Impact of symptomatic vitreous degeneration on photopic and mesopic contrast thresholds.

CLINICAL RELEVANCE: Contrast thresholds under photopic and mesopic luminance conditions are compromised in subjects with vitreous degeneration. A plausible explanation is needed for the visual discomfort expressed by patients suffering from symptomatic vitreous degeneration. BACKGROUND: The current study investigates the effect of symptomatic vitreous degeneration on photopic and mesopic contrast at high spatial frequencies. METHODS: An age-matched sample of 115 subjects, comprising 30 subjects with symptomatic vitreous floaters (cases) and 85 healthy subjects (controls), was included in this study. Visual acuity and flicker thresholds were measured for all participants. Photopic and mesopic functional contrast thresholds at 10 cycles per degree were measured for all participants to assess the effect of floaters on contrast. Further, to determine the effect of posterior vitreous detachment on contrast, the sample was divided into three groups: cases with posterior vitreous detachment (n = 12); cases without posterior vitreous detachment (n = 18); and controls (n = 85), and their contrast thresholds were compared. RESULTS: Photopic and mesopic contrast thresholds were lower by 37.4% and 27.5%, respectively, when the cases were compared with the controls (p = 0.028 and p < 0.001 for photopic and mesopic contrast thresholds, respectively). Photopic contrast was lower by 64.0% in cases with posterior vitreous detachment compared with controls (p = 0.001). Compared with controls, mesopic contrast was lower in cases with posterior vitreous detachment and in cases without posterior vitreous detachment by 30.3% and 25.6%, respectively (p = 0.014 and p = 0.017 for cases with and without posterior vitreous detachment, respectively). CONCLUSION: : Subjects with vitreous degeneration have diminished photopic and mesopic contrast thresholds compared with controls. This finding highlights the negative impact of vitreous degeneration on the quality of vision.

Dietary Intervention With a Targeted Micronutrient Formulation Reduces the Visual Discomfort Associated With Vitreous Degeneration.

Purpose: To investigate the impact of supplementation with a targeted micronutrient formulation on the visual discomfort associated with vitreous degeneration. Methods: In this clinical trial, 61 patients with symptomatic vitreous floaters were randomized to consume daily, the active supplement consisting of 125 mg L-lysine, 40 mg vitamin C, 26.3 mg Vitis vinifera extract, 5 mg zinc, and 100 mg Citrus aurantium or placebo for 6 months. Change in visual discomfort from floaters, assessed with the Floater Disturbance Questionnaire, was the primary outcome measure. Secondary outcome measures included best-corrected visual acuity, letter contrast sensitivity, photopic functional contrast sensitivity with positive and negative contrast polarity, and quantitative vitreous opacity areas. Results: After supplementation, the active group reported a significant decrease in their visual discomfort from floaters (P < 0.001), whereas the placebo group had no significant change in their visual discomfort (P = 0.416). At 6 months, there was a significant decrease in vitreous opacity areas in the active group (P < 0.001) and an insignificant increase in vitreous opacity areas in the placebo group (P = 0.081). Also, there was a significant improvement in photopic functional contrast sensitivity with positive contrast polarity in the active group after supplementation (P = 0.047). Conclusions: The findings of this study indicate improvements in vision-related quality of life and visual function of patients suffering from vitreous floaters after supplementation with a formulation of antioxidative and antiglycation micronutrients. Notably, these improvements were confirmed by the decrease in vitreous opacity areas in the active group. Translational Relevance: This targeted dietary intervention should be considered to support patients with symptomatic vitreous degeneration.

MIGS: therapeutic success of combined Xen Gel Stent implantation with cataract surgery.

