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Vitamin K deficiency embryopathy: a phenocopy of the warfarin embryopathy due to a disorder of embryonic vitamin K metabolism.

Three unrelated infants presented with radiographic punctate calcifications, nasal hypoplasia, and abnormalities of the spine. Additional anomalies included cupped ears in 2 patients and one each with Dandy-Walker malformation with hydrocephaly, congenital cataracts, and peripheral pulmonary artery stenosis. The mothers of these 3 patients had chronic conditions associated with intestinal malabsorption requiring total parenteral nutrition for varying periods of time. The underlying causes of malabsorption were celiac disease, short bowel syndrome secondary to surgical resection, and jejuno-ileal bypass, respectively. Bleeding diathesis occurred in one mother requiring vitamin K supplementation during the second and third trimesters of pregnancy. We speculate that the chondrodysplasia punctata and other abnormalities in these children were caused by an acquired maternal vitamin K deficiency manifested during early pregnancy. However, the involvement of other vitamin deficiencies cannot be excluded. Thus, vitamin K deficiency of the embryo secondary to maternal malabsorption appears to be a third vitamin K-related mechanism leading to chondrodysplasia punctata in addition to warfarin embryopathy and epoxide reductase deficiency (pseudo-warfarin embryopathy).

Abnormalities, Drug-Induced↗

[Changes in the plasma concentration of vitamin A, vitamin E and beta-carotene in polytrauma patients and in patients with osteitis in relation to course of illness].

In 17 patients with osteitis and 16 polytraumatized patients changes in the plasma levels of vitamin A, vitamin E and beta-carotene were investigated. Plasma samples taken preoperatively, daily during the first three days and then twice a week postoperatively were analysed for fat-soluble vitamins by high performance liquid chromatography (HPLC). Significant changes in plasma levels of all three components depending on the outcome of injury were found in all patients. Increased levels were observed in patients that survived the injury, while in those who died a significant decrease was observed. Recommendations regarding the supplementation with these vitamins in clinical practice can not be made based on these results, but substitute might prove beneficial for vitamin E in certain types of injury.

Adult↗

The effect of massive doses of vitamin A on the signs of vitamin A deficiency in preschool children.

Marked seasonal variation in the prevalence of signs of vitamin A deficiency was found in the 2nd year of a continuing study of children age 0 to 4-1/2 years in a village in West Bengal, confirming results of a previous 18-month study. Administration of 200,000 IU of vitamin A every 4 months completely eliminated night blindness and prevented the development of new cases of Bitot's spot in a statistically significant number of children. The effectiveness of massive doses of vitamin A, administered at intervals of 4 months, as a short-term measure to fight the problem, was confirmed in this village. The study yielded additional evidence of the complex etiology of Bitot's spot, since alternate day dose of vitamin A in addition to massive therapy failed to eliminate these spots.

Child, Preschool↗

A community based study of vitamin A and vitamin E status of adolescent girls living in the Shire Valley, Southern Malawi.

OBJECTIVE: To assess vitamin A and E status and anaemia in non-pregnant Malawian adolescent girls. DESIGN: A cross-sectional study in rural village communities in the Shire Valley, Southern Malawi. SUBJECTS: Adolescent girls, n = 118, aged between 10 and 19 y, 112 of whom were unmarried. METHODS: Socio-demographic information was collected by questionnaire, heights and weights were measured. Vitamin A was assessed by the Modified Relative Dose Response (MRDR) test, in addition to serum retinol values. Blood samples were collected 4-5 h after administration of 3,4-didehydroretinyl acetate. Retinol and alpha-tocopherol levels were measured by HPLC. Serum retinol results for non-pregnant girls were compared with values for 43 adolescent pregnant girls which were available from a previous study. RESULTS: 26.6% of non-pregnant girls had serum retinol values < 0.70 micromol/L; 40.2% had an MRDR ratio > 0.060. In 59.3%, serum tocopherol levels were < 11.5 micromol/L and the tocopherol/cholesterol ratio was < 2.2 in 23.9%. 11.3% had a haemoglobin > or = 12 g/dl. Vitamin A levels were significantly related to age, and younger girls were more likely to be deficient. Significant correlations were found between serum retinol, MRDR values and serum tocopherol. Girls with a low body mass index for age had tocopherol cholesterol ratios < 2.2. Low serum retinol values occurred significantly more often in stunted girls (P=0.01). Serum retinol values of adolescent pregnant girls were significantly lower than those of non-pregnant adolescents (P=0.002). CONCLUSIONS: Vitamin A and E deficiency and anaemia were common in adolescent non-pregnant girls, and thought to partly result from increased growth requirements. Girls who become pregnant at an early age are at risk of depletion of their nutritional reserves. Measures to reduce nutritional deficiencies before the first pregnancy are needed.

