PE-22-28 (8mg) – Spadin Analogue Research Peptide

PE-22-28 (8mg) is a synthetic heptapeptide derived from the spadin peptide family and investigated primarily in preclinical neuroscience research. PE-22-28 was developed as a shortened analogue of spadin and has been studied for its interaction with the TREK-1 (TWIK-related potassium channel 1), a two-pore-domain potassium channel involved in regulating neuronal excitability.

Published research has investigated PE-22-28 in cellular and animal models, including studies examining TREK-1 channel activity, antidepressant-like behavioural responses, hippocampal neurogenesis and synaptic plasticity.

In electrophysiological experiments, PE-22-28 demonstrated stronger TREK-1 inhibitory activity than the parent spadin peptide. These findings remain preclinical and should not be interpreted as evidence of established safety or efficacy in humans.

The 8mg format provides a defined research quantity for qualified laboratories investigating peptide pharmacology, ion-channel biology, neuronal signalling and related experimental models. The product should be handled exclusively according to appropriate laboratory procedures and applicable regulations.

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What Is PE-22-28?

PE-22-28 is a synthetic peptide analogue derived from spadin. Spadin is an endogenous peptide associated with the sortilin (NTSR3) propeptide and was previously investigated as an inhibitor of the TREK-1 potassium channel.

Researchers subsequently examined shorter fragments of spadin to identify sequences that retained TREK-1 activity while potentially offering improved stability. PE-22-28 was identified as a seven-amino-acid fragment with potent TREK-1 inhibitory activity in experimental systems.

Unlike many commercially discussed peptides that are investigated primarily for metabolic or tissue-repair pathways, PE-22-28 belongs to an area of neuropharmacological research centred on ion channels, neuronal excitability and experimental models of mood-related behaviour.

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PE-22-28 (8mg) Specifications

Specification	Details
Product Name	PE-22-28
Alternative Description	Spadin analogue
Peptide Type	Synthetic heptapeptide
Quantity	8mg
Research Target	TREK-1 potassium channel
Primary Research Field	Neuropharmacology and neuronal signalling
Additional Research Areas	Neurogenesis, synaptic biology and behavioural neuroscience
Research Stage	Preclinical
Intended Use	Laboratory and in-vitro research only

The referenced Core Peptides listing identifies the product as an 8mg lyophilised research peptide and describes it as being supplied for laboratory and in-vitro research rather than human use.

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PE-22-28 Peptide Sequence

Published literature describes PE-22-28 as a seven-amino-acid peptide derived from the corresponding region of spadin. The sequence is commonly reported as:

Gly-Val-Ser-Trp-Gly-Leu-Arg (GVSWGLR)

This shortened sequence was selected during research into spadin degradation products and analogues. The 2017 study by Djillani and colleagues describes PE-22-28 as a seven-amino-acid peptide designed to retain the relevant TREK-1 activity of spadin while improving experimental stability and duration.

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PE-22-28 and Spadin

PE-22-28 is closely related to spadin, but the two compounds are not identical.

Spadin is a longer endogenous peptide derived from the sortilin propeptide. PE-22-28 is a substantially shorter synthetic fragment designed through sequence analysis of spadin degradation products.

Characteristic	Spadin	PE-22-28
Relationship	Parent peptide	Shortened analogue
Research Target	TREK-1	TREK-1
Research Field	Neuropharmacology	Neuropharmacology
Research Models	Cellular and animal models	Cellular and animal models
Experimental Focus	Ion-channel inhibition and behavioural models	Ion-channel inhibition, stability and behavioural models

Published work found that PE-22-28 retained potent TREK-1 inhibition and displayed improved experimental duration compared with spadin in the models examined.

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PE-22-28 and TREK-1 Research

The principal scientific interest in PE-22-28 concerns its interaction with TREK-1, also known as KCNK2. TREK-1 belongs to the two-pore-domain potassium channel family and contributes to the regulation of membrane potential and neuronal excitability.

Researchers investigating TREK-1 are interested in how modulation of this channel affects neuronal signalling. PE-22-28 provides an experimental tool for studying TREK-1 inhibition in controlled cellular systems.

In patch-clamp experiments using human TREK-1-expressing HEK cells, the 2017 study reported an IC₅₀ of approximately 0.12 nM for PE-22-28 under the experimental conditions used. The same study reported an IC₅₀ of approximately 40–60 nM for spadin in comparable experiments.

