Basis Of Vitamin Research Articles

Vitamin D and breast cancer: Molecular communications

Epidemiological studies have demonstrated that vitamin D status is inversely associated with breast cancer incidence, mortality, and recurrences, suggesting vitamin D as a potent agent to reduce the risk of breast cancer. The hormonally active metabolite of vitamin D, 1α,25- dihydroxyvitamin D (1α,25(OH)2D, calcitriol), and its analogs have exerted inhibitory activity of cellular proliferation through arresting cell cycle and inducing apoptosis, and suppressive effects on the invasion, angiogenesis, and metastasis of breast cancer. In the studies of molecular basis of vitamin D activities, many upstream signaling pathways cross-talking with vitamin D signaling have been investigated. 1α,25(OH)2D and its analogs regulates different signaling pathways mediated by transforming growth factor-β superfamily, epidermal growth factor receptors family, estrogen signaling-related molecules, insulin-like growth factor-binding proteins, and protein kinase C. The multipotent activities of vitamin D in signaling modulation may be efficient and effective in suppressing highly heterogeneous breast cancer.

Vitamin D status may contribute to serum insulin-like growth factor I concentrations in healthy subjects.

The aim of the study was to evaluate whether vitamin D [25-(OH) D3] status affects serum IGFI concentrations in healthy subjects. Two hundred and forty-one consecutive healthy subjects were included in the present study. Serum IGF-I and 25-(OH) D3 concentrations. As expected, serum IGF-I concentrations progressively decreased with age (r=-0.55, p<0.0001); on the contrary, gender was not related to serum IGF-I levels. A positive relationship was identified between serum 25-(OH) D3 and IGF-I concentrations (r=0.33, p<0.0001); the 25-(OH) D3-dependent changes of serum IGF-I concentrations were observed also when subjects were divided on the basis of vitamin D deficiency; in fact, those with severe 25-(OH) D3 deficiency (<20 ng/ml) had lower (185 ± 83 μg/l) IGF-I values than those with mild-to absent 25-(OH) D3 deficit (225 ± 83 μg/l, p=0.0004). 25-(OH) D3 status may contribute to determine serum IGF-I levels in healthy population.

Vitamin D as Adjunctive Therapy in Refractory Pulmonary Tuberculosis: A Case Report

Vitamin D regulates calcium homeostasis in the body and may play a major role in regulating immune responses to tuberculosis (TB). Pilot studies suggest that vitamin D supplementation may improve outcomes in pulmonary TB (PTB), but clinical evidence using vitamin D in TB treatment is limited. We present a case of vitamin D deficiency in a woman with refractory drug-susceptible PTB. Antituberculous therapy and the correction of vitamin D deficiency resulted in clinical and microbiologic improvement at month 13 of her treatment. The basis for vitamin D/TB interactions and a brief literature review are discussed. Data from controlled trials are needed to evaluate the efficacy of vitamin D as adjunctive TB therapy.

Severe Vitamin D Deficiency in Arab-American Women Living in Dearborn, Michigan

To determine the prevalence and degree of 25-hydroxyvitamin D deficiency in a group of Arab-American women in the largest, most-concentrated Arab-American settlement in the United States and to search for correlations with dress, diet, and use of vitamin D-fortified foods and vitamin supplements. In this cross-sectional study, Arab-American women, 18 years and older, who attended an ethnic market on April 7 or 14, 2007, were recruited. Participants were interviewed by bilingual English- and Arabic-speaking investigators using a semi-structured interview to assess dress; demographic variables; medical history; medication use; clinical symptoms associated with vitamin D deficiency (eg, joint or bone pain, muscle weakness); and dietary intake of vitamin D from fortified orange juice, milk, and vitamin supplementation. Blood samples were drawn to measure concentrations of serum calcium, creatinine, phosphorus, alkaline phosphatase, parathyroid hormone, and 25-hydroxyvitamin D. Participants were initially divided into 2 groups based on whether the woman was veiled and further subdivided into 3 groups on the basis of vitamin D intake from supplemented food sources (milk or vitamin D-fortified orange juice) and vitamin pills: unveiled, veiled and taking supplements, and veiled and taking no supplements. Eighty-seven women participated. Serum 25-hydroxyvitamin D levels were uniformly low, with the highest levels in the unveiled group (median [interquartile range]) (8.5 ng/mL [5.75-13.5 ng/mL]) followed by the veiled, supplemented group (7 ng/mL [4-11.5 ng/mL]) and the veiled, unsupplemented group (4 ng/mL [2-6.8 ng/mL]). 25-Hydroxyvitamin D levels were lower in women with less experience in the United States and in those with less education. Vitamin D-fortified orange juice consumption had a greater positive predictive effect on serum 25-hydroxyvitamin D levels than either milk or vitamin pills and may possibly serve as a surrogate marker for vitamin D awareness. Vitamin D deficiency, as assessed by 25-hydroxyvitamin D concentrations, is endemic in a sample of Arab-American women living in Dearborn, Michigan. These findings potentially identify an important health problem in the largest, most-concentrated Arab-American population in the United States.

