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Specimen Atlas of Research Peptides81 plates · MIT
Side-by-side · Research reference

DSIPvsLL-37

Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.

AHuman-MechanisticAUTO-DRAFTED8/36 cited
BHuman-MechanisticHUMAN-REVIEWED15/35 cited
DSIP
Sleep modulator · Anti-stress
100–200 mcgPer doseSchneider 1986
HumanMechanisticSchneider 1986
HoursHalf-life (est)
SQ · Pre-sleep · Daily during cycle
LL-37
Cathelicidin · Human AMP
Broad-spectrumAntimicrobial activity
Membrane disruptionPrimary mechanismLu 2026He 2026
Innate immunityHost defense rolePinheiro 2026Zhang 2026
Endogenous · Secreted at inflammation sites

01Mechanism of Action

Parameter
DSIP
LL-37
Primary target
Multiple — modulates HPA axis + thalamic delta-wave generation (proposed)Schneider 1986
Bacterial membranes · Phosphatidylserine-exposed cellsHe 2026Lu 2026
Pathway
Reduced cortisol/ACTH + enhanced delta-wave EEG activity → improved sleep onset + depthSchneider 1986
hCAP-18 precursor → Proteinase-3 cleavage → LL-37 release → Membrane insertion/disruption
Downstream effect
Faster sleep onset, increased delta sleep, reduced stress response, possible anxiolytic effectSchneider 1986
Membrane permeabilization, cytokine induction, autophagy, phagosome-lysosome fusion, chemotaxisAhmad 2026Zhang 2026
Feedback intact?
Origin
Endogenous peptide first isolated from rabbit blood during delta sleep; synthesised exogenouslySchneider 1986
Endogenous human cathelicidin (37-AA fragment, residues 134–170 of hCAP-18)
Antibody development

02Dosage Protocols

Parameter
DSIP
LL-37
Standard dose
100–200 mcg SQ pre-sleepSchneider 1986
Frequency
Once daily, pre-sleep
Lower / starter dose
50 mcg pre-sleep
Evidence basis
Human-mechanistic + early clinicalSchneider 1986
In vitro, animal models, human observational
Duration
8–12 weeks per cycle
Reconstitution
Bacteriostatic water
Timing
30–60 min pre-sleep
Half-life
Short plasma; CNS effects last hours
Endogenous expression
Constitutive in neutrophils, epithelial tissues
Upregulated during infection and inflammation.Pinheiro 2026
Exogenous (experimental)
Dose varies by study; antimalarial ~10–50 μM in vitro
No FDA-approved exogenous formulation.
Plasma levels (malaria)
Elevated in infected patients and miceHe 2026
Exogenous administration reduced parasitemia in murine models.He 2026

04Side Effects & Safety

Parameter
DSIP
LL-37
Injection site reaction
Mild irritation
Drowsiness
Expected effect (intentional)
Vivid dreams
Anecdotally reported
Long-term safety
Limited modern RCT data
Pregnancy / OB
Avoid
Cytotoxicity (high dose)
Membrane disruption in host cells at supraphysiological concentrations
Pro-inflammatory signaling
Can exacerbate inflammation in certain contexts (context-dependent)Pinheiro 2026
Biofilm formation risk
LL-37-DNA complexes may stabilize dental plaque biofilmsTanabe 2026
Theoretical cancer risk
Immunomodulatory roles in tumor microenvironment under investigation
Absolute Contraindications
DSIP
  • ·Pregnancy / breastfeeding
  • ·Concurrent CNS-depressant therapy without supervision
LL-37
Relative Contraindications
DSIP
  • ·Severe sleep apnoea (untreated)
  • ·Concurrent benzodiazepine / opioid use
LL-37
  • ·Active autoimmune disease (theoretical immune dysregulation)

05Administration Protocol

Parameter
DSIP
LL-37
1. Reconstitution
Add 1–2 mL bacteriostatic water to vial.
LL-37 is constitutively expressed in neutrophils and epithelial cells, cleaved from hCAP-18 by proteinase-3 at sites of infection or inflammation.
2. Injection site
SQ — abdomen. Rotate sites.
Synthetic LL-37 and derivatives (e.g., SAMP-12aa) tested in vitro and animal models. Administered via topical, intraperitoneal, or intravenous routes in research settings.
3. Timing
30–60 min pre-sleep.
LL-37 is resistant to pepsin degradation at gastric pH. Synthetic short peptides designed to retain this stability while reducing toxicity.Lu 2026
4. Storage
Lyophilised: room temp. Reconstituted: refrigerate ≤30 days.
5. Needle
29–31G insulin syringe.