PE-22-28

PE-22-28 is a synthetic heptapeptide with the sequence GVSWGLR, developed as an optimized analog of the naturally occurring peptide Spadin. It acts as a potent inhibitor of the TREK-1 (TWIK-related potassium channel 1) two-pore domain potassium channel with an IC50 of 0.12 nM, making it one of the most potent TREK-1 blockers identified.

TREK-1 channels play a critical role in neuronal excitability, mood regulation, and pain perception. These channels are widely expressed in the central nervous system, particularly in regions associated with mood and cognition including the hippocampus, prefrontal cortex, and amygdala. By blocking TREK-1, PE-22-28 increases neuronal excitability and modulates neurotransmitter release. TREK-1 knockout mice exhibit a depression-resistant phenotype, providing the biological rationale for TREK-1 inhibition as an antidepressant strategy.

Preclinical research has demonstrated that PE-22-28 produces rapid antidepressant-like effects in mouse models, comparable to established antidepressants but with a faster onset of action. Studies show it increases hippocampal neurogenesis and enhances BDNF expression. Beyond mood regulation, research has explored PE-22-28's effects on neuroprotection, stress response, and pain modulation. Compared to other nootropic peptides like Selank (anxiolytic) and Semax (cognitive enhancement), PE-22-28 is more specifically targeted toward stress regulation and mood, offering a focused mechanism for depression and stress-related conditions.