In-office testing of matrix metalloproteinase-9 (MMP-9) levels is increasingly seen as diagnostically useful in dry eye patients. Now, a new study in Eye & Contact Lens reports that overexpression of MMP-9 may play a significant role in ocular surface disorders beyond dry eye as well, and this finding could be helpful in creating new therapies to treat these conditions.
The investigation also found the inhibition of MMP-9 frequently led to improvements in ocular surface disease.
Researchers conducted a literature review of MMP-9 all the way back to 1995 using the US National Library of Medicine search database. They reported MMP-9 overexpression was found in both in vitro and in vivo models of dry eye disease, corneal ulcers, microbial keratitis, corneal neovascularization, ultraviolet light-induced radiation and a host of additional ocular surface pathologies.
Additionally, the study observed a trend of MMP-9’s involvement in an intricate signal transduction cascade that included induction by many pro-inflammatory molecules including interleukin-1, tumor necrosis factor alpha, nuclear factor kappa light chain enhancer of activated B cells, platelet-activating factor, activator protein 1 and transforming growth factor beta.
The investigators also found MMP-9 expression tended to be blunted by a diverse array of molecular factors, such as tissue inhibitors of metalloproteinases, cyclosporine A, PES-103, epigalloccatechin-3-gallate, N-acetylcysteine, ascorbate, tetracyclines and corticosteroids.
|Jamerson EC, Elhusseiny AM, ElSheikh RH. Role of matrix metalloproteinase 9 in ocular surface disorders. Eye Contact Lens. February 14, 2020. [Epub ahead of print].|