Limits...
Bioinformatic and statistical analysis of the optic nerve head in a primate model of ocular hypertension.

Kompass KS, Agapova OA, Li W, Kaufman PL, Rasmussen CA, Hernandez MR - BMC Neurosci (2008)

Bottom Line: Laser scarification of the trabecular meshwork of cynomolgus macaques produced elevated intraocular pressure that was monitored over time and led to varying degrees of damage in different samples.We validated a subset of differentially expressed genes using qRT-PCR, immunohistochemistry, and immuno-enriched astrocytes from healthy and glaucomatous human donors.These genes have previously defined roles in axonal outgrowth, immune response, cell motility, neuroprotection, and extracellular matrix remodeling.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St, Louis, MO 63110, USA. kompass@vision.wustl.edu

ABSTRACT

Background: The nonhuman primate model of glaucomatous optic neuropathy most faithfully reproduces the human disease. We used high-density oligonucleotide arrays to investigate whole genome transcriptional changes occurring at the optic nerve head during primate experimental glaucoma.

Results: Laser scarification of the trabecular meshwork of cynomolgus macaques produced elevated intraocular pressure that was monitored over time and led to varying degrees of damage in different samples. The macaques were examined clinically before enucleation and the myelinated optic nerves were processed post-mortem to determine the degree of neuronal loss. Global gene expression was examined in dissected optic nerve heads with Affymetrix GeneChip microarrays. We validated a subset of differentially expressed genes using qRT-PCR, immunohistochemistry, and immuno-enriched astrocytes from healthy and glaucomatous human donors. These genes have previously defined roles in axonal outgrowth, immune response, cell motility, neuroprotection, and extracellular matrix remodeling.

Conclusion: Our findings show that glaucoma is associated with increased expression of genes that mediate axonal outgrowth, immune response, cell motility, neuroprotection, and ECM remodeling. These studies also reveal that, as glaucoma progresses, retinal ganglion cell axons may make a regenerative attempt to restore lost nerve cell contact.

Show MeSH

Related in: MedlinePlus

Stathmin protein expression in experimental glaucoma in sagittal sections of the ONH (Macaque #5; Supplemental Table 3). (A) Stathmin (red) is not expressed in the retinal ganglion cell layer (GCL) or in the retinal nerve fiber layer (NFL) in the retina of normal monkeys. GFAP stains retinal astrocytes (green). (B) In ExpG, stathmin staining is present in the nerve fiber layer presumably in axons. Stathmin does not co-localize with GFAP+ retinal astrocytes in the nerve fiber layer. Some cells bearing processes stain strongly for stathmin in the nerve fiber layer (arrows). Magnification bar: A = 25 μm; B = 40 μm. (C, D) Co-localization of stathmin and GFAP in astrocytes of the glial columns (GC) in the optic nerve head in normal optic nerve head and ExpG. Axons in the nerve bundles (NB) also exhibit staining for stathmin. Note that cells in the lamina cribrosa (LC) are devoid of staining for stathmin. Magnification bar = 55 μm. (E) Stathmin stains oligodendrocytes in the post-laminar optic nerve in normal optic nerves. (F) Stathmin-labeled bipolar oligodendrocytes (arrows) are abundant in the post-laminar optic nerve in ExpG. Insert shows co-localization of APC (green), a marker of oligodendrocytes cell bodies and non-myelinating processes with stathmin in the post laminar optic nerve. Magnification bar = 35 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC2567987&req=5

