Neopterin is synthesised from GTP via GTP cyclohydrolase
Sauna therapy can act via two distinct mechanisms to raise the levels of BH4, acting in both cases by raising the levels of the enzyme GTP cyclohydrolase I (GPCH), the first and rate-limiting enzyme in the de novo synthesis pathway for BH4.
GTP cyclohydrolase I (GPCH), in lymphocytes isolated from blood, was assayed by the method of Werner et al.
3] Human genes: CYP2C19, cytochrome P450, family 2, subfamily C, polypepetide 19; GCH1, GTP cyclohydrolase
1; TH, tyrosine hydroxylase; SPR, sepiapterin reductase (7,8-dihydrobiopterin:NADP+ oxidoreductase); PML, promyelocytic leukemia; RARA, retinoic acid receptor, alpha.
The first step of the plant pterin branch is catalyzed by an unusual GTP cyclohydrolase
I (GTPCHI, Fig.
The Punch locus of Drosophila encodes GTP cyclohydrolase
I, a multimeric enzyme that catalyzes the first step in pterin biosynthesis.
These diseases include: GTP Cyclohydrolase
I Deficiency (dopa responsive dystonia) and Tyrosine Hydroxylase Deficiency (both currently treatable), Aromatic L Amino Acid Decarboxylase Deficiency, and Succinic Semialdehyde Dehydrogenase (SSADH) Deficiency.
sauna therapy Acts to increase BH4 Trials availabiity; mechanism published on via increased synthesis MCS, FM and of GTP cyclohydrolase
An exception is found in dominantly inherited GTP cyclohydrolase
deficiency (doparesponsive dystonia) (15); in this disorder, it appears that the major impact is on the dopaminergic system, as an isolated decrease in HVA is observed (16).
4% of alleles in the study population) of the GTP cyclohydrolase
gene (dopa-responsive dystonia, GCH1) and lower degrees of persistent pain after back surgery.
A haplotype in the GTP cyclohydrolase
1 (dopa-responsive dystonia) gene (GCH1)  [(1), Fig.
Mutations in the GTP cyclohydrolase
I and 6-pyruvoyl-tetrahydropterin synthase genes.