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PubMed2004

Effect of restricted feed intake and addition of vitamins B2 and B6 and folic Acid on the liver concentration of zinc and copper in rats.

The aim of the present study was to investigate the influence of nutritional deficiency and dietary addition of vitamins (B2, B6, and folate) on hepatic concentration of zinc and copper in rats. The experiment was performed on 260 growing male Wistar rats divided into 13 groups. Animals of 11 groups were fed isocaloric diets (14.7 MJ/kg) in which the 20% of energy was derived from protein. Another two groups of rats were offered diets with 9% or 4.5% of energy originating from protein. Animals of both mentioned groups and of the control group (20% of energy from protein) were offered diets ad libitum. The other 10 groups were offered 50% and 30% of the amount consumed in the control group. Eight groups, from those 10 restricted ones, were differentiated by dietary addition of vitamins B2 and B6 and folate (300% addition). Restricted feed intake did not affect the liver zinc concentration but significantly increased the copper concentration. The addition of vitamin B6 decreased the liver Zn concentration. The highest liver Cu concentration was noted in rats offered restricted diets to only 30% of intake in the control group and high in vitamin B2 and in rats supplemented with all of studied vitamins together. It suggests that vitamin B2 had the strongest impact on liver Cu concentration in rats fed restricted diets.

Animal Feed↗
PubMed1995

Fluorometric riboflavin titration in plasma by riboflavin-binding apoprotein as a method for vitamin B2 status assessment.

A method for plasma riboflavin determination by riboflavin-binding apoprotein titration has been proposed for vitamin B2 status evaluation. The method is based on the formation of riboflavin-apoprotein complex accompanied by full loss of fluorescence peculiar to free riboflavin. The data obtained have demonstrated a correlation with indicators of the vitamin B2 status such as urinary excretion, erythrocyte content, and stimulation of the glutathione reductase activity by flavin adenine dinucleotide. Levels > 6 ng/ml blood plasma may be considered to be a criterion for normal vitamin B2 supply.

Adolescent↗
PubMed1995

Intrauterine vitamin B2 uptake of preterm and full-term infants.

Intrauterine uptake of vitamin B2 in preterm and full-term infants was examined. Factors of influence on vitamin supply were considered. Forty-four women and their infants were included in the study. Fetal vitamin uptake was calculated as arteriovenous concentration gradient in cord plasma times umbilical plasma flow. Concentration of vitamin B2 (free riboflavin and flavocoenzymes) was determined by high performance liquid chromatography of placental tissue and blood plasma (maternal vein, umbilical artery, umbilical vein). Flavocoenzymes were analyzed as flavin mononucleotide after acid hydrolysis of flavin adenine dinucleotide. Umbilical plasma flow was measured using pulsed Doppler sonography. Both free riboflavin and flavocoenzymes were transferred from the maternal plasma to the umbilical vein, but only free riboflavin was accumulated (approximately 1:4 for preterm and full-term infants, respectively). Flavocoenzyme concentration was higher in the umbilical vein than in the umbilical artery (p < 0.05). This indicated a median uptake of flavocoenzymes of 1.5 nmol/min.kg in preterm infants and 0.4 nmol/min.kg in full-term infants (preterm versus full-term, p < 0.01). Fetal vitamin supply depended on umbilical plasma flow and on maternal vitamin status (the latter was shown only in full-term infants). No dependence on placental vitamin concentration was observed (p > 0.05). Concentration of free riboflavin was higher in umbilical artery than in umbilical vein (p < 0.05). This indicated a release of free riboflavin from fetal tissues independent of gestational age (0.4 nmol/min.kg, preterm; 0.2 nmol/min.kg, full-term; p > 0.05).

Adult↗
PubMedDate not supplied

[Effect of various supplies of vitamin B2 in the rat body on the activity of enzymes participating in the metabolism of xenobiotics].

Studies on the effect of different content of vitamin B2 (alimentary deficiency, additional administration) in the rat organism on the activity of enzymes participating in the metabolism of foreign substances and on the inducing effect of phenobarbital have shown that vitamin B2 to a considerable extent controls the activity of flavin-containing enzymes participating in the metabolism of xenobiotics (D-amino acid oxidase, xanthine and aldehyde oxidases, NADH- and NADPH-reductase activity of neotetrazolium) and a number of enzymes for which flavins do not play the role of prosthetic group (esterases aldehyde and formaldehyde dehydrogenases, demethylase and hydroxylase). Different content of vitamin B2 in animal organism also influences the action of phenobarbital, an inductor of xenobiotics metabolism, and the acetanilide biotransformation rate.

Acetanilides↗
PubMed1989

The effect of vitamin B2 and its derivatives on a dry-reagent strip theophylline assay.