Effects of selenium supplementation as sodium selenite or selenized yeast and different amounts of vitamin E on selenium and vitamin E status of broilers

The aim of this experiment was to determine the effects of broiler meal supplementation with different forms of selenium (as Na-selenite or selenized yeast) and different amounts of vitamin E on selenium and vitamin E status in broiler tissues. A total number of 240 broilers (Cobb 500) were divided in four experimental groups supplemented with Se and vitamin E for a period of 42 days: group SS+E20 - 0.3 mg/kg sodium selenite and 20 IU of vitamin E; group SY+E20 - 0.3 mg/kg selenized yeast and 20 IU of vitamin E; group SS+E100 - 0.3 mg/kg sodium selenite and 100 IU of vitamin E; group SY+E100 - 0.3 mg/kg selenized yeast and 100 IU of vitamin E. Blood plasma Se and MDA concetrations and Se dependent GSH-Px were determined on days 1, 21 and 42, where's content of Se and vitamin E in breast muscle and liver were measured on days 21 and 42 of the experiment. Highest blood plasma glutathione peroxidase (GSH-Px) activities were detected in groups SS+E20 and SS+E100. Supplementation with selenium enriched yeast did not result in a significant increase in plasma GSH-Px activity. Selenium and vitamin E concentrations in breast meat and liver were significantly higher in groups supplemented selenized yeast compared to those receiving Na-selenite. Selenium and vitamin E supplementation did not alter plasma MDA concentrations, but in tissues, selenized yeast provided a consistent, although not significant, reduction in MDA content. The increased dose of vitamin E supplemented in broiler meal was not justifiable on the basis of vitamin E tissue content and antioxidative effect.

Effects of Different Drying Methods on the Quality Changes of Granular Edamame

In this article, the quality changes of the granular fruits and vegetables dried by vacuum microwave drying, freeze drying, hot air drying, and combined hot air–vacuum microwave drying are investigated, and the quality parameters compared on the basis of vitamin C and chlorophyll contents, shrinkage and rehydration capacity, color, texture, and microstructure changes. The quality parameters of products dried by vacuum microwave drying are slightly lower than those obtained by freeze drying, but much better than those obtained using conventional hot air drying. The quality characteristics of product dried by combined hot air–vacuum microwave are significantly improved compared to those simply hot air–dried.

Randomized, double-blind, placebo-controlled clinical trial of the efficacy of treatment with zinc or vitamin A in infants and young children with severe acute lower respiratory infection

Acute lower respiratory infection (ALRI) is a leading cause of childhood death. Zinc supplementation prevents ALRI. Vitamin A supplementation reduces childhood mortality, but its benefit concerning ALRI-specific mortality is unproven. The objective was to evaluate the effect of zinc and vitamin A on the clinical recovery of children with severe ALRI. In a controlled trial with a factorial design, 153 children aged 2-24 mo who were hospitalized with severe ALRI were randomly assigned to receive 10 mg zinc as acetate (twice daily for 5 d) plus vitamin A placebo, 10 000 micro g retinol equivalents vitamin A (twice daily for 4 d) plus zinc placebo, zinc plus vitamin A, or zinc and vitamin A placebos. The main outcome variable was the time for resolution of very ill status; other outcomes were resolution of fever, tachypnea, and feeding difficulty. Recovery rates from very ill status and from fever in zinc-treated boys were 2.6 times (P = 0.004) and 3 times (P = 0.003) those in non-zinc-treated children; feeding difficulty and tachypnea were not significantly different between groups after an adjusted analysis. Recovery rates were not significantly different between groups on the basis of vitamin A treatment. At discharge, serum zinc was 6.06 micro mol/L higher (P = 0.001) in the zinc-treated children, and serum retinol was 0.387 micro mol/L higher (P = 0.001) in the vitamin A-treated children. Zinc treatment significantly reduces duration of fever and very ill status in boys, but not in girls, with severe ALRI. Vitamin A treatment of children with severe ALRI had no significant beneficial effect.

