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PubMed1984

Effect of vitamin C deficiency on hydroxylation of trimethylaminobutyrate to carnitine in the guinea pig.

The effect of ascorbate deficiency on carnitine biosynthesis was investigated in young male guinea pigs. Liver and skeletal muscle carnitine levels were reduced in scorbutic animals. Heart and kidney concentrations remained unchanged. 14C-labeled 4-N-trimethylaminobutyrate was administered to control, pair-fed and scorbutic animals and distribution of isotope in compound present in the liver after 30 min was determined. Control and pair-fed animals converted trimethylaminobutyrate to carnitine faster than scorbutic animals. Injection of ascorbate with the [14C]trimethylaminobutyrate reversed the decline in trimethylaminobutyrate hydroxylase (EC 1.14.11.1) activity in scorbutic animals.

Animals↗

PubMed1982

Acute and chronic vitamin C deficiency in guinea-pigs: its effect on ceruloplasmin and cytochrome P 450 and b5 levels.

Serum and liver ceruloplasmin levels rose markedly in guinea pigs with acute scurvy and with chronic latent scurvy. Their increase in the former condition can be attributed to the general stress reaction, but the increase in ceruloplasmin levels in concentration may have a stimulant effect on the ceruloplasmin, when the oxidation of Fe2+ to Fe3+ is potentiated, may obstruct the binding of iron to protoporphyrin and prevent formation of the haeme of cytochrome P 450 and b5.

Animals↗

PubMed2000

[Effects of biologically active food additives with different contents of vitamins on the vitamin status in humans].

The comparative study of influence of two biologically active food additives with the different contents of vitamins is carried out: a drink "Zolotoi Shar", the dose of vitamins in which makes 50-90% from recommended daily consumption, and "Vitabalance 2000", the contents of vitamins in which at 2-17 of time exceeds need of organism. The use of both additives within 3 weeks resulted in increase of levels of vitamins C, A, E, B2, B6 and carotenoids in blood serum. However if in case of consumption of a drink an authentic level was reached only for vitamin C and beta-carotene, in a case "Vitabalance 2000" for all investigated vitamins except vitamin A. Thus, if the consumption of a drink has lowered frequency of deficiency of 3-4 vitamins, but has not allowed to liquidate it completely, in case of "Vitabalance 2000" consumption the simultaneous deficiency 3-4 vitamins. The received data allow to believe the biologically active food additives containing vitamins in amounts exceeding recommended consumption, are convenient for fast liquidation of hypovitaminoses, and the preparations containing vitamins in doses making 30-50% from need of organism, are acceptable for daily filling of insufficient consumption of vitamins with a usual diet for a long time.

Adenine↗

PubMed2003

Effect of orange and apple juices on iron absorption in children.

OBJECTIVE: To measure iron absorption in children from meals containing apple juice or orange juice so as to determine if iron absorption will be greater with orange juice because of its higher ascorbic acid content than apple juice, a noncitrus fruit juice that US children reportedly prefer. DESIGN: On 2 successive days, children consumed identical meals that included apple juice on one day and orange juice on the other, in random order. The meals were labeled with iron-57 on one day and iron-58 on the other. Iron absorption was measured from red blood cell incorporation of the iron stable isotopes 14 days later. SETTING: Nutrition research institute in a major metropolitan medical center. PATIENTS: A total of 25 healthy children, 3 to 6 years of age, were recruited, of whom 21 (11 male and 10 female) completed the study. Intervention Identical meals served with orange juice and apple juice were given on consecutive days, in a balanced randomized design. MAIN OUTCOME MEASURES: Iron absorption measured by established stable isotope methods. RESULTS: Median iron absorption from the meal ingested with apple juice was 7.17% (mean +/- SD, 9.48% +/- 9.68%). Median iron absorption from the meal ingested with orange juice was 7.78% (9.80% +/- 6.66%; P =.44). Iron absorption from the meal that included apple juice was significantly correlated with serum ferritin concentration (P =.02); iron absorption from the meal that included orange juice tended to correlate with serum transferrin receptor concentration (P =.051). CONCLUSIONS: As children absorb iron well from a meal that includes either orange or apple juice, a preference for apple juice does not pose a concern with regard to the prospect of iron-deficiency anemia, which remains a significant health problem in the United States.

Anemia, Iron-Deficiency↗

PubMed1979

Vitamin C deficiency in guinea pigs: changes in urinary excretion of proline, hydroxyproline and total amino nitrogen.

