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Inflammatory proteases in chronic otitis externa

Patrick J Antonelli1, Gregory S Schultz, John S Cantwell

  • 1Department of Otolaryngology, University of Florida, Gainesville, Florida 32610-0264, USA. antonpj@ent.ufl.edu

The Laryngoscope
|April 5, 2005
PubMed
Abstract

Insights

Matrix metalloproteinases (MMP) and human neutrophil elastase (HNE) are elevated in chronic otitis externa (COE). Protease inhibitors ilomastat and recombinant alpha 1-antitrypsin (rAAT) show potential for treating COE.

Area of Science:

  • Otolaryngology
  • Dermatology
  • Biochemistry

Background:

  • Proteases, including matrix metalloproteinases (MMP) and human neutrophil elastase (HNE), are implicated in chronic inflammatory skin conditions.
  • Inhibiting these proteases has shown therapeutic promise for skin diseases.

Purpose of the Study:

  • To quantify MMP and HNE activity in chronic otitis externa (COE).
  • To assess the efficacy of protease inhibitors, recombinant alpha 1-antitrypsin (rAAT) and ilomastat, in reducing MMP and HNE activity in COE.

Main Methods:

  • A prospective, ex vivo study involving 25 ears with COE and 34 control ears.
  • Ear canal washes were collected and analyzed for MMP and HNE activities.
  • Inhibitory effects of rAAT and ilomastat were evaluated.

Main Results:

  • MMP and HNE levels were significantly higher in COE ears compared to controls (P = .0057 and .0112, respectively).
  • Elevated MMP activity (>3 mAU/minute) was found in 30% of COE cases versus 0% of controls (P = .0270).
  • Significantly higher HNE activity (>3 mAU/minute) was observed in 77% of COE cases compared to 7% of controls (P < .0001).
  • Ilomastat inhibited 60% of MMP activity, and rAAT inhibited 98% of HNE activity in COE ears.

Conclusions:

  • Chronic otitis externa (COE) exhibits elevated levels of MMP and HNE proteases.
  • The protease inhibitors ilomastat and rAAT effectively reduced MMP and HNE activity, respectively, in COE.
  • Further investigation into the therapeutic potential of these protease inhibitors for COE is warranted.

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