Mahtab S. Bamji

Spirulina as a source of vitamin A

Experiments were carried out to assess spirulina fusiformis — a blue green algae as a source of vitamin A in rats. In one experiment, the control rats were fed synthetic vitamin A and the experimental rats spirulina as the sole source of vitamin A. The liver vitamin A concentration of spirulina-fed rats of both sexes was found to be significantly higher than that of the control rats. In another experiment the absorption of carotenes from the solvent extract of spirulina and their availability (vitamin A value) as judged by the levels of vitamin A and carotene in plasma and liver were compared with those of synthetic β-carotene or vitamin A in male rats. The absorption of β-carotene from spirulina extract tended to be lower than that of crystalline β-carotene at doses of 550 and 1100 μg of β-carotene. The difference became insignificant at lower β-carotene dose of 275 μg.Spirulina carotene-fed rats did not show a strict dose related increase in the liver or serum vitamin A concentration. The liver vitamin A storage and plasma levels of vitamin A of spirulina carotene-fed rats was much hither than expected. The results of the two studies reported suggest that the algae spirulina can be a valuable source of vitamin A.

Relationship between biochemical and clinical indices of B-vitamin deficiency. A study in rural school boys

1. A study amongst schoolboys in villages around Hyderabad, India, showed that almost all the boys had riboflavin deficiency, 61% had pyridoxine deficiency, and 9.4% had thiamin deficiency as judged by enzymic tests. 2. The prevalence of angular stomatitis was 41.3% and that of glossitis was 18.2%. Biochemical deficiency of riboflavin and pyridoxine was marginally higher in children with angular stomatitis with or without associated glossitis, than in children without oral lesions. 3. Treatment with B-complex vitamins (containing 4 mg riboflavin and 10 mg pyridoxine) daily for 1 month produced significant reduction in the prevalence of glossitis but had no effect on angular stomatitis. The latter responded to topical application of gentian violet. 4. Small but significant changes in erythrocyte enzymes occurred over the period of 1 month even without vitamin supplements. 5. Results suggest that while glossitis is a relatively early manifestation of riboflavin or pyridoxine deficiency or both, angular stomatitis has a more complex aetiology perphaps associated with infection.

Tissue pyridoxal phosphate concentration and pyridoxaminephosphate oxidase activity in riboflavin deficiency in rats and man

1. Parenteral administration of pyridoxal 5′-phosphate (PALP) to riboflavin-deficient rats increased the non-FAD component of erythrocyte riboflavin. 2. Pyridoxaminephosphate oxidase ( EC 1.4.3.5) activity in the livers of riboflavin-deficient animals was only 15% of that of controls. PALP concentration in blood, liver and brain was not affected. Deficient animals had higher levels of pyridoxine in liver. 3. Human subjects with lesions of the mouth responded to treatment with either riboflavin or pyridoxine. 4. PALP concentration of human blood was not affected by administration of riboflavin but was markedly increased by pyridoxine. 5. Erythrocyte glutathione reductase activity ( EC 1.6.4.2) in humans was increased and in vitro stimulation of the enzyme with FAD was decreased by treatment with riboflavin, but not by treatment with pyridoxine.

Impact of women's work on maternal and child nutrition.

The impact of womens participation in economic activity on nutrition status of the mother and her preschool‐age children was examined in 309 rural women selected by purposive sampling. Time spent on housework, child care, and economic activity on a typical day was ascertained by recall of time use on the previous day. Dietary intake was estimated by recall method. Nutrition status was assessed by anthropometry and clinical deficiency signs. In a sub‐sample finger‐prick blood was examined for haemoglobin and riboflavin status. The data were collected in three seasons. The effects of season and land holding as well as occupation were also examined. Malnutrition was widespread in both the mothers and the children. The time saved by house wives not engaged in economic activity was not adequately reflected in time devoted to child care. Minor influences of land holding, season, and mothers occupation on diet and nutrition of mothers and children were seen but the differences in most cases were statistically not significant. Working mothers and their children tended to show higher prevalence of signs of B‐complex deficiency than housewives and their children. Seasonal effects on vitamin deficiency signs were seen in children.

Mechanism of impaired skin collagen maturity in riboflavin or pyridoxine deficiency

To elucidate the biochemical basis of impaired skin collagen maturity in pyridoxine-or riboflavin-deficient rats the following two mechanistic possibilities were tested: (i) Reduction in the activity of skin lysyl oxidase (EC 1·4·3·13) which initiates the cross-linking of collagen and (ii) putative rise in homocysteine level leading to neutralization of allysine (α-aminoadipic acid δ-5-semialdehyde)or hydroxyallysine (hydroxy α-aminoadepic acid (δ-semialdehyde) in collagen by the formation of thiazine complexes.Skin lysyl oxidase activity was not affected in pyridoxine deficiency suggesting that pyridoxal phosphate may not be its cofactor. In riboflavin deficiency, lysyl oxidase activity was not altered in the newly regenerated rat skin but a slight reduction was observed in the skin of 18-day-old rat pups. This could be related to the body weight deficit rather than deficiencyper se. Aldehyde content of purified salt soluble collagen of regenerated skin was significantly reduced in both the deficiencies. A 2 to 4-fold increase in the concentration of skin homocysteine was observed in both the deficiencies. The results suggest that increase in skin homocysteine level may be responsible for the impaired skin collagen maturity in riboflavin or pyridoxine deficiency.

