gallate, genistein, and vitamin E, respectively. Genistein, pyrrolidine dithiocarbamate, and epigallocatechin gallate showed synergistic cytotoxicity to PC-3 cells when combined with 0.01 μM taxol. Only high concentration of vitamin E showed a synergistic effect with this dose of taxol. Further study revealed that 3 combinations could induce sub-G1 phase of cell cycle, induce apoptosis, and increase caspase activity and decrease Bcl-2 expression simultaneously. In conclusion, in addition to vitamin E, incorporation of these antioxidants with taxan-based cytotoxic therapies offers encouraging strategies for combating hormone-refractory prostate cancers.

Detrimental effects of high levels of antioxidant vitamins C and E on placental function: Considerations for the Vitamins in Preeclampsia (VIP) trial

Supplementation with antioxidant vitamins has been proposed to reduce the risk of preeclampsia and perinatal complications. In a recent study, it has been shown that this supplementation to above physiological doses does not reduce the risk of preeclampsia, but increases the rate of low birthweight babies, suggesting a detrimental effect on placental function, given the lower birthweight. The aim of the present study was to investigate the effects of high levels of antioxidants vitamins C and E on placental cells in vitro. Isolated fresh human cytotrophoblasts were exposed to high concentrations of vitamins C and E for 48 h. Then the secretion of human chorionic gonadotropin (hCG) and the production of tumor necrosis factor-alpha (TNF-alpha) were assessed. High levels of vitamins C and E, separately or combined, decrease the secretion of hCG by cytotrophoblasts and increase their production of TNF-alpha. Exposure of cytotrophoblasts to high levels of antioxidant vitamins C and E may affect placental function, as reflected by decreased secretion of hCG; and placental immunity, as reflected by increased production of TNF-alpha. Such alterations are known to lead to endothelial dysfunction and adverse pregnancy outcomes, such as fetal growth restriction (FGR).

Near-fatal bleeding, senna, and the opposite of lettuce

In February, 2006, a 45-year-old woman went to her local hospital with diff use abdominal pain. When the hospital realised that she might have a serious illness, she was brought by ambulance to our hospital, for insurance reasons. By the time she arrived, the pain had been present for 15 h. Her aortic valve had been replaced in 1999, but she had had no abdominal problems until mid-2005, when she developed a tendency to constipation. She had therefore taken 1–2 tablets of a senna-based laxative, once or twice a week. She had seen no need to tell her doctors about the laxative. For 3 weeks preceding her admission she had taken several tablets of laxative a day, and passed loose, watery stools up to three times a day. The day before the pain started, she had taken many tablets, after passing no stool for 2 days. She had then passed three watery stools, followed by three bloody stools— some blood was fresh and red, and some old and black. She had no other medical history of note; notably, she had no psychiatric disorder. She was on no drugs other than warfarin, which she had taken ever since her operation. She took her warfarin regularly, and her international normalised ratio (INR) had been in the therapeutic range for years. Her diet, including her consumption of green vegetables, varied little. She took no herbal medications. 25 days before admission, her INR had been 2·3. She was hypotensive and tachycardic. Her abdomen was distended, with widespread tenderness and guarding. Rectal examination revealed fresh blood. Blood tests showed a haemoglobin concentration of only 84 g/L; the platelet count was normal, at 164×109/L, but the INR was 11·9; the activated partial thromboplastin time was 92·4 s (control time 29·3 s). The concentrations of bilirubin and aspartate aminotransferase were slightly high, at 33·5 μmol/L and 48 U/L, respectively, but the results of liver function tests were otherwise normal. CT of the abdomen showed extensive haematoma in the pelvic, paracolic, and subhepatic regions. We admitted the patient for several days, during which we gave her vitamin K, fresh frozen plasma, and packed red cells. She subsequently resumed taking warfarin, and stopped taking laxatives in excess; her INR rapidly returned to the target range, where it has remained ever since. When last seen, in November, 2007, she was well. Vitamin K is an essential cofactor for γ-carboxylation, the post-translational modifi cation of coagulation factors II, VII, IX, and X (fi gure). Although vitamin K is also a cofactor for the γ-carboxylation of protein C and protein S, lack of vitamin K reduces coagulation. Green leafy vegetables have especially high con centrations of vitamin K, but the vitamin K in vegetable oils and soya may be more bioavailable. Many patients on warfarin are aware—as, indeed, was our patient—that their dietary consumption of vitamin K should remain fairly constant. However, not all are aware that diarrhoea can reduce absorption of vitamin K, and increase the risk of bleeding. Although some physicians recommend halving the dose of warfarin when the patient has diarrhoea, many doctors seem unaware of the increased risk of bleeding—and many textbooks, formularies, and patient-information leafl ets fail to mention the increased risk, or do so only in passing. Cases like ours will continue to occur, until doctors and patients are better informed.

