Individualized Significance of 24-Hour Intraocular Pressure Curves for Therapeutic Decisions in Primary Chronic Open-Angle Glaucoma Patients.

PURPOSE: Diagnostic 24-hour intraocular pressure curves (IPC) are well established in the management of glaucoma. However, objective criteria for the IPC indication are lacking. The aim of this study was to evaluate the impact of individual patient characteristics and glaucoma-related parameters on therapy decisions after IPC and thus examine their relevance for glaucoma management. PATIENTS AND METHODS: Retrospective analysis of adult primary open-angle glaucoma (POAG) patients who underwent an IPC (≥6 IOP measurements in 24 hours). The main exclusion criterion was previous IOP-lowering surgery. IPC-dependent (eg, mean and peak IOP) and IPC-independent parameters (eg, perimetry, RNFL thickness) were analyzed in relation to the therapeutic decision after IPC. Further, these parameters were compared in patient subgroups based on age, glaucoma stage, or therapy intensity. RESULTS: A total of 101 eyes of 101 patients were included. In general, mean and peak IOP were elevated in patients with a therapeutic change after IPC. These subjects presented differences of IPC-independent parameters (eg, IOP at admission, RNFL thickness, glaucoma stage). Regression analysis results suggested a predictive role of IPC-independent parameters for IPC therapeutic decisions. In subgroups of patients of older age or advanced glaucoma, IPC-independent parameters did not correlate with therapeutic decisions after IPC. CONCLUSION: These results support the relevance of IPC in the therapeutic management of POAG. Moreover, the study promotes a personalized classification of patients using selected glaucoma characteristics to objectivize their individual benefit from IPC. Further prospective studies are needed to verify the utility of these parameters and IPC in the management of glaucoma.

Age-related distribution and potential role of SNCB in topographically different retinal areas of the common marmoset Callithrix jacchus, including the macula.

Evidence of an age-related increase of ß-synuclein (SNCB) in several parts of the visual system including the retina has been reported. SNCB is thought to function as an antagonist of α-synuclein in neurodegenerative diseases, but the exact role of SNCB remains unclear. The presented work studies two different aspects of the onset and role of SNCB in the retinal pigment epithelium (RPE). First, the topographical and intracellular distributions of SNCB in the RPE of non-human marmoset monkey (Callithrix jacchus) were evaluated in paraffin-embedded eyes and RPE whole mounts from different developmental stages (neonatal, adolescent, and adult). Thus, revealed distinct lifetime-related alterations of the topographical and intracellular distributions of SNCB in the primate macula compared to the retinal periphery. Furthermore, the function and influences of SNCB on ARPE-19 cells and primary porcine RPE (ppRPE) cells were characterized by exposing these cells with recombinant SNCB (rSNCB) at different concentrations. Moreover, apoptosis, protein- and mRNA-expression levels of factors of the p53/MDM2 signaling cascade and inflammation- and oxidation-related genes were investigated. The observed dose-depended decreased apoptosis rates together with the PLD2 mediated activation of the p53 pathway promotes senescence-related processes in SNCB exposed common ARPE-19 cells from human origin. Further, increased HMOX1 and NOX4 levels indicate increased oxidative stress and inflammatory responses triggered by SNCB. The obtained differences in the distribution of SNCB in primate RPE together with alterations of cellular functions in rSNCB-exposed RPE cells (e.g., ARPE-19, ppRPE) support SNCB-related effects like inflammatory response and stress-related properties on RPE over lifetime. The possible functional relevance of SNCB in physiological aging converting into a pathophysiological condition should be investigated in further studies.

Age-related Beta-synuclein Alters the p53/Mdm2 Pathway and Induces the Apoptosis of Brain Microvascular Endothelial Cells In Vitro.

