Humanin vs LL-37 (Cathelicidin)

Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.

HumaninLL-37 (Cathelicidin)
CategoryPeptidesPeptides
Standard DoseResearch indicates dosing remains experimental. Animal studies use 1-10 mcg/day equivalents. Human protocols are not established.Research indicates 50-100 mcg daily via subcutaneous injection for immune support.
TimingNo established timing protocol. Morning dosing suggested for neuroprotective applications.Morning administration preferred for immune support. Topical application directly to wound sites.
Cycle DurationExperimental — no established cycle lengths.4-8 week cycles. Short-term use preferred due to limited long-term safety data.
Evidence Levelanimal_plus_anecdotalanimal_plus_anecdotal
A

Humanin

Peptides

Mechanism

Humanin is a 24-amino acid mitochondrial-derived peptide encoded by the 16S rRNA gene of mitochondrial DNA. It binds IGFBP-3 with high affinity (via Phe-6), interfering with IGFBP-3 binding to importin-beta and suppressing IGFBP-3-mediated apoptosis. It also inhibits the pro-apoptotic protein Bax (Bcl-2 family), preventing mitochondrial outer membrane permeabilization and intrinsic apoptosis. Humanin and IGFBP-3 synergistically protect neurons from amyloid-beta-induced apoptosis, and it activates the STAT3 and ERK1/2 pathways for cytoprotection.

Standard Dosing

Research indicates dosing remains experimental. Animal studies use 1-10 mcg/day equivalents. Human protocols are not established.

Timing

No established timing protocol. Morning dosing suggested for neuroprotective applications.

Cycle Duration

Experimental — no established cycle lengths.

Side Effects

  • Limited data on side effects in humans
  • Theoretical: interference with normal apoptotic processes

Contraindications

  • Active cancer (anti-apoptotic effects could support tumor survival)
  • Pregnancy and breastfeeding

Best Stacking Partners

MOTS-cEpitalonSS-31

Mechanism

LL-37 is a 37-residue amphipathic helical antimicrobial peptide, the only human cathelicidin, that kills bacteria by forming tetrameric channels that perforate cytoplasmic membranes. Beyond direct antimicrobial activity, it modulates innate immunity through formyl-peptide receptor 2 (FPR2), induces chemotaxis of neutrophils and monocytes, upregulates CXCR4 and IL-8, and neutralizes bacterial endotoxins (LPS). It also promotes wound healing through keratinocyte migration and angiogenesis.

Standard Dosing

Research indicates 50-100 mcg daily via subcutaneous injection for immune support.

Timing

Morning administration preferred for immune support. Topical application directly to wound sites.

Cycle Duration

4-8 week cycles. Short-term use preferred due to limited long-term safety data.

Side Effects

  • Injection site pain and redness
  • Localized inflammation
  • Potential mast cell activation

Contraindications

  • Active autoimmune conditions (particularly lupus — LL-37 is implicated in SLE pathophysiology)
  • Pregnancy and breastfeeding
  • Psoriasis (may exacerbate)

Best Stacking Partners

KPVThymosin Alpha-1BPC-157

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