PE-22-28 (10 mg vial)

Protocol Overview

Concise summary of the regimen.

Dosing & Reconstitution

Frequency is one subcutaneous injection daily for the length of the course. At 10 mg/mL every dose in this protocol falls between 0.5 and 2 units, which is a very small mark on a standard U-100 barrel, so a 30 unit or 50 unit insulin syringe is the sensible choice for readability and a 30 unit barrel with half unit graduations makes the 50 mcg and 150 mcg steps measurable rather than estimated. Sites are rotated systematically across abdomen, thighs, and upper arms to reduce local irritation, with the needle entering at 45 to 90 degrees into subcutaneous tissue, no aspiration, a slow steady push, and 5 to 10 seconds before withdrawal. Many researchers find 100 to 150 mcg sufficient given PE-22-28's high potency, so the optional weeks 9 to 16 escalations are not a default destination.

Results Timeline

Sequence described in the research record. Individual response varies.

• Weeks 1 to 2: the protocol opens at 50 mcg daily, the conservative entry point given the peptide's reported IC50 of about 0.12 nM.
• Within about 4 days of exposure: preclinical models show significant increases in hippocampal neurogenesis and synaptogenesis markers, changes that conventional antidepressants take weeks to produce. Behavioral improvements in rodents appear on the same rapid timescale.
• Weeks 3 to 8: the dose sits at 100 mcg daily, which is the maintenance band where a substantial share of researchers stop. Eight weeks is the minimum course length in the master schedule.
• Weeks 9 to 12 (optional): 150 mcg daily, taken only if the lower band has not been adequate.
• Weeks 13 to 16 (optional): 200 mcg daily, the top of the range and the end of a full 16 week course. Vials are replaced every 4 weeks throughout, independent of dose.

Reconstitution Steps

1. Draw 1.0 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 with date and concentration; refrigerate at 2 to 8 °C, protected from light. At 10 mg/mL, 1 unit = 0.01 mL » 100 mcg on a U-100 insulin syringe, so 50 mcg is 0.5 units, 100 mcg is 1 unit, 150 mcg is 1.5 units, and 200 mcg is 2 units.

Storage Instructions

Proper storage preserves peptide quality.

• Lyophilized: store at minus 20 °C in dry, dark conditions and minimize moisture exposure.
• Reconstituted: refrigerate at 2 to 8 °C and use within 4 weeks for optimal potency.

• Allow vials to reach room temperature before opening to reduce condensation, and protect from light throughout.
• Replace with a fresh vial every 4 weeks even when peptide remains, because bacteriostatic water sterility is only guaranteed for 28 days after first puncture.

Supplies Needed

Planning math is based on a 12 to 16 week daily protocol with gradual titration, which is 700 mcg (0.7 mg) per week at the 100 mcg maintenance dose and 1.4 mg per week at the 200 mcg top of the range, with vials replaced every 4 weeks regardless of how much peptide is left.

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

• A full 16 week titration consumes about 14.7 mg of peptide, a 12 week course about 9.1 mg, and an 8 week minimum course about 4.9 mg, but the 4 week replacement rule sets the count rather than the math: 2 vials of 10 mg for 8 weeks, 3 vials for 12 weeks, and 4 vials for 16 weeks. At 1.0 mL per vial each vial holds roughly 100 maintenance doses, so most of it is discarded at the 28 day mark.

Insulin Syringes (U-100):

• Per week: 7 U-100 insulin syringes, one per day. At 0.5 to 2 units per dose a 30 unit barrel with half unit graduations is the practical choice.
• Full cycle: 56 syringes for 8 weeks, 84 for 12 weeks, and 112 for 16 weeks.

Bacteriostatic Water (10 mL bottles):

• Each 10 mg vial takes 1.0 mL of bacteriostatic water, so one 10 mL bottle reconstitutes 10 vials, comfortably more than the 4 vials a full 16 week course requires.

Alcohol Swabs:

• Per injection: 2 alcohol swabs, one for the vial stopper and one for the skin, which is 14 per week on the once daily schedule.
• Full cycle: 112 swabs for 8 weeks, 168 for 12 weeks, and 224 for 16 weeks, which is two to three boxes of 100.

Important Notes

Practical considerations for consistency and safety.

• Measurement precision is the main practical constraint at this concentration. A 50 mcg dose is half of one unit on a U-100 syringe, so a 30 unit barrel with half unit graduations is what makes the early titration steps readable rather than guessed.
• Given PE-22-28's high potency (IC50 about 0.12 nM), conservative dosing is the default. Most preclinical effects occurred at low microgram ranges, so escalating past 150 mcg is an option rather than an expectation.
• A vial is retired at 4 weeks even with most of its volume remaining, because bacteriostatic water sterility is only guaranteed for 28 days after first puncture. The discarded peptide is the cost of that rule, not a sign of miscalculation.
• Use a new sterile insulin syringe for every injection and dispose of it in a sharps container immediately. Rotate sites systematically across abdomen, thighs, and upper arms, and inject slowly, waiting a few seconds before withdrawing the needle to prevent leakage.
• Document the daily dose, the site used, and any observations. On a protocol running 12 to 16 weeks with optional escalation points, written records are what make the titration decisions at weeks 9 and 13 something other than a guess.
• Regulatory Note: PE-22-28 is not approved by any regulatory agency for human use. All available evidence comes from cell culture and animal studies, so human safety and pharmacokinetics remain unestablished, and the compound is supplied for research purposes only and not for human consumption. The master sheet does not record a WADA classification for this compound.

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, which increases firing of serotonergic neurons and raises monoamine neurotransmission. In preclinical models this produces rapid antidepressant-like effects: within 4 days PE-22-28 significantly increases hippocampal neurogenesis and synaptogenesis markers, changes that typically require weeks with conventional antidepressants. The peptide also activates CaMKII/CREB pathways that promote neuronal survival and plasticity. PE-22-28 is a shortened, optimized analog of spadin with superior potency (IC50 about 0.12 nM against 40 to 60 nM for spadin) and longer duration of action (about 23 hours against about 7 hours). Research also demonstrates neuroprotective effects in stroke models through biphasic dosing.

Benefits & Side Effects

Observations from the published record.

• Rapid antidepressant effects: behavioral improvements within 4 days in rodent models, including reduced immobility in forced swim tests and decreased latency to feed in novel environments.
• Enhanced neuroplasticity: increases in hippocampal neurogenesis, synaptogenesis markers (PSD-95), dendritic spine density, and BDNF expression within days.
• Neuroprotection: in stroke models, preservation of dopaminergic neurons, reduced motor deficits, and prevention of post-stroke depressive behavior.
• Favorable safety profile: high selectivity with no effects on hERG channels, meaning cardiac safety in the preclinical data, and no impact on heart rate, blood pressure, glucose regulation, or pain perception. No TREK-1-related side effects or withdrawal were observed.
• No human data: all evidence is from cell culture and animal studies, so human safety and pharmacokinetics remain unestablished.
• Subcutaneous administration may occasionally cause minor injection-site reactions such as slight redness or tenderness.

Lifestyle Factors

Complementary strategies for best outcomes.

• Maintain a consistent sleep schedule and prioritize 7 to 9 hours of quality sleep, which is when neurogenesis is best supported.
• Engage in regular physical activity. Both aerobic exercise and resistance training enhance BDNF and mood-regulating pathways independently of the peptide.
• Follow a nutrient-dense diet rich in omega-3 fatty acids, antioxidants, and B-vitamins to support brain health.
• Practice stress-management techniques such as meditation, mindfulness, or therapy, and consider cognitive training or novel learning activities that 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).