Increased ß-synuclein (Sncb) expression has been described in the aging visual system. Sncb functions as the physiological antagonist of α-synuclein (Snca), which is involved in the development of neurodegenerative diseases, such as Parkinson's and Alzheimer's diseases. However, the exact function of Sncb remains unknown. The aim of this study was to elucidate the age-dependent role of Sncb in brain microvascular endothelial cells (BMECs). BMECs were isolated from the cortices of 5- to 9-d-old Sprague-Dawley rats and were cultured with different concentrations of recombinant Sncb (rSncb) up to 72 h resembling to some degree age-related as well as pathophysiological conditions. Viability, apoptosis, expression levels of Snca, and the members of phospholipase D2 (Pld2)/ p53/ Mouse double minute 2 homolog (Mdm2)/p19(Arf) pathway, response in RAC-alpha serine/threonine-protein kinase (Akt), and stress-mediating factors such as heme oxygenase (decycling) 1 (Hmox) and Nicotinamide adenine dinucleotide phosphate oxygenase 4 (Nox4) were examined. rSncb-induced effects were confirmed through Sncb small interfering RNA (siRNA) knockdown in BMECs. We demonstrated that the viability decreases, while the rate of apoptosis underly dose-dependent alterations. For example, apoptosis increases in BMECs following the treatment with higher dosed rSncb. Furthermore, we observed a decrease in Snca immunostaining and messenger RNA (mRNA) levels following the exposure to higher rScnb concentrations. Akt was shown to be downregulated and pAkt upregulated by this treatment, which was accompanied by a dose-independent increase in p19(Arf) levels and enhanced intracellular Mdm2 translocation in contrast to a dose-dependent p53 activation. Moreover, Pld2 activity was shown to be induced in rSncb-treated BMECs. The expression of Hmox and Nox4 after Sncb treatment was altered on BEMCs. The obtained results demonstrate dose-dependent effects of Sncb on BMECs in vitro. For example, the p53-mediated and Akt-independent apoptosis together with the stress-mediated response of BMECs related to exposure of higher SNCB concentrations may reflect the increase in Sncb with duration of culture as well as its impact on cell decay. Further studies, expanding on the role of Sncb, may help understand its role in the neurodegenerative diseases.

Ocular Hypotony in Patients With Juvenile Idiopathic Arthritis-Associated Uveitis.

PURPOSE: To analyze occurrence, risk factors, and course of ocular hypotony (OH) in juvenile idiopathic arthritis-associated uveitis (JIAU). DESIGN: Cohort study. METHODS: Epidemiologic and ophthalmologic data at baseline and during follow-up of JIAU patients with and without ocular hypotony were evaluated. RESULTS: OH developed in 57 of the 365 JIAU patients during the follow-up (mean 4.5 ± 3.5 years). In 40 patients with follow-up ≥12 months, OH was unrelated to previous ocular surgery: risk factors at baseline (univariate logistic regression analysis) included longer total duration of uveitis (odds ratio [OR] 1.13, P < .001), bilateral uveitis (OR 3.51, P = .009), low visual acuity (OR 5.1, P = .001), high laser-flare (LF) values (OR 1.74, P = .01), and presence of posterior synechiae (OR 3.28, P = .004). Increased anterior chamber (AC) cell and LF values were observed within 3 months prior to onset of transient (≤3 months; 37.5%) or persistent OH (>3 months; 62.5%). AC cell and LF values decreased within 3 months after onset of transient OH, while LF levels remained elevated ≥12 months in persistent OH. Optic disc edema and epiretinal membrane formation was found more frequently after OH onset. CONCLUSIONS: OH was observed in 15.6% of JIAU patients. Longer total uveitis duration, bilateral uveitis, low visual acuity, high AC flare and LF grades, and presence of posterior synechiae at baseline were risk factors for subsequent OH. Burden of OH might be improved with immunosuppression.

The pro-inflammatory role of high-mobility group box 1 protein (HMGB-1) in photoreceptors and retinal explants exposed to elevated pressure.