Adolescent↗

Does a single vitamin B-supplementation induce functional vitamin B-deficiency?

In a pilot study we measured the effect of three different combinations of the vitamins B6, folate and B12 on the serum concentrations of homocysteine, cystathionine and methylmalonic acid in five healthy young men without hyperhomocysteinemia. The results indicate that there are still undescribed interactions between vitamin B6 and folate, suggesting that these two vitamins should be given together to avoid depletion of the one not given. With regard to the well known metabolic pathways of methionine and cysteine, this confirms the hypothesis that a combined supplementation with the vitamins B6 and folate (and B12) is superior to folate alone in order to lower homocysteine.

Adult↗

[Vitamins A and E and vitamin A-binding proteins in the blood serum of patients with esophageal cancer].

The mean values of the vitamin A and the beta-carotene in the blood serum of patients with oesophageal cancer are lower than that in patients with nonmalignant oesophagus diseases and those with diseases other than malignancies and oesophageal diseases. The total protein and the albumin concentration in the blood sera did not differ when the above three groups of patients were compared. The concentration of vitamin E in the blood serum was similar in all three groups studied. The concentration of vitamin A in the group of patients with oesophageal cancer showed a marked correlation with the concentration of the vitamin A-binding proteins in the blood serum.

Adult↗

[Vitamin and mineral deficiency in Mexico. A critical review of the state of the art. II. Vitamin deficiency].

We carried out a review of the studies related to vitamin deficiencies in the Mexican population published since 1950. Forty four studies were published from which we can conclude that: a) dietary intake data suggest that ascorbic acid, riboflavin and retinol intake are deficient: reported intakes were 40-70%, 35-64% and 20-72% of the recommended daily amounts respectively; niacin intake was also deficient in some studies; b) about 10% of Mexican children in rural areas had deficient values of plasma retinol (< 100 ng/ml) and about 25 to 30% had low values (100-200 ng/ml); this prevalence is reduced in children with a higher socioeconomic level; c) some studies were found that show the existence of marginal deficiencies of vitamin E, riboflavin and vitamin B12 in apparently healthy populations. Further studies are required to identify the magnitude of these and perhaps other vitamin deficiencies and their potential effects on the health and function of the Mexican population.

Adult↗

Vitamin D metabolite concentrations in vitamin D deficiency. Are calcitriol levels normal.

The levels of vitamin D metabolites were measured in three children with a decreased dietary intake of calcium and vitamin D and sun exposure. All three children had hypocalcemia, hypophosphatemia, and elevated alkaline phosphatase activities. Two children had rickets, aminoaciduria, and elevated immunoreactive parathyroid hormone (iPTH) concentrations. The concentrations of vitamins D2 and D3, 25-hydroxyvitamins D2 and D3 (25-OH-D2 and 25-OH-D3), and 24,25-dihydroxyvitamin D (24,25-[OH]2D) were reduced. Nonetheless, the levels of calcitriol (1,25-[OH]2D) were normal. The combination of hypocalcemia, hypophosphatemia, and increased iPTH concentrations should result in supranormal calcitriol concentrations. Moreover, the ratio of PTH to calcitriol is significantly higher than in normal subjects. Accordingly, in patients with vitamin D deficiency and "normal" calcitriol values, the synthesis of this compound may be reduced. The evaluation of vitamin D deficiency should include the measurement of all metabolites.

24,25-Dihydroxyvitamin D 3↗

Protective effects of selenium, vitamin C and vitamin E against oxidative stress of cigarette smoke in rats.

