{"title":"Katayama K et al., “A pentapeptide from type I procollagen promotes extracellular matrix production”","entity_type":"Source","slug":"katayama-procollagen-pentapeptide","canonical_url":"https://skinknowledgebase.com/sources/katayama-procollagen-pentapeptide","dates":{"date_modified":"2026-05-07","date_reviewed":"2026-05-07"},"mcp_eligible":true,"evidence_sources":[],"product_fact_sources":[],"related_entities":[{"title":"Matrixyl","url":"https://skinknowledgebase.com/ingredients/matrixyl"},{"title":"What does Matrixyl do for skin?","url":"https://skinknowledgebase.com/questions/what-does-matrixyl-do-for-skin"},{"title":"Does collagen cream actually work for wrinkles?","url":"https://skinknowledgebase.com/questions/does-collagen-cream-actually-work-for-wrinkles"}],"body_sections":[{"heading":"Quick Summary","paragraphs":["The foundational mechanism paper for the Pal-KTTKS / Matrixyl pentapeptide story. Katayama and colleagues report on a pentapeptide fragment derived from type I procollagen that, in laboratory study, signals connective-tissue cells to produce more extracellular-matrix proteins. The paper underlies the cosmetic-industry framing of the Matrixyl pentapeptide as a \"signaling\" peptide."]},{"heading":"What Studied","paragraphs":["The paper reports a laboratory investigation of a small peptide fragment (KTTKS) derived from the C-terminal propeptide of type I procollagen. The researchers tested whether the pentapeptide could signal cultured fibroblasts to upregulate extracellular-matrix protein production, including collagen-family proteins and fibronectin."]},{"heading":"Main Findings","paragraphs":["The published findings indicate that the pentapeptide acts as a signal for fibroblasts to increase synthesis of collagen-family proteins and fibronectin in the studied culture system. This is the mechanism paper that the cosmetic industry later used as the rationale for marketing the palmitoyl-conjugated form (Pal-KTTKS, Matrixyl) as a topical cosmetic-appearance ingredient."]},{"heading":"Why It Matters","paragraphs":["For a Question explaining how Matrixyl works at the cosmetic-appearance layer, this source is the upstream mechanism reference. It is important to cite carefully: the paper is a laboratory study of a peptide fragment, not a clinical efficacy study of a topical cosmetic. The Question must therefore frame mechanism at the cosmetic-appearance layer and lean on the human cosmetic-appearance studies (Robinson, Schagen, Lupo & Cole) for the visible-look claim."]}],"source_type":"peer_reviewed","original_source_url":"https://pubmed.ncbi.nlm.nih.gov/8486721/"}