Reduction In Vitamin Research Articles

Seasonal reduction in vitamin D level persists into spring in NSW Australia: implications for monitoring and replacement therapy

Seasonal variation in 25-hydroxyvitamin D [25OHD] status and its relationship to gender, age, socioeconomic and geographic determinants in Australians has not been described in large biomedical sampling cohorts. To analyse 25OHD levels in all primary tests undertaken consecutively in a 2-year period to determine the prevalence of 25OHD deficiency and its relation to patient setting, gender, age, season, urban or rural residency, socioeconomic status, latitude and longitude. We assessed 24 819 ambulatory and inpatient samples taken from the largest reference laboratory in NSW, Australia between 01 July 2008 and 30 July 2010. Serum 25OHD was measured using chemiluminescent immunoassay. Vitamin D deficiency was defined as 25OHD <50 nm. Median 25OHD was 54 nm ranging from 63 nm in summer to 44 nm in spring and was lowest in inpatient women (49 nm) and highest in ambulatory men (64 nm). Mean 25OHD peaked in January (67 nm) and reached a nadir in August/September (39 nm). During summer, 36% subjects overall had a level below 50 nm, increasing to 58% in spring. The highest prevalence of deficiency occurred in female inpatients (42% in summer and 62% in spring). Factors associated with lower 25OHD included being tested in spring, an inpatient, female, aged 20-39 or >79 years, socioeconomically disadvantaged and from a major city. This cross-sectional study demonstrates the extent and duration of 25OHD deficiency is greater than expected, and particular individuals are at higher risk. Our findings imply that supplementation guidelines need to be modified and strengthened.

Antioxidant Metabolism during Fruit Development of Different Acerola (Malpighia emarginata D.C) Clones

The present research work describes the major changes in the antioxidant properties during development of acerola from five different clones. Ripening improved fruit physicochemical quality parameters; however, total vitamin C and total soluble phenols (TSP) contents declined during development, which resulted in a lower total antioxidant activity (TAA). Despite the decline in TSP, at ripening, the anthocyanin and yellow flavonoid content increased and was mainly constituted of cyanidin 3-rhamnoside and quercetin 3-rhamnoside, respectively. The activities of oxygen-scavenging enzymes also decreased with ripening; furthermore, the reduction in vitamin C was inversely correlated to membrane lipid peroxidation, indicating that acerola ripening is characterized by a progressive oxidative stress. Among the studied clones, II47/1, BRS 237, and BRS 236 presented outstanding results for vitamin C, phenols, and antioxidant enzyme activity. If antioxidants were to be used in the food supplement industry, immature green would be the most suitable harvest stage; for the consumer's market, fruit should be eaten ripe.

Interference with RhoA–ROCK Signaling Mechanism in Autoreactive CD4+ T Cells Enhances the Bioavailability of 1,25-Dihydroxyvitamin D3 in Experimental Autoimmune Encephalomyelitis

Vitamin D deficiency is a major risk factor for central nervous system (CNS) demyelinating diseases including multiple sclerosis (MS) and its animal model, that of experimental autoimmune encephalomyelitis (EAE). Both vitamin D(3) and 1, 25-dihydroxyviatmin-D(3) (calcitriol) had beneficial effects in EAE/MS. However, the exact cause of vitamin D deficiency in EAE/MS is not clear. Previously, we documented that lovastatin (LOV) provides protection in EAE animals via inhibition of RhoA-ROCK signaling. Herein, we demonstrate that LOV prevents the lowering of circulating 25-hydroxyvitamin-D(3) and 1,25-dihydroxyviatmin-D(3) levels including 1,25-dihydroxyviatmin-D(3) levels in the peripheral lymphoid organs and CNS of treated EAE animals. These effects of LOV were attributed to enhanced expression of vitamin D synthesizing enzyme (1α-hydroxylase) in kidney and the CNS, with corresponding reduction of vitamin D catabolizing enzyme (24-hydorxylase) expression in the CNS of EAE animals via inhibition of RhoA-ROCK signaling. Ex vivo and in vitro studies established that autoreactive Th1/Th17 cells had higher expression of 24-hydroxylase than Th2/T regulatory cells, that was reverted by LOV or ROCK inhibitor. Interestingly, LOV-mediated regulation of vitamin D metabolism had improved vitamin D(3) efficacy to confer protection in EAE animals and that was ascribed to the LOV- and calcitriol-induced immunomodulatory synergy. Together, these data provide evidence that interfering with RhoA-ROCK signaling in autoreactive Th1/Th17 cells can improve vitamin D(3) efficacy in clinical trials of MS and related neurodegenerative disorders.