These values are experimental assay results, not clinical dosing recommendations or evidence of therapeutic potency in humans.

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Why TREK-1 Is Important in Research

TREK-1 is a potassium channel that participates in the regulation of neuronal membrane properties. Because potassium-channel activity can influence neuronal excitability, TREK-1 has attracted attention in neurobiology and neuropharmacology.

Animal research has suggested a relationship between TREK-1 activity and behavioural responses relevant to mood research. PE-22-28 allows investigators to explore this relationship pharmacologically without relying solely on genetic manipulation of the channel.

This makes the peptide particularly relevant to researchers studying the connection between ion-channel activity, neuronal excitability and behavioural neuroscience.

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PE-22-28 and Antidepressant-Like Research

PE-22-28 has been investigated in animal behavioural models designed to evaluate antidepressant-like responses.

In the 2017 study, PE-22-28 and related analogues were evaluated in behavioural models including the forced swimming test and novelty-suppressed feeding test. The researchers reported changes in behavioural endpoints following experimental administration in mice.

These results are scientifically relevant because they provide a basis for studying TREK-1 as a potential neuropharmacological target. However, behavioural effects observed in rodents cannot be assumed to demonstrate antidepressant efficacy or safety in humans.

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PE-22-28 and Neurogenesis Research

Neurogenesis refers to the formation of new neurons. Experimental research has investigated whether PE-22-28 influences neurogenesis in the brain, particularly within the hippocampus.

The published study reported that PE-22-28 and related spadin analogues were able to induce measurable neurogenesis after a four-day experimental treatment period in the animal models used. A modified analogue produced a particularly prominent effect in that experimental setting.

These observations have made PE-22-28 relevant to research examining the relationship between TREK-1 signalling and neuronal plasticity.

Importantly, the available evidence is preclinical. There is no basis for presenting PE-22-28 as a proven neurogenic treatment for humans.

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PE-22-28 and Synaptogenesis

Synaptogenesis is the formation and organisation of synaptic connections between neurons. It is an important area of neuroscience research because synaptic structure and function contribute to learning, memory and neuronal communication.

Research involving mouse cortical neurons examined the effect of PE-22-28 analogues on synaptic markers. The study reported increased expression of PSD-95, a protein commonly used as a marker of excitatory postsynaptic structures, following experimental treatment.

Such results provide a foundation for further investigation into the relationship between TREK-1 channel modulation and neuronal plasticity.

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PE-22-28 and Experimental Stability

One of the objectives behind developing PE-22-28 was to investigate whether shorter spadin-derived sequences could provide improved stability compared with the parent peptide.

The published study reported that the biological activity of spadin diminished after approximately seven hours in the experimental model, whereas PE-22-28 and its analogues displayed substantially longer activity under the conditions investigated. Some analogues demonstrated activity lasting up to approximately 23 hours.

These observations concern experimental animal and cellular models and should not be interpreted as human pharmacokinetic data.

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PE-22-28 Research Applications

Qualified researchers may investigate PE-22-28 in several areas of preclinical science, including:

• TREK-1 channel research: Investigation of two-pore-domain potassium-channel inhibition.
• Ion-channel pharmacology: Evaluation of peptide-mediated modulation of neuronal ion channels.
• Neuronal excitability: Study of how TREK-1 activity affects neuronal membrane properties.
• Neuropharmacology: Investigation of novel peptide-based mechanisms affecting neuronal signalling.
• Behavioural neuroscience: Experimental research using validated animal behavioural models.
• Neurogenesis research: Investigation of changes in hippocampal neuronal formation in preclinical systems.
• Synaptic biology: Examination of synaptic proteins and markers such as PSD-95.
• Peptide analogue research: Comparison of PE-22-28 with spadin and related derivatives.
• Peptide stability: Investigation of sequence modifications and biological duration.
• Structure–activity research: Examination of how specific peptide residues influence TREK-1 activity.

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PE-22-28 in Cellular Research

Cellular models allow researchers to investigate PE-22-28 under controlled conditions and directly assess interactions with specific molecular targets.

The published literature includes experiments using HEK cells expressing human TREK-1. Patch-clamp electrophysiology was used to examine channel activity and determine the inhibitory potency of PE-22-28.

Other experiments have used cultured mouse cortical neurons to investigate downstream markers associated with synaptic structure.

These systems provide complementary information: ion-channel experiments can help characterise direct pharmacological activity, while neuronal culture models can be used to investigate downstream cellular responses.

