Side-by-side · Research reference
PE 22-28vsPTD-DBM
Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.
AAnimal-StrongHUMAN-REVIEWED16/47 cited
BAnimal-StrongHUMAN-REVIEWED10/40 cited
PE 22-28
TREK-1 Antagonist · Pre-Clinical
IP · SQ · Once Daily (animal models)Djillani 2017Pietri 2019
01Mechanism of Action
Parameter
PE 22-28
PTD-DBM
Primary target
TREK-1 two-pore-domain potassium channelDjillani 2017Ma 2020
CXXC5–Dishevelled protein-protein interaction
Pathway
TREK-1 channel blockade → Neuronal membrane depolarisation → Enhanced hippocampal excitability → Increased neuroplasticity
Downstream effect
Antidepressant-like activity in forced swim test and tail suspension test; reduced A1-like reactive astrocyte activation; neuroprotection via NF-κB pathway modulationDjillani 2017Cong 2023Wu 2021
Activated Wnt/β-catenin signaling promotes hair follicle regeneration, dermal stem cell activation, reduced myofibroblast differentiation
Feedback intact?
N/A — direct ion channel blockade; not receptor-mediated endocrine axis
Not applicable — pathway derepression rather than receptor agonism
Origin
Synthetic truncation of spadin (PE 12-28), itself derived from the sortilin propeptide C-terminus. Residues 22-28: Val-Val-Arg-Gly-Trp-Leu-Arg.Djillani 2017Mazella 2018
Engineered fusion: cell-penetrating PTD sequence + Dvl-binding motif targeting CXXC5
Antibody development
Not reported in animal studies
—
02Dosage Protocols
Parameter
PE 22-28
PTD-DBM
Animal dose (antidepressant)
0.3–3 µg/kg IP
Effective in forced swim test, tail suspension test, CUMS models.
—
Animal dose (neuroprotection)
0.03 µg/kg IPPietri 2019
Low-dose TREK-1 activation post-stroke for 7 days, then high-dose blockade.
—
Frequency
Once daily
Sustained antidepressant effect over 7+ days.
—
Onset (animal)
Within hours (acute); full effect 4–7 days
—
Comparison to fluoxetine
PE 22-28 outperforms fluoxetine in CUMS-sensitive rats by day 7
Chronic administration shows superior long-term efficacy.
—
Human equivalent (extrapolated)
Not established — no clinical trials
Allometric scaling from rodent data unavailable.
—
Evidence basis
Multiple rodent RCTs; behavioral + electrophysiology endpointsDjillani 2017Qi 2018Wu 2021
Animal models only (mice)
Wound healing protocol
—
Hydrogel patch delivery (concentration not disclosed)
Pyrogallol-HA patch, murine model.
Hair regeneration protocol
—
Topical application (exact dose not disclosed)
Wound-induced hair neogenesis model, mice.
Co-administration
—
Valproic acid (GSK-3β inhibitor) for wound healing synergyLee 2023
Combined treatment maximized scar reduction.
Human translation
—
No published human studies
04Side Effects & Safety
Parameter
PE 22-28
PTD-DBM
Toxicity (animal)
No adverse effects reported at therapeutic doses
—
Cardiovascular (theoretical)
TREK-1 expressed in cardiac tissue; arrhythmia risk unclear
—
Weight change
Not reported in animal studies
—
Neurological
No seizures or behavioral abnormalities noted
—
Long-term safety
Unknown — longest animal study 28 days
Unknown — no chronic dosing or human data
Reported adverse events
—
None reported in animal studies
Wnt pathway activation risks
—
Theoretical risk of aberrant proliferation; Wnt dysregulation linked to tumorigenesis
Delivery vehicle effects
—
HA-PG hydrogel well-tolerated in mice; human translation pending
Absolute Contraindications
PE 22-28
- ·Human use — no clinical safety data available
PTD-DBM
- ·Active malignancy (Wnt pathway involvement in tumorigenesis)
- ·Pregnancy / lactation (no safety data)
Relative Contraindications
PE 22-28
- ·Cardiac arrhythmia or channelopathy (theoretical TREK-1 cardiac role)
PTD-DBM
- ·History of Wnt-driven tumors
- ·Skin lesions with uncertain malignant potential
05Administration Protocol
Parameter
PE 22-28
PTD-DBM
1. Animal protocol (IP)
Dissolved in sterile saline or vehicle. Intraperitoneal injection, 0.3–3 µg/kg body weight. Once daily administration in rodent behavioral studies.
Pyrogallol-functionalized hyaluronic acid (HA-PG) hydrogel patch loaded with PTD-DBM peptide, applied directly to wound bed. Adhesive hydrogel provides sustained release over multiple days.Lee 2023
2. Stability
Shorter peptide length (7 AA) confers improved plasma stability vs 17-AA spadin. Exact storage conditions not detailed in published protocols.Djillani 2017
Topical application to scalp or wound site. Precise formulation not disclosed; studies used Cxxc5 knockout or direct peptide application in wound-induced hair neogenesis models.Ryu 2023
3. BBB penetration
Enhanced CNS bioavailability vs full spadin, likely due to smaller size. Mechanism (passive diffusion vs active transport) not fully characterized.
PTD-DBM + valproic acid (GSK-3β inhibitor) in HA-PG patch showed synergistic effect on scar reduction and regenerative wound healing. VPA enhances Wnt pathway activation downstream.Lee 2023
4. Human formulation
Not established — peptide synthesis methods for research use only. No pharmaceutical-grade formulation available.
Not disclosed in available literature. Peptide stability and storage conditions not published.