To determine the role of high-mobility group box 1 protein (HMGB-1) in cellular and tissue models of elevated pressure-induced neurodegeneration, regeneration, and inflammation. Mouse retinal photoreceptor-derived cells (661W) and retinal explants were incubated either under elevated pressure or in the presence of recombinant HMGB-1 (rHMGB-1) to investigate the mechanisms of response of photoreceptors. Immunohistochemistry, western blotting, and the quantitative real-time PCR were used to examine the expression levels of immunological factors (eg, HMGB-1, receptor for advanced glycation end products (RAGE)), Toll-like receptors 2 and 4 (TLR-2, TLR-4), apoptosis-related factors (eg, B-cell lymphoma 2 (Bcl-2), Bcl-2-associated death promoter (Bad)) as well as cytokine expression (eg, tumor necrosis factor alpha (TNF-α), interleukin (IL)-4, IL-6, and vascular endothelial growth factor (VEGF)). The data revealed increased the expression of HMGB-1 and its receptors RAGE, TLR-2, and TLR-4, and TNF-α as well as pro-apoptotic factors (eg, Bad) as well as apoptosis in 661W cells exposed to elevated pressure. Co-cultivation of 661W cells with rHMGB-1 increased the expression levels of pro-apoptotic Bad and cleaved Caspase-3 resulting in apoptosis. Cytokine array studies revealed an increased release of TNF-α, IL-4, IL-6, and VEGF after incubation of 661W cells with rHMGB-1. Upregulation of HMGB-1, TLR-2, and RAGE as well as anti-apoptotic Bcl-2 expression levels was found in the retinal explants exposed to rHMGB-1 or elevated pressure. The results suggest that HMGB-1 promotes an inflammatory response and mediates apoptosis in the pathology of photoreceptors and retinal homeostasis. HMGB-1 may have a key role in ongoing damage of retinal cells under conditions of elevated intraocular pressure.

Accelerated (18 mW/cm²) Corneal Collagen Cross-Linking for Progressive Keratoconus.

PURPOSE: The aim of this study was to determine the efficacy of accelerated riboflavin-ultraviolet A-induced corneal collagen cross-linking (CXL) (irradiance of 18 mW/cm² for 5 minutes). METHODS: In this study, we retrospectively reviewed the charts and anterior segment data of patients after accelerated CXL. Visual, topographic, pachymetry, and densitometry data were extracted and analyzed before surgery and at follow-up (minimum 12 months) after treatment. RESULTS: A total of 28 eyes of 20 patients (mean age, 28.1 ± 8.1 years) were included in this study. The mean follow-up time was 21.7 ± 7.2 months (range, 12-34 months). No statistically significant changes were found in the mean corrected distance visual acuity, corneal astigmatism, Kmean, Kflat, Ksteep, corneal pachymetry (at the apex and at the thinnest point), and corneal densitometry at follow-up. A significant reduction of Kmax, index of surface variance, index of vertical asymmetry, and Km of the posterior corneal surface (Km(B)) was observed (Kmax: P = 0.018; index of surface variance: P = 0.016; index of vertical asymmetry: P = 0.038; Km(B): P = 0.008). No complications were reported during the postoperative follow-up period in this study. CONCLUSIONS: Based on a mean follow-up time of 21.7 months, accelerated CXL (18 mW/cm; 5 minutes) is effective in stopping the progression of keratoconus without raising any safety concerns. Improvement in Kmax and stabilization of corrected distance visual acuity were noted after treatment. However, prospective studies with longer follow-up using different accelerated CXL settings are needed to validate these findings.

ßB2-Crystallin Promotes Axonal Regeneration in the Injured Optic Nerve in Adult Rats.