Figure 4: Stathmin protein expression in experimental glaucoma in sagittal sections of the ONH (Macaque #5; Supplemental Table 3). (A) Stathmin (red) is not expressed in the retinal ganglion cell layer (GCL) or in the retinal nerve fiber layer (NFL) in the retina of normal monkeys. GFAP stains retinal astrocytes (green). (B) In ExpG, stathmin staining is present in the nerve fiber layer presumably in axons. Stathmin does not co-localize with GFAP+ retinal astrocytes in the nerve fiber layer. Some cells bearing processes stain strongly for stathmin in the nerve fiber layer (arrows). Magnification bar: A = 25 μm; B = 40 μm. (C, D) Co-localization of stathmin and GFAP in astrocytes of the glial columns (GC) in the optic nerve head in normal optic nerve head and ExpG. Axons in the nerve bundles (NB) also exhibit staining for stathmin. Note that cells in the lamina cribrosa (LC) are devoid of staining for stathmin. Magnification bar = 55 μm. (E) Stathmin stains oligodendrocytes in the post-laminar optic nerve in normal optic nerves. (F) Stathmin-labeled bipolar oligodendrocytes (arrows) are abundant in the post-laminar optic nerve in ExpG. Insert shows co-localization of APC (green), a marker of oligodendrocytes cell bodies and non-myelinating processes with stathmin in the post laminar optic nerve. Magnification bar = 35 μm.

Mentions: Labeling with stathmin (STMN) antibody revealed specific upregulation of STMN in ExpG. Within the retina, STMN immunoreactivity was very low in normal eyes (Figure 4A). In ExpG, STMN was detected in the nerve fiber layer and in few GFAP-negative process-bearing cells. Retinal ganglion cells and retinal astrocytes did not exhibit STMN immunoreactivity (Figure 4B). In the prelaminar optic nerve head, low levels of STMN were expressed in the glial columns and in the nerve bundles in both control and ExpG samples without obvious differences (Figure 4C, D). In both control and ExpG, STMN expression was absent from the lamina cribrosa and present in the optic nerve proper. Oligodendrocytes exhibited strong immunoreactivity for STMN in the somata and cell processes (Figure 4E, F). In ExpG, many oligodendrocytes exhibited bipolar shape with long processes (Figure 4F). In control eyes STMN stained the nerve bundles, but not in ExpG (Figure 4E, F). Positive staining with adenomatous polyposis coli (APC) identified these cells as oligodendrocytes (inset, Figure 4F). STMN was not expressed in GFAP+ astrocytes in the myelinated nerve.


Bioinformatic and statistical analysis of the optic nerve head in a primate model of ocular hypertension.

Kompass KS, Agapova OA, Li W, Kaufman PL, Rasmussen CA, Hernandez MR - BMC Neurosci (2008)

Stathmin protein expression in experimental glaucoma in sagittal sections of the ONH (Macaque #5; Supplemental Table 3). (A) Stathmin (red) is not expressed in the retinal ganglion cell layer (GCL) or in the retinal nerve fiber layer (NFL) in the retina of normal monkeys. GFAP stains retinal astrocytes (green). (B) In ExpG, stathmin staining is present in the nerve fiber layer presumably in axons. Stathmin does not co-localize with GFAP+ retinal astrocytes in the nerve fiber layer. Some cells bearing processes stain strongly for stathmin in the nerve fiber layer (arrows). Magnification bar: A = 25 μm; B = 40 μm. (C, D) Co-localization of stathmin and GFAP in astrocytes of the glial columns (GC) in the optic nerve head in normal optic nerve head and ExpG. Axons in the nerve bundles (NB) also exhibit staining for stathmin. Note that cells in the lamina cribrosa (LC) are devoid of staining for stathmin. Magnification bar = 55 μm. (E) Stathmin stains oligodendrocytes in the post-laminar optic nerve in normal optic nerves. (F) Stathmin-labeled bipolar oligodendrocytes (arrows) are abundant in the post-laminar optic nerve in ExpG. Insert shows co-localization of APC (green), a marker of oligodendrocytes cell bodies and non-myelinating processes with stathmin in the post laminar optic nerve. Magnification bar = 35 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2567987&req=5

