Hypoxia upregulates the synthesis of TGF-beta 1 by human dermal fibroblasts

J Invest Dermatol. 1991 Oct;97(4):634-7. doi: 10.1111/1523-1747.ep12483126.

Abstract

In this report, we have investigated the secretion and synthesis of transforming growth factor-beta 1 (TGF-beta 1) by human dermal fibroblast cultures in response to hypoxia (2% oxygen), and have compared it to standard oxygen culture conditions (15% oxygen at the cell surface). Sandwich enzyme-linked immunosorbent assay (SELISA) showed a selective and progressive increase in secretion of the TGF-beta 1 isoform in response to hypoxia, up to ninefold after cultures were exposed to low oxygen for 72 h; TGF-beta 2 peptide levels were not increased. We then investigated the transcriptional regulation of the TGF-beta 1 gene in response to low and standard oxygen tensions. In the first 24-48 h, TGF-beta 1 mRNA levels decreased steadily in both oxygen environments. This mRNA decline continued for up to 72 h in standard oxygen but not in cultures exposed to low oxygen tension. At 72 h, steady-state TGF-beta 1 mRNA levels were 8 times greater in low compared to standard oxygen, and this increase was reversible upon re-exposure of fibroblast cultures to standard oxygen tension for 24 h. Elevated TGF-beta 1 m-RNA levels in both low and standard oxygen declined steadily and with the same half-life after the addition of actinomycin D, suggesting that hypoxia increased TGF-beta 1 transcription rather than mRNA stability. We conclude that low oxygen tension upregulates the synthesis of TGF-beta 1 by human dermal fibroblasts, and leads to increased secretion of this peptide.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Cell Hypoxia*
  • Cells, Cultured
  • Fibroblasts / metabolism
  • Humans
  • RNA, Messenger / analysis
  • Skin / metabolism*
  • Transcription, Genetic
  • Transforming Growth Factor beta / biosynthesis*
  • Up-Regulation

Substances

  • RNA, Messenger
  • Transforming Growth Factor beta