Metalloproteinase 9 and TIMP-1 expression in retina and optic nerve in absolute angle closure glaucoma.
OBJECTIVE
Glaucoma is one of the most important reason causes of the blindness, associated with retinal ganglion cells (RGC) death. This process is not fully understood, however apoptosis due to hypoxia is one of the most important processes leading to RGC death. Glaucomatous optic neuropathy is characterized by remodeling of the extracellular matrix due to metalloproteinase activation, which leads to loss of RGC and axons at the optic nerve head. The aim of the study was to evaluate metalloproteinase 9 (MMP-9) and tissue metalloproteinase inhibitor-1 (TIMP-1) expression in the retinal ganglion cells and optic nerve axons in 33 eyes with absolute primary glaucoma.


METHODS
To evaluate MMP-9 and TIMP-1 expression primary polyclonal goat antibodies against MMP-9 and TIMP-1 were used. The control group was composed of 8 cases of eyes enucleated and fixed in the first day after trauma.


RESULTS
MMP-9 expression was observed in retinal ganglion cells and in the inner nuclear layer of the retina in all the examined cases. In 28 out of 33 glaucomatous eyes, MMP-9 expression was observed in the proliferating glial cells surrounding the optic nerve axons. TIMP-1 expression was observed in 10 out of 33 glaucomatous eyes, only in retinal ganglion cells. None of the examined injured eyes showed MMP-9 and TIMP-1 expression.


CONCLUSIONS
MMP-9 activation rather than TIMP-1 may by associated with the pathomechanism of retinal ganglion cell and optic nerve damage in absolute glaucoma.
Department of Ophthalmology, Medical University of Bialystok, Bialystok, Poland.
Renata
R
Zalewska
Department of Medical Pathomorphology, Medical University of Bialystok, Bialystok, Poland. Electronic address: joannareszec@gmail.com.
Joanna
J
Reszeć
Department of Medical Pathomorphology, Medical University of Bialystok, Bialystok, Poland.
Wojciech
W
Kisielewski
Department of Ophthalmology, Medical University of Bialystok, Bialystok, Poland.
Zofia
Z
Mariak
D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000201:enzymology* / Q000473:pathology; D006801:Humans; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D008875:Middle Aged; D009898:Optic Disk / Q000201:enzymology / Q000473:pathology; D009900:Optic Nerve / Q000201:enzymology* / Q000473:pathology; D012160:Retina / Q000201:enzymology* / Q000473:pathology; D012165:Retinal Ganglion Cells / Q000201:enzymology / Q000473:pathology; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism*
D019715:Tissue Inhibitor of Metalloproteinase-1; C579270:MMP9 protein, human; D020780:Matrix Metalloproteinase 9
Glaucoma; MMP-9; Optic nerve; Retina; TIMP-1