P5P/PLP

タイトルまたは説明

Pyridoxal**-phosphates actions mainly involve the metabolism of amino acids and other nitrogen compounds:

1)     In the liver, pyridoxal**-phosphate is essential for glucose production from amino acids through its role as a coenzyme for the transaminase enzymes. Pyridoxal**-phosphate is also needed in the liver and muscles to access stored glycogen for glucose production, and to synthesize niacin from the amino acid tryptophan.

2)     In red blood cells, pyridoxal**-phosphate is needed for hemoglobin synthesis, and regulation of oxygen affinity. Moreover, cell receptivity to steroid hormones is influenced by pyridoxal**-phosphate.

3)     In the nervous system, pyridoxal**-phosphate is needed for synthesis of several neurotransmitters, including serotonin (from tryptophan), taurine, dopamine, norepinephrine, histamine, and gamma- aminobutyric acid (GABA). Many experimental and clinical observations support the fact that dietary vitamin B 6 is required to maintain normal nervous system function.

4)     Along with vitamin B *2 and folic acid, pyridoxal**-phosphate is involved in single carbon metabolism, and is necessary for maintaining normal plasma homocysteine levels. Elevated plasma homocysteine may be an independent risk factor for the development of cardiovascular disease. Also, due to its involvement in single carbon metabolism, pyridoxal**-phosphate assists in maintaining normal immune function.