Mechanisms of Hypoxic Regulation of Plasminogen Activator Inhibitor-1 Gene Expression in Keloid Fibroblasts

Qunzhou Zhang, Yidi Wu, David K. Ann, Diana V. Messadi, Tai Lan Tuan, A. Paul Kelly, Charles N. Bertolami, Anh D. Le

Research output: Contribution to journalArticlepeer-review


Keloids are an excessive accumulation of extracellular matrix. Although numerous studies have shown elevated plasminogen activator inhibitor-1 (PAI-1) levels in keloid fibroblasts compared with those of normal skin. Their specific mechanisms involved in the differential expression of PAI-1 in these cell types. In this study, the upregulation of PAI-1 expression is demonstrated in keloid tissues and their derived dermal fibroblasts, attesting to the persistence, if any, of fundamental differences between in vivo and in vitro paradigms. We further examined the mechanisms involved in hypoxia-induced regulation of PAI-1 gene in dermal fibroblast derived from keloid lesions and associated clinically normal peripheral skins from the same patient. Primary cultures were exposed to an environmental hypoxia or desferroxamine. We found that the hypoxia-induced elevation of PAI-1 gene appears to be regulated at both transcriptional and post-transcriptional levels in keloid fibroblasts. Furthermore, our results showed a consistent elevation of HIF-1α protein level in keloid tissues compared with their normal peripheral skin controls, implying a potential role as a biomarker for local skin hypoxia. Treatment with antisense oligonucleotides against hypoxia-inducible factor 1α (HIF-1α) led to the downregulation of steady-state levels of PAI-1 mRNA under both normoxic and hypoxic conditions. Conceivably, our results suggest that HIF-1α may be a novel therapeutic target to modulate the scar fibrosis process.

Original languageEnglish (US)
Pages (from-to)1005-1012
Number of pages8
JournalJournal of Investigative Dermatology
Issue number5
StatePublished - Nov 2003


  • Antisense
  • Desferroxamine
  • HIF-1α
  • Half-life
  • Hypoxia

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Dermatology
  • Cell Biology


Dive into the research topics of 'Mechanisms of Hypoxic Regulation of Plasminogen Activator Inhibitor-1 Gene Expression in Keloid Fibroblasts'. Together they form a unique fingerprint.

Cite this