KPV Tripeptide (Lys-Pro-Val) - Anti-Inflammatory α-MSH Fragment

KPV for Research: Complete Scientific Overview

KPV (Lysine-Proline-Valine) is a synthetic tripeptide corresponding to the C-terminal fragment (amino acid residues 11-13) of alpha-melanocyte-stimulating hormone (α-MSH). While the full-length α-MSH peptide (13 amino acids) is known for its pigmentation effects via melanocortin receptor activation (MC1R), the KPV tripeptide has been discovered through extensive structure-activity relationship studies to retain potent anti-inflammatory and immunomodulatory activities through mechanisms independent of classical melanocortin receptors. This makes KPV a uniquely valuable research tool for studying inflammation, cytokine regulation, and immune modulation without the pigmentation-related confounding factors associated with full-length α-MSH or other melanocortin agonists. The peptide has been shown to be effective across multiple species and inflammation models, demonstrating remarkable potency despite its small size. The minimal sequence required for anti-inflammatory activity, KPV represents the culmination of decades of research into the structure-function relationships of the melanocortin peptide family. PeptideVanta offers premium-grade KPV with verified 99%+ purity through third-party HPLC testing.

Mechanism of Action

KPV exerts its anti-inflammatory effects through multiple well-characterized pathways that are distinct from classical melanocortin receptor activation:

• NF-κB Inhibition (Primary Mechanism): KPV potently suppresses nuclear factor-kappa B (NF-κB) activation, a master transcription factor regulating pro-inflammatory gene expression. By inhibiting IκB kinase (IKK) phosphorylation and subsequent IκBα degradation, KPV prevents NF-κB nuclear translocation and reduces transcription of inflammatory mediators including TNF-α, IL-1β, IL-6, COX-2, and iNOS.
• Pro-inflammatory Cytokine Suppression: KPV significantly downregulates the production and secretion of key pro-inflammatory cytokines including tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and interleukin-8 (IL-8). This cytokine modulation occurs at both the transcriptional and post-transcriptional levels.
• MAPK Pathway Modulation: KPV influences mitogen-activated protein kinase (MAPK) signaling pathways, including p38 MAPK, c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinase (ERK) 1/2, which are critical mediators of inflammatory responses and cellular stress signaling.
• Melanocortin-Independent Mechanism: Unlike full-length α-MSH, KPV does not require melanocortin receptor activation (MC1R-MC5R) for its anti-inflammatory effects, acting through distinct molecular targets. This receptor independence allows KPV to exert effects in cell types and tissues where melanocortin receptors are not expressed.
• Inflammasome Regulation: KPV modulates NLRP3 inflammasome activation and subsequent caspase-1 mediated processing of pro-IL-1β and pro-IL-18, reducing the maturation and secretion of these potent inflammatory mediators.
• Oxidative Stress Reduction: KPV decreases reactive oxygen species (ROS) production and enhances antioxidant defense mechanisms, including upregulation of superoxide dismutase (SOD), catalase, and glutathione peroxidase, reducing oxidative damage in inflammatory models.
• Chemokine Modulation: KPV reduces the expression of chemokines such as MCP-1, MIP-1α, and RANTES, thereby decreasing leukocyte recruitment and infiltration into inflamed tissues.

Key Research Applications

• Inflammatory Bowel Disease (IBD) Research: Studying the effects of KPV in colitis models, including dextran sulfate sodium (DSS)-induced and trinitrobenzene sulfonic acid (TNBS)-induced colitis, investigating mucosal inflammation, barrier function, and tissue repair.
• Dermatitis and Skin Inflammation: Investigating the anti-inflammatory effects of KPV in models of contact dermatitis, atopic dermatitis, psoriasis, and UV-induced skin inflammation.
• Rheumatoid Arthritis Research: Studying KPV in collagen-induced arthritis (CIA) and adjuvant-induced arthritis models, examining joint inflammation, cartilage destruction, and pannus formation.
• Neuroinflammation Studies: Investigating the effects of KPV on microglial activation, astrocyte reactivity, and neuronal inflammation in models of multiple sclerosis, traumatic brain injury, and neurodegenerative diseases.
• Sepsis and Systemic Inflammation: Studying the protective effects of KPV in cecal ligation and puncture (CLP) and lipopolysaccharide (LPS)-induced sepsis models, examining organ damage and survival rates.
• Wound Healing with Reduced Inflammation: Investigating the effects of KPV on wound closure rates, scar formation, and inflammatory cell infiltration in cutaneous wound healing models.
• Gastrointestinal Inflammation: Studying the effects of KPV on gastric ulcer healing, intestinal permeability, and inflammatory responses in models of gastritis and enterocolitis.
• Airway Inflammation Research: Investigating the effects of KPV in models of asthma, chronic obstructive pulmonary disease (COPD), and acute lung injury (ALI).
• Ocular Inflammation: Studying the effects of KPV in models of uveitis, dry eye disease, and corneal inflammation.
• Inflammatory Pain Research: Investigating the analgesic and anti-inflammatory effects of KPV in models of inflammatory pain, including carrageenan-induced hyperalgesia and formalin tests.

