Pyridoxine
The 4-methanol form of VITAMIN B 6 which is converted to PYRIDOXAL PHOSPHATE which is a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. Although pyridoxine and Vitamin B 6 are still frequently used as synonyms, especially by medical researchers, this practice is erroneous and sometimes misleading (EE Snell; Ann NY Acad Sci, vol 585 pg 1, 1990).
Pyridoxaminephosphate Oxidase
An enzyme catalyzing the deamination of pyridoxaminephosphate to pyridoxal phosphate. It is a flavoprotein that also oxidizes pyridoxine-5-phosphate and pyridoxine. EC 1.4.3.5.
Vitamin B 6 Deficiency
A nutritional condition produced by a deficiency of VITAMIN B 6 in the diet, characterized by dermatitis, glossitis, cheilosis, and stomatitis. Marked deficiency causes irritability, weakness, depression, dizziness, peripheral neuropathy, and seizures. In infants and children typical manifestations are diarrhea, anemia, and seizures. Deficiency can be caused by certain medications, such as isoniazid.
Pyridoxal Phosphate
This is the active form of VITAMIN B 6 serving as a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. During transamination of amino acids, pyridoxal phosphate is transiently converted into pyridoxamine phosphate (PYRIDOXAMINE).
Pyridoxal
The 4-carboxyaldehyde form of VITAMIN B 6 which is converted to PYRIDOXAL PHOSPHATE which is a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid.
Pyridoxal Kinase
An enzyme that catalyzes reversibly the phosphorylation of pyridoxal in the presence of ATP with the formation of pyridoxal 5-phosphate and ADP. Pyridoxine, pyridoxamine and various derivatives can also act as acceptors. EC 2.7.1.35.
Pyridoxamine
The 4-aminomethyl form of VITAMIN B 6. During transamination of amino acids, PYRIDOXAL PHOSPHATE is transiently converted into pyridoxamine phosphate.
Doxylamine
Histamine H1 antagonist with pronounced sedative properties. It is used in allergies and as an antitussive, antiemetic, and hypnotic. Doxylamine has also been administered in veterinary applications and was formerly used in PARKINSONISM.
Vitamin B 6
VITAMIN B 6 refers to several PICOLINES (especially PYRIDOXINE; PYRIDOXAL; & PYRIDOXAMINE) that are efficiently converted by the body to PYRIDOXAL PHOSPHATE which is a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, and aminolevulinic acid. During transamination of amino acids, pyridoxal phosphate is transiently converted into PYRIDOXAMINE phosphate. Although pyridoxine and Vitamin B 6 are still frequently used as synonyms, especially by medical researchers, this practice is erroneous and sometimes misleading (EE Snell; Ann NY Acad Sci, vol 585 pg 1, 1990). Most of vitamin B6 is eventually degraded to PYRIDOXIC ACID and excreted in the urine.
Pyridoxic Acid
The catabolic product of most of VITAMIN B 6; (PYRIDOXINE; PYRIDOXAL; and PYRIDOXAMINE) which is excreted in the urine.
Homocystinuria
Autosomal recessive inborn error of methionine metabolism usually caused by a deficiency of CYSTATHIONINE BETA-SYNTHASE and associated with elevations of homocysteine in plasma and urine. Clinical features include a tall slender habitus, SCOLIOSIS, arachnodactyly, MUSCLE WEAKNESS, genu varus, thin blond hair, malar flush, lens dislocations, an increased incidence of MENTAL RETARDATION, and a tendency to develop fibrosis of arteries, frequently complicated by CEREBROVASCULAR ACCIDENTS and MYOCARDIAL INFARCTION. (From Adams et al., Principles of Neurology, 6th ed, p979)
Glucosides
Xanthurenates
Xanthurenic acid and its salts, formed as byproducts during the metabolism of tryptophan, are collectively referred to as xanthurenates, which can accumulate in conditions like hyperphenylalaninemia and may contribute to oxidative stress and cellular damage.
Riboflavin
Nutritional factor found in milk, eggs, malted barley, liver, kidney, heart, and leafy vegetables. The richest natural source is yeast. It occurs in the free form only in the retina of the eye, in whey, and in urine; its principal forms in tissues and cells are as FLAVIN MONONUCLEOTIDE and FLAVIN-ADENINE DINUCLEOTIDE.