Colostrinin vs N-Acetyl Selank
A neutral, side-by-side comparison of two nootropic & cognitive peptides — their mechanisms, dosing ranges, administration routes, side effects, and research evidence. For research and educational purposes only.
Colostrinin
Proline-rich polypeptide complex isolated from ovine (sheep) colostrum. Originally researched as an Alzheimer's disease modulator, colostrinin has shown ability to stabilize cognitive function and reduce progression in mild-to-moderate Alzheimer's patients in double-blind trials. Also studied for immune modulation and anti-aging properties via cytokine balance normalization.
Full profileN-Acetyl Selank
Acetylated variant of Selank with enhanced stability and bioavailability. The N-acetyl modification protects the peptide from rapid enzymatic degradation, extending its active half-life relative to standard Selank. Provides anxiolytic, nootropic, and immunomodulatory effects comparable to or exceeding standard Selank with potentially greater duration from each dose.
Full profile| Colostrinin | N-Acetyl Selank | |
|---|---|---|
| Category | Nootropic & Cognitive | Nootropic & Cognitive |
| Also known as | PRP (proline-rich polypeptide), ND, colostrum neuropeptide, CLN, ovine proline-rich polypeptide | Selank-A, N-Ac-Selank, acetylated selank, N-acetyl selank |
| Evidence | Research-stage | Research-stage |
| Dosing range | 100mcg–400mcg mcg, sublingual, on a 3 days on / 3 days off cycle | 100mcg–500mcg mcg, 1–2x daily intranasal |
| Administration | Sublingual tablet/drop | Intranasal spray, Subcutaneous injection |
| Key side effects | Generally well-tolerated, Mild GI discomfort, Rare hypersensitivity (relevant for dairy protein sensitivity), Mild fatigue (initial days) | Mild sedation (acute), Fatigue, Headache (rare), Nasal irritation (intranasal route) |
| Cited sources | 2 references | 2 references |
Key differences
- Administration: Colostrinin — Sublingual tablet/drop; N-Acetyl Selank — Intranasal spray, Subcutaneous injection.
- Frequency: Colostrinin is typically sublingual, on a 3 days on / 3 days off cycle; N-Acetyl Selank is 1–2x daily intranasal.
How each works
Colostrinin
Colostrinin modulates dendritic cell maturation and shifts cytokine balance toward anti-inflammatory patterns (reduced IL-6, TNF-α; increased IL-10). In neurological models, it reduces amyloid-β aggregation, decreases oxidative stress, and upregulates NGF while modulating the HPA axis stress response. A Polish double-blind trial showed statistically significant cognitive stabilization in mild-to-moderate AD patients over 15 weeks.
N-Acetyl Selank
N-Acetyl Selank shares Selank's core mechanism — BDNF/NGF upregulation, enkephalinase inhibition, and GABA-A receptor complex modulation — with improved metabolic stability from the N-terminal acetyl group. The acetyl modification protects against aminopeptidase N and angiotensin-converting enzyme cleavage, extending the peptide's active residence time in neural tissue after intranasal administration.
This comparison aggregates public research and structured profile data for informational purposes only. It is not medical advice and does not recommend either compound for human use. Consult a qualified healthcare provider before considering any peptide.