Effects of injectable vitamins A, D, E and C on the health and growth rate of feedlot cattle destined for the Australian domestic market

To examine the effects of injectable vitamins A, D and E at feedlot entry on health and growth rate and the effects of injectable vitamin C at the time of treatment for bovine respiratory disease (BRD) on cattle health. Systematic allocation of 2465 cattle at feedlot entry to: a commercial vitamin A, D and E preparation at the label dose rate; commercial vitamin A, D and E at twice the label dose rate; a formulation with no vitamin D, a lower concentration of vitamin A and a higher concentration of vitamin E; and the oil-based carrier alone at volumes corresponding to the above treatments. Comparisons of growth rate, disease and mortality were made between the groups at the conclusion of the feeding period. In a separate experiment, 176 cattle were alternately administered injectable vitamin C at the time of treatment for BRD, or were not injected with vitamin C, and mortality was compared between the groups. There were no differences between cattle administered vitamin A, D and E at feedlot entry and the controls in growth rate (P=0.11), all diseases (P=0.99), BRD (P=0.60) or mortalities (P=0.95). Cattle treated with the higher vitamin E and lower vitamin A preparation had a higher (P=0.02) incidence of anorexia than the other groups. Fewer cattle treated with 5 g of vitamin C by intramuscular injection at the time of treatment with antibiotics for BRD subsequently died (P=0.04). The routine injection of cattle with vitamins A, D and E at feedlot entry is unlikely to result in improvements in health and growth rate where cattle are provided with these vitamins in their diets at concentrations equal to the National Research Council recommendations. Mortality rate in cattle diagnosed with BRD may be reduced by intramuscular injection of vitamin C at the time of treatment with antibiotics.

Composition and quality differences between the longissimus and infraspinatus muscles for several groups of pasture-finished cattle

Samples of longissimus (LT) and infraspinatus (IS) muscles from five contrasting groups of pasture-finished cattle (n=7/group) were assessed for quality and composition characteristics in order to determine whether features of pasture-finished beef reported previously apply across different muscles and different classes of cattle. The cattle were not raised together or slaughtered at the same time. Wagyu-cross steers had the highest intramuscular fat levels, particularly in the LT, followed by Angus steers, Charolais-cross steers and Belgian Blue-cross steers, with the lowest levels for Friesian bulls. Relative to the LT, the IS muscle had longer sarcomeres, higher cooking losses, higher concentrations of vitamin E, and lower myofibrillar fragmentation indexes, while its ultimate pH was slightly higher but less variable. Beef from Wagyu-cross steers had the highest chroma values and the lowest shear values, while Friesian bull beef was darkest and least tender. Intramuscular fatty acid composition and concentrations of bioactive compounds such as coenzyme Q10 and carnosine, were similar to those reported previously for cattle finished on New Zealand pastures although taurine levels were lower. Generally concentrations of bioactive compounds differed more between muscles and groups than between cattle finished on pasture or grain as reported previously.