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PE-22-28 in Animal Research

Preclinical animal studies have investigated PE-22-28 and related spadin analogues using behavioural and neurobiological endpoints.

Research has included mouse models examining antidepressant-like behaviour and tests of hippocampal neurogenesis. The 2017 study reported significant behavioural changes in the forced swimming and novelty-suppressed feeding paradigms following experimental treatment.

Although such models are useful for investigating biological mechanisms, they do not establish clinical effectiveness. Results from animal behavioural studies require further validation through appropriately designed translational and human research.

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PE-22-28 and the Blood–Brain Barrier

Because PE-22-28 is investigated in the context of central nervous system biology, researchers may consider questions surrounding peptide distribution and access to neural tissue.

However, human pharmacokinetic and blood–brain barrier data for PE-22-28 are not established. Available evidence is primarily preclinical, and experimental findings from animal models should not be used to infer human distribution or exposure.

This distinction is important when designing experiments or interpreting results involving central nervous system peptides.

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PE-22-28 and Human Research

The available published evidence for PE-22-28 is predominantly derived from cellular and animal research. Current research summaries identify an absence of established human clinical evidence for the compound.

Consequently, there are no established human therapeutic doses, clinical efficacy parameters or comprehensive human safety profiles for PE-22-28.

Researchers should therefore treat PE-22-28 as an early-stage research compound rather than a clinically validated medicine.

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PE-22-28 vs Spadin

Feature	PE-22-28	Spadin
Relationship	Shortened analogue	Parent peptide
Research Target	TREK-1	TREK-1
Research Stage	Preclinical	Preclinical
Primary Research	Ion-channel pharmacology and neuroscience	Ion-channel pharmacology and neuroscience
Experimental Stability	Improved in published analogue studies	Shorter activity reported in comparison studies
Human Clinical Evidence	Not established	Not established

The published 2017 research specifically investigated shortened spadin analogues to identify compounds with improved TREK-1 activity and in-vivo stability. PE-22-28 demonstrated stronger TREK-1 inhibition than spadin in the reported electrophysiological assays.

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PE-22-28 and Structure–Activity Research

PE-22-28 is particularly useful as a subject of structure–activity relationship (SAR) research. SAR studies investigate how changes to a molecule’s structure influence its biological activity.

The development of PE-22-28 involved examining degradation products of spadin and identifying shorter sequences capable of maintaining TREK-1 activity. Researchers also tested modifications to the N- and C-terminal regions of PE-22-28 to determine how structural changes affected activity.

This makes the peptide relevant to researchers investigating how individual amino-acid residues contribute to ion-channel binding and inhibition.

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PE-22-28 and TREK-1 Electrophysiology

Patch-clamp electrophysiology is a widely used laboratory technique for measuring ion-channel activity in individual cells.

In published PE-22-28 research, patch-clamp experiments using human TREK-1-expressing HEK cells were used to characterise the inhibitory effect of the peptide. The reported IC₅₀ value of approximately 0.12 nM provides a quantitative measure of activity within that specific experimental system.

Researchers can use similar electrophysiological approaches to compare PE-22-28 with other TREK-1 modulators or modified peptide analogues.

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PE-22-28 and PSD-95 Research

PSD-95 is a postsynaptic scaffolding protein frequently used as a marker in studies of excitatory synapses.

The published research examined PE-22-28 derivatives in mouse cortical neurons and reported increased PSD-95 expression following experimental exposure. This finding was interpreted as evidence supporting an effect on synaptogenesis in the experimental system.

Further research would be needed to establish the molecular pathway responsible for this observation and determine whether comparable effects occur across other neuronal systems.

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Quality and Analytical Considerations for PE-22-28

When working with research peptides, accurate identification and analytical characterisation are important for reproducible experiments.

Researchers sourcing PE-22-28 should consider documentation covering:

• Peptide identity confirmed through an appropriate analytical method.
• Purity assessment using an appropriate chromatographic technique.
• Mass confirmation where applicable.
• Lot or batch identification for experimental traceability.
• Certificate of analysis where supplied.
• Storage information provided by the manufacturer.
• Material form, such as lyophilised research material.

The referenced Core Peptides listing describes its PE-22-28 product as lyophilised, with purity reported at greater than 99% by reverse-phase HPLC and identity confirmed by ESI mass spectrometry. Researchers should verify the current batch-specific certificate of analysis before use.

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Handling and Storage Considerations

PE-22-28 is supplied as a research peptide and should be handled according to the manufacturer’s current technical documentation and the requirements of the laboratory conducting the work.

