Leucocyte Ascorbic Acid Levels and Vitamin C Intake in Older People

Leucocyte ascorbic acid (L.A.A.) levels and vitamin C intake were measured in a random sample of men and women aged 62-94 years. L.A.A. distributions are positively skewed but log normal. L.A.A. mean values show no age difference in men but are significantly lower in older women. The mean value for all women (23·88μg/10⁸ cells) is significantly higher than that for all men (18·11 μg/10⁸ cells). L.A.A. values are significantly higher in both sexes in the six months July to December. Vitamin C intake distributions are positively skewed but not improved by log transformation. No significant age or sex differences were found except that a significantly greater proportion of men over than of those under 70 years have intakes less than 30 mg daily. Mean intake is significantly higher in men but not in women in the six months April to September, though in both sexes a significantly greater proportion have intakes less than 30 mg daily in October to March compared with April to September. Fifty per cent. of men and 58% of women have intakes less than 30 mg daily, 23·6% of men and 28·1% of women have intakes less than 20 mg daily, and 4·7% of men and 3% of women have intakes less than 10 mg daily. These percentages increase during the winter. A moderate correlation is present between vitamin C intake and L.A.A. level. L.A.A. levels increase in parallel with but lag behind seasonal increases in vitamin C intake.     

Urinary Hydroxyproline in the Elderly with Low Leucocyte Ascorbic Acid Levels

Fourteen elderly patients aged 58 to 91 with varying leucocyte ascorbic acid levels had urinary hydroxyproline/creatinine ratios measured before, during, and after treatment with ascorbic acid 1 g. daily for six days. The ratio increased during treatment in those patients whose initial ascorbic acid levels were below 15μg./10⁸ white blood cells. It is suggested that collagen metabolism may be impaired in these patients, and that all such patients should receive ascorbic acid supplements.     

Ascorbic Acid Levels in Avian Tissues and Its Metabolic Significance

The site of localization and concentration of ascorbic acid (AA) in a number of tissues of the pigeon were studied by a modified histochemical method coupled with cytophotoelectrometric determinations. It was evident from the data that significant variations were found in AA concentrations of different tissues of the pigeon. The brain possessed the highest content of AA/cell. The liver, ovary, pancreatic acini, kidney, adrenal and testis followed in order, whereas, the pancreatic islet region was the poorest in AA. On the basis of the synchronization of the high AA content of these tissues with their well known high level of metabolic activity, it is suggested that AA participates in the metabolic turnover by serving as an electron donor via the formation of its free radical. Considering the fact that these organs are very rich in ascorbic acid, there is also a possibility for the biosynthesis of AA in tissues like the liver and kidney of the pigeon as in other bird species. The need for further work in this direction is stressed.     

Enterococcus faecalis Grows on Ascorbic Acid

We show that Enterococcus faecalis can utilize ascorbate for fermentative growth. In chemically defined media, growth yield was limited by the supply of amino acids, and the cells showed a much higher demand for amino acids than when they were grown on glucose.     

Effect of Vagotomy on Ascorbic Acid Nutrition in Patients with Peptic Ulcer

In 33 patients undergoing surgery for peptic ulcer it was found that both the dietary and the leucocyte ascorbic acid levels fell below the accepted normal values. Although after vagotomy the dietary intake improved dramatically, this was accompanied by only a small rise in leucocyte ascorbic acid levels. Evidence has been presented that the reduction in gastric acid output after vagotomy might be responsible for this paradox.     

Molecular Complexes of Tetracycline Acid Salts

A series of studies on the crystalline molecular complexes of tetracycline groups have been carried out in this laboratory, and the present paper deals with the compositions of the oxalic acid complexes of various tetracycline acid salts, which were examined by X-ray powder diffraction methods, infrared spectra, and chemical analyses. Insertions of salt anions and crystal water in the crystal lattice of the complexes, and the important role of the latter for crystallization are indicated.     