This report describes the effect of flavin adenine dinucleotide (FAD) and its precursor vitamin B2 on an apoenzyme reactivation immunoassay system (ARIS) both in vitro and in vivo. It was observed that 10 nM/L FAD in the buffer causes a false-positive result in ARIS for theophylline by the value of 94 microM/L, whereas vitamin B2, flavin mononucleotide, adenosine, adenosine monophosphate, and adenosine diphosphate (ADP) at the same concentration caused no such effect. Nevertheless, ADP at 2 microM/L can cause a drop in theophylline reading of 55 microM/L. However, the sera from four volunteers with normal liver functions who had taken 30 mg of vitamin B2 daily for a week showed no effect on theophylline reading.

False Positive Reactions↗
PubMed1995

Effects of vitamin B2 on neutrophil functions in cattle.

Vitamin B2 was intramuscularly administered to Holstein cattle and the ensuing changes in peripheral blood neutrophil function were investigated. The neutrophil count displayed a significant increase at 1-2 days after administration, while nitroblue tetrazolium reducing activity and phagocytic bactericidal activity were enhanced at 1-4 days after administration in calves and at 1-6 days after administration in adult cows. The increases in the neutrophil count and the activation of neutrophil functions were observed, being manifested at dosages of 10 mg/kg or greater for calves and 5 mg/kg or greater for adult cows.

Aging↗
PubMed1991

Effect of vitamin B2 deficiency on rat liver dihydropyrimidine dehydrogenase activity.

Effect of vitamin B2 deficiency on rat liver dihydropyrimidine dehydrogenase was investigated. It was found that the purified enzyme contains 2 mol flavin per molecule, which consists of equal proportions of flavin-adenine dinucleotide (FAD) and riboflavin 5'-phosphate (FMN). When rats were fed on a vitamin B2-deficient diet for 5 weeks, dihydropyrimidine dehydrogenase activity in the liver was diminished, followed by a decrease in enzyme concentration. Moreover, the addition of exogenous FAD or FMN did not restore the activity. Thus endogenous flavin may regulate the enzyme half-life or synthesis. Lowering of dihydropyrimidine dehydrogenase activity in the livers of rats fed on a vitamin B2-deficient diet did not affect the uridine, uracil and sigma UMP (the sum of acid soluble uracil 5'-nucleotides) pool in liver.

Animals↗
PubMedDate not supplied

[Refining criteria for providing the body with vitamin B2].

The following patterns should be recommended as a criterion of normal vitamin B2 requirements: the FAD-effect is no more than 1.25, the levels of riboflavin, more than 5 ng/ml in the plasma and more than 130 ng/ml in the erythrocytes. At the same time, the hourly urinary riboflavin excretion more than 10 g/h may be used as a criterion of normal vitamin B2 requirements in children of 5-7 years old. These values were obtained while analysing the many-year experimental data on riboflavin treatment and using the mathematical analysis of the dependence curves for the urinary riboflavin excretion, its levels in plasma and erythrocytes, and the value of the FAD effect, as well as deriving and mathematically interpreting the variation curvers for the distribution of the given value of the FAD effect and the plasma riboflavin levels for human beings after additional vitamin therapy.

Adolescent↗
PubMedDate not supplied

Simultaneous determination of vitamins B2 (riboflavin) and B6 (pyridoxine) in infant formula products by reverse phase liquid chromatography.

An ion pair liquid chromatographic (LC) method is described for the simultaneous determination of vitamins B2 and B6 in infant formula products. The method eliminates many of the UV absorbing ingredients present in the infant formulations. The method involves extraction of the vitamins with distilled water followed by a filtration step and the subsequent analysis of the filtrate by LC. Vitamins B2 and B6 and their vitamers are separated from each other as well as from ingredients in the sample matrix on a 5 microns Spherisorb ODS column. The mobile phase consists of 85% 0.04 M triethylammonium phosphate (pH 3.0), 10% methanol, 5% acetonitrile, and the counter ion, octane sulfonic acid sodium salt. The method is reproducible for both vitamins with relative standard deviations (RSD) ranging from +/- 0.3 to +/- 2.6% depending on the infant formula product. The recoveries of the vitamins from various infant formula products are greater than 97%. The analysis for vitamins B2 and B6 in various lots of infant formula compared well with the official AOAC methods.

Chemical Phenomena↗
PubMed2004

Highly purified vitamin B2 presents a promising therapeutic strategy for sepsis and septic shock.

Highly purified vitamin B2 (riboflavin 5'-sodium phosphate; purity > 97%) treatment by intravenous infusion at doses above those used clinically to treat vitamin B2 deficiency showed therapeutic effects in mice not only in cases of endotoxin- and exotoxin-induced shock but also in cases of gram-negative and gram-positive bacterial infection even after the toxemia had already begun.