The referenced listing describes the material as a lyophilised powder in a sealed vial and provides specific storage recommendations for the dry and reconstituted material.

Storage conditions should always be verified against the current batch documentation, as peptide stability can depend on formulation, concentration, moisture exposure, temperature, light and repeated handling.

Reconstitution, aliquoting and experimental preparation should be performed only by appropriately trained laboratory personnel using validated institutional procedures.

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Frequently Asked Questions About PE-22-28 (8mg)

What is PE-22-28?

PE-22-28 is a synthetic seven-amino-acid peptide derived from spadin and investigated primarily as a TREK-1 potassium-channel inhibitor in preclinical neuroscience research.

What is PE-22-28 derived from?

PE-22-28 is a shortened analogue of spadin, an endogenous peptide associated with the sortilin propeptide. Researchers developed PE-22-28 by examining spadin degradation products and identifying a shorter sequence that retained TREK-1 activity.

What is the sequence of PE-22-28?

Published research describes PE-22-28 as the heptapeptide Gly-Val-Ser-Trp-Gly-Leu-Arg (GVSWGLR).

What is the main research target of PE-22-28?

The principal research target is TREK-1, a two-pore-domain potassium channel involved in regulating neuronal excitability.

Has PE-22-28 been studied for depression?

PE-22-28 has been investigated in animal behavioural models commonly used in preclinical research on antidepressant-like activity. However, these results do not establish that PE-22-28 treats depression in humans.

Has PE-22-28 been tested in humans?

Established human clinical evidence is not currently available. Research is predominantly preclinical, involving cellular and animal models.

Has PE-22-28 been studied for neurogenesis?

Yes. Published animal research reported increased neurogenesis following experimental treatment with PE-22-28 and related analogues. These findings remain preclinical.

Has PE-22-28 been studied for synaptic plasticity?

Research using mouse cortical neurons has investigated synaptic markers including PSD-95 and reported increased expression following exposure to PE-22-28 derivatives.

What does the 8mg designation mean?

The 8mg designation refers to the quantity of PE-22-28 research material supplied in the referenced product configuration. It does not represent a recommended human dose.

Is PE-22-28 a medicine?

No. PE-22-28 is an experimental research compound and should not be marketed or described as an approved medicine. Its available evidence is primarily preclinical.

Can PE-22-28 be used for self-administration?

No. The referenced product is designated for laboratory and in-vitro research only. It is not intended for human or veterinary administration.

Why is TREK-1 important in PE-22-28 research?

TREK-1 is a two-pore-domain potassium channel involved in neuronal membrane regulation. Its interaction with PE-22-28 makes the peptide a useful experimental compound for investigating ion-channel pharmacology and neuronal signalling.

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PE-22-28 (8mg) Research Summary

PE-22-28 (8mg) is a synthetic spadin analogue investigated primarily in preclinical neuropharmacology research. The peptide is a seven-amino-acid fragment derived from spadin and has been studied for its ability to inhibit the TREK-1 potassium channel.

Published studies have investigated PE-22-28 using electrophysiological cell models and animal systems. Research has explored TREK-1 inhibition, behavioural responses, hippocampal neurogenesis, synaptic markers and peptide stability. In one electrophysiological study, PE-22-28 demonstrated substantially greater TREK-1 inhibitory potency than the parent spadin peptide under the reported experimental conditions.

Despite these findings, PE-22-28 remains an early-stage research compound. Preclinical observations cannot be used to establish human efficacy, safety, pharmacokinetics or an appropriate clinical dose. Current research therefore supports its use as an experimental tool rather than as a therapeutic product.

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Research-Use Disclaimer

PE-22-28 (8mg) is intended exclusively for qualified laboratory, analytical and in-vitro research purposes. It is not a food, dietary supplement, cosmetic, medicinal product or medical device and is not intended for human or veterinary consumption or administration.

Any references to antidepressant-like activity, neurogenesis, synaptogenesis, TREK-1 inhibition or other biological effects describe findings from experimental research models. They should not be interpreted as established medical benefits, therapeutic claims or recommendations for the treatment of depression or any other condition.

Researchers should review the current certificate of analysis, safety documentation and manufacturer specifications for the applicable batch before beginning experimental work. All handling, storage, preparation and disposal should be performed by appropriately qualified personnel in accordance with institutional procedures and applicable legislation.

For research use only. Not for human or veterinary use.