Vitamin Deficiencies in Rice-Eating Populations Effects of B-Vitamin Supplements

Rice is the staple food in many countries of Asia. Recent nutrition surveys in eight states, conducted by the National Nutrition Monitoring Bureau of India, show that though the average energy intake is adequate, more than 50% of the households surveyed consumed less than the Recommended Dietary Allowance (RDA) of energy. These households generally had per capita incomes of less than Rupees 2/- (US+ 0.25) per day. The average intake of vitamin A was only 42% of the RDA and that of riboflavin, 70% of the RDA. The average intake of other nutrients such as thiamin, niacin, ascorbic acid, iron and calcium was adequate, although thiamin deficiency was present in populations where rice was the main cereal, but not in populations where rice was the main cereal, but not in populations that consumed mixed cereal or cereal-millet diets. The magnitude of the riboflavin deficiency (after correction or energy) was also more marked in the former. Vitamin A intake was not related to the type of cereal, but had some relationship to the quantity of vegetables consumed. Nutrition surveys from Japan also reveal deficiencies in intake of energy, vitamin A, thiamin and riboflavin. The Japanese diet tends to be deficient by 20% in vitamin A and riboflavin, but not thiamin. Thus, vitamin A, riboflavin and energy (in that order) are the major nutritional constraints in rice-eating populations. Clear-cut correlations between the magnitude of dietary deficiency and the prevalence of signs and symptoms of vitamin deficiency were not apparent in the comparisons between populations, suggesting that as well as dietary deficiency other environmental factors play a role in the development of clinical deficiency. Attempts to correlate clinical deficiency with the magnitude of biochemical deficiency have also failed. Recent studies aimed at examining the effects of food supplements (rural Gambian women) or vitamin supplements (rural Indian boys) on vitamin status suggest that in some communities, vitamin intakes close to the RDA fail to saturate the tissues, as judged by biochemical tests. In the Indian boys, there was a marked rise in urinary excretion of riboflavin during winter when the incidence of respiratory infections was high. Metabolic losses of vitamins due to infections may preclude tissue saturation despite adequate dietary intake. Administration for 1 year of B-vitamins at levels close to the RDA failed to reduce the prevalence of clinical deficiency signs, but did produce some improvement in hand steadiness - a psychomotor test.(ABSTRACT TRUNCATED AT 400 WORDS)

Physiological implications of reduced glutathione reductase activity of red blood cells in human ariboflavinosis

Stability of erythrocyte-reduced glutathione in the presence of acetylphenyl-hydrazine (“glutathione-stability test”) was studied in healthy and riboflavin-deficient subjects. Many apparently healthy subjects showed poor stability, which improved after treatment with riboflavin. However, clinically riboflavin-deficient subjects with very low glutathione reductase activity, had satisfactory glutathione stability, which tended to show a slight fall after treatment. These results indicate the presence of a compensatory mechanism which helps the cell to overcome glutathione reductase deficiency. Riboflavin-deficient subjects had normal glucose-6-phosphate dehydrogenase levels and normal Km of glutathione reductase for NADPH. Destruction of glutathione by acetylphenylhydrazine occurs even in boiled erythrocyte hemolysate.

Effects of ovulen-50, diethylnitrosamine and phenobarbital on liver regeneration in female rats

Short term effects of ovulen-50, a combination type oral contraceptive agent and phenobarbital—an established hepatic tumour promoter, were examined in the livers of diethylnitrosamine-initiated and uninitiated female rats. Liver mitotic activity as judged by liver weight, [3H] thymidine incorporation into DNA and levels of DNA, RNA and protein were measured in non-regenerating and regenerating liver. Hepatic γ-glutamyl transpeptidase activity and hepatocyte agglutination with concanavalin A were examined in diethylnitrosamine- and/or phenobarbital-treated rats.The results indicate that diethylnitrosamine or ovulen-50 individually are mitoinhibitory in regenerating liver. Phenobarbital alone has a slight mitostimulatory effects in non-regenerating liver, but no effect on liver regeneration. Administration of ovulen-50 and phenobarbital to diethylnitrosamine initiated rats mitigated the mitoinhibition during regeneration. Contrary to the earlier observation with ovulen-50, neither phenobarbital nor diethylnitrosamine induced hepatocyte agglutination in the presence of concanavalin A. Like ovulen-50, diethylnitrosamine also increased the level of hepatic γ-glutamyl transpeptidase. Phenobarbital produced only insignificant rise and did not substantially exacerbate the effect diethylnitrosamine.The data show that though some of the effects of ovulen-50 resemble those of diethylnitrosamine or phenobarbital, the changes observed may not be related to the neoplastic phenomenon since they were not seen in an initiator-promoter combination regimen.

Metabolism of Pyridoxine in Riboflavin Deficiency

Epithelial lesions of the mouth have been reported to respond to treatment with either riboflavin or pyridoxine. Earlier we had hypothesized that these lesions may be due to cellular deficiency of pyridoxal phosphate (PLP), since the enzyme pyridoxaminephosphate oxidase (PPO) is a flavo protein. Subsequent studies showed that PPO activity is markedly reduced in tissues of riboflavin deficient rat and man1. The in vivo conversion of parenterally administered pyridoxine to PLP was also markedly impaired in riboflavin deficient humans2. Despite this, the concentration of PLP in tissues of riboflavin deficient rat and blood of deficient humans was normal1.