PURPOSE: Glaucoma, a common disease in the elderly population, is frequently coexistent with cataract. While the combination of filtration surgery and cataract surgery is a challenging topic with limited success, minimal invasive glaucoma surgery (MIGS), such as Xen Gel Stents, seems to provide promising results. The aim of this study was to investigate the complete and qualified therapeutic success of Xen Gel Stent implantation with (XenPhaco) and without cataract surgery. METHODS: One hundred and eleven open-angle glaucoma eyes underwent implantation of Xen45 Gel Stent (AqueSys, Inc.) with or without cataract operation. Complete therapeutic success was defined as target intraocular pressure (IOP) < 18 mmHg at any time point within 6 months of follow-up without local antiglaucomatous therapy or further surgical interventions. Qualified success was defined as target IOP <18 mmHg with additional 1-2 local antiglaucomatous eye drops. Failure included all cases with the necessity of at least three local antiglaucomatous eye drops or additional glaucoma surgery. RESULTS: Combined implantation of Xen Gel Stent with cataract surgery was performed in 30 eyes and stand-alone Xen Gel Stent implantation was performed in 81 eyes. A complete therapeutic success was achieved in 46.9% of single Xen Gel Stent implantation, whereas 53.3% was reached with combined XenPhaco. Qualified success was seen in 2.5% in the eyes of the single Xen Gel Stent implantation group and in 3.3% of the combined surgery group. Therapeutic failure rate was 49.4% in the stand-alone group vs 46.7% in the combined group. Data were not significantly different for group and subgroup analyses. CONCLUSIONS: Complete and qualified therapeutic success is similar for the combination of Xen Gel Stent implantation with and without cataract surgery in open-angle glaucoma patients. MIGS using Xen Gel Stent can be recommended in situations if glaucoma surgery is indicated besides coexisting cataract.

Assessing the adherence behavior of glaucoma patients to topical eye drops.

PURPOSE: The goal of this study was to determine the adherence of glaucoma patients to their topical glaucoma medication. Furthermore, the relationships between the adherence behavior and the patients' demographic data, clinical characteristics, and their knowledge about glaucoma were evaluated. METHODS: This was a prospective study of 123 patients with primary open-angle glaucoma who were given two standardized questionnaires. The first questionnaire at time point T1 comprised a knowledge assessment and the self-reported adherence measures Adherence to Refills and Medication Scale 2 (ARMS2), visual analogue scale for adherence (VAS-AD), and missed doses in the past 14 days. Two months later at time point T2, a second questionnaire reevaluated the adherence measures ARMS2, VAS-AD, and missed doses in the past 14 days. RESULTS: There was a good correlation among all the three adherence measures at T1 and T2. The mean values of ARMS2 were in the lower range, with 3.38 at T1 and 2.8 at T2. The VAS-AD detected that 18.5% of patients always took their eye drops correctly, and 77.9% of patients reported not to have missed a single dose in the past 14 days. There was no significant correlation between the patients' demographic data or knowledge about glaucoma and the adherence measures ARMS2 or VAS-AD. Among the clinical characteristics, only single-eye blindness showed a significant correlation with VAS-AD. CONCLUSION: In this study, no general relationships were found between medication adherence and the patients' demographic data, clinical characteristics, or knowledge about glaucoma. It may be assumed that more individualized strategies are required to optimize adherence behavior.

Macular pigment optical density measured by heterochromatic modulation photometry.

PURPOSE: To psychophysically determine macular pigment optical density (MPOD) employing the heterochromatic modulation photometry (HMP) paradigm by estimating 460 nm absorption at central and peripheral retinal locations. METHODS: For the HMP measurements, two lights (B: 460 nm and R: 660 nm) were presented in a test field and were modulated in counterphase at medium or high frequencies. The contrasts of the two lights were varied in tandem to determine flicker detection thresholds. Detection thresholds were measured for different R:B modulation ratios. The modulation ratio with minimal sensitivity (maximal threshold) is the point of equiluminance. Measurements were performed in 25 normal subjects (11 male, 14 female; age: 30 ± 11 years, mean ± sd) using an eight channel LED stimulator with Maxwellian view optics. The results were compared with those from two published techniques - one based on heterochromatic flicker photometry (Macular Densitometer) and the other on fundus reflectometry (MPR). RESULTS: We were able to estimate MPOD with HMP using a modified theoretical model that was fitted to the HMP data. The resultant MPODHMP values correlated significantly with the MPODMPR values and with the MPODHFP values obtained at 0.25° and 0.5° retinal eccentricity. CONCLUSIONS: HMP is a flicker-based method with measurements taken at a constant mean chromaticity and luminance. The data can be well fit by a model that allows all data points to contribute to the photometric equality estimate. Therefore, we think that HMP may be a useful method for MPOD measurements, in basic and clinical vision experiments.

