Phenoptin
Phenoptin - General Information
Phenoptin or BH4 is a cofactor in the synthesis of nitric oxide. It is also essential in the conversion of phenylalanine to tyrosine by the enzyme phenylalanine-4-hydroxylase; the conversion of tyrosine to L-dopa by the enzyme tyrosine hydroxylase; and conversion of tryptophan to 5-hydroxytryptophan via tryptophan hydroxylase. [Wikipedia]
Pharmacology of Phenoptin
Phenoptin (BH4) is used to convert several amino acids, including phenylalanine, to other essential molecules in the body including neurotransmitters. Phenoptin deficiency can be caused by mutations in GTP cyclohydrolase 1 (GCH1), 6-pyruvoyl-tetrahydropterin synthase/dimerization cofactor of hepatocyte nuclear factor 1 alpha (PCBD1), 6-pyruvoyltetrahydropterin synthase (PTS), and quinoid dihydropteridine reductase (QDPR) genes. These genes make the enzymes that are critical for producing and recycling tetrahydrobiopterin. If one of the enzymes fails to function correctly because of a gene mutation, little or no tetrahydrobiopterin is produced. As a result, phenylalanine from the diet builds up in the bloodstream and other tissues and can damage nerve cells in the brain. High levels of phenylalanine can result in signs and symptoms ranging from temporary low muscle tone to mental retardation, movement disorders, difficulty swallowing, seizures, behavioral problems, progressive problems with development, and an inability to control body temperature.
Additional information about Phenoptin
Phenoptin Indication: For the treatment of tetrahydrobiopterin (BH4) deficiency.
Mechanism Of Action: Phenoptin (BH4) is a natural co-factor or co-enzyme for phenylalanine-4-hydroxylase (PAH), tyrosine-3-hydroxylase, and tryptophan-5-hydroxylase. Phenoptin is also a natural co-factor for nitrate oxide synthase. Therefore BH4 is required for the conversion of phenylalanine to tyrosine, for the production of epinephrine (adrenaline) and the synthesis of the monoamine neuro-transmitters, serotonin, dopamine, and norepinephrine (noradrenaline). It is also involved in apoptosis and other cellular events mediated by nitric oxide production. As a coenzyme, BH4 reacts with molecular oxygen to form an active oxygen intermediate that can hydroxylate substrates. In the hydroxylation process, the co-enzyme loses two electrons and is regenerated in vivo in an NADH-dependent reaction. As a co-factor for PAH, tetrahydrobiopterin allows the conversion of phenylalanine to tyrosine and reduces the level of phenylalanine in the bloodstream, thereby reducing the toxic effects of of this amino acid. Normal serum concentrations of phenylalanine are 100 micomolar, while elevated (toxic) levels are typically >1200 micromolar. Individuals with a deficiency in tetrahydrobiopterin are not able to efficiently convert phenylalanine to tyrosine. The excess levels provided by tetrahydrobiopterin supplementation help improve enzyme efficiency. As a co-factor for tyrosine hydroxylase, BH4 facilitates the conversion of tyrosine to L-dopa while as a co-factor for tryptophan hydroxylase, BH4 allows the conversion of tryptophan to 5-hydroxytryptophan, which is then converted to serotonin.
Drug Interactions: Not Available
Food Interactions: Not Available
Generic Name: Tetrahydrobiopterin
Synonyms: 5,6,7,8 Tetrahydrobiopterin; BH4
Drug Category: Dietary supplement; Cofactor
Drug Type: Small Molecule; Approved; Investigational
Other Brand Names containing Tetrahydrobiopterin: Dapropterin; Sapropterin; Kuvan; Phenoptin;
Absorption: Not Available
Toxicity (Overdose): Not Available
Protein Binding: Not Available
Biotransformation: Not Available
Half Life: Not Available
Dosage Forms of Phenoptin: Not Available
Chemical IUPAC Name: 2-amino-6-(1,2-dihydroxypropyl)-5,6,7,8-tetrahydro-1H-pteridin-4-one
Chemical Formula: C9H15N5O3
Tetrahydrobiopterin on Wikipedia: https://en.wikipedia.org/wiki/Tetrahydrobiopterin
Organisms Affected: Humans and other mammals