The inhibitory effect of dietary fructose on lactation‐induced increases in rat epithelial calcium transport is mediated by fructose‐induced reductions in vitamin D levels

Pregnancy and lactation require marked increases in consumption and transport of dietary Ca2+ to maintain Ca2+ homeostasis and bone health. This increase in epithelial Ca2+ transport is regulated by increasing levels of calcitriol whose genomic effects are mediated by the vitamin D receptor (VDR). We recently showed that fructose (F) consumption reduced intestinal Ca2+ transport. We used lactating rats as animal model to test whether the deleterious effects of excessive F intake on Ca2+ transport is regulated by calcitriol and lead to bone defects. Pregnant and virgin (control) rats were fed isocaloric 63% F or, as controls, glucose and starch diets from d 2 of gestation to end of lactation. Compared to virgins, lactating dams fed glucose or starch had higher rates of intestinal Ca2+ transport, elevated intestinal and renal expression of Ca2+ transporters, as well as increased levels of calcitriol and 1‐alpha‐hydroxylase. F consumption prevented these lactation‐induced increases, and reduced VDR binding to promoter regions of TRPV6 and CaBP9k. Bone mineral density, content and mechanical strength each decreased with lactation, and this decrease was exacerbated by F diet. In lactating rats with enhanced Ca2+ needs, excessive F intake prevents, through a calcitriol‐dependent pathway, adaptive increases in epithelial Ca2+ transport, likely compromising bone quality (NSF IOS‐1121049, Benjamin Delessert)

Side-chain selenium-containing amphiphilic block copolymers: redox-controlled self-assembly and disassembly

In this paper we report the synthesis and study of a series of side-chain selenium-containing amphiphilic poly(ethylene oxide-b-acrylic acid) block copolymers PEO-b-PAA-Se. These block copolymers can self-assemble in aqueous solution and form spherical micellar aggregates. The selenide group of PEO-b-PAA-Se can change into hydrophilic selenoxide under mild oxidation of 0.1% hydrogen peroxide, leading to the disassembly of the spherical micellar aggregates. Small compounds like Nile Red can be encapsulated into the micellar aggregates and show fast release upon the addition of 0.1% hydrogen peroxide. More interestingly, the oxidation state of selenoxide can be reversed to selenide under reduction of Vitamin C, thus recovering the spherical aggregates. The reversible oxidation and reduction process shows good reversibility and can be repeated at least 7 times. It is hoped that this reversible redox controlled system may function as nanocontainers for potential application in the areas such as responsive drug delivery and anti-oxidation studies.

Disruption of non-enzymatic antioxidant defense systems in the brain of rats with water-immersion restraint stress

We examined whether non-enzymatic antioxidant defense systems are disrupted in the brain of rats with water-immersion restraint stress. When rats were exposed to water-immersion restraint stress for 1.5, 3 or 6 h, the brain had decreased ascorbic acid and reduced glutathione contents and increased lipid peroxide and nitric oxide metabolites contents at 3 h and showed further changes in these components with a reduction of vitamin E content at 6 h. Increased serum levels of stress markers were found at 1.5, 3 or 6 h of WIRS. Oral pre-administration of L-ascorbic acid (1.5 mmol/kg) or vitamin E (0.5 mmol/kg) to rats with 6 h of water-immersion restraint stress attenuated the increases in lipid peroxide and nitric oxide metabolites contents and the decrease in vitamin E content in the brain. Pre-administered L-ascorbic acid attenuated the decreases in brain ascorbic acid and reduced glutathione contents at 6 h of water-immersion restraint stress, while pre-administered vitamin E enhanced the decreases in those contents. Pre-administered L-ascorbic acid or vitamin E did not affect the increased serum levels of stress markers in rats with 6 h of water-immersion restraint stress. These results indicate that water-immersion restraint stress causes disruption of non-enzymatic antioxidant defense systems through enhanced lipid peroxidation and nitric oxide generation in the brain of rats with water-immersion restraint stress.

