Investigation of the Neuroprotective Effect of Riluzole on Matrix Metalloproteinases in an Experimental Model of Glaucoma

Purpose: To investigate the neuroprotective effect of riluzole through matrix metalloproteinase-2 (MMP-2) and MMP-9 in rats, in an experimental glaucoma model. Methods: A total of 28 Wistar albino rats, 3-4 months old, weighing 250-300 g, were divided into four groups; Group I (control), Group II (glaucoma), Group III (glaucoma + corn oil + dimethyl sulfoxide (DMSO), and Group IV (glaucoma + corn oil + DMSO + riluzole). A glaucoma model was created by episcleral vein cauterization in the left eyes of Group II, III, and IV subjects. After the formation of the model, daily intraperitoneal riluzole (5 mg/kg) administration was started. At the end of 7 weeks, retinal tissues were taken and some parts of them were stained with hematoxylin and eosin for histopathological examinations. In the other part, MMP-2 and MMP-9 expressions were determined using real-time quantitative PCR and immunohistochemical techniques. Results: As a result, a statistically significant increase in intraocular pressures (IOP) was found in Groups II, III, and IV when compared with the control eyes after 7 weeks (P < 0.001). There was a decrease in IOP in the riluzole group compared to the glaucoma group. Expression levels in both genes decreased slightly with riluzole administration. In the histopathological evaluation of the groups, it was observed that there were no significant differences between the findings of degeneration in ganglion cells, hemorrhage, and differentiation in layers. Conclusions: MMP-2 and MMP-9 exhibited decreased expression levels in both Group III (glaucoma + corn oil + DMSO) and Group IV (glaucoma + corn oil + DMSO + 5 mg/kg riluzole) compared to the glaucoma groups in Group II. Given that both Group III and Group IV received injections of corn oil + DMSO, this conclusion was drawn. Keywords: Glaucoma, Intraocular pressure, Matrix metalloproteinase-2, Matrix metalloproteinase-9, Neuroprotection, Riluzole