Description
KPV is a naturally occurring tripeptide corresponding to positions 11–13 of alpha-melanocyte-stimulating hormone (alpha-MSH) — the C-terminal sequence Lys-Pro-Val. Structure-activity relationship studies systematically identified this fragment as the region of alpha-MSH that carries anti-inflammatory signaling capacity through a receptor-independent mechanism, distinct from the central core sequence (residues 6–9) responsible for melanocortin receptor binding and pigmentation effects. KPV enters cells via PepT1 di/tripeptide transporter-mediated uptake, undergoes nuclear import, and suppresses NF-κB activation by stabilizing IκBα and blocking p65 subunit nuclear translocation — a mechanism that makes it a useful research tool for studying specialty research peptide inflammatory signaling independently of receptor-mediated melanocortin pathway activity.
Key Characteristics
- Receptor-independent NF-κB suppression — KPV does not engage melanocortin receptors; instead, it enters the nucleus and inhibits p65 RelA translocation via the importin-alpha pathway, reducing transcription of downstream inflammatory mediators, including TNF-α, IL-1β, and IL-6 at nanomolar concentrations in preclinical cell models
- PepT1 transporter-mediated cellular uptake is a structurally notable property — the di/tripeptide transporter expressed on intestinal epithelial cells actively transports KPV across cell membranes, which has direct implications for how intestinal inflammation models using this compound are designed and interpreted
- Mechanistically distinct from PT-141 despite sharing alpha-MSH as the parent peptide — PT-141 acts through melanocortin MC3R and MC4R receptor binding; KPV acts intracellularly without receptor engagement, allowing researchers to separate receptor-mediated from receptor-independent anti-inflammatory signaling within the same melanocortin peptide family
- MAPK pathway inhibition and inflammasome modulation have been documented alongside NF-κB suppression — specifically reduced IL-1β and IL-18 production through inflammasome pathway interaction, adding a second mechanistic layer to KPV’s research relevance in inflammatory signaling models
- Lacks the pigmentary and appetite effects of full-length alpha-MSH — the central His-Phe-Arg-Trp core sequence responsible for MC1R binding and melanogenic cAMP signaling is absent from KPV, which was the specific research rationale for isolating this fragment as an anti-inflammatory tool
Handling and Storage
Store as lyophilized powder under refrigeration, away from heat, moisture, and light. As a tripeptide, KPV is susceptible to proteolytic degradation under suboptimal conditions. Reconstitute immediately before use and avoid repeated freeze-thaw cycles.
FAQs
What is KPV?
KPV (Lys-Pro-Val) is the C-terminal tripeptide fragment of alpha-melanocyte-stimulating hormone (alpha-MSH). It retains alpha-MSH’s anti-inflammatory signaling activity through a receptor-independent mechanism — entering cells via PepT1 transporter, stabilizing IκBα, and suppressing NF-κB nuclear translocation — while lacking the melanocortin receptor binding and pigmentation effects of the full-length parent peptide.
How does KPV’s mechanism differ from full-length alpha-MSH?
Full-length alpha-MSH exerts anti-inflammatory effects through both melanocortin receptor activation (MC1R, MC3R) and the receptor-independent mechanism carried by the KPV C-terminal sequence. KPV operates exclusively through the receptor-independent route — intracellular NF-κB suppression via IκBα stabilization. Researchers use this distinction in comparative studies designed to separate receptor-mediated from receptor-independent contributions to melanocortin peptide anti-inflammatory activity.
Why is PepT1 transporter uptake relevant to KPV research design?
PepT1 is a di/tripeptide transporter expressed at high levels on intestinal epithelial cells. Its active transport of KPV across epithelial membranes directly affects how intestinal inflammation models are designed — it provides a defined cellular uptake mechanism rather than passive diffusion, which influences dosing rationale, concentration-response relationships, and the tissue specificity of observed effects in gastrointestinal research models.