Molecular Complexes of Tetracycline Acid Salts

The different behavior of 5-hydroxytetracycline from tetracycline on the complex formation in spite of the similarity of both complexes in X-ray diffraction patterns, and the difficulty of complex formation of 7-chlorotetracycline, are suggestive of the hindrance effect of 5-hydroxy or 7-chioro group for the formation of complex lattice. Applying the above properties, tetracycline is separated from 5-hydroxytetracycline as the sulfate-succinimide complex, and tetracycline and 5-hydroxytetracycline are separated from 7-chlorotetracycline as their oxalic acid, sulfate-oxalic acid, sulfate-hydantoin and sulfate-succinimide complexes. 7-Chlorotetracycline is recovered as the hydrogenmaleate or the hydrochloride from the mother liquor.     

Effects of Iron Overload on Ascorbic Acid Metabolism

Studies of the ascorbic acid status in two subjects with idiopathic haemochromatosis and in 12 with transfusional siderosis showed that all had decreased levels of white cell ascorbic acid. The urinary excretion of ascorbic acid was also diminished in those subjects in whom such measurements were made. The administration of ascorbic acid was followed by only a small rise in the urinary ascorbic acid output, while the oxalic acid levels (measured in two subjects) showed a significant rise. These findings resemble those described in siderotic Bantu, and support the thesis that increased iron stores lead to irreversible oxidation of some of the available ascorbic acid.     

High Levels of Ascorbic Acid, Not Glutathione, in the CNS of Anoxia-Tolerant Reptiles Contrasted with Levels in Anoxia-Intolerant Species

Abstract: Ascorbic acid and glutathione (GSH) are antioxidants and free radical scavengers that provide the first line of defense against oxidative damage in the CNS. Using HPLC with electrochemical detection, we determined tissue contents of these antioxidants in brain and spinal cord in species with varying abilities to tolerate anoxia, including anoxia-tolerant pond and box turtles, moderately tolerant garter snakes, anoxia-intolerant clawed frogs (Xenopus laevis), and intolerant Long-Evans hooded rats. These data were compared with ascorbate and GSH levels in selected regions of guinea pig CNS, human cortex, and values from the literature. Ascorbate levels in turtles were typically 100% higher than those in rat. Cortex, olfactory bulb, and dorsal ventricular ridge had the highest content in turtle, 5–6 µmol g^?1 of tissue wet weight, which was twice that in rat cortex (2.82 ± 0.05 µmol g^?1) and threefold greater than in guinea pig cortex (1.71 ± 0.03 µmol g^?1). Regionally distinct levels (2–4 µmol g^?1) were found in turtle cerebellum, optic lobe, brainstem, and spinal cord, with a decreasing anterior-to-posterior gradient. Ascorbate was lowest in white matter (optic nerve) in each species. Snake cortex and brainstem had significantly higher ascorbate levels than in rat or guinea pig, although other regions had comparable or lower levels. Frog ascorbate was generally in an intermediate range between that in rat and guinea pig. In contrast to ascorbate, GSH levels in anoxia-tolerant turtles, 2–3 µmol g^?1 of tissue wet weight, were similar to those in mammalian or amphibian brain, with no consistent pattern associated with anoxia tolerance. GSH levels in pond turtle CNS were significantly higher (by 10–20%) than in rat for several regions but were generally lower than in guinea pig or frog. GSH in box turtle and snake CNS were the same or lower than in rat or guinea pig. The distribution GSH in the CNS also had a decreasing anterior-to-posterior gradient but with less variability than ascorbate; levels were similar in optic nerve, brainstem, and spinal cord. The paradoxically high levels of ascorbate in turtle brain, which has a lower rate of oxidative metabolism than mammalian, suggest that ascorbate is an essential cerebral antioxidant. High levels may have evolved to protect cells from oxidative damage when aerobic metabolism resumes after a hypoxic dive.     

Ascorbic Acid in Neural Tissues

Abstract: Large amounts of ascorbic acid were readily removed from neural tissue by washing with warmed saline solutions. In areas where the original level was highest, such as cortex and cerebellum, a higher percentage was removed than from areas of lower concentration, such as pons-medulla. The residual level in both types of tissue was similar. During scurvy, the ascorbic acid retained in the guinea pig brain is more readily removed by washing than is that of the normal brain.