The Role Of Mmp-9 In Keratoconus

Keratoconus is a progressive corneal disease characterized by the thinning of the cornea and turning into a conical shape  rather than its normal, spherical curvature. While the exact cause of keratoconus remains unknown, recent studies found correlation between keratoconus and elevated levels of Matrix Metalloproteinase 9 (MMP-9) in human tears. Many studies have shown MMP-9 higher concentrations in the tears of individuals with keratoconus compared to those with healthy corneas. In this article, we aim to gain a better understanding of correlation MMP-9 elevation in tear between keratoconus and healthy population.

The study consisted of two phases: The first phase aimed to detect increased MMP-9 levels in tears in patients with keratoconus compared to a control group. The second phase aimed to determine the level of MMP-9 in tears and its association with the stage of keratoconus. The study was double blind, tear collection was performed in an examination room offic, the detection and further quantitative analysis of MMP-9 levels was done with enzyme-linked immunosorbent assay (ELISA). 

In every phase two groups were examined:

-Group 1: Anterior curvature greater than or equal to 46D, back elevation more than 20, and pachymetry less than 430 microns.

 -Control Group: Anterior curvature less than or equal to 46D, back elevation less than 10, and pachymetry greater than or equal to 520 microns.

First phase: A total of 120 patients (120 eyes) were included: the Group 1 Included 60 patients (60 eyes) with stages 1-3 of keratoconus. The Control Group consisted of 60 patients (60 eyes) from the healthy population.

Second Phase: This phase involved 150 patients (150 eyes): Group 1 involved 75 patients (75 eyes) with stages 1-3 of keratoconus. The Control Group  Included 75 patients (75 eyes) from the healthy population.

In the first phase of the study, MMP-9 was detected in 58 patients out of 60 with keratoconus (Group I) compared to the control group where only in one  patient out of 60 tear MMP-9 was detected. In the second phase the average level of MMP-9 in tears was 40.640 in the Group 1, otherwise the same level of MMP-9 was 0.181 in  the control group. Among the participants in Group I, the elevation of MMP-9 was notably associated with the severity of keratoconus, with higher levels observed in more advanced stages of the disease. These findings suggest a strong correlation between keratoconus and elevated MMP-9 levels in tears.

The results of this study provide a clear association between keratoconus and elevated MMP-9 levels in tears. This finding suggests that MMP-9 may play a key role in the pathogenesis and progression of keratoconus. Moreover, based on correlation observed between the severity of keratoconus and MMP-9 levels MMP-9 measurement could be a diagnostic and prognostic marker. These findings open new paths for further research into the mechanistic relationship between MMP-9 and keratoconus, as well as to develop a targeted therapeutic treatment for keratoconus. Further studies are essential to explore the clinical implications of these findings in greater depth.