Cataractous lenses have been found to have an altered distribution of the intracellular ionic environment: the concentrations of potassium and magnesium being decreased and the concentrations of sodium and calcium increased. These changes arise as a result of changes to lens membrane characteristics causing an increase in lens membrane permeability. In this study flame atomic absorption spectroscopy (AAS) was used for calcium, magnesium, iron and zinc determination, and flame atomic emission spectroscopy (AES) was used for sodium and potassium contents in normal and cigarette smoke-exposed rat lenses. The methods are sensitive enough to detect quantitatively all six cations in a single rat lenses. In this work, six elements, including Ca2+, K+, Na+, Zn2+, Fe2+ and Mg2+ in experimental rat eye lenses and normal transparent lenses were determined. It was found that the concentrations of Ca2+, Na+, Zn2+, and Fe2+ were increased dramatically while K+ and Mg2+ decreased in smoke-exposed rat lenses when compared to the control rat lenses. There were no significant changes between 'smoked' rats supplied with vitamin C and control groups. A positive correlation was found also in the other two groups of 'cigarette smoked' animals supplemented with selenium plus vitamin E and selenium when compared with 'cigarette smoked' without any supplements. These data provide support for the hypothesis that cigarette smoking increases the risk of cataract formation. We investigated whether vitamin C is the most important antioxidant in the body. The roles of diet with optimum amounts of antioxidant vitamins C and vitamin E and the antioxidant mineral selenium are discussed.

Animals↗

The effect of light on the vitamin B2 and the vitamin A content of cheese.

Edam type cheese was exposed to sunlight at ambient temperature and to fluorescent light at 5 degrees C. The loss of vitamin B2 (riboflavin) and vitamin A was monitored in both the surface and inner layers of the cheese and the results compared with control samples kept in the dark. The loss of riboflavin when exposed to sunlight was shown to be primarily a surface effect but losses of vitamin A were similar throughout the cheese. When exposed to fluorescent light at 5 degrees C and monitored at intervals for 10 days the loss of riboflavin was still greatest at the surface but a trend to lower values than the control was evident throughout the cheese. Vitamin A losses followed a different pattern in both sunlight and fluorescent light. There was a heavy initial loss throughout the cheese. Under fluorescent light this was followed by a period in which further loss was mainly in the surface layer. Vacuum packaging reduced the loss of riboflavin but had no effect on the loss of vitamin A.

Cheese↗

25-Hydroxy[26,27-methyl-3H]vitamin D3-3 beta-(1,2-epoxypropyl)ether: an affinity labeling reagent for human vitamin D-binding protein.

Vitamin D-binding protein (DBP) is primarily involved in the binding and transportation of vitamin D3 and its various metabolites to target organs and tissues. This is manifested by the ability of DBP to bind vitamin D3 and its metabolites with high affinity. In the present study we developed 25-hydroxyvitamin D3-3 beta-(1,2-epoxypropyl)ether (25-OH-D3-epoxide) as an affinity labeling reagent of human DBP (hDBP). Competitive radioligand binding assays of 25-OH-D3-epoxide with hDBP demonstrated that the binding affinity of this analog was similar to that of 25-hydroxyvitamin D3 (25-OH-D3). Incubation of 25-hydroxy[26(27)-3H]-vitamin D3-3 beta-(1,2-epoxypropyl)ether [[3H]25-OH-D3-epoxide] with hDBP covalently labeled the protein. When the incubation was carried out in the presence of a large excess of 25-OH-D3, labeling was removed completely. When human Cohn IV fraction, containing hDBP, was incubated with [3H]25-OH-D3-epoxide a single protein band, corresponding to hDBP, was labeled. Labeling was completely obliterated in the presence of a large amount of 25-OH-D3. However, an equivalent amount of 7-dehydrocholesterol had no effect on labeling. These results demonstrated that [3H]25-OH-D3-epoxide most probably labeled the vitamin D sterol-binding domain of hDBP.

Affinity Labels↗

Antioxidant reactions of vitamin E in the perfused rat liver: product distribution and effect of dietary vitamin E supplementation.

We have investigated the relationship between vitamin E (alpha-tocopherol, TH) oxidation and antioxidant protection in a perfused rat liver model. Perfusion of a male Sprague-Dawley rat liver with 2 mM tert-butylhydroperoxide (t-BuOOH) for 10 min resulted in lipid peroxidation and metabolic changes reflecting oxidative stress. Mitochondria isolated from the liver exhibited increases in state 3 and state 4 respiration and a decline in the respiratory control ratio. In livers from rats given supplementary vitamin E in the diet, TH content was 7- to 10-fold higher than in controls and lipid peroxidation and metabolic changes induced by t-BuOOH were decreased. In mitochondria from these vitamin E-supplemented livers, the t-BuOOH-induced increase in state 4 respiration was reduced and the respiratory control ratio was maintained. In livers from unsupplemented rats, t-BuOOH induced oxidation of TH to alpha-tocopherolquinone, alpha-tocopherolhydroquinone, 2,3-epoxy-alpha-tocopherolquinone, and 5,6-epoxy-alpha-tocopherolquinone, as determined by gas chromatography-mass spectrometry analysis. Yields of these products were approximately doubled by treatment of samples with dilute acid, which indicated the presence of tocopherone and epoxytocopherone precursors. Oxidation of TH in vitamin E-supplemented livers yielded the same products and the relative extent of TH oxidation appeared similar to that in unsupplemented livers. In livers from both unsupplemented and vitamin E-supplemented animals, the distribution of oxidation products was similar in whole liver and isolated mitochondria. These data provide the first simultaneous documentation of TH antioxidant reactions and antioxidant effects in an intact organ system during oxidative stress.