Figure 4: Stathmin protein expression in experimental glaucoma in sagittal sections of the ONH (Macaque #5; Supplemental Table 3). (A) Stathmin (red) is not expressed in the retinal ganglion cell layer (GCL) or in the retinal nerve fiber layer (NFL) in the retina of normal monkeys. GFAP stains retinal astrocytes (green). (B) In ExpG, stathmin staining is present in the nerve fiber layer presumably in axons. Stathmin does not co-localize with GFAP+ retinal astrocytes in the nerve fiber layer. Some cells bearing processes stain strongly for stathmin in the nerve fiber layer (arrows). Magnification bar: A = 25 μm; B = 40 μm. (C, D) Co-localization of stathmin and GFAP in astrocytes of the glial columns (GC) in the optic nerve head in normal optic nerve head and ExpG. Axons in the nerve bundles (NB) also exhibit staining for stathmin. Note that cells in the lamina cribrosa (LC) are devoid of staining for stathmin. Magnification bar = 55 μm. (E) Stathmin stains oligodendrocytes in the post-laminar optic nerve in normal optic nerves. (F) Stathmin-labeled bipolar oligodendrocytes (arrows) are abundant in the post-laminar optic nerve in ExpG. Insert shows co-localization of APC (green), a marker of oligodendrocytes cell bodies and non-myelinating processes with stathmin in the post laminar optic nerve. Magnification bar = 35 μm.
Mentions: Labeling with stathmin (STMN) antibody revealed specific upregulation of STMN in ExpG. Within the retina, STMN immunoreactivity was very low in normal eyes (Figure 4A). In ExpG, STMN was detected in the nerve fiber layer and in few GFAP-negative process-bearing cells. Retinal ganglion cells and retinal astrocytes did not exhibit STMN immunoreactivity (Figure 4B). In the prelaminar optic nerve head, low levels of STMN were expressed in the glial columns and in the nerve bundles in both control and ExpG samples without obvious differences (Figure 4C, D). In both control and ExpG, STMN expression was absent from the lamina cribrosa and present in the optic nerve proper. Oligodendrocytes exhibited strong immunoreactivity for STMN in the somata and cell processes (Figure 4E, F). In ExpG, many oligodendrocytes exhibited bipolar shape with long processes (Figure 4F). In control eyes STMN stained the nerve bundles, but not in ExpG (Figure 4E, F). Positive staining with adenomatous polyposis coli (APC) identified these cells as oligodendrocytes (inset, Figure 4F). STMN was not expressed in GFAP+ astrocytes in the myelinated nerve.

Bottom Line: Laser scarification of the trabecular meshwork of cynomolgus macaques produced elevated intraocular pressure that was monitored over time and led to varying degrees of damage in different samples.We validated a subset of differentially expressed genes using qRT-PCR, immunohistochemistry, and immuno-enriched astrocytes from healthy and glaucomatous human donors.These genes have previously defined roles in axonal outgrowth, immune response, cell motility, neuroprotection, and extracellular matrix remodeling.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St, Louis, MO 63110, USA. kompass@vision.wustl.edu

ABSTRACT

Background: The nonhuman primate model of glaucomatous optic neuropathy most faithfully reproduces the human disease. We used high-density oligonucleotide arrays to investigate whole genome transcriptional changes occurring at the optic nerve head during primate experimental glaucoma.

Results: Laser scarification of the trabecular meshwork of cynomolgus macaques produced elevated intraocular pressure that was monitored over time and led to varying degrees of damage in different samples. The macaques were examined clinically before enucleation and the myelinated optic nerves were processed post-mortem to determine the degree of neuronal loss. Global gene expression was examined in dissected optic nerve heads with Affymetrix GeneChip microarrays. We validated a subset of differentially expressed genes using qRT-PCR, immunohistochemistry, and immuno-enriched astrocytes from healthy and glaucomatous human donors. These genes have previously defined roles in axonal outgrowth, immune response, cell motility, neuroprotection, and extracellular matrix remodeling.

Conclusion: Our findings show that glaucoma is associated with increased expression of genes that mediate axonal outgrowth, immune response, cell motility, neuroprotection, and ECM remodeling. These studies also reveal that, as glaucoma progresses, retinal ganglion cell axons may make a regenerative attempt to restore lost nerve cell contact.

Show MeSH
Related in: MedlinePlus