Perioperative and postoperative risk factors for corneal graft failure.

PURPOSE: In this study, we assessed the outcome of penetrating keratoplasties using organ-cultured corneal tissues at the University Eye Hospital, Ludwig-Maximilians-University, Munich, Germany. The goal was to identify perioperative and postoperative risk factors that may affect graft survival. PATIENTS AND METHODS: The medical records of 377 patients who underwent a penetrating keratoplasty between 2001 and 2011 were reviewed. Organ-cultured corneal tissue was obtained from the eye bank of Ludwig-Maximilians-University. Perioperative and postoperative risk factors for graft failure were evaluated by univariate and multivariate analyses. RESULTS: The 5-year overall survival rate of penetrating keratoplasties was 68%. Graft failure occurred in 26% of patients. High-risk keratoplasties, such as repeat penetrating keratoplasties and emergency penetrating keratoplasties, as well as postoperative conditions, such as glaucoma, retinal surgery, suture problems, persistent epithelial defect, infectious keratitis, and graft rejection, were significantly associated with graft failure in the multivariate analyses. CONCLUSION: This study showed a similar graft-survival rate as demonstrated in previous studies. In addition, a number of perioperative and postoperative risk factors were identified in this specific patient population.

Donor-related risk factors and preoperative recipient-related risk factors for graft failure.

PURPOSE: The aim of this study was to evaluate the outcome of penetrating keratoplasties, at the University Eye Hospital, Ludwig-Maximilians-University, Munich, Germany, using organ-cultured donor corneas and to identify preoperative risk factors, which may influence the event of graft failure. METHODS: In this study, 377 medical records of patients, who underwent penetrating keratoplasty between 2001 and 2011, were reviewed. Organ-cultured donor corneas were obtained from the eye bank, Ludwig-Maximilians-University, Munich, Germany. Donor-related and preoperative recipient-related risk factors for graft failure were analyzed by univariate and multivariate analyses. RESULTS: Graft failure occurred in 26% of patients. The following preoperative factors were significantly associated with graft failure by multivariate analyses: high donor age, low donor endothelial cell density, high patient age, indications of infectious keratitis, acute perforation of noninfectious keratitis, prior graft failure, chemical burn, trauma, glaucoma-associated corneal decompensation, high-risk graft indications, corneal edema, anterior chamber lens, diabetes mellitus, atopy, and autoimmune diseases. CONCLUSIONS: This study demonstrated a success rate of 74%, which is consistent with previous studies. Various preoperative recipient-related factors seem to influence the outcome of penetrating keratoplasties, whereas few donor-related factors have a significant association with graft failure.

Intensity of side effects of topical glaucoma medication and its influence on adherence behavior in patients with glaucoma.

BACKGROUND: The aim of this study was to investigate the intensity of side effects that patients attribute to their topical glaucoma medication and their relationship to adherence behavior. METHODS: This was a questionnaire-based study of 123 glaucoma patients at a university eye clinic in Erlangen, Germany. An initial questionnaire asked about patient demographic data, the treatment plan, and intensity of side effects, and included Adherence to Refills and Medication Scale 2 (ARMS2) and visual analog scale (VAS-AD) scores. In a follow-up questionnaire, the treatment plan, intensity of side effects, ARMS2, and VAS-AD were reanalyzed. RESULTS: Most patients reported having few side effects, although only 20% said that they had no symptoms suggestive of side effects at all. The patients showed good adherence behavior on both the ARMS2 and VAS-AD scores, which were stable over time. The intensity of side effects experienced in the previous 7 days did not correlate with adherence scores and had no predictive value for adherence. CONCLUSION: This study could not detect any significant influence of the subjectively experienced intensity of side effects on patients' adherence behavior. However, we believe that a simple and clear treatment plan with few side effects is still preferred by most patients.