The purpose of the study was to further scrutinize the potential of ßB2-crystallin in supporting regeneration of injured retinal ganglion cell axons both in vitro and in vivo. Retinal explants obtained from animals after treatment either with lens injury (LI) alone or with combined LI 5 days or 3 days before or simultaneously with an optic nerve crush (ONC) were cultured for 96 h under regenerative conditions, and the regenerating axons were quantified and compared with untreated controls. These measurements were then repeated with LI replaced by intravitreal injections of γ-crystallin and ß-crystallin at 5 days before ONC. Finally, ßB2-crystallin-overexpressing transfected neural progenitor cells (ßB2-crystallin-NPCs) in the eye were studied after crushing the optic nerve in vivo. Regeneration was monitored with the aid of immunoblotting of the retina and optic nerve both distal and proximal to the lesion site, and this was compared with controls that received injections of phosphate buffer only. LI performed 5 days or 3 days before ONC significantly promoted axonal outgrowth in vitro (p < 0.001), while LI performed alone before explantation did not. Intravitreal injections of ß-crystallin and γ-crystallin mimicked the effects of LI and significantly increased axonal regeneration in culture at the same time intervals (p < 0.001). Western blot analysis revealed that crystallins were present in the proximal optic nerve stump at the lesion site in ONC, but were neither expressed in the undamaged distal optic nerve nor in uninjured tissue. ßB2-crystallin-NPCs supported the regeneration of cut optic nerve axons within the distal optic nerve stump in vivo. The reported data suggest that ßB2-crystallin-producing "cell factories" could be used to provide novel therapeutic drugs for central nervous system injuries.

Macula-less rat and macula-bearing monkey retinas exhibit common lifelong proteomic changes.

The visual consequences of age-related alterations in the neural retina have been well documented, but little is known about their molecular bases. We performed a comparative proteomic analysis of the retinas in marmosets and rats to identify proteins for which the expression profiles are altered with maturation and aging. Protein profiles were compared in the newborn, juvenile, middle-age, and aged retinas using 2-dimensional gel electrophoresis. Matrix-assisted desorption ionization-time-of-flight mass spectrometry revealed common proteins in rats and marmosets that exhibited changes in concentration throughout life. Western blot, quantitative reverse-transcriptase polymerase chain reaction, and immunohistochemistry analyses of selected proteins and their mRNA were used to determine whether the changes identified by proteomics were verifiable at the cellular and molecular levels. We found 4 proteins common to both species (Parkinson disease [autosomal recessive, early onset] 7/DJ-1, stathmin, peroxiredoxin, and ß-synuclein) whose concentrations were regulated with age. These findings were confirmed by Western blot, immunohistochemistry, and quantitative reverse-transcriptase polymerase chain reaction analyses. The proteins were localized in certain layers and subsets of cells within the retinas of both species. The expression of these proteins in the adult human retina was confirmed with immunohistochemistry. The present study is the first to provide evidence that the retina is physiologically characterized by specific lifelong changes in its proteome. These changes are independent of whether the retina bears a macula, occur in key functional pathways during the processing of visual signals, and might be involved in the development of age-related pathologic entities.

Effects of crystallin-ß-b2 on stressed RPE in vitro and in vivo.

BACKGROUND: Crystallins are thought to play a cytoprotective role in conditions of cellular stress. The aim of this study was to determine the effects of crystallin-ß-b2 (cryß-b2) and crystallin-ß-b3 (cryß-b3) on ARPE-19 cells in vitro and on the retinal pigment epithelium (RPE) in vivo. METHODS: The influence of cryß-b2 and cryß-b3 on the viability, proliferation and dying of ARPE-19 was measured by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium assay, bromo-2-deoxyuridine assay and life/death assay. The expressions of cryß-b2, cryß-b3, glial-derived neurotrophic factor (GDNF), and galectin-3 (Gal-3) in ARPE-19 cells were evaluated using immunohistochemistry (IHC), Western blotting (WB) and real-time-quantitative-PCR (qRT-PCR). To evaluate the response of cryß-b2 and cryß-b3 to stressed ARPE-19 cells, the cells were exposed to UV-light. In a rat model, cryß-b2-expressing neural progenitor cells (cryß-b2-NPCs) were injected intravitreally after retinal stress induced by optic nerve axotomy to examine whether they influence the RPE. Protein expression was examined 2 and 4 weeks postsurgery using IHC and WB. RESULTS: Detectable alterations of GDNF, and Gal-3 were found in ARPE-19 cells upon exposure to UV light. Adding the crystallins to the medium promoted proliferation and increased viability of ARPE-19 cells in vitro. The obtained data support the view that these crystallins possess epithelioprotective properties. Likewise, in vivo, intravitreally injected cryß-b2 and transplanted cryß-b2-NPCs protected RPE from indirectly induced stress. CONCLUSIONS: The data suggest that the RPE response to retinal ganglion cell denegeration is mediated via crystallins, which may thus be used therapeutically.