1. The age-related decrease in hydroxyproline : creatinine ratio in young guinea pigs was significantly smaller in vitamin C-deficient animals than in pair-fed controls. The same was true for proline : creatinine and total amino nitrogen : creatinine ratios, but hydroxyproline : total amino nitrogen and proline : total amino nitrogen ratios were not significantly affected by deficiency. 2. Although the proline : hydroxyproline ratio was unaffected in unfractionated urine, acute or chronic deficiency produced a small but significant increase in this ratio in collagenase digests of the acetone-insoluble fraction. 3. In scorbutic animals, therefore, collagen probably turns over more rapidly than in animals matched for inanition. Some at least, of this increase could represent the rapid turnover of underhydroxylated nascent collagen. Because it contains the degradation products from collagen from many tissues, differing widely in sensitivity to vitamin C status, the urine is unlikely, however, to provide a specific and sensitive functional index of vitamin C status.

Animals↗

PubMed1975

The inhibition of granuloma formation around Schistosoma mansoni eggs.

The effect of protein, calorie, and vitamin deficiency states on the granulomatous response of mice to eggs of S mansoni injected into the microvasculature of the lungs was studied. Moderate to severe protein and calorie deficiencies, as well as thiamine and vitamin C deficiencies, inhibited the host's granulomatous response to S mansoni eggs, which is a form of delayed-type hypersensitivity. The antivitamins neopyrithiamine hydrochloride and desoxypyridoxine hydrochloride were both highly effective in suppressing granuloma formation, but the former proved highly toxic at the doses utilized. Desoxypyridoxine hydrochloride given at a dose of .05 mg/mouse/day produced almost complete inhibition of granuloma formation; marked suppression was also present at fivefold dilution. This antivitamin appearts to be one of the most powerful immunosuppressive measures so far examined.

Animals↗

PubMed1981

Food patterns in modern society and their consequences on nutrition.

In conclusion we may state that a borderline vitamin deficiency exists in many population groups as well as in single persons even in industrialized countries. The reason for this fact is mainly the low education which is often associated with a low socioeconomic status and certain food patterns which derive from tradition, emotion or from other reasons not yet well understood. We have proved that the avoidance of pork and whole-wheat bread leads to a borderline vitamin B1 deficiency and the avoidance of citrus fruits, fruits, vegetables, viscera and potatoes to a broderline vitamin C deficiency. On the other hand, preference of meat did not show any adverse effect in respect to the vitamin B6 status. We believe that this kind of studies has to be continued, since the aim of nutritional surveys should consist in improving the nutritional status of the general population or of population groups. Therefore, it should be investigated why in certain population groups poor nutrition exists. Only the answer to this question could help us to combat malnutrition in industrialized countries in the best way.

Adult↗

PubMed1975

Effect of vitamin C supplementation on black mineworkers.

Subclinical vitamin C deficiency frequently occurs in Black mineworkers, in spite of an apparently adequate daily intake. A study was undertaken to establish the minimum rate of supplementation that would effectively reduce the incidence of subclinical vitamin C deficiency. Two levels of supplementation were tested in relation to a control group. It was found that a supplementation rate of at least 235 mg/head/day is required to maintain reasonably adequate serum levels. It was also found that effective control measures are required to ensure that the supplement is added to the magou, the staple beverage of the miners. It is strongly recommended that the intake of every Black mineworker be supplemented at a rate of 200 - 250 mg/day.

Black or African American↗

PubMed1980

Effect of vitamin C on copper and iron metabolism in the guinea pig.

Although interaction of vitamin C, copper and iron have been studied in several species, little is known about these interactions in species which require the vitamin in the diet. Young male Hartley guinea pigs were fed a basal diet, or a basal diet and supplemented daily with vitamin C, p.o. Pharmacologic doses (25 mg per 100 g BW per day) of vitamin C resulted in two-to-three-fold decreases in liver copper, when compared with those receiving normal (0.5 mg per 100 g BW per day) intakes. Under conditions of vitamin C deficiency, serum copper and ceruloplasmin were elevated along with liver copper. Serum and hepatic iron levels, hepatic microsomal cytochrome P-450 and cytochrome b5, and blood heme parameters all appeared to be directly related to vitamin C intake, i.e. the iron and heme parameters increased as the vitamin dose increased. These data are consistent with the hypothesis that interaction between vitamin C, copper and iron influence normal heme formation through the oxidation/reduction of iron and/or by regulating iron absorption and availability at the gut level.

Animals↗

PubMed1999

[Vitamin C in medicine: "normal concentration" in serum].