Re Yu et al. The natural history of treated and untreated primary hyperparathyroidism: the Parathyroid Epidemiology and Audit Research Study. Q J Med 2011; 104:513-521

Sir, This interesting study reports that many people with ‘mild untreated’ primary hyperparathyroidism (PHPT) do not progress to require parathyroidectomy during an average of 4.7 years of follow-up.1 The authors also report decreases in serum calcium during follow-up of up to 12 years in this cohort despite concomitant increases in serum parathyroid hormone concentrations. Though the authors consider it unlikely, these paradoxical findings might reflect reductions in vitamin D status due to …

Chemical and physicochemical characteristics changes during passion fruit juice processing

Passion fruit is widely consumed due to its pleasant flavour and aroma acidity, and it is considered very important a source of minerals and vitamins. It is used in many products such as ice-cream, mousses and, especially, juices. However, the processing of passion fruit juice may modify the composition and biodisponibility of the bioactive compounds. Investigations of the effects of processing on nutritional components in tropical juices are scarce. Frequently, only losses of vitamin C are evaluated. The objective of this paper is to investigate how some operations of passion fruit juice processing (formulation/homogeneization/thermal treatment) affect this product's chemical and physicochemical characteristics. The results showed that the chemical and physicochemical characteristics are little affected by the processing although a reduction in vitamin C contents and anthocyanin, large quantities of carotenoids was verified even after the pasteurization stage.

Light and Moderate Doses of Ethanol in Chemical Carcinogenesis of the Colon in Rats

The aberrant crypt foci (ACF), cyclooxygenase 2 (COX-2), and the proliferating cell nuclear antigen (PCNA) are putative biomarkers for colon cancer. To study the association between light (1 g of ethanol/kg bw) and moderate (3 g of ethanol/kg bw) doses of ethanol with the chemical carcinogen N-methyl-N′-nitro-N-nitrosoguanidine (MNNG), Wistar rats were divided into 6 groups. The colon fragments were collected for histochemical and immunohistochemical analyses, and the liver samples were collected for oxidative stress analysis, with products of lipid peroxidation (malondialdehyde), antioxidant enzymes (glutathione), and vitamin E. The association of light and moderate doses of ethanol with MNNG did not present differences in the oxidative parameters. However, a reduction in vitamin E levels in the carcinogen groups was observed. The association induced a reduction of the COX-2 and PCNA expression. The number of ACF in the group that received a light dose of ethanol had lower rates, while the group that received a moderate dose had the highest rates compared to the control MNNG, demonstrating that the light dose of ethanol could have a protective effect, while the moderate dose could represent a risk during chemical carcinogenesis in rats.

Visual impairment in children in middle- and lower‑income countries

Reducing visual impairment and blindness in children in resource-poor countries is one of the key components of the major global prevention of blindness initiative, VISION 2020 the Right to Sight....

Does online hemodiafiltration lead to reduction in trace elements and vitamins?

Hemodiafiltration (HDF) has been reported to improve nutritional intake, but as it increases convective losses, it could also increase micronutrient loss. We prospectively audited the effect of HDF on vitamin B12, zinc and selenium. Thirty-four patients dialyzing (T/Th/Sa) switched to HDF, and 44 dialyzing (M/W/F) remained on high-flux hemodialysis (HD) and were followed for 12 months. Dialysis adequacy, weight, hemoglobin, and serum albumin did not differ between the groups and did not change over 12 months' follow up. Similarly, vitamin B12 did not differ: HDF, 443 (325-682) ng/mL HD vs. 478 (327-690) ng/mL HDF; 6 months, 513 (351-664) ng/mL vs. 460 (379-647) ng/mL; or 12 months, 444 (317-617) ng/mL vs. 492 (323-644) ng/mL. And no patient had subnormal values. Folate levels, in those not taking supplements, were also stable (start, 6.2 ± 0.7 μg/L HD vs. 7.2 ± 1.0 μg/L HDF; 12 months, 6.5 ± 0.9 μg/L vs. 10.9 ± 2.4 μg/L). Serum zinc was subnormal in 50% prior to switching to HDF, 10.4 ± 0.4 μmol/L, but did not fall with HDF 10.2 ± 0.3 μmol/L; similarly, selenium was low in 49% prior to switching to HDF, 0.77 ± 0.06 μmol/L, but remained stable on HDF, 0.82 ± 0.06 μmol/L. Although HDF adds convective clearance to standard hemodialysis, it does not lead to a reduction in vitamin B12, folate, zinc, or selenium. However, half of this dialysis cohort had low levels of both zinc and selenium.

SP6-49 Evaluation of the deficiency of vitamin D in a population of women in Brazil: pilot study

IntroductionVitamin D serum dosage evaluation in 40 women submitted to the WHO Healthy Life Quality—SHORT FORM 36 (SF-36).MethodsCross-sectional, random study of 40 patients in a private practice, submitted to the...