Influence of light on health‐promoting phytochemicals of broccoli sprouts

AbstractBACKGROUND: Broccoli (Brassicaceae) is a rich source of phytochemicals (glucosinolates and phenolic compounds) and micronutrients (vitamins and minerals). Germinated broccoli sprouts contain much higher levels (10–100 times) of aliphatic (glucoraphanin) and indolic glucosinolates than the inflorescences. This quality characteristic of broccoli sprouts plays an important role in human health and disease prevention. Although it is known that genetic and environmental factors can affect the composition of broccoli inflorescences, the influence of such factors on the seeds and sprouts has not been widely reported. Therefore the aim of this study was to determine the effect of light versus dark growth conditions on the phytochemical composition (vitamin C, phenolic compounds and glucosinolates) of broccoli sprouts.RESULTS: Broccoli sprouts grown in the light were found to have much higher concentrations of vitamin C (by 83%), glucosinolates (by 33%) and phenolic compounds (by 61%) than those grown in the dark. During a 7 day period there was a clear and analogous trend in both treatments, with a general reduction in concentrations over time. Among the different organs studied (seeds, cotyledons, stems and roots), the cotyledons contained the highest levels of bioactive compounds, while the roots contained the lowest.CONCLUSION: Light treatment of sprouting broccoli seeds increased their concentration of health‐promoting phytochemicals, mainly during the first 3–5 days of development. Therefore the younger broccoli sprouts are a better source of bioactive compounds for the consumer than the inflorescences. Copyright © 2008 Society of Chemical Industry

Vitamin C Status in Iranian Children With Acute Lymphoblastic Leukemia: Evidence for Increased Utilization

Vitamin C status and total antioxidant capacity (TAC) in children with acute lymphoblastic leukemia (ALL) was assessed in 28 hospitalized patients and 30 apparently healthy control subjects. It was determined that whereas vitamin C intake in patients with ALL was more than twice as much as in controls, plasma and urinary concentrations of vitamin C were more than 10 times and 2.5 times higher in controls than in the patients with ALL, respectively (P < 0.001). Accordingly, serum TAC levels in the patients with ALL were lower than in healthy subjects (P < 0.001). Vitamin C utilization is increased in children with ALL.

Lack of antioxidative properties of vitamin C and pyruvate in cultured retinal pigment epithelial cells

Oxidative damage to the retinal pigment epithelium might be involved in the pathogenesis of age related macular degeneration. Thus antioxidative protection represents a rationale for a causative therapy or prophylaxis. The aim of the present study is to evaluate antioxidative properties of vitamin C and pyruvate at retinal pigment epithelial (RPE) cells exposed to oxidative stress. The ability of vitamin C and pyruvate to quench hydroxyl radicals was tested using the di-hydro-rhodamine (DHR) assay. Cells of the human RPE cell line ARPE-19 were exposed for 8 min to hydroxyl radicals generated by the Fenton reaction from 2.25 mM H2O2 and 30 microM Fe3+ -nitrilo-tri-acetate. This was done in the absence and presence of 0.3-3.0 mM pyruvate and vitamin C, respectively. Cell survival was analysed by vitality staining (life-dead-assay) and expressed as cell survival ratio. A survival ratio <1.0 indicates cell loss. At concentrations from 0.1 to 1.0 mM vitamin C and pyruvate quench hydroxyl radicals in the DHR assay in absence of living matter. In the presence of 0.1- 0.3 mM vitamin C and pyruvate, ARPE-19 showed a reduced survival ratio (0.87 +/- 0.01 to 0.89 +/- 0.02 after 6 h) which was not the case at the higher concentrations between 1 and 3 mM. The exposure of ARPE-19 cells to hydroxyl radicals reduced the survival ratio to 0.92 +/- 0.02. At concentrations at which vitamin C and pyruvate exert toxic effects, a potentiation of radical induced cell death can be observed (survival ratio 0.79 +/- 0.02 and 0.82 +/- 0.03, respectively). Higher concentrations of vitamin C or pyruvate had no explicit protective effect to the hydroxyl radical induced damage. Although vitamin C and pyruvate are potent hydroxyl radical quenchers in vitro they failed to protect cultured ARPE-19 cells from oxidative stress induced cell death. In contrast, when applying the scavengers at low concentrations a potentiation of cell damage was observed.