Vitamin C functions in a human organism have been discussed. Connection with many diseases and its systemic deficiency has been emphasized. A review of current application of this vitamin in medicine has been made. Problems accompanying the use of reference sources of vitamin C "normal concentrations" in blood plasma have been characterised. 10 ranges of concentrations given by medical handbooks and textbooks have been compared in detail with 15 parallel ranges taken from scientific papers, paying attention to their significant discrepancies. Basing on source values, performing basic statistical calculations, a reliable mean range of vitamin C "normal concentrations" in blood plasma has been obtained: 36.1-79.4 mumol/l.

Ascorbic Acid↗

PubMed1984

Vitamin C, oral scurvy and periodontal disease.

Scurvy and periodontitis both manifest gingival bleeding but constitute separate entities. Defective collagen in scurvy reflects many symptoms emanating from deficient vitamin C physiology. The various periodontal diseases are caused by oral plaque micro-organisms, the body's reaction to which is strongly influenced by inadequate functioning of leucocytes and monocytes. Although certain infections and systemic diseases cause gingival bleeding, avitaminosis C does not cause commonly encountered periodontal disease, but will aggravate established periodontitis. Vitamin C should not be used for prophylaxis or cure of periodontitis in healthy well-nourished individuals. A patient with bleeding gingivae warrants referral to oral medicine and periodontics specialists for examination and treatment.

Adult↗

PubMed1981

Clinical signs found in association with nutritional deficiencies as related to race, sex, and age for adults.

Clinical signs of various nutritional deficiencies for 429 adults were compared by race, age, and sex. The nutrients studied were vitamin A, riboflavin, vitamin C, vitamin D, and calcium. The prevalence of clinical signs of deficiency for all nutrients was much higher in blacks than in whites. Clinical lesions due to multiple nutrient deficiencies showed the same racial difference. Men had a higher prevalence of clinical signs for all nutrient deficiencies, except for vitamin A, that did the young. The racial and age differences in the nutritional status may be explained by the difference of educational and income levels. In comparison to the results reported from the Health and Nutrition Examination Survey (HANES), 1971 to 1974, the white subjects in this study had slightly higher prevalences of clinical signs than did those in HANES. Also, the prevalence of these clinical signs is much higher in the black subjects of the present study than in those of HANES.

Adult↗

PubMed1977

Scurvy; a comparison between ultrastructural and biochemical changes observed in cultured fibroblasts and the collagen they synthesise.

Earlier biochemical investigations of cultured 3T6 fibroblasts have shown that ascorbate deficiency has no effect on the synthesis of collagen protein quantitatively but does produce inhibition of the critical post-translational hydroxylation of collagen essential for normal fibrogenesis and of formation of hydroxylysine-derived cross-links. This ultrastructural study on the same 3T6 fibroblast system demonstrates that ascorbate deficiency does not affect the cell morphology, particularly that of the protein synthetic or secretory apparatus, but does prevent the deposition of typical 640A degrees banded collagen fibres; instead, finer, unbanded fibrils--presumably collagenous--are deposited extracellularly. This confirms the earlier biochemical findings as wll as presenting a new finding--the inability of ascorbate-deficient cells to lay down normal collagen fibrils; possible mechanisms are considered in terms of the known biochemical lesions. The tissue culture findings are also compared with those observed in vivo in the scorbutic guinea-pig, where other workers have reported biochemical and ultrastructural evidence that collagen synthesis is inhibited. The apparently paradoxical observations in the two systems are considered; we conclude that the tissue culture system demonstrates the primary collagenous lesion which is perhaps obscured in vivo by secondary effects--nevertheless the two approaches are complementary.

Animals↗

PubMed2003

Zeaxanthin deficiency enhances the high light sensitivity of an ascorbate-deficient mutant of Arabidopsis.

The ascorbate content of plants is usually increased in high light (HL), implying a function for ascorbate in the acclimation of plants to HL. Nevertheless, the importance of ascorbate in HL acclimation has not yet been tested directly. Here, we report on the acclimation process of an ascorbate-deficient Arabidopsis mutant to HL. The mutant vtc2 has only 10% to 30% of wild-type levels of ascorbate, and it is also slightly deficient in feedback de-excitation (qE), a photoprotective mechanism that causes the dissipation of excess light as heat. The vtc2 mutant was unable to acclimate to HL, when transferred from low light to HL. Its mature leaves bleached, and it showed an increased degree of lipid peroxidation and photoinhibition. In parallel, we tested the photosensitivity of an ascorbate-deficient xanthophyll cycle mutant, vtc2npq1, which also lacks zeaxanthin and nearly all qE. The double mutant bleached sooner and had higher degrees of lipid peroxidation and photoinhibition than the vtc2 mutant. This was in contrast to the npq1 single mutant that showed only slight deviations from the wild-type phenotype under the conditions used. These results demonstrate the antioxidant role of ascorbate in the acclimation process to HL and point to the relative importance of ascorbate in comparison with other photoprotective processes, such as specific xanthophylls or feedback de-excitation. The results also provide further support for the proposed role of zeaxanthin as an antioxidant and lipid stabilizer.

