Something quite interesting turned up. Semax and selank did nothing for me, and I took them intranasally since that route gets recommended almost universally as the optimal one. I'm not saying it doesn't work for plenty of others — but in my case it never did, and both delivery factors and individual biology can interfere.
Digging into it, I found that aminopeptidase enzymes in the nasal cavity degrade it extremely fast, so frequently just a minuscule quantity gets through beforehand — the study measured a mere 0.093% and merely 80% of that remains intact Semax. Within minutes nasally, Semax gets cleaved into PGP (a tripeptide metabolite).
excerpt from https://pubmed.ncbi.nlm.nih.gov/16523722/ :
So I switched to pinning semax subq, and results are actually showing up now! Sure, crossing the blood brain barrier is an obstacle, but it appears to be a smaller obstacle than whatever my nose was doing.
Figured I'd pass along this research in case anyone's curious — if intranasal gives you nothing, give subq a shot. Worth noting the NA (amidated) semax versions resist breakdown better, so they likely don't share this issue (mine is plain semax).
Selank appears to degrade along similar lines according to studies:
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[Evenly tritium-labeled peptides and their in vivo and in vitro biodegradation] - PubMed
Biologically active peptides evenly labeled with tritium were used for studying the in vitro and in vivo biodegradation of the peptides. Tritium-labeled peptides with a specific radioactivity of 50-150 Ci/mmol were obtained by high temperature solid phase catalytic isotope exchange (HSCIE) with...
Image unavailable
pubmed.ncbi.nlm.nih.gov
Digging into it, I found that aminopeptidase enzymes in the nasal cavity degrade it extremely fast, so frequently just a minuscule quantity gets through beforehand — the study measured a mere 0.093% and merely 80% of that remains intact Semax. Within minutes nasally, Semax gets cleaved into PGP (a tripeptide metabolite).
excerpt from https://pubmed.ncbi.nlm.nih.gov/16523722/ :
It was demonstrated that 0.093% of the total introduced radioactivity per gram can be found in the rat brain 2 min after the administration, 80% of this radioactivity belonged to Semax, and the rest, to its metabolites. The peptide undergoes rapid enzymatic degradation
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So I switched to pinning semax subq, and results are actually showing up now! Sure, crossing the blood brain barrier is an obstacle, but it appears to be a smaller obstacle than whatever my nose was doing.
Figured I'd pass along this research in case anyone's curious — if intranasal gives you nothing, give subq a shot. Worth noting the NA (amidated) semax versions resist breakdown better, so they likely don't share this issue (mine is plain semax).
Selank appears to degrade along similar lines according to studies:
Image unavailable
[Evenly tritium-labeled peptides and their in vivo and in vitro biodegradation] - PubMed
Biologically active peptides evenly labeled with tritium were used for studying the in vitro and in vivo biodegradation of the peptides. Tritium-labeled peptides with a specific radioactivity of 50-150 Ci/mmol were obtained by high temperature solid phase catalytic isotope exchange (HSCIE) with...
Image unavailable
pubmed.ncbi.nlm.nih.gov