Lipid Changes During Storage of Milled Hulless Barley Products

Cereal Chem. 83(4):424–427 Waxy hulless barley is being utilized as a food ingredient because of its naturally elevated levels of soluble fiber (β-glucan). This soluble fiber reduces lipids in mildly hypercholesterolemic men and women (Behall et al 2004). In developing foods that contain barley, the stability of the raw material during storage is important and little is known about the storage stability of barley that has been processed into flours or steam-rolled flakes. Flavor deterioration in cereal grain flours and flakes during storage is mostly caused by lipid oxidation, although other proces-ses such as reactions of phenolics should also be included. There are two types of reactions of lipids that contribute to lipid degra-dation and, ultimately, to off-flavors and odors. These reactions are hydrolytic degradation of the triacylglycerides (TG) and phos-pholipids (PhL) due to activity of lipase with the release of free fatty acids and the following oxidation of released polyunsaturated fatty acids (PUFA). Free fatty acids impart a bitter flavor to foods, while products of oxidation are the substances that are responsible for rancidity. Barley contains 2–4% lipid (Morrison 1993). A majority of the lipid is unsaturated fatty acids (Palmer 1989) of which ≈57% is linoleic acid and 5% is linolenic acid (Morrison 1978). PUFA readily undergo oxidation, both enzymatic and nonenzymatic, pro-ducing lipid peroxides that decompose, producing aldehydes, ke-tones, and alcohols. Many of these secondary products of oxida-tion are volatile and responsible for undesirable odors while others undergo reactions producing compounds with undesirable flavor. The hydroperoxides formed from linoleic acid, the major PUFA found in barley, decompose rapidly, producing many products that have rancid flavors. Two enzymes play a role in the deterioration of lipids: lipase and peroxidase. Lipases release free fatty acids from TG and PhL, while peroxidases are responsible for the conversion of PUFA to lipid peroxides. Lipases can be inactivated by heat treatment but in oats this inactivation induces nonenzymatic oxidation (Lehtinen et al 2003). The degradation of the peroxides leading to the unde-sirable odors and flavors is proceeded by a free radical mech-anism. Barley contains high concentrations of vitamin E (Peterson and Qureshi 1993), a free radical scavenger that will reduce the formation of undesirable odors and flavors resulting from the degradation of peroxides. As a relatively new product, little information is available on the storage characteristics of processed barley. This study was initiated to monitor lipid degradation in milled barley flours and a steam-rolled barley flake under both accelerated and standard conditions.

Present knowledge and unexpected behaviours of vitamins A and E in colostrum and milk

Vitamins A and E are fat-soluble nutrients that exert various important roles especially during the early stages of life. Vitamin E is required to protect the newborn against oxidative stress and vitamin A is fundamental for growth and development. Both nutrients are also essential to ensure a good functioning of the immune system of the young. For these reasons and because of their limited placental transfer, vitamins A and E must be provided to the neonates in adequate amounts, in order to avoid a deficiency and maximize their disease resistance. Colostrum contains very high concentrations of vitamins A and E as compared to mature milk. The transfer of both nutrients into the milk does not seem to occur through a passive mechanism following the transfer of lipids. Supplementing gestating and lactating mothers appears to improve vitamin E levels in the milk and in the serum of neonates. The same phenomenon is also observed for milk vitamin A levels. However, the effect on the young seems to be less obvious. Even if much remains to be done concerning the metabolism of vitamins A and E during lactation, studies using seals as models have brought light on several important aspects of the transfer of vitamins A and E from mother to offspring.

The antioxidant and phylloquinone content of wildly grown greens in Crete

The traditional Mediterranean diet of Crete is renowned for its very high consumption of olive oil, vegetables, legumes, fruit, fish, whole-wheat cereals and a moderate consumption of dairy products and meat. Wild greens play an important role in the traditional diet and are eaten either fresh in salads, boiled or cooked in pies, thus increasing the daily vitamin and antioxidant intake of the population that adheres to the traditional diet. Six cultivated and 48 wildly grown greens were collected and analyzed for their carotenoid, l-ascorbic acid, phylloquinone, γ-tocopherol, α-tocopherol and total polyphenol content. In most cases, the wild greens had higher micronutrient contents than those cultivated. Certain wild greens, such as Rumex obtusifolius, Prasium majus and Lathyrus ochrus had higher concentrations of vitamin K 1, vitamin C, lutein, β-carotene, γ-tocopherol and total polyphenol content than those cultivated; proving the significance of these wildly grown greens for the well being of the Cretan population.