Crystallin-ß-b2-overexpressing NPCs support the survival of injured retinal ganglion cells and photoreceptors in rats.

PURPOSE: Crystallin ß-b2 (crybb2) is known to support the regeneration of retinal ganglion cell (RGC) axons in culture. We investigated whether neuronal progenitor cells (NPCs) overexpressing crybb2 (crybb2-NPC) affect secondary retinal degeneration due to optic nerve crush in vivo. METHODS: NPCS were produced by dissociation and propagation of rat embryonic neural tube and eye primordial cells at embryonic days 13.5 and 15. Retinal degeneration was induced by injured optic nerve crush (BY suture, 20 seconds). Several groups were built: crybb2-NPC were injected into the vitreous body, while the Controls were comprised of recombinant crybb2-injected and PBS-injected groups. The eyes, in particular the retina, were analyzed by immunohistochemistry and Western blotting for different antigens at 2 and 4 weeks after surgery. RESULTS: At 2 and 4 weeks post surgery, crybb2-NPC resided within the vitreoretinal compartment, and were persistently nestin-positive throughout the experimental period. The cells stained positive for various neurotrophins and acted as "living" cell factories to support the survival of injured RGCs. The crybb2-NPC migrated throughout the eye structures and sometimes became integrated within the tissue. Most of the ocular cells responded to the appearance of crybb2-NPC with marked changes of certain proteins, including Iba-1 (microglia), vimentin (glial cells), and rhodopsin (photoreceptors). Photoreceptors also displayed a better survival after crybb2-NPC injection compared to control groups. CONCLUSIONS: Crybb2-NPC exert beneficial effects on the vitreoretinal compartment, which suggests that modified crybb2-NPC could be used in a novel strategy for the treatment of degenerative vitreoretinal diseases. However, future studies must determine the safety of in vivo administration of crybb2-NPC.

Use of intravitreal triamcinolone and bevacizumab in Coats' disease with central macular edema.

BACKGROUND: Intravitreal application of triamcinolone and bevacizumab in Coats' disease with macular edema to improve visual outcome. METHODS: Testing of best-corrected visual acuity (BCVA), ophthalmoscopy, optical coherence tomography, fluorescein angiography, 30° perimetry, and full-field electroretinography were performed at initial and follow-up visits. Medical treatment consisted of intravitreal injection of 1.25 mg bevazicumab and 1.25 mg triamcinolone, followed by intravitreal injections of 1.25 mg bevazicumab at weeks 4 and 10. Follow-up was 87 weeks. RESULTS: Perimetric results, including a temporal absolute scotoma and reduced electroretinographic amplitudes (photopic and scotopic conditions), did not significantly change during the follow-up, but foveal retinal thickness decreased from 505 µm to 212 µm, and BCVA increased from 0.3 at baseline to 1.25 and remained stable during subsequent follow-up. CONCLUSIONS: Combined intravitreal treatment with bevacizumab and triamcinolone resulted in significant decrease of central retinal thickness and improved visual acuity in this case report. Severe local or systemic side-effects were not observed.