Erythrocyte glutamic-pyruvic transaminase (EGPT) and
glutamic-oxaloacetic transaminase (EGOT) activities reflect
vitamin B₆ status in humans (Baysal, Johnson, and Linkswiler,
1966). Pyridoxal phosphate (PALPO), an active form
of vitamin B₆, serves as the coenzyme for these transaminases.
Compared to other methods of vitamin B₆ assessment,
transaminase measurement has the advantage of...
The relative enrichment of skin sebaceous gland lipids with deuterium-labeled α-tocopherol was compared with plasma enrichment to evaluate the delivery of vitamin E to skin. For the first week of this study, each subject consumed a daily dose of deuterated vitamin E (150 mg of an equimolar mixture of RRR-α-[5-(C²H₃)]-(d₃)...
Published December 1938. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Previous studies have found that smoking may have a negative effect on
vitamin B-6 indices and have demonstrated a possible association between smoking
and depressed plasma pyridoxal-5'-phosphate (PLP) concentration. Individuals with
plasma PLP values below the adequate level of 30 nmoles/L might benefit from
consumption of vitamin B-6 supplements, but...
We compared a kinetic method (KM) and a colorimetric method (CM) for
measuring erythrocyte aspartate aminotransferase (EAST) activity. Twenty-three
healthy college students including 7 men and 16 women, aged from 22 to 40 years,
participated in this study. Vitamin B-6 status was assessed by EAST activity
coefficient (EAST-AC), the ratio...
Trained male cyclists (6 in study 1, 5 in study 2) cycled to exhaustion (EXH) at
75% of VO₂ max twice; once in the non-supplemented (NS) state and once in the vitamin
B-6 (B-6)(20 mg PN) supplemented (S) state. The diet contained 2.3 mg B-6 in study 1
and 1.9...
In rats, sesame lignans increase plasma γ-tocopherol concentrations and inhibit γ-tocopherol degradation to its metabolite γ-carboxyethylhydroxychroman (γ-CEHC). To test if sesame lignan consumption inhibits γ- tocopherol metabolism in humans, muffins prepared with either corn oil (control) or sesame oil and an equimolar mixture of deuterium labeled d6-α- and d2-γ- tocopheryl...
Vitamin C is an essential component of the human diet. Uptake of vitamin C in the cell is regulated by the function of sodium-dependent vitamin C transporters (SVCTs). SVCT1 (encoded by the SLC23A1 gene) is expressed in the colon, liver and kidney, where it plays a vital role in determining...
The effect of vitamin B-6 (B-6) status on plasma fatty acids (FA) levels and lipid
metabolism was investigated in this metabolic study. Eight female subjects were fed for 28
days. For the first 7 days, they were fed a constant diet containing 2.10 mg of B-6. For the
rest of...
Serine transhydroxymethylase (STHM), a pyridoxal 5'-
phosphate requiring enzyme is indirectly involved in
pyrimidine deoxynucleotide metabolism. A decrease in the
activity of this enzyme could lead to altered deoxycytidine
(dC) metabolism. This study was undertaken to determine if
a vitamin B-6 deficiency affects dC metabolism. The effect
of a vitamin...
Thiamine (vitamin B₁) is required by all living organisms for carbohydrate metabolism and synthesis of amino acids. Thiamine deficiency is responsible for several related classes of early life stage mortality disorders in salmonines, including Thiamine Deficiency Complex (TDC) in the Laurentian Great Lakes, Cayuga Syndrome in the Finger Lakes, and...
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Scott A. Heppell
Thiamine (vitamin B1) is required by all living organisms for carbohydrate
The effect of pyridoxine (PN) supplementation on the activities
of erythrocyte alanine aminotransferase (EAlaAT) and aspartate aminotransferase
(EAspAT) was observed in five men, aged 22 to 25 years.
The subjects received a constant diet containing 1.34 mg of vitamin
B-6 Monday through Friday of each week during this five-week study....
The study was designed to indirectly understand muscle
glycogen utilization during prolonged exercise when either
glucose, fructose, or water is ingested. Eight trained
adult males exercised on a cycle ergometer at 58±7% of V02
max for 2 h on 2-4 occasions. At 0 minutes of exercise and
at 30-minute intervals...
This study examined the effect of vitamin B-6 supplementation and exhaustive
submaximal exercise on plasma catecholamine concentrations, and the relationship
between plasma catecholamines and fuel use, heart rate and oxygen consumption. Five
trained men (age= 18-35 years; V0₂max=53 ml 0₂/kg/min.) participated in two controlled
dietary periods that were identical except...
Exercise increases B-vitamin (B6, B12, folate) dependent metabolic reactions, especially those related to energy production and the rebuilding and repairing of muscle tissue. These same B-vitamins are also important in maintaining low blood levels of homocysteine (Hcy), a cardiovascular disease (CVD) risk factor. Hcy levels rise when the metabolism of...
This work sought to characterize a link between Vitamin C and nitroglycerin at the level of enzymatic bioactivation. Before we could proceed, we needed to develop a method that sensitively and selectively identified the product of bioactivation, nitrite. We successfully adapted traditional diaminonaphthalene derivatization with the use of stable isotope...