Factors affecting the use of antioxidant supplements in patients with late AMD.

BACKGROUND: The purpose of this study was to assess the use of oral antioxidant supplements in patients with late age-related macular degeneration (AMD) and to identify influencing factors that may affect the use of such supplements. METHODS: The study included 47 patients with late AMD. Using a questionnaire, the patients were asked for their demographic, ophthalmologic, and systemic data, their source of recommendation of antioxidant use for AMD, and/or their reasons for nonuse. The demographic, ophthalmologic, and systemic information was correlated with use or nonuse of oral antioxidant supplements for AMD. RESULTS: Sixty-eight percent (32/47) of patients took antioxidant supplements for AMD and 32% (15/47) of patients did not. There were no statistically significant differences in demographic, ophthalmologic, and systemic parameters between patients with late AMD who used supplements and those who did not. Two thirds of patients with late AMD (66%, 31/47) reported being recommended oral antioxidant supplements for AMD by their ophthalmologist. Patients who did not use antioxidant supplements either did not obtain any recommendation or did not believe in their benefits. CONCLUSION: This study shows that most patients with late AMD use antioxidant supplements despite the recommendation to do so being missing in the Age-Related Eye Disease Study. Our study emphasizes the importance of seeking further therapeutic options for patients with late AMD.

Evaluation of intraocular pressure elevation after multiple injections of intravitreal ranibizumab.

BACKGROUND: We wanted to determine whether multiple injections of intravitreal ranibizumab was associated with an elevated intraocular pressure (IOP) in patients treated for neovascular age-related macular degeneration (AMD). METHODS: This retrospective study examined 53 patients with neovascular AMD treated with multiple injections of intravitreal ranibizumab. The main outcome measure was the difference in IOP between the frequently-treated study eyes (≥15 injections) and the unfrequently-treated fellow control eyes (≤ five injections). Patients were divided into three study groups: group I (35 patients with 15 to 19 injections); group II (15 patients with 20 to 29 injections); and group III (three patients with ≥30 injections). The IOP was measured by Goldmann applanation tonometry 4 weeks after the last injection of intravitreal ranibizumab. For statistical analysis, the IOP was then correlated with the number of ranibizumab injections. RESULTS: Among the frequently-treated study eyes, the mean IOP was 13.68±2.91 mmHg (range, 8 to 20 mmHg). The unfrequently-treated fellow control eyes had a mean IOP of 13.45±3.09 mmHg (range, 9 to 25 mmHg). There was no significant correlation of the IOP difference between the study and control eyes with the number of ranibizumab injections (correlation coefficient 0.77; P=0.583). For each of groups I, II, and III, the difference in mean IOP between the study and control eyes was nonsignificant (P>0.05). There was also no significant association of the IOP difference between the study and control eyes with the number of ranibizumab injections for each group (P=0.391). CONCLUSION: Our study did not find an increased IOP in frequently-ranibizumab-treated eyes when compared to unfrequently-treated fellow control eyes. Further studies with a greater sample size are needed to evaluate whether an increased number of ranibizumab injections is associated with IOP changes.

Factors influencing self-reported use of antioxidant supplements in patients with age-related macular degeneration.

