Humanin vs SNAP-8 (Acetyl Octapeptide-3)
A neutral, side-by-side comparison of two anti-aging & longevity peptides — their mechanisms, dosing ranges, administration routes, side effects, and research evidence. For research and educational purposes only.
Humanin
Humanin is a 21-amino acid mitochondrial-derived peptide (MDP) encoded within the 16S ribosomal RNA gene of the mitochondrial genome — discovered in 2001 through a screen for neuroprotective factors in Alzheimer's disease. It is the founding member of a new class of peptide hormones encoded by mitochondria, not nuclear DNA. Circulating humanin levels decline sharply with age and are inversely correlated with cardiovascular disease risk, insulin resistance, and cognitive decline.
Full profileSNAP-8 (Acetyl Octapeptide-3)
8-amino acid cosmetic peptide active (Acetyl Octapeptide-3) that competes with SNARE complex proteins to reduce neuromuscular signal transmission in facial expression muscles. An extended, more potent version of Argireline (Acetyl Hexapeptide-3). Clinical studies show 26–63% reduction in expression wrinkle depth with twice-daily application, positioning it as a topical botulinum toxin alternative.
Full profile| Humanin | SNAP-8 (Acetyl Octapeptide-3) | |
|---|---|---|
| Category | Anti-Aging & Longevity | Anti-Aging & Longevity |
| Also known as | HN, HNG (Gly14-Humanin — more potent analog), Mitochondrial-derived peptide | Leuphasyl, Acetyl Octapeptide-3, SNAP-8 peptide, Argireline extension, Acetyl Glutamyl Heptapeptide-3 |
| Evidence | Research-stage | Research-stage |
| Dosing range | 100mcg–2mg mcg, Daily or 3–5x weekly | 1%–10% %, twice daily topical application |
| Administration | Subcutaneous injection, Intranasal (for CNS applications), Intravenous (clinical studies) | Topical (serum/cream) |
| Key side effects | Generally well-tolerated in animal studies, No significant adverse effects reported at research doses, Potential interaction with GH/IGF-1 axis (IGF-1 suppresses humanin production), Long-term human safety data limited | Very well-tolerated, Rare mild skin irritation or redness, No systemic absorption at cosmetic concentrations, No paralysis risk (partial SNARE competition only) |
| Cited sources | 3 references | 2 references |
Key differences
- Administration: Humanin — Subcutaneous injection, Intranasal (for CNS applications), Intravenous (clinical studies); SNAP-8 (Acetyl Octapeptide-3) — Topical (serum/cream).
- Dosing units differ: Humanin is dosed in mcg, SNAP-8 (Acetyl Octapeptide-3) in % — they operate at different scales.
- Frequency: Humanin is typically Daily or 3–5x weekly; SNAP-8 (Acetyl Octapeptide-3) is twice daily topical application.
- Research depth: this profile cites 3 sources for Humanin vs 2 for SNAP-8 (Acetyl Octapeptide-3).
How each works
Humanin
Humanin acts through multiple receptors (CNTFR/WSX-1/gp130 trimeric complex and FPRL1) to exert neuroprotection, cardioprotection, and metabolic effects. Key findings: humanin inhibits neuronal apoptosis in Alzheimer's disease models by blocking IGFBP-3 death signaling, reduces cardiovascular disease markers in clinical studies, improves insulin sensitivity in diabetic models, and reduces oxidative stress. IGF-1 downregulates humanin production — individuals on GH/IGF-1 therapies may have suppressed endogenous humanin. Centenarians have elevated humanin levels compared to age-matched controls.
SNAP-8 (Acetyl Octapeptide-3)
SNAP-8 mimics the N-terminal domain of SNAP-25, competing for SNARE complex assembly required for acetylcholine vesicle fusion at the neuromuscular junction. This partial inhibition reduces muscle contraction intensity without complete paralysis. Clinical studies demonstrate statistically significant reductions in crow's feet and forehead line depth after 28 days of use at 5–10% concentration.
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.