A 3-amino-acid peptide (Lys-Pro-Val) derived from the C-terminal end of alpha-melanocyte-stimulating hormone (alpha-MSH). One of the most potent anti-inflammatory peptides known, with specific activity in the gut. Actively studied for inflammatory bowel disease.
KPV (Lys-Pro-Val) is a tripeptide corresponding to the C-terminal three amino acids (positions 11-13) of alpha-melanocyte-stimulating hormone (alpha-MSH). While alpha-MSH is primarily known for skin pigmentation, its anti-inflammatory properties have been recognized since the 1980s. KPV retains the full anti-inflammatory activity of alpha-MSH without the melanocortin receptor-dependent pigmentation effects.
KPV is particularly notable for its oral bioavailability — unusual for a peptide — and its specific activity in the gastrointestinal tract. It accumulates in inflamed colonic tissue, making it a promising candidate for treating inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis.
KPV's mechanism is distinct from other anti-inflammatory peptides because it acts intracellularly, not through cell surface receptors. After entering cells via the PepT1 peptide transporter, KPV directly inhibits the IKK-beta kinase that is required to activate NF-kB. Without IKK-beta activity, the inhibitory protein IkB-alpha remains bound to NF-kB, trapping it in the cytoplasm and preventing transcription of inflammatory genes.
| Pathway | Effect | Significance |
|---|---|---|
| NF-kB inhibition | Blocks IKK-beta phosphorylation, preventing NF-kB activation | Reduces transcription of pro-inflammatory cytokines |
| PepT1 uptake | Enters cells via peptide transporter upregulated in inflamed tissue | Preferentially accumulates in inflamed gut epithelium |
| Oral bioavailability | Survives GI transit as a small tripeptide | Can be taken orally for gut-targeted anti-inflammatory action |
| No melanocortin activity | Does not bind MC1R-MC5R receptors | No skin pigmentation or hormonal side effects |
| Antimicrobial | Direct antibacterial activity against S. aureus and Candida | May address microbial component of IBD pathogenesis |
| Study | Design | Findings | Level |
|---|---|---|---|
| Colitis models | Mouse DSS colitis | Oral and intraperitoneal KPV significantly reduced colonic inflammation, disease activity, and histological damage scores | Preclinical |
| NF-kB mechanism | In vitro, colonic epithelial cells | KPV inhibited NF-kB activation and IL-8 secretion in TNF-alpha-stimulated cells in a dose-dependent manner | Preclinical |
| Nanoparticle delivery | Mouse colitis | KPV-loaded nanoparticles targeted inflamed colon tissue with enhanced efficacy vs free KPV | Preclinical |
| Wound healing | In vitro + animal | Accelerated wound closure and reduced inflammation in skin wound models | Preclinical |
Excellent safety profile: No significant adverse effects reported in preclinical studies.
No pigmentation: Unlike full-length alpha-MSH, KPV does not activate melanocortin receptors and does not cause skin darkening.
Limited human data: No published human clinical trials. Safety in humans is inferred from the parent molecule (alpha-MSH) and the naturally occurring tripeptide.
| Jurisdiction | Status |
|---|---|
| FDA | Not approved. Not reviewed. |
| Research | Active area of IBD drug development. Multiple nanoparticle delivery systems in development. |
| Availability | Available as a research peptide and in some functional medicine protocols |