Arabidopsis↗

PubMedDate not supplied

[Provision of residents of the city of Kiev with vitamins C and B1. Effectiveness of a complex vitamin-mineral preparation in preventing spring vitamin deficiencies].

The investigation was conducted on provision with vitamins C and B1 of Kyiv inhabitants limited contingent at spring period and efficiency of complex vitamin-mineral preparations in normalisation of the vitamins level in blood of human-subjects. The deficit of vitamin C in 54% and vitamin B1 in 18.5% of the investigated people was revealed. Supradin gave the best results among rest preparations ("Centrum", "Vitrum", "Duovit", "Multi-Tabs") in the normalization of the level of vitamin C and biologically-active form of thiamine (thiamindiphosphate) in the blood of investigated people.

Ascorbic Acid↗

PubMed1988

[The pathological study of enterosiderosis in guinea pigs].

Enterosiderosis in both SPF Hartley guinea pigs and vitamin C-deficient animals of the same strain were studied by light and electron microscopy. Enterosiderosis was detected in all animals in the present study. Macrophages, inclosing yellowish-brown pigments and erythrocytes, appeared in the lamina propria of the intestinal mucosa, mainly in the cecum. These pigments in the macrophages were positive for Prussian blue, PAS and the Nile blue reaction. Residual bodies containing highly electron-dense ferritin-like particles, lipofuscin granules and debris of phagocytized erythrocytes were found by electron microscopy in the macrophages. In vitamin C-deficient guinea pigs, the number of macrophages, including the same above pigments, appeared in the lamina propria of the intestinal mucosa, and there was severe enterosiderosis. In the absorptive cells of the intestinal mucous membrane, granules positive for the Prussian blue reaction appeared only in the duodenum. These findings strongly suggest that the pigments in the macrophages in enterosiderosis of the guinea pigs were mixtures of iron and lipofuscin granules and that the iron is derived from erythrocytes phagocytized by macrophages in the lamina propria, but not from iron absorbed by epithelial cells.

Animals↗

PubMed1988

Thiamin, riboflavin, and vitamins B-6 and C: impact of combined restricted intake on functional performance in man.

A double-blind study of combined restriction of thiamin, riboflavin, and vitamins B-6 and C was carried out with 23 healthy males. During 8 wk of low vitamin intake, 12 deficient subjects consumed daily a diet of normal food products, providing maximally 32.5% of the Dutch Recommended Dietary Allowances (RDA) for thiamin, riboflavin, vitamins B-6 and C. Other vitamins were supplemented at twice the RDA. Eleven control subjects consumed the same diet but with a supplementation of twice the RDA of all vitamins. In deficient subjects blood vitamin levels, urinary vitamin excretion, and erythrocytic enzyme activities decreased; in vitro enzyme stimulation increased. Vitamin depletion had no ill effects on health, physical activity, and mental performance. A significant decrease was observed in aerobic power (VO2max) and onset of blood lactate accumulation (p less than 0.001) of 9.8 and 19.6%, respectively. A combined restricted intake of thiamin, riboflavin, and vitamins B-6 and C causes a decrease in physical performance within a few weeks.

Adult↗

PubMed1997

Oral scurvy and periodontal disease.

Although gingival bleeding is a manifestation of both scurvy and inflammatory periodontal disease, the two conditions are distinctly separate entities. The defective collagen synthesis associated with scurvy also manifests many of the same symptoms as deficient vitamin C physiology, but neither condition is associated with periodontal disease. Unlike scurvy, the various periodontal diseases are caused by oral plaque microorganisms. The body's reaction to these microorganisms is strongly influenced by the compromised functioning of leucocytes and monocytes. Although certain infections and systemic diseases cause gingival bleeding, avitaminosis-C does not cause commonly encountered periodontitis. Vitamin C should not be used for the prophylaxis or cure of periodontal disease in otherwise healthy, well-nourished individuals. A patient with bleeding gingivae warrants referral to a periodontist, oral medicine specialist, or appropriately qualified dentist for examination and treatment.

Ascorbic Acid↗