Lipid-soluble and water-soluble antioxidant activities of the avian intestinal mucosa at different sites along the intestinal tract

The antioxidant capacity of the avian intestinal mucosa is potentially important in protecting the gut wall from the harmful actions of reactive oxygen species originating from the diet, mucosal metabolism and the inflammatory response to enteric microbes. To assess this capacity, we determined the total lipid-soluble and water-soluble antioxidant activities of mucosal extracts, using tissue from different parts of the intestinal tract of the chicken. The lipid-soluble antioxidants, vitamin E and carotenoids, were also measured in the same samples. Total lipid-soluble antioxidant activity was highest in mucosa from the duodenum followed by the jejunum, with much lower activities in the ileum, ceca and colon. Total water-soluble antioxidant activity of the mucosa was at least an order of magnitude greater than the lipid-soluble activity under the assay conditions and did not differ significantly among the different parts of the intestinal tract. High concentrations of vitamin E were present in the mucosa of the duodenum and jejunum, with a trend to lower levels in the ileum and ceca, and significantly less in the colon. Similarly, the mucosa of the duodenum and jejunum contained the highest concentrations of carotenoids, with much lower levels in the ileum and colon. The different isoforms of vitamin E were absorbed from the digesta by the mucosa without any major selectivity. However, the liver was greatly enriched with α-tocopherol over the other isoforms, indicating a high degree of discrimination by this tissue. The results indicate major differences in the relative contributions of lipid- and water-soluble antioxidants in the mucosa along the different parts of the intestinal tract, most likely reflecting the sites of vitamin E and carotenoid absorption.

Inhibitory effects of riboflavin (Vitamin B 2) on the in vitro rooting and nutrient concentration of explants of peach rootstock GF 677 ( Prunus amygdalus × P. persica)

The effect of vitamin riboflavin (B 2) on in vitro rooting of the almond × peach hybrid clone GF 667 was studied. Riboflavin was added in five concentrations: 0 (control), 0.5, 1.0, 1.5 and 2.0 mg l −1. After 4 weeks in culture, riboflavin did not stimulate adventitious rooting of the explants and rooting was very low in comparison to the control treatment. A high percentage of shoots on the rooting media containing the two highest concentrations of Vitamin B 2 had shown symptoms of chlorosis and apex necrosis.

Hematological, Metabolic, and Endocrine Effects of Feeding Vitamin A and Lactoferrin in Neonatal Calves

There are reports of important interactions among vitamin A, lactoferrin (Lf), and components of the insulin-like growth factor (IGF) system. Newborn calves are deficient in vitamin A and have a low Lf status. Colostrum contains vitamin A, Lf, and members of the IGF system, including IGF binding proteins (IGFBP), and these compounds may exert mutual interactions in neonatal calves. Effects of feeding different amounts of vitamin A and Lf on hematological, metabolic, and endocrine traits during the first 5 d of life were studied in neonatal calves. Calves were fed a milk-based formula without (F) or with added vitamin A [FA; 351, 402, 490, and 490μmol/kg dry matter (DM) on d 1, 2, 3, and 4, respectively], Lf (FL; 3850, 1990, 660, and 660 mg/kg DM on d 1, 2, 3, and 4, respectively), or vitamin A + Lf (FAL) and colostrum (C). Blood samples were taken preprandially on d 1 to 5 and postprandially on d 1, 2, and 4 for the study of hematological, metabolic, and endocrine traits. As intestinal absorption of Lf in formula-fed calves was obviously lower than in colostrum-fed calves, Lf supplementation did not influence the metabolic and endocrine status. Plasma vitamin A concentrations increased from d 1 to 5 in FA, FAL, and C, but remained low in F and FL. Addition of vitamin A to F affected concentrations of vitamin A from d 2 to 5; hemoglobin and triglycerides on d 3; and tended to influence IGFBP-3 levels on d 5. On d 1, preprandial insulin concentrations in F and FL were higher than those in FA and FAL and growth hormone concentrations on d 3 in FA were higher than in FAL. In C, plasma Lf concentrations increased on d 1 and then decreased until d 5, whereas plasma urea and IGF-I concentrations remained stable. Compared with F-fed calves, C-fed calves had higher plasma concentrations of Lf from d 1 to 4, higher concentrations of vitamin A on d 5, higher concentrations of total protein from d 2 to 5, higher concentrations of triglycerides on d 3 and 4, and higher concentrations of IGF-I on d 4 and 5, but lower urea concentrations on d 4 and 5 and lower basal growth hormone concentrations than in F, FL, and FA. In conclusion, metabolite and hormone concentrations were influenced by differences in feeding. Addition of vitamin A influenced concentrations of vitamin A, hemoglobin, and triglycerides and tended to affect IGFBP-3 levels. Lactoferrin and vitamin A did not interact with respect to the IGF-I and IGFBP-3 status.

