UCHL1 aggravates skin fibrosis through an IGF-1-induced Akt/mTOR/HIF-1α pathway in keloid

FASEB J. 2023 Jul;37(7):e23015. doi: 10.1096/fj.202300153RR.

Abstract

Keloid is a heterogeneous disease featured by the excessive production of extracellular matrix. It is a great challenge for both clinicians and patients regarding the exaggerated and uncontrolled outgrowth and the therapeutic resistance of the disease. In this study, we verified that UCHL1 was drastically upregulated in keloid fibroblasts. UCHL1 had no effects on cell proliferation and migration, but instead promoted collagen I and α-SMA expression that was inhibited by silencing UCHL1 gene and by adding in LDN-57444, a pharmacological inhibitor for UCHL1 activity as well. The pathological process was mediated by IGF-1 promoted Akt/mTOR/HIF-1α signaling pathway because inhibition of any of them could reduce the expression of collagen I and α-SMA driven by UCHL1 in fibroblasts. Also, we found that UCHL1 expression in keloid fibroblasts was promoted by M2 macrophages via TGF-β1. These findings extend our understanding of the pathogenesis of keloid and provide potential therapeutic targets for the disease.

Keywords: deubiquitinating enzymes; extracellular matrix; fibroblast; keloid; skin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Proliferation
  • Cells, Cultured
  • Collagen Type I / metabolism
  • Fibroblasts / metabolism
  • Humans
  • Insulin-Like Growth Factor I / metabolism
  • Keloid* / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism
  • Skin Diseases* / metabolism
  • TOR Serine-Threonine Kinases / genetics
  • TOR Serine-Threonine Kinases / metabolism
  • Ubiquitin Thiolesterase / genetics
  • Ubiquitin Thiolesterase / metabolism

Substances

  • Collagen Type I
  • Insulin-Like Growth Factor I
  • MTOR protein, human
  • Proto-Oncogene Proteins c-akt
  • TOR Serine-Threonine Kinases
  • Ubiquitin Thiolesterase
  • UCHL1 protein, human
  • IGF1 protein, human
  • HIF1A protein, human