Animals↗
PubMed1990

[Mutagenesis of vitamin B2 producer by using protoplasts].

Studies on preparation, regeneration and ultraviolet-mutagenesis of protoplasts of vitamin B2 producer Eremothecium aohbyii were reported. By using a complex enzyme system (0.5% snial digestase + 0.5% cellulase), a great number of protoplasts were obtained. Ultraviolet-mutagenesising positive mutation ratio is 14.29%. The HPLC analysis indicated that a lot of mutants were screened by using ultraviolet-mutagenesis mutation of protoplasts, Vitamin B2 produced by the mutant E3 increased 116.4%.

Mutation↗
PubMedDate not supplied

[Use of the magnitude of vitamin and vitamin metabolite excretion as indicators of availability of vitamins B2, B6, and niacin].

Alimentary deficiency of riboflavin in rats caused a decrease in excretion of vitamin B2 with urine simultaneously with lowering in daily excretion of 4-pyridoxylic acid (4-PA) and N1-methyl nicotinamide (N1-MNA); these patterns are usually used as indicators of pyridoxine and niacin availability. The similar decrease in excretion of 4-PA and N1-MNA with urine but without alterations in NAD+NADP concentrations in erythrocytes was detected in women deficient in vitamin B2. Content of nicotinamide coenzymes in erythrocytes correlated with excretion of N1-MNA with urine only under normal conditions of riboflavin availability. Use of the criteria involving rates of 4-PA and N1-MNA excretion for evaluation of pyridoxine and niacin deficiency is discussed.

Adult↗
PubMedDate not supplied

[Effect of riboflavin (vitamin B2) on spontaneous gonarthrosis in the mouse].

Male mice of the C57 black strain were given 1 mg/kg body weight of riboflavin (vitamin B2) in their drinking water daily for 4 months, in addition to the vitamin B2 contained in their standard pellet feed. Controls received the standard feed only. Histological examination of the joints at the end of the experiment showed that the incidence of gonarthrosis in the group given supplementary riboflavin was less than half that found in the controls; the number of mice with bilateral gonarthrosis was also considerably smaller, and the severity of the lesions less marked. Signs of physiological degeneration in the epiphyseal cartilage of the femoral and tibial condyles were only marginally less pronounced than in the controls. The notable inhibitory effect of riboflavin, which is known to promote regenerative processes, on osteoarthritis was compared with that of drugs stimulating wound healing, e.g. flavonoids, tribenoside, and zinc sulfate. These latter substances were also found to exert a similar inhibitory effect on spontaneous gonarthrosis in the mouse.

Animals↗
PubMed2003

Assessment of thiamin (vitamin B1) and riboflavin (vitamin B2) status in an adult Mediterranean population.

The aim of the present study was to assess the nutritional status for thiamin (vitamin B1) and riboflavin (vitamin B2) in an adult Mediterranean population, in order to identify patterns of intake, groups at risk for deficiency and factors that might influence this risk. A cross-sectional survey was carried out in Andalusia, a western Mediterranean region in southern Spain. Nutrient intakes were studied in a random sample of 3390 subjects (1746 men, 1644 women) who were between 25 and 60 years of age. Blood samples were obtained for biochemical assays in a random subsample of 372 subjects (181 men, 191 women). Food consumption was assessed by 48 h recall. Vitamin B1 and B2 were measured as erythrocyte transketolase and as erythrocyte glutathione reductase activation coefficients, respectively. Energy and vitamin intakes were significantly higher in men than in women. Intakes were below two-thirds of the recommended dietary allowance for vitamin B1 in 7.80 % of the men and 4.50 % of the woman, and were below this level for vitamin B2 in 18.00 % of the men and 11.70 % of the women. Age, educational level, alcohol use and smoking were also associated with differences in the intake of these nutrients. Biochemical analyses showed that vitamin B1 and B2 status was deficient in 6.40 and 5.30 % of the population, respectively. Although factors such as gender, age, level of education, drinking and smoking can have an effect on the risk of inadequate intake of these nutrients, these factors did not affect biochemical indices of nutritional status in the present study.

Adult↗
PubMed1995

Enhancement of resistance to bacterial infection in mice by vitamin B2.

We found that the intramuscular injection of vitamin B2 enhanced host resistance to E. coli infection in a dose-dependent manner (6.25 mg/kg-100 mg/kg). Furthermore, VB2 exhibited the protective activity against Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, and Actinobacillus pleuropneumoniae. The mechanism of action of VB2 for enhancing resistance in mice may be, at least in part, its ability to stimulate the multiplication of neutrophils and monocytes, and to activate macrophages.

Actinobacillus Infections↗