Animals↗

Protection by vitamin C of loss of vitamin E in cultured rat hepatocytes.

Results from in vivo studies of the capacity of vitamin C to spare and/or recycle vitamin E are equivocal. While some in vitro and membrane models reveal an interaction between vitamins C and E, the characterization of this relationship in biologically relevant systems is lacking. Thus, we investigated this relationship using hepatocytes isolated from 3- to 6-month-old male Sprague-Dawley rats. Cells were incubated for 18-20 h in medium supplemented with 0.1-4 mM ascorbic acid. The loss of alpha-tocopherol and the formation of its primary oxidized metabolite, alpha-tocopherolquinone, was determined by HPLC. Levels of alpha-tocopherol in hepatocytes incubated without ascorbic acid declined from 390 to 35 pmol/mg protein; hepatocyte ascorbic acid levels declined from 9 to 0.5 nmol/mg protein. alpha-Tocopherolquinone was undetectable in freshly isolated hepatocytes but following incubation in ascorbate-free medium reached 10 pmol/mg protein. The formation of alpha-tocopherolquinone was not detected in hepatocytes incubated with ascorbic acid. Dehydroascorbic acid (DHA) levels represented 10-20% of the total ascorbate content in freshly isolated hepatocytes but after 3 h incubation the proportion of DHA increased to 50%; after 18-20 h incubation DHA was undetectable. Hepatocytes incubated with 1.0, 2.0, 2.5, or 4.0 mM ascorbic acid lost significantly less alpha-tocopherol (62, 69, 67, and 56%, respectively) than unsupplemented controls (90%). Twelve percent of the alpha-tocopherol lost from hepatocytes during incubation was detected in the medium of cells incubated with ascorbic acid, but vitamin E was undetectable in the medium of cells incubated without ascorbic acid. These results demonstrate an interaction between vitamins C and E in cell culture and are not inconsistent with a potential recycling of oxidized alpha-tocopherol by ascorbic acid.

Animals↗

Dietary vitamin D dependence of cat and dog due to inadequate cutaneous synthesis of vitamin D.

As in herbivores and omnivores, the biosynthesis of vitamin D3 in the skin exposed to ultraviolet (uv) light is generally expected to also occur in the dog and the cat. The purpose of this in vitro study was to measure the concentrations of vitamin D3 and its precursor 7-dehydrocholesterol (7DHC) in dog and cat skin before and after a quantitatively and qualitatively standardized exposure to uv light. The results are compared to those obtained by the same method in the skin of the rat. The efficiency of extracting 7DHC and vitamin D3 from skin was 72 +/- 8% and 67 +/- 3%, respectively. In dog and cat skin the concentrations of nonesterified 7DHC were below the detection limit of the HPLC system. Therefore, skin extracts were saponified and total 7DHC and vitamin D3 concentrations were measured by normal-phase HPLC. Before irradiation with uv-B light the total concentrations of 7DHC were 1858 +/- 183, 1958 +/- 204, and 17,620 +/- 2345 ng/cm2 skin (mean +/- SEM; n = 5) for the dog, the cat, and the rat, respectively. The corresponding concentrations of vitamin D3 were 211 +/- 44, 193 +/- 18, and 161 +/- 32 ng/cm2 skin for the dog, the cat, and the rat, respectively. Irradiation of standard solutions of 7DHC with 0.15 J uv-B light/min resulted in a time-dependent decrease in 7DHC and a concomitant increase in previtamin D3.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

[The formation of cis-isomers of all trans-vitamin A acetate during the alkylation step for determination of vitamin A in feeds].

The determination of vitamin A in animal feed by HPLC must be preceded by a saponification step in order to eliminate the interfering lipids. This operation bears the risk of isomerisation of the vitamin A. We have determined the degree of isomerisation by adding trans-vitamin-A-acetate (in dry powder form) to 8 different vitamin A free blends, followed by saponification, extraction and HPLC. In this study, we have taken into account all the 5 known cisisomers. The degree of isomerisation depends on the type of feed and on the conditions of saponification and ranged from 4 to 40%. Pure vitamin-A-acetat was isomerised to the extend of 1 to 30% depending on saponification conditions. The recovery rate was (with some exceptions) 90 +/- 5%.

