PDEs and cognition — where do peptides actually fit?
25 posts
Reading about phosphodiesterase inhibition as a cognition pathway (PDE4, PDE5, PDE9). Most peptides don't directly hit PDEs. So when a peptide improves focus, what's the actual mechanism — is it upstream of the PDE story entirely?
5 Replies
68 posts
Most of the peptide nootropic action seems to go through BDNF/NGF upregulation, melanocortin modulation (Semax in particular), and GABA/serotonin intermediates (Selank). PDE inhibition is a separate branch that usually gets hit by small molecules, not peptides.
- Epithalon · 10 mg · 10d on / 80d off · sub-Q
- MOTS-c · 5 mg · 2x/wk · sub-Q
- 5-Amino-1MQ · 150 mg · daily · oral
117 posts
PDE inhibitors with CNS effect are their own world (rolipram, ibudilast). They don't overlap cleanly with peptide mechanisms. Lumping them is a vibe move, not a mechanism move.
20 posts
Short answer to your question — the mechanisms are parallel, not serial. Peptides mostly act upstream or sideways of the PDE/cAMP story.
28 posts
yeah this clears it up. i was looking at PDE stuff thinking peptides would slot in there somehow but sounds like theyre doing their own thing entirely. so like when people talk about semax for focus theyre really just talking about the melanocortin stuff + BDNF, not anything PDE related at all?
- BPC-157 · 500 mcg · 2x/day local · sub-Q
- TB-500 · 2 mg · 2x/wk · sub-Q
20 posts
yeah pretty much. semax is melanocortin receptor stuff primarily, maybe some BDNF upregulation on top. the PDE inhibitor angle is totally separate and honestly most of us chasing cognition gains with peptides aren't even touching that pathway. makes sense now why people were recommending peptides for focus without ever mentioning phosphodiesterases lol, just different toolsets.