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Cathepsin K expression is diminished in infants with bronchopulmonary dysplasia

Jonni Knaapi1, Heikki Lukkarinen, Riku Kiviranta

  • 1Research Centre of Applied and Preventive Cardiovascular Medicine, University of Turku, FIN-20520 Turku, Finland. jonni.knaapi@utu.fi

Acta Paediatrica (Oslo, Norway : 1992)
|September 20, 2006
PubMed

Insights

Cathepsin K expression was lower in premature infants who developed bronchopulmonary dysplasia (BPD). This finding suggests insufficient cathepsin K may predispose infants to lung fibrosis.

Area of Science:

  • Biochemistry
  • Neonatal Medicine
  • Pulmonology

Background:

  • Bronchopulmonary dysplasia (BPD) is a chronic lung disorder in premature infants.
  • Cathepsin K is a collagenolytic enzyme implicated in tissue remodeling.

Purpose of the Study:

  • To measure cathepsin K expression in premature infants with and without BPD.
  • To investigate the role of cathepsin K in the pathogenesis of BPD.

Main Methods:

  • Tracheal aspirate samples were collected from premature infants.
  • Cathepsin K expression levels were measured over time.

Main Results:

  • Cathepsin K expression was significantly lower in infants who developed BPD compared to controls.
  • This difference was observed at 9-13 days of life, but not earlier.

Conclusions:

  • Lower pulmonary cathepsin K expression may increase the risk of developing BPD.
  • Insufficient cathepsin K may predispose premature lungs to pulmonary fibrosis.
Abstract

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