Comparative Analysis: KPV vs. Full-Length α-MSH

• KPV (3 amino acids): Minimal anti-inflammatory tripeptide; retains potent anti-inflammatory activity (ED50 comparable to α-MSH in some models); no melanocortin receptor activation; no pigmentation effects; melanocortin-independent mechanism; highly soluble; excellent stability.
• α-MSH (13 amino acids): Full-length hormone; activates melanocortin receptors (MC1R-MC5R); induces pigmentation; broader spectrum of biological activities; larger molecular size; more complex pharmacology.
• Other α-MSH fragments: Various intermediate fragments (e.g., α-MSH 1-13, 1-10, 4-10, 6-9, 11-13) show different activity profiles, with KPV (11-13) representing the minimal active anti-inflammatory sequence.

Discovery and Research Significance

The identification of KPV as the minimal active anti-inflammatory sequence of α-MSH represents a landmark discovery in peptide pharmacology. Through systematic deletion studies, researchers determined that while the central tetrapeptide His-Phe-Arg-Trp (α-MSH 6-9) is critical for melanocortin receptor binding and pigmentation, the C-terminal tripeptide KPV (α-MSH 11-13) retains significant anti-inflammatory activity through entirely different mechanisms. This finding has important implications for drug development, as KPV offers a simplified, more stable, and more selective anti-inflammatory peptide without the pigmentation and other off-target effects of full-length α-MSH. The discovery has led to numerous patents and clinical investigations into KPV-based therapeutics for inflammatory diseases.

Chemical Information

CAS Number: 160522-97-8
Research Codes: KPV, Lys-Pro-Val, α-MSH (11-13), Anti-inflammatory tripeptide, KPV tripeptide
Molecular Formula: C16H29N5O4
Molecular Weight: 355.4 g/mol
Sequence: H-Lys-Pro-Val-OH (Lysine-Proline-Valine)
Number of Amino Acids: 3 (tripeptide)
Isoelectric Point (pI): 10.5 (basic peptide)
Net Charge at pH 7.4: +1 (positively charged)
Purity: >99% (HPLC)
Form: Lyophilized powder
Solubility: Soluble in water, saline, PBS, and DMSO (excellent aqueous solubility due to basic lysine residue)
Storage: -20°C (lyophilized), 4°C (reconstituted)
Stability: Stable at -20°C for 24 months; reconstituted solution stable at 4°C for 30 days

Reconstitution and Handling Protocols

For optimal stability and research validity, KPV should be reconstituted with sterile bacteriostatic water, sterile saline (0.9% NaCl), or sterile PBS. Due to its basic nature (pI 10.5) and excellent aqueous solubility, KPV dissolves readily in water-based solutions without the need for organic solvents or pH adjustment. Allow the lyophilized powder to dissolve completely without vigorous shaking to maintain peptide integrity. Gently swirl the vial until the solution is clear and free of particulates. Once reconstituted, the solution should be stored at 4°C and used within 30 days. Avoid repeated freeze-thaw cycles to preserve peptide structure and biological activity. For long-term storage, keep the lyophilized powder at -20°C away from light and moisture. Do not vortex or vigorously shake the reconstituted solution, as this may cause aggregation and reduce biological activity.

Quality Assurance

PeptideVanta's KPV undergoes rigorous quality control including HPLC purity analysis (>99%), ESI-mass spectrometry for molecular weight confirmation (expected 355.4 Da), amino acid analysis to confirm correct composition, endotoxin testing (<1.0 EU/mg), sterility testing, and residual solvent analysis. Each batch is accompanied by a Certificate of Analysis (COA) with complete testing results. The peptide is synthesized using solid-phase peptide synthesis (SPPS) with Fmoc chemistry, followed by HPLC purification and lyophilization under sterile conditions.