J Korean Rheum Assoc.  2002 Mar;9(1):23-33.

Hypoxia Increases the Expression of ICAM-1 in Cultured Human Synovial Fibroblasts

• Jeon HS
• Baek HS
• Hwang BY
• Yoo WH

Abstract

OBJECTIVE
Hypoxic conditions are thought to be exist in inflamed arthritic synovium.Several in vitro and in vivo studies indicate that hypoxia can initiate events that lead to pro-adhesive changes.Therefore,this study was designed to examine the effects of hypoxia on the expression of ICAM-1 by cultured human synovial fibroblasts.
METHODS
Synovial fibroblasts were isolated from patients with RA and cultured at hypoxic condition.To quantify the expression of ICAM-1 mRNA in synovial fibroblasts,RT-PCR was performed.The levels of cytokines in culture supernatants were measured by ELISA.The activation of NF- RESULTS
The expression ICAM-1 mRNA was increased at 12 to 48 hours of hypoxic stimuli and peaked at 24 hours (p < 0.01).The concentration of IL-1 and TNF-alpha was increased as the duration of hypoxic stimuli was increased.Hypoxia also induced activatation of NF- microB,which was inhibited by antioxidant (pyrroli-dine dithiocarbamate). Fibroblast-lymphocyte adhesive interaction was increased significantly by hypoxic stimuli (p < 0.01).
CONCLUSIONS
Synovial hypoxia may have an important role in inflammatory synovitis,in part,as a cause of adhesion molecule (ICAM-1)expression in synovial fibroblasts and recruitment of inflammatory cells.

Keyword

Hypoxia; ICAM-1; Synovial fibroblasts

MeSH Terms

Adhesives
Anoxia*
Cytokines
Fibroblasts*
Humans*
Intercellular Adhesion Molecule-1*
Interleukin-1
Lymphocytes
RNA, Messenger
Tumor Necrosis Factor-alpha
Adhesives
Cytokines
Intercellular Adhesion Molecule-1
Interleukin-1
RNA, Messenger
Tumor Necrosis Factor-alpha