title: Expression profile of the matricellular protein osteopontin in primary open-angle glaucoma and the normal human eye.
abstract: PURPOSE. To characterize the role of osteopontin (OPN) in primary open-angle glaucoma (POAG) and normal eyes. METHODS. OPN quantification was performed by enzyme-linked immunosorbent assay in aqueous humor (AH) obtained from human donor eyes (POAG and normal) and surgical samples (POAG and elective cataract removal). OPN expression and localization in whole eye tissue sections and primary normal human trabecular meshwork (NTM) cells were studied by Western blot and immunohistochemistry. Latanoprost-free acid (LFA)-treated NTM cells were analyzed for OPN gene and protein expression. Intraocular pressure was measured by tonometry, and central corneal thickness was measured by optical coherence tomography in young OPN(-/-) and wild-type mice. RESULTS. OPN levels were significantly reduced in donor POAG AH compared with normal AH (0.54 ± 0.18 ng/μg [n = 8] vs. 0.77 ± 0.23 ng/μg [n = 9]; P = 0.039). A similar trend was observed in surgical AH (1.05 ± 0.31 ng/μg [n = 20] vs. 1.43 ± 0.88 ng/μg [n = 20]; P = 0.083). OPN was present in the trabecular meshwork, corneal epithelium and endothelium, iris, ciliary body, retina, vitreous humor, and optic nerve. LFA increased OPN gene expression, but minimal change in OPN protein expression was observed. No difference in intraocular pressure (17.5 ± 2.0 mm Hg [n = 56] vs. 17.3 ± 1.9 mm Hg [n = 68]) but thinner central corneal thickness (91.7 ± 3.6 μm [n = 50] vs. 99.2 ± 5.5 μm [n = 70]) was noted between OPN(-/-) and wild-type mice. CONCLUSIONS. OPN is widely distributed in the human eye and was found in lower concentrations in POAG AH. Reduction of OPN in young mice does not affect IOP.
authors: Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, USA.
authors: Uttio Roy
authors: UR
authors: Chowdhury
authors: Seung-Youn
authors: SY
authors: Jea
authors: Dong-Jin
authors: DJ
authors: Oh
authors: Douglas J
authors: DJ
authors: Rhee
authors: Michael P
authors: MP
authors: Fautsch
mesh_terms: D000369:Aged, 80 and over; D000818:Animals; D001082:Aqueous Humor / Q000378:metabolism; D015153:Blotting, Western; D004797:Enzyme-Linked Immunosorbent Assay; D005123:Eye / Q000378:metabolism*; D005260:Female; D020869:Gene Expression Profiling; D055786:Gene Knockout Techniques; D005902:Glaucoma, Open-Angle / Q000235:genetics* / Q000378:metabolism; D006031:Glycosylation; D006801:Humans; D007150:Immunohistochemistry; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018613:Microscopy, Confocal; D008875:Middle Aged; D053495:Osteopontin / Q000235:genetics* / Q000378:metabolism*; D014019:Tissue Donors; D041623:Tomography, Optical Coherence; D014065:Tonometry, Ocular; D014129:Trabecular Meshwork / Q000378:metabolism; D055815:Young Adult
chemical_list: D053495:Osteopontin