Reduction of vitamin A deficiency and anemia in pregnancy after implementing proposed prenatal nutritional assistance.

Micronutrient deficiency is an unquestionable public health problem, specially anemia and vitamin A deficiency (VAD). This is due to the collective dimension of these carencies, which reflects on morbimortality rates in the maternal and infant group. to evaluate the impact of a proposal for prenatal nutritional assistance, comparing the prevalence of anemia and VAD, in pre-intervention (GI) and intervention (GII) groups. this is a prospective intervention study in a cohort of pregnant women. The GI group was made up of 225 the GII group of 208 pregnant adults and their respective newborns, attended a Public Maternity Ward in Rio de Janeiro, Brazil. Concentration of hemoglobin was used to diagnose anemia and a standardized interview to diagnose night blindness (XN). after adjusting for confounding variables, through logistic regression, the protective effect of intervention at the onset of anemia (OR = 0.420; IC 95% = 0.251-0.702), with a significant reduction in prevalence, of 28.4% in the GI to 16.8% in the GII, also observed at the onset of XN (OR = 0.377; IC95% = 0.187- 0.759), with a reduction in prevalence of 18.7 % in the GI to 6.2% in the GII. Nutritional intervention has a beneficial effect on maternal health, reducing nutritional deficiencies most prevalent during pregnancy and the impact of these on the obstetric ailment.

Indirect inhibition of vitamin K epoxide reduction by salicylate.

Salicylate antagonizes the vitamin K-dependent biosynthesis of clotting factors in the rat and produces an elevation of the ratio of vitamin K epoxide to vitamin K in the liver. Vitamin K epoxide is reduced to vitamin K by a vitamin K epoxide reductase, and 1 mM salicylate was required to cause a 50% inhibition of the dithiothreitol-dependent in-vitro reduction of vitamin K epoxide by this enzyme. This enzyme was, however, inhibited 50% by as little as 70-80 microM salicylate when reducing equivalents for the reaction were furnished by endogenous cytosolic reductants. This effect on the cytosolic reductant supply was shown to be unrelated to a previously demonstrated inhibition of DT-diaphorase by salicylate. The concentrations of salicylate at which significant inhibitory effects are exerted in-vitro (50-100 microM) are below the 200 microM levels observed in the livers of rats given an anticoagulating dose of salicylate.

A hetero-dimer model for concerted action of vitamin K carboxylase and vitamin K reductase in vitamin K cycle

Vitamin K carboxylase (VKC) is believed to convert vitamin K, in the vitamin K cycle, to an alkoxide–epoxide form which then reacts with CO 2 and glutamate to generate γ-carboxyglutamic acid (Gla). Subsequently, vitamin K epoxide reductase (VKOR) is thought to convert the alkoxide–epoxide to a hydroquinone form. By recycling vitamin K, the two integral-membrane proteins, VKC and VKOR, maintain vitamin K levels and sustain the blood coagulation cascade. Unfortunately, NMR or X-ray crystal structures of the two proteins have not been characterized. Thus, our understanding of the vitamin K cycle is only partial at the molecular level. In this study, based on prior biochemical experiments on VKC and VKOR, we propose a hetero-dimeric form of VKC and VKOR that may explain the efficient oxidation and reduction of vitamin K during the vitamin K cycle.

Variation in Content of Carotenoids and Vitamin C in Carrots

Carrots are the most popular and wide-spread of all root vegetables, and are the principal source of carotenoids in human diet. The purpose of this study was to examine differences between cultivars and the effect of storage regarding the carotenoid and vitamin C content in carrots. Six carrot cultivars were used in this study, ranging from early to late ones. Observed carotenoid content ranged from 60 mg kg-1 to 134 mg kg-1. Significantly higher levels of carotenoids were found in late and moderately late cultivars in comparison to early ones. Vitamin C content in these cultivars ranged from 54 mg kg-1 to 132 mg kg-1. Significantly higher contents of vitamin C were also found in the late cultivars. 30-day storage resulted in a significant reduction in vitamin C content, on average of 47%. There was also a reduction in the carotenoids content, but to a lesser extent, on average of 11%.

