Jeng M. Hsu

Effect of Thiamine Deficiency on Glutathione Contents of Erythrocytes and Tissues in the Rat

Summary Thiamine deficiency results in decrease in concentration of glutathione in erythrocytes and heart, but an increase in level of glutathione in liver tissue. The exact nature of the alteration of glutathione content is not known. The possible interrelationship of thiamine and glutathione in carbohydrate metabolism is discussed.

Effect of pyridoxine deficiency on the absorption of vitamin B12.

Abstract 1. 1. Pyridoxine deficiency results in an impaired absorption of orally administered vitamin B 12 ∗ . This was demonstrated by urinary and fecal excretion tests, as well as by the measurement of radioactivity in livers and kidneys. The impairment can be fully corrected by subsequent treatment with pyridoxine. 2. 2. Pyridoxine deficiency does not affect the retention of vitamin B 12 ∗ . 3. 3. Deficiencies of thiamine, riboflavine, or pantothenic acid in rats have no influence on the absorption of vitamin B 12 ∗ .

Free amino acids in plasma and tissue of rats born to underfed dams.

Summary Amino acids were determined in plasma, muscle, and liver tissues of adult male rats born of mothers on restricted or nonrestricted diets during pregnancy and lactation. The concentrations of plasma alanine, glutamic acid, glycine, proline, argi-nine, and valine were significantly lower in the progeny of restricted mothers as compared to non-restricted mothers. Similar changes were observed in liver tissues. The concentrations of free amino acids in muscle of the perinatally malnourished progeny, however, did not differ significantly from those of the controls. The differences determined in this study are of special significance in view of the fact that the animals studied had been maintained on an adequate diet since weaning. The demonstrated effect of the maternal diet on the plasma aminogram of the offspring some months later must be considered when interpreting plasma aminograms in studies of malnourished children.

Zinc content in tissues of pyridoxine deficient rats.

Summary Pyridoxine deficiency in rats resulted in a decreased Zn content in the plasma, liver, pancreas, and heart tissues and an increase of Zn-65 uptake in the plasma and liver after an intramuscular injection of radiozinc. A highly significant increase in Zn-65 radioactivity was also observed in the gastrointestinal tract and feces of pyridoxine-deficient rats. This phenomenon appeared to be specific for pyridoxine since deficiency of thiamine or riboflavin did not affect hepatic Zn concentrations.

Urinary Excretion of Radiosulfur Following Taurine-35S Injection in Zinc Deficient Rats

Summary The effect of zinc deficiency on taurine oxidation was studied by comparing the amounts of labeled-35S found in urinary inorganic sulfate and taurine following injection of taurine-35S into zinc-deficient and zinc-supplemented rats. The results show that rats receiving a diet low in zinc excreted significantly more 35S, more 35SO4 2- and taurine-35S than control animals. These findings suggest zinc deficiency enhanced the rate of taurine oxidation. This conclusion is supported by data showing a significant increase in excretion of 24 hr urinary 14C by zinc-deficient rats over zinc-supplemented control rats following injection of taurine-1,2-14C. The radioactivity in the fecal lipid extract was not affected by zinc deficiency, indicating that zinc-deficient rats were capable of forming taurine-bile acid conjugate.

Zinc Deficiency and Epithelial Wound Repair: an Autoradiographic Study of 3H-Thymidine Incorporation

Summary Studies were undertaken to examine the effects of zinc on the repair of the wound in the epithelium. Biopsy specimens obtained from zinc-deficient rats showed a reduced uptake of 3H-thymidine when compared with controls, as shown by liquid scintillation and autoradiography. With wounding, proliferation as indicated by the labeling index increased about twice normal for zinc-supplemented rats, but 3.5 times for zinc-deficient rats. However, despite the increased proliferative rate, repair of wounds in deficient rats was always slower than in zinc-supplemented animals.

Incorporation of Glycine-1-14C into Liver Glutathione in Zinc Deficient Rats

Summary Weanling male rats receiving a diet low in zinc for 2-3 weeks had a significant increase of liver nonprotein SH compounds and glutathione over those fed an adequate zinc diet. Deficiency of this trace element caused an increase in the incorporation rate of glycine-1-14C into liver glutathione moiety, but it had no effect on protein synthesis.

Effect of Deficiencies of Certain B Vitamins and Ascorbic Acid on Absorption of Vitamin B12

of vitamin B12 and methionine or choline in the diet of chicks and rats was observed earlier by Bird,’ 2 and their associates. The interaction between folic acid, vitamin B,2 and ascorbic acid in certain metabolic functions and in the treatment of certain macrocytic anemias in man has been studied extensively.3’4 Observations on an increase of pantothenic acid and coenzyme A (CoA) in the liver of vitamin B12-deficient rats5 and an increase of vitamin B,2 levels in the liver of pantothenic acid deficient rats6 further suggest a reciprocal relationship between these two vitamins. In addition, the relationship between vitamin B12 levels and the deficiency of other vitamins can be seen from the changes in serum and/or liver vitamin B12 activity as listed in Table i.

Further studies on vitamin B 2 deprivation and carbohydrate metabolism

Abstract Vitamin B 12 deprivation creates an elevated DPN/DPNH ratio in rat liver which can be correlated to the magnitude of B 12 depletion. The slow response of the changed DPN/DPNH ratio to vitamin B 12 repletion in deficiency indicates that vitamin B 12 influences coenzyme I secondarily. The elevated DPN/DPNH ratio may be partly attributed to the decrease of activity in the reduced GSH due to B 12 deficiency. In B 12 -deficient rats, an accumulation of blood pyrnvie and lactic acids is observed in postabsorptive state when the body is at rest.

Effect of Pyridoxine Deficiency on Blood Volume Measured by RI131SA and Organ Weights in Rats.

Summary Total blood and plasma volumes measured by use of radioactive iodinated serum albumin (RI131SA) were not altered from normal by chronic pyridoxine deficiency in male and female rats. The average total blood volume as determined by this radioisotopic technic is somewhat higher than values obtained elsewhere by the Evans blue dye method. Organ weight changes have been measured and compared in pyridoxine deficient, desoxypyridoxine treated, and pyridoxine treated rats. Wet and dry weights of the liver, kidney, adrenal, spleen and testes of the deficient animals were greater compared to the pyridoxine treated rats. Administration of the antivitamin, desoxypyridoxine, to pyridoxine deficient rats not only increased the apparent hypertrophy of these organs, but also accentuated the marked atrophy of thymus associated with pyridoxine deficiency.