Ingredients in the KLOW peptide stack
GHK-Cu dominates the familiar composition by mass. The other ingredients arrive with different origins and experiments, and the short TB-500 fragment needs particularly careful identification.
The familiar composition
The KLOW peptide stack commonly contains GHK-Cu 50 mg, BPC-157 10 mg, TB-500 10 mg and KPV 10 mg: 80 mg altogether. GHK-Cu accounts for 62.5% by mass. These amounts describe the contents of a preparation; a human treatment dose has not been established for the mixture.
The weighting puts copper-peptide research at the centre of this site. It supplies no clinical demonstration that this ratio is best. There is no pharmacopeial standard for KLOW, and the ingredients remain separate molecules when co-formulated.
KPV
KPV is Lys-Pro-Val, the last three amino acids of the 13-amino-acid peptide alpha-MSH. The intestinal study examined human intestinal epithelial cells and immune cells in culture, plus mouse models of colitis. KPV reduced inflammatory signalling involving NF-kappaB and MAPK, and oral KPV reduced colitis severity in those mice.
PepT1, a transporter that can carry small peptides into intestinal cells, was central to the uptake finding. The PepT1 result earns its space here by connecting an entry route to the measured inflammatory response. How that finding translates to the full mixture in a person is still open.
GHK-Cu
GHK is Gly-His-Lys; GHK-Cu is its copper complex. The skin-regeneration review recounts its isolation from human plasma in 1973 and covers collagen synthesis and matrix regulation. The aged-fibroblast work examined GHK in mouse cells, which adds an interesting qualification to the usual copper-peptide repair story.
The names GHK and GHK-Cu deserve their full wording when a claim depends on copper. The FAQ covers the blue colour and the difference between GHK-Cu alone and KLOW.
BPC-157
BPC-157 is a synthetic 15-amino-acid peptide derived from part of a protein identified in human gastric juice. Its repair reputation rests heavily on animal work, including the transected rat Achilles-tendon experiment. That study examined mechanical and functional recovery as well as tissue appearance and tendon-cell outgrowth in culture.
The gut origin is an unusual starting point for a tendon story. For me, the mechanical measurements are the compelling part of the journey. The small human studies discussed on the results page address quite different questions.
TB-500 and thymosin beta-4
TB-500 is the N-acetylated seven-amino-acid fragment Ac-LKKTETQ. Full-length thymosin beta-4 contains 43 amino acids. The fragment corresponds to an actin-binding region of the longer protein; actin helps give cells their structure and movement.
The rat wound-healing study used full-length thymosin beta-4. It reported faster re-epithelialisation, collagen deposition and angiogenesis. Those findings explain interest in this protein family while leaving the short fragment's own efficacy to be established. I give the molecule's identity priority over the familiar shorthand “TB-500 results.”
KLOW vs GLOW
GLOW contains GHK-Cu, BPC-157 and TB-500. KLOW adds KPV. The difference is an ingredient with its own anti-inflammatory research, rather than a demonstrated improvement in a controlled comparison of the blends.
Community comparisons sometimes credit KPV with a stronger sense of reduced inflammation. These are anecdotal impressions, with no head-to-head clinical result behind them. KLOW and the separately named WOLVERINE blend also have different compositions. The benefits and safety page covers the reports without turning their impressions into measured advantages.