Vitamin C transiently arrests cancer cell cycle progression in S phase and G2/M boundary by modulating the kinetics of activation and the subcellular localization of Cdc25C phosphatase

Regulation of cell cycle progression involves redox (oxidation-reduction)-dependent modification of proteins including the mitosis-inducing phosphatase Cdc25C. The role of vitamin C (ascorbic acid, ASC), a known modulator of the cellular redox status, in regulating mitotic entry was investigated in this study. We demonstrated that vitamin C inhibits DNA synthesis in HeLa cells and, mainly the form of dehydroascorbic acid (DHA), delays the entry of p53-deficient synchronized HeLa and T98G cancer cells into mitosis. High concentrations of Vitamin C caused transient S and G2 arrest in both cell lines by delaying the activation of the M-phase promoting factor (MPF), Cdc2/cyclin-B complex. Although vitamin C did not inhibit the accumulation of cyclin-B1, it may have increased the level of Cdc2 inhibitory phosphorylation. This was achieved by transiently maintaining Cdc25C, the activator of Cdc2, both in low levels and in a phosphorylated on Ser216 inactive form that binds to 14-3-3 proteins contributing thus to the nuclear exclusion of Cdc25C. As expected, vitamin C prevented the nuclear accumulation of Cdc25C in both cell lines. In conclusion, it seems that vitamin C induces transient cell cycle arrest, at least in part, by delaying the accumulation and the activation of Cdc25C.

Cashew (Anacardium occidentale) apple juice lowers mutagenicity of aflatoxin B1 in S. typhimurium TA102

Cashew (Anacardium occidentale) is a medicinal plant native to Brazil and also yields a nutritious fruit juice. Its large pulpy pseudo-fruit, referred to as the cashew apple, contains high concentrations of vitamin C, carotenoids, phenolic compounds and minerals. Natural and processed cashew apple juice (CAJ/cajuina) are amongst the most popular juices in Brazil, especially in the north-east. Both juices have antioxidant potential and suppress mutagenicity of hydrogen peroxide. In the present study we evaluated the inhibitory effects of CAJ/cajuina on Aflatoxin B1(AFB1)-induced mutation, using the Salmonella/microsome assay with the experimental approaches of pre-, co- and post-treatments. Both CAJ/cajuina suppress AFB1-induced mutagenesis in strain TA102 when applied in co- and in post-treatment. Possible mechanisms for anti-mutagenicity in co-treatment are (a) interaction with S9 enzymes, (b) metabolization to non-mutagenic compounds of AFB1 or (c) inactivation of S9 potential. Total suppression of AFB1 mutagenicity was observed in co-treatment with both CAJ and cajuina. Post-treatment anti-mutagenicity of both juices suggests a modulation of activity of error-prone DNA repair. CAJ/cajuina may be considered promising candidates for control of genotoxicity of AFB1 and may thus be considered as health foods with anti-carcinogenic potential. This promising characteristic warrants further evaluation with in vivo studies.

Vitamin C in breast milk may reduce the risk of atopy in the infant.

To assess the effects of maternal dietary and supplement intake of vitamins C and E on breast milk antioxidant composition (vitamin C, alpha-tocopherol and beta-carotene) and their protective potential against the development of atopy in the infant. Mothers with atopic disease were recruited at the end of gestation and maternal sensitization was assessed by skin-prick testing. The 4-day food records of the mothers and breast milk samples were collected at the infants' age of 1 month. Infants' atopy was defined by the presence of atopic dermatitis during the first year of life and a positive skin-prick test reaction at 12 months of age (n=34). Maternal intake of vitamin C in diet but not as supplement was shown to determine the concentration of vitamin C in breast milk. A higher concentration of vitamin C in breast milk was associated with a reduced risk of atopy in the infant (OR=0.30; 95% CI 0.09-0.94; P=0.038), whereas alpha-tocopherol had no consistent relationship with atopy. The group at risk of suboptimal vitamin C supply from breast milk was identified as infants whose mothers suffer from food hypersensitivity. A maternal diet rich in natural sources of vitamin C during breastfeeding could reduce the risk of atopy in high-risk infants.

