Cofactor tetrahydrobiopterin (BH4)

[Coolio]

Does anyone here know if ingesting tetrahydrobiopterin would have any kind of stimulant/antidepressant effects in a depressed individual? It's an enzyme cofactor that tryptophan hydroxylase, phenylalanine hydroxlyase, and tyrosine hydroxlyase use in the production of serotonin, tyrosine, and L-dopa. Would it be useful post-MDMA to combat the serotonin depletion aftereffects, as MDMA is a tryptophan hydroxylase inhibitor?

I'm also curious about about sapropterin (Phenoptin), a drug in clinical trials that is called a 'synthetic form of 6R-BH4'. Does this mean it's actually tetrahydrobiopterin, or a synthetic analog?

The main question I have is, would oral ingestion of this cofactor help boost catecholamine levels in depressed individuals for whom something like 5-HTP is mildly effective or completely ineffective?

 

[BilZ0r]

Yes, I imagine it will increase serotonin release, though to what extent, I have no idea. 5-HTP could be able to produce serotonin levels far apart what BH4 does.

Phenoptin is an anlogue

 

[Coolio]

Further research on this subject leads me to wonder why vitamin B6 isn't ever mentioned in any discussion of 5-HTP supplementation? Would the decarboxlyation of 5-HTP to serotonin be rate-limited by B6?

I'm looking at this from the point of view of depression, not of optimal human neurochemistry. Could enzymatic cofactors be more limiting than the amount of enzymes themselves?

If not... is there any way to stimulate the production of tryptophan hydroxlyase and aromatic L-amino acid decarboxylase?

 

[raybeez]

Further research on this subject leads me to wonder why vitamin B6 isn't ever mentioned in any discussion of 5-HTP supplementation? Would the decarboxlyation of 5-HTP to serotonin be rate-limited by B6?

I'm looking at this from the point of view of depression, not of optimal human neurochemistry. Could enzymatic cofactors be more limiting than the amount of enzymes themselves?

If not... is there any way to stimulate the production of tryptophan hydroxlyase and aromatic L-amino acid decarboxylase?

Where I live, 5-HTP formulations sold at health food stores almost always include vitamin B6 in the pill.

 

[Coolio]

raybeez ah interesting. I've never looked at a bottle of 5-HTP supplements, I've always purchased 5-HTP isolated from plant material.

 

[BilZ0r]

^ All 5-HTP comes from plant sources, "supplements" or otherwise.
You don't want to take B6 with 5-HTP, because if it works, it will increase 5-HTP-->5-HT conversion in the gut and blood, not in the brain.

 

[nanobrain]

^beat me to it. the formuators combining the B6 w/the 5HTP are doing you a disfavor.