Oxidation of plasma proteins is not increased after supplementation with eicosapentaenoic and docosahexaenoic acids

It is generally thought that as the intake of dietary polyunsaturated fatty acids increases, so should that of alpha-tocopherol, to protect the polyunsaturated fatty acids from increased in vivo peroxidation. However, there are little quantitative data about the concentration of alpha-tocopherol that is necessary when eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are consumed. The purpose of this study was to measure changes produced in 2 indexes of lipid oxidation after supplementation with EPA and DHA from fish oil and 3 doses of RRR-alpha-tocopheryl acetate in postmenopausal women. Daily supplements of fish oil providing 2.5 g EPA and 1.8 g DHA and 0, 100, 200, or 400 mg alpha-tocopheryl acetate were given to 46 postmenopausal women in a 4-treatment, 4-period crossover design. The supplements increased plasma concentrations of EPA, DHA, and alpha-tocopherol. The fish-oil supplement increased the plasma concentration of thiobarbituric acid-reactive substances (TBARS) (P: = 0.0001) but not that of oxidatively modified protein, as indicated by the carbonyl content. The alpha-tocopheryl acetate and fish-oil supplements had no significant effect on plasma concentrations of TBARS or oxidized protein. Although these data show a small but statistically significant increase in oxidative stress on the basis of plasma TBARS concentrations after the consumption of EPA and DHA, the clinical relevance of this change is questionable. In addition, as supplements of alpha-tocopheryl acetate were added to the diet, neither the plasma TBARS concentration nor the protein oxidation changed. Consequently, the results of this study indicate that there is no basis for vitamin E supplementation after consumption of EPA and DHA.

The relation between total cobalt and cobalt in vitamin B 12 during the maturation of ovaries in salmon ( salmo salar)

1. 1. Total cobalt and the content of vitamin B 12 were determined in samples from different stages of the reproductive cycle in ovaries of salmon. 2. 2. The relation between corresponding values for cobalt determined by AAS and calculated on the basis of vitamin B 12 determined microbiologically showed a striking correlation at all stages. Calculated as percentage of the values for vitamin B 12, between 99·8 and 104·5 per cent of the total cobalt were found to derive from the vitamin. 3. 3. The finding indicates a transportation of vitamin B 12 to the ovaries and an apparent blockage of cobalt ions.

Effects of Different Levels of Pyridoxine Fed during Pregnancy Superimposed upon Growth in the Rat

Effects of pregnancy superimposed upon a rapid phase of growth in the rat on the vitamin B-6 needs during gestation were examined. Rats were fed 1.2, 2.4, 4.8, 9.6, or 19.2 mg pyridoxine-HCl/kg diet from weaning. Some animals from each dietary treatment were mated at 55 (P-55) and 115 (P-115) days of age; others of the same ages served as nonpregnant controls. Analyses were made on day 21 of gestation. Excepting the 1.2-mg diet treatment, maternal weight gains during gestation were greater for P-55 groups compared with gains of the P-115 groups, possibly reflecting maternal growth. Both maternal weight gains and fetal weights were less for the 1.2-mg, P-55 group; otherwise reproductive performance was similar among the groups. On the basis of stimulation of erythrocyte alanine aminotransferase activity by pyridoxal phosphate added in vitro, the needs in all pregnant and nonpregnant groups were met by 2.4 mg pyridoxine/kg diet. However, on the basis of vitamin B-6 saturation of tissues, the pyridoxine needs were 9.6 mg/kg diet for young growing animals and 4.8 mg/kg diet for older animals in which growth had almost ceased. The needs for both young and older pregnant animals possibly exceeded 19.2 mg pyridoxine/kg diet for vitamin B-6 saturation of maternal liver, fetus, and fetal brain. Pregnancy superimposed upon a rapid phase of growth in conjunction with a restricted intake of pyridoxine resulted in low values for most parameters used in the assessments compared with values for animals fed the same vitamin level but mated after growth velocity had diminished.

A study of oil extraction from fish livers

SummaryResults obtained by steam, water, alkali, and acid digestion of shark and groper livers have been compared on the basis of vitamin A recovery, and alkali digestion, under the conditions reported, has been found to be the best method for livers with an oil content from 30% upwards. The partial removal of natural antioxidants from oil by alkali treatment does not seem to impair the stability of vitamin A on exposure to daylight and air at room temperature.