Mechanical strain inhibits repair of airway epithelium in vitro

Ushma Savla, Christopher Waters

Research output: Contribution to journalArticle

59 Citations (Scopus)

Abstract

The repair of airway epithelium after injury is crucial in restoring epithelial barrier integrity. Although the airway epithelium is stretched and compressed due to changes in both circumferential and longitudinal dimensions during respiration and may be overdistended during mechanical ventilation, the effect of cyclic strain on the repair of epithelial wounds is unknown. Human and cat airway epithelial cells were cultured on flexible membranes, wounded by scraping with a metal spatula, and subjected to cyclic strain using the Flexercell Strain Unit. Because the radial strain profile in the wells was nonuniform, we compared closure in regions of elongation and compression within the same well. Both cyclic elongation and cyclic compression significantly slowed repair, with compression having the greatest effect. This attenuation was dependent upon the time of relaxation (TR) during the cycle. When wells were stretched at 10 cycles/min (6 s/cycle) with TR = 5 s, wounds closed similarly to wounds in static wells, whereas in wells with TR = 1 s, significant inhibition was observed. As the TR during cycles increased (higher TR), wounds closed faster. We measured the effect of strain at various TRs on cell area and centroid-centroid distance (CD) as a measure of spreading and migration. While cell area and CD in static wells significantly increased over time, the area and CD of cells in the elongated regions did not change. Cells in compressed regions were significantly smaller, with significantly lower CD. Cell area and CD became progressively larger with increasing TR. These results suggest that mechanical strain inhibits epithelial repair.

Original languageEnglish (US)
JournalAmerican Journal of Physiology - Lung Cellular and Molecular Physiology
Volume274
Issue number6 18-6
StatePublished - Jun 1 1998

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Epithelium
Wounds and Injuries
In Vitro Techniques
Artificial Respiration
Respiration
Cats
Epithelial Cells
Metals
Membranes

All Science Journal Classification (ASJC) codes

  • Physiology
  • Pulmonary and Respiratory Medicine
  • Physiology (medical)
  • Cell Biology

Cite this

Mechanical strain inhibits repair of airway epithelium in vitro. / Savla, Ushma; Waters, Christopher.

In: American Journal of Physiology - Lung Cellular and Molecular Physiology, Vol. 274, No. 6 18-6, 01.06.1998.

Research output: Contribution to journalArticle

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