PE-22-28 (10 mg vial)

Protocol Overview

Concise summary of the regimen.

Dosing & Reconstitution

Frequency: Inject once daily subcutaneously. For 10 unit (0.10 mL) or smaller administrations, consider 30- or

Reconstitution Steps

1. Draw 3.0 mL bacteriostatic water with a sterile syringe.
2. Inject slowly down the vial wall; avoid foaming.
3. Gently swirl until dissolved (do not shake).
4. Label and refrigerate at 2 to 8 °C, protected from light. At 3.33 mg/mL, 1 unit = 0.01 mL » 33.3 mcg on a U-100 insulin syringe.

Storage Instructions

Proper storage preserves peptide quality.

• Lyophilized: store at -20 °C in dry, dark conditions; minimize moisture exposure.
• Reconstituted: refrigerate at 2 to 8 °C; use within 4 weeks for optimal potency.
• Allow vials to reach room temperature before opening to reduce condensation; protect from light.
• Replace with fresh vial every 4 weeks even if peptide remains; bacteriostatic water sterility is guaranteed

for 28 days after first puncture.

Supplies Needed

Plan based on an 8 to 16 week daily protocol with gradual titration. Replace vials every 4 weeks.

Peptide Vials (PE-22-28, 10 mg each):

• 8 weeks: ~2 vials. 12 weeks: ~3 vials. 16 weeks: ~4 vials.

Insulin Syringes (U-100):

• Per week: 7 syringes (1/day).
• 8 weeks: 56. 12 weeks: 84. 16 weeks: 112.

Bacteriostatic Water (10 mL bottles):

• 8 weeks (2 vials): 1 bottle. 12 weeks (3 vials): 1 bottle. 16 weeks (4 vials): 2 bottles.

Alcohol Swabs:

• Per week: 14 swabs.
• 8 weeks: 112 (2 x 100-count). 16 weeks: 224 (3 x 100-count).

Important Notes

Practical considerations for consistency and safety.

• Use new sterile insulin syringes for each injection; dispose in a sharps container immediately.
• Rotate injection sites (abdomen, thighs, upper arms) systematically to reduce local irritation.
• Inject slowly; wait a few seconds before withdrawing the needle to prevent leakage.
• Document daily dose, site rotation, and any observations to maintain protocol consistency.
• Given PE-22-28's high potency (IC50 ~0.12 nM), conservative dosing is recommended; most preclinical

effects occurred at low microgram ranges.

How This Works

PE-22-28 functions as a potent and selective antagonist of TREK-1 (KCNK2) two-pore domain potassium channels. By blocking TREK-1, it depolarizes neurons and enhances excitability, leading to increased firing of serotonergic neurons and elevated monoamine neurotransmission. This mechanism produces rapid antidepressant-like effects in preclinical models: within 4 days, PE-22-28 significantly increases hippocampal neurogenesis and synaptogenesis markers, changes typically requiring weeks with conventional antidepressants. The peptide also activates CaMKII/CREB pathways that promote neuronal survival and plasticity. PE-22-28 represents a shortened, optimized analog of spadin with superior potency (IC50 ~0.12 nM versus 40 to 60 nM for spadin) and longer duration of action (~23 hours versus ~7 hours). Research also demonstrates neuroprotective effects in stroke models through biphasic dosing.

Benefits & Side Effects

Observations from preclinical literature and mechanistic studies.

• Rapid antidepressant effects: produces behavioral improvements within 4 days in rodent models;

reduces immobility in forced swim tests and decreases latency to feed in novel environments.

• Enhanced neuroplasticity: increases hippocampal neurogenesis, synaptogenesis markers (PSD-95),

dendritic spine density, and BDNF expression within days.

• Neuroprotection: in stroke models, preserves dopaminergic neurons, reduces motor deficits, and

prevents post-stroke depressive behavior.

• Favorable safety profile: high selectivity with no effects on hERG channels (cardiac safety), no impact

on heart rate, blood pressure, glucose regulation, or pain perception in preclinical studies. No

TREK-1-related side effects or withdrawal observed.

• No human data: all evidence is from cell culture and animal studies; human safety and

pharmacokinetics remain unestablished.

• Subcutaneous administration may occasionally cause minor injection-site reactions (slight redness or

tenderness).

Lifestyle Factors

Complementary strategies for best outcomes.

• Maintain consistent sleep schedule and prioritize 7 to 9 hours of quality sleep to support neurogenesis.
• Engage in regular physical activity; both aerobic exercise and resistance training enhance BDNF and

mood-regulating pathways.

• Follow a nutrient-dense diet rich in omega-3 fatty acids, antioxidants, and B-vitamins to support brain

health.

• Practice stress-management techniques (meditation, mindfulness, therapy) to complement neuroplastic

adaptations.

• Consider cognitive training or novel learning activities to synergize with enhanced synaptic plasticity.

Injection Technique

General subcutaneous guidance from clinical best-practice resources.

1. Clean the vial stopper and skin with alcohol; allow to dry.
2. Pinch a skinfold; insert the needle at 45 to 90 degrees into subcutaneous tissue.
3. Do not aspirate for subcutaneous injections; inject slowly and steadily.
4. Wait 5 to 10 seconds before withdrawing; dispose of syringe in sharps container.
5. Rotate sites systematically (abdomen, thighs, upper arms) to avoid lipohypertrophy.

References

Source citations for further reading.

1. Mazella et al. Spadin, a sortilin-derived peptide targeting TREK-1 channels; novel antidepressant mechanism (PLoS Biology, 2010).
2. Moha Ou Maati et al. Spadin as antidepressant; absence of TREK-1-related side effects (Neuropharmacology, 2012).
3. Djillani et al. Shortened spadin analogs (PE-22-28): superior TREK-1 inhibition and antidepressant activity (Frontiers in Pharmacology, 2017).
4. Pietri et al. Protective effects on stroke recovery and post-stroke depression (Neuropharmacology, 2019).