Alkylation↗

[Reduced diclofenac administration by B vitamins: results of a randomized double-blind study with reduced daily doses of diclofenac (75 mg diclofenac versus 75 mg diclofenac plus B vitamins) in acute lumbar vertebral syndromes].

Pain syndromes of the lumbar spine are one of the main problems in orthopedic practice. The therapeutic effect of NSAIDs is not subject to doubt in this connection. But considering that the application of NSAIDs is frequently associated with side effects, a reduction of dosage would be to the patient's benefit. Clinical studies have shown that concomitant treatment with vitamins B1, B6, B12 and diclofenac leads to a more efficient pain relief than treatment using diclofenac alone and thus provides the possibility of saving NSAIDs. This clinical trial was carried out in order to determine whether these results can also be achieved when a reduced dosage of diclofenac (75 mg daily) is used. 123 patients with acute pain syndromes of the lumbar spine were treated with either B-vitamins and diclofenac or diclofenac alone for a maximum of 7 days. There was the option to terminate therapy in the trial after 3-4 days in the case of total pain relief. 45 patients could stop the treatment due to remission of symptoms. 30 patients belonged to the combination therapy group, the other 15 took diclofenac alone; this difference is statistically significant (p less than 0.05). All parameters concerning pain relief and movement of the vertebral column showed statistically significant differences in favour of the B-vitamin-diclofenac-combination, too. The results document the positive influence of B-vitamins on painful vertebral syndromes and indicate that B-vitamins contribute to saving of NSAIDs by shortening the treatment time and reducing daily NSAID-dosage.

Adolescent↗

Synthesis of a reagent for fluorescence-labeling of vitamin D and its use in assaying vitamin D metabolites.

The fluorogenic dienophile 1,2,4-triazoline-3,5-dione with a highly fluorescent quinoxalinone group at the 4-position (DMEQ-TAD) was synthesized and exploited as a reagent to assay vitamin D metabolites. 25-Hydroxyvitamin D3, 1 alpha,25-dihydroxyvitamin D3, and 24(R),25-dihydroxyvitamin D3 reacted quantitatively with DMEQ-TAD when the two substrates were mixed in dichloromethane at room temperature to yield the corresponding 6,19-cycloadduct. The reaction was very fast so that 1 alpha,25-dihydroxyvitamin D3 at a concentration as low as 10(-8) M could be quantitatively labeled with the fluorescent reagent within 30 min at room temperature. With this reagent, down to 10 fmol of vitamin D metabolites could be quantified linearly. The detection limit of the labeled vitamin D using high-performance liquid chromatography was usually about 1 fmol. Thus, it was shown in a model system that the fluorometric method using the new reagent (DMEQ-TAD) can be applied to the assay of the three major vitamin D metabolites in 1 ml of plasma. This is the first practical fluorometric method for assaying the active vitamin D metabolite.

24,25-Dihydroxyvitamin D 3↗

Lapachol inhibition of vitamin K epoxide reductase and vitamin K quinone reductase.

Lapachol [2-hydroxy-3-(3-methyl-2-butenyl)-1,4-naphthoquinone] has been shown to be a potent inhibitor of both vitamin K epoxide reductase and the dithiothreitol-dependent vitamin K quinone reductase of rat liver microsomes in vitro. These observations explain the anticoagulant activity of lapachol previously observed in both rats and humans. Lapachol inhibition of the vitamin K epoxide and quinone reductases resembled coumarin anticoagulant inhibition, and was observed in normal strain but not in warfarin-resistant strain rat liver microsomes. This similarity of action suggests that the lactone functionality of the coumarins is not critical for their activity. The initial-velocity steady-state inhibition patterns for lapachol inhibition of the solubilized vitamin K epoxide reductase were consistent with tight binding of lapachol to the oxidized form of the enzyme, and somewhat lower affinity for the reduced form. It is proposed that lapachol assumes a 4-enol tautomeric structure similar to that of the 4-hydroxy coumarins. These structures are analogs of the postulated hydroxyvitamin K enolate intermediate bound to the oxidized form of the enzyme in the chemical reaction mechanism of vitamin K epoxide reductase, thus explaining their high affinity.

Animals↗