Ozone-induced changes of antioxidant capacity of fresh-cut tropical fruits

Abstract The effect of ozone treatment on total phenol, flavonoid, and vitamin C content of fresh-cut honey pineapple, banana ‘pisang mas’, and guava was investigated. The fresh-cut fruits were exposed to ozone at a flow rate of 8 ± 0.2 ml/s for 0, 10, 20, and 30 min. The antioxidant capacity of the fruits was evaluated by measuring the ferric reducing/antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging activity. Total phenol and flavonoid contents of pineapple and banana increased significantly when exposed to ozone for up to 20 min, with a concomitant increase in FRAP and DPPH values. The opposite was observed for guava. Ozone treatment significantly decreased the vitamin C content of all three fruits. The study shows promising results for enhancing antioxidant capacity of some fresh fruits by ozone treatment although the positive effect is compromised by a reduction in vitamin C content. Industrial relevance The preservation of antioxidant properties, storage stability and safety is of utmost importance in the minimally processed fresh food industry. Ozone has been looked into as an alternative sanitizing technology in the fresh produce industry. The results of this study indicate that ozone can be used in the minimally processed fresh food industry to enhance the antioxidant status of fresh-cut fruits.

Antioxidant contents of pre‐packed fresh‐cut versus whole fruit and vegetables

PurposeThe purpose of this paper is to evaluate the difference in antioxidant contents of pre‐packed fresh‐cut and whole fruit and vegetables as sold in the market.Design/methodology/approachSamples of pre‐packed fresh‐cut fruit and vegetables as well as whole produce were collected from the market in Muscat and Oman, and analyzed for vitamin C, lycopene and total carotenoids. Analysis of variance was carried out to determine the level of statistical differences between fresh‐cut and whole fruit and vegetables.FindingsIn both fruit and vegetables, vitamin C contents are higher in whole than fresh‐cut produce, with greater reductions in vitamin C contents of fresh‐cut vegetables than fruit. In both fresh‐cut and whole fruit, lycopene content is 30‐36 times higher in watermelon than the contents of other fruit genotypes studied. Similarly, total carotenoids content of watermelon is six to 21 times higher than other types of fruit studied. Both lycopene and total carotenoids content are higher in whole than fresh‐cut fruit, except in pineapple fruit. In both fresh‐cut and whole vegetables, lycopene content of carrot is three to four times higher than cucumber, and four to six times higher than celery. Implications of these results on public health policy are discussed.Originality/valuePrevious studies on quality of fresh‐cut produce are based on controlled experimental studies using samples of produce from the same batch to compare fresh‐cut versus whole produce. However, consumers in retails stores often have to make a choice between pre‐packed fresh‐cut or whole (un‐cut) produce, which are not usually from the same source or batch. It is therefore essential to understand the differences in nutritional value of whole and pre‐packed fresh‐cuts sold in the market.

Modulation of fibrogenic factors in hepatic stellate cells by Vitamin D and reduction of Vitamin D in NAFLD patients: Implications for NAFLD therapy

Introduction: Non-alcoholic fatty liver disease (NAFLD) is the most common hepatopathy and is closely associated with metabolic abnormalities. Patients with advanced liver disease exhibit vitamin-D (VD) deficiency. Our aim was to assess if VD influences primary hepatic stellate cells (HSC) phenotype and function, and possibly modulates NASH-associated fibrogenesis.

Impact of NGO run mid day meal program on nutrition status and growth of primary school children

To study the impact of wholesome mid day meal (MDM) program run by an NGO on the growth of the primary school students in rural area of Mathura district. This intervention study involved children enrolled in Government run rural primary schools in Mathura district in Uttar Pradesh from March 06 through August 07. A wholesome, nutritionally balanced MDM provided by an NGO for the students in the 6 primary schools was selected as intervention group. Control group consisted of children in 8 schools which received locally prepared MDM by village panchayats. Height, weight, change in height/month, change in weight/month, prevalence of protein-energy malnutrition and prevalence of signs of vitamin deficiencies, were measured. Food was provided for 221 days in one year. Within group and between groups repetitive measures were compared using generalized estimating equation (GEE). Within both intervention and control groups height and weight had significantly increased (p < 0.05), while there was no significant difference between the groups. There was no change in prevalence of malnutrition within either of the groups. Reduction in vitamin A deficiency signs was 38% more in intervention group (p < 0.001). Prevalence of Vitamin D deficiency reduced by 50% more in intervention group. No such differences between groups were observed for vitamin B complex and vitamin C. MDM provided by the NGO has no better impact on growth of the primary school children, however, it reduced prevalence of vitamin deficiency significantly in comparison to the MDM run by Village Panchayats.