Induction of hyaluronan metabolism after mechanical injury of human peritoneal mesothelial cells in vitro.
BACKGROUND
Hyaluronan (HA) is an important extracellular matrix component that is involved in cell movement and tissue repair. In vertebrates, HA synthase genes (HAS 1, HAS 2, and HAS 3) that control the synthesis of HA have been identified. In this article, we investigated HA synthesis in the response of human peritoneal mesothelial cells (HPMCs) to injury.


METHODS
The expression of HAS 1, HAS 2, and HAS 3 mRNA and the synthesis of [(3)H]-labeled HA were examined in an in vitro model of peritoneal mesothelial cell damage. The staining for uridine diphosphoglucose dehydrogenase, a key enzyme in the synthesis of HA, and biotinylated HA-binding protein was used to determine the cellular location of HA synthesis and its site of deposition.


RESULTS
Growth-arrested human HPMCs expressed low levels of mRNA for HAS 2 and HAS 3 but not HAS 1. Following injury to the monolayer, HAS 2 was up-regulated by 6 hours, reaching maximal expression between 12 and 24 hours. In contrast, the expression of HAS 3 was down-regulated. During the same time period, synthesis of HA was increased in the injured monolayer. This synthetic activity appeared to be restricted to cells at the edge of the wound and to cells entering the wound. In a separate series of experiments, the addition of HA to the injured monolayer at a concentration range found in peritoneal fluid (50 to 3300 ng/mL) increased the migration of cells into the wound in a dose-dependent manner.


CONCLUSIONS
These studies provide evidence that HA is an important component of peritoneal mesothelial cell migration. The results also suggest that in this process, there is differential regulation of HAS gene expression and that the synthesis of HA is limited to cells located at the leading edge of the wound.
Yung
S
S
Institute of Nephrology, University of Wales College of Medicine, Wales, United Kingdom.
Thomas
G J
GJ
Davies
M
M
D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D004848:Epithelium / Q000293:injuries / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D014453:Glucuronosyltransferase / Q000378:metabolism; D016695:Glycosyltransferases; D006801:Humans; D000076002:Hyaluronan Synthases; D006820:Hyaluronic Acid / Q000096:biosynthesis / Q000378:metabolism*; D008565:Membrane Proteins; D010537:Peritoneum / Q000293:injuries* / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D013997:Time Factors; D014018:Tissue Distribution; D014166:Transferases; D014945:Wound Healing / Q000187:drug effects; D014947:Wounds and Injuries / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D029867:Xenopus Proteins
D008565:Membrane Proteins; D029867:Xenopus Proteins; D006820:Hyaluronic Acid; D014166:Transferases; D016695:Glycosyltransferases; D014453:Glucuronosyltransferase; C056944:HAS1 protein, Xenopus; C101754:HAS2 protein, human; C105458:HAS3 protein, human; C491096:Has2 protein, Xenopus; D000076002:Hyaluronan Synthases