Monday, July 20, 2009

Abstract: MMP9 as a dry eye marker

Production and activity of matrix metalloproteinase-9 on the ocular surface increase in dysfunctional tear syndrome.
Invest Ophthalmol Vis Sci. 2009 Jul;50(7):3203-9. Epub 2009 Feb 28.
Chotikavanich S, de Paiva CS, Li de Q, Chen JJ, Bian F, Farley WJ, Pflugfelder SC.
Department of Ophthalmology, Ocular Surface Center, Cullen Eye Institute, Baylor College of Medicine, Houston, Texas 77030, USA.

PURPOSE: To evaluate production and activity of metalloproteinase (MMP)-9 on the ocular surface of patients with dysfunctional tear syndrome (DTS) and determine any correlation between MMP-9 activity and clinical parameters.

METHODS: Forty-six patients with newly diagnosed DTS and 18 control subjects were recruited. Complete ocular surface examinations were performed. Tear MMP-9 activity was assessed with an MMP-9 activity assay in 1 microL of unstimulated tear fluid. Using conjunctival epithelial cells from 19 patients with DTS and 16 controls, levels of MMP-9 and its regulating cytokine mRNA transcripts were evaluated by semiquantitative real-time PCR.

RESULTS: Each of four DTS severity-based groups had significantly higher mean MMP-9 activities than did the control group, which was 8.39 +/- 4.70 ng/mL. The DTS4 group had the highest MMP-9 activity (381.24 +/- 142.83 ng/mL), for which the mean was significantly higher than that of other DTS groups. In addition, patients with DTS had significantly higher levels of IL-1beta, IL-6, TNF-alpha, and TGF-beta1 mRNA transcripts in their conjunctival epithelia than did the control subjects. Tear MMP-9 activities showed significant correlation with symptom severity scores, decreased low-contrast visual acuity, fluorescein tear break-up time, corneal and conjunctival fluorescein staining, topographic surface regularity index (SRI), and percentage area of abnormal superficial corneal epithelia by confocal microscopy.

CONCLUSIONS: Tear MMP-9 activity was significantly higher in patients with DTS. This activity was associated with increased mRNA expression of MMP-9 and its regulating genes and correlated strongly with clinical parameters. MMP-9 appears to be a potentially useful biomarker for diagnosing, classifying, and monitoring DTS.

1 comment:

Julia said...

I'm a 63-yr-old female with ocular rosacea (my self-diagnosis--my ophthal. calls it dry eye, meibomian gland dysfunction,corneal erosions, etc), facial rosacea, and osteoarthritis of the hip. Took isotretinoin(low dose)for several months and noticed improvement in my facial AND ocular rosacea. Recently I've been taking meloxicam sporadically for osteoarthritis and noticed that it helps incipient rhinophyma (from the rosacea). Both meloxicam and isotretinoin suppress MMP-9. From what I've gathered through my own "data mining," MMP-9 is a common "bad guy" in many cases of dry eye, rosacea, and osteoarthritis

SO, was excited to read today that a small biotech eye product company (Alacrity)on the west coast is well along in developing a doxycycline eye drop to suppress "bad guy" MMP-9. Hope it is approved soon and we can obtain this from our ophthal.instead of being offered restasis!