Effets des nutriments sur les structures et les fonctions du cerveau : le point sur la diététique du cerveau

The brain is an organ elaborated and functioning from substances present in the diet. Dietary regulation of blood glucose level (via ingestion of food with a low glycemic index ensuring a low insulin level) improves the quality and duration of intellectual performance, if only because at rest the adult brain consumes 50 p. 100 of dietary carbohydrates, 80 p. 100 of them for energy purposes. The nature of the amino acid composition of dietary proteins contributes to good cerebral function; tryptophan plays a special role. Many indispensable amino acids present in dietary proteins help to elaborate neurotransmitters and neuromodulators. Omega-3 fatty acids provided the first coherent experimental demonstration of the effect of dietary nutrients on the structure and function of the brain. First it was shown that the differentiation and functioning of cultured brain cells requires omega-3 fatty acids. It was then demonstrated that alpha-linolenic acid (ALA) deficiency alters the course of brain development, perturbs the composition and physicochemical properties of brain cell membranes, neurones, oligodendrocytes, and astrocytes (ALA). This leads to physicochemical modifications, induces biochemical and physiological perturbations, and results in neurosensory and behavioral upset. Consequently, the nature of polyunsaturated fatty acids (in particular omega-3) present in formula milks for infants (premature and term) conditions the visual and cerebral abilities, including intellectual abilities. Moreover, dietary omega-3 fatty acids are certainly involved in the prevention of some aspects of cardiovascular disease (including at the level of cerebral vascularization), and in some neuropsychiatric disorders, particularly depression, as well as in dementia, notably Alzheimer's disease. Their deficiency can prevent the satisfactory renewal of membranes and thus accelerate cerebral aging. Iron is necessary to ensure oxygenation, to produce energy in the cerebral parenchyma, and for the synthesis of neurotransmitters. The iodine provided by the thyroid hormone ensures the energy metabolism of the cerebral cells. The absence of iodine during pregnancy induces severe cerebral dysfunction, leading to cretinism. Manganese, copper, and zinc participate in enzymatic mechanisms that protect against free radicals, toxic derivatives of oxygen. The use of glucose by nervous tissue implies the presence of vitamin B1. Vitamin B9 preserves memory during aging, and with vitamin B12 delays the onset of signs of dementia, provided it is administered in a precise clinical window, at the onset of the first symptoms. Vitamins B6 and B12, among others, are directly involved in the synthesis of neurotransmitters. Nerve endings contain the highest concentrations of vitamin C in the human body. Among various vitamin E components, only alpha-tocopherol is involved in nervous membranes. The objective of this update is to give an overview of the effects of dietary nutrients on the structure and certain functions of the brain.

Vitamins A and D but not E and K decreased the cell number in human pancreatic cancer cell lines

Background: The four fat‐soluble vitamins A, D, E and K have been tested in experimental and human studies to assess their influence on the growth of cancer cells of different origins. Receptors for vitamin A and D have been detected on pancreatic cancer cells, and analogues of these reduced the cell number in vitro. The aim of the present study was to evaluate the effect of fat‐soluble vitamins on the growth of pancreatic cancer cells. Methods: The seven cell lines used were established from patients operated on for pancreatic adenocarcinoma. The effect of incubation with the vitamin A analogues all‐trans‐retinoic acid (atRA;tretinoin) and 9‐cis‐retinoic acid (9‐cis‐RA), the synthetic vitamin D analogue EB 1089, vitamin E succinate and K1on the cell number was examined by the XTT method. Results: The vitamin A and D analogues decreased the pancreatic cancer cell number when high concentrations of 10−5– 10−4M were administered. A combination of retinoids and the vitamin D analogue EB 1089 did not enhance the effect. Vitamin E succinate inhibited cell growth to a small extent (maximal 26%) in 3 out of 7 cell lines, whereas vitamin K1increased the pancreatic cancer cell number in 3 out of 7 cell lines. Conclusion: High concentrations of vitamin A and D analogues decreased the cell number in pancreatic cancer cell lines. Vitamin E succinate and K1did not have this effect. In the treatment of pancreatic cancer, further exploration of vitamin D analogues could be fruitful.