AIM: The goals of the present study were to evaluate the current use and accuracy of dose-taking prescription among patients with age-related macular degeneration (AMD) and to detect potential factors influencing the use or non-use of oral antioxidant supplements. MATERIALS AND METHODS: This is a cross-sectional questionnaire-based study of 65 patients with AMD of Age-Related Eye Disease Study (AREDS) category 3 (intermediate AMD) or category 4 (unilateral advanced AMD). Self-report data were obtained from a structural clinical interview in clinic. The patients were asked questions regarding their demographic, ophthalmologic and systemic data, their source of recommendation for antioxidant supplement use and/or their reasons for non-use. Afterwards, this information was correlated with the use or non-use of antioxidant supplements. Statistical analyses were conducted using a series of Mann-Whitney U-tests and Fisher's exact tests. RESULTS: There were 55.4% (36 of 65) of the patients reporting antioxidant supplement use for AMD and 44.6% (29 of 65) with no supplement use. However, only 56.7% (17 of 30) took the recommended dose on label. There were significantly more female patients taking supplements than male patients (p = 0.010). A statistically significant correlation was also found between supplement use and the number of visits to an ophthalmologist per year (p = 0.037). The main reason for antioxidant supplement non-use was the missing awareness of the availability of antioxidant supplements. CONCLUSIONS: Despite the recommendation of oral antioxidant supplements in the ARED Study for patients with AMD of category 3 or 4, only about half of these patients took the supplements in this study. Identifying the factors, which influenced the decision against supplement use, may help to better support patients in the prevention of severe vision loss caused by AMD.

Constitutive expression of HCA(2) in human retina and primary human retinal pigment epithelial cells.

PURPOSE/AIM: HCA2, a receptor of ß-hydroxybutyrate and niacin, has recently been described in mouse retina and immortalized human retinal pigment epithelial (RPE) cell lines. As HCA2 might be a pharmacologic target, e.g. in diabetic retinopathy, we studied its expression in human retina and primary human RPE cells. MATERIALS AND METHODS: Paraffin sections of human retina and primary human RPE cells were obtained from human donor eyes. Expression of HCA2 in human retina was investigated by immunohistochemistry of paraffin sections and by RT-PCR. HCA2 expression in primary human RPE cells was examined by immunocytochemistry and by Western-blot analysis. RESULTS: Positive immunohistochemical staining for HCA2 was found in paraffin sections of human retina, and positive immunocytochemical staining for HCA2 in primary human RPE cells. RT-PCR analysis detected mRNA expression of HCA2 in human retina. The expression of HCA2 protein was found in primary human RPE cells. CONCLUSIONS: Based on these results, HCA2 appears to be constitutively expressed in human retina and in primary human RPE cells. Although its functional role is still unknown, HCA2 may be potentially involved in the pathogenesis of various retinopathies and may offer a new therapeutic target.

Vitamin E reduces TGF-beta2-induced changes in human trabecular meshwork cells.

AIM: To determine the effects of vitamin E on transforming growth factor-beta2 (TGF-ß2)-induced cellular changes in cultured human trabecular meshwork (TM) cells. MATERIALS AND METHODS: Human TM cells were pre-treated with different concentrations of vitamin E. Afterwards, cells were exposed to 1.0 ng/ml TGF-ß2 for 24 h. Expressions of the heat shock protein αB-crystallin, the extracellular matrix (ECM) component fibronectin and the ECM-degrading enzyme matrix metalloproteinase-2 (MMP-2) were examined by real-time polymerase chain reaction (PCR) analyses. The cytoskeleton was investigated by phalloidin staining. RESULTS: TGF-ß2 increased the expressions of αB-crystallin and fibronectin and reduced the levels of MMP-2. TGF-ß2 induced the formation of actin stress fibers and cross-linked actin networks. Pre-treatment with different concentrations of vitamin E reversed the TGF-ß2-induced cellular changes in cultured human TM cells. CONCLUSIONS: TGF-ß2-mediated changes in human TM cells could be reduced by pre-treatment with vitamin E. Therefore, it may be speculated that increasing the antioxidative capacity may help to lower the incidence of characteristic glaucomatous changes in the TM.

Antioxidants reduce TGF-beta2-induced gene expressions in human optic nerve head astrocytes.

PURPOSE: The goal of the present study was to investigate whether the antioxidants vitamin E, vitamin C and vitamin B1 can reduce the transforming growth factor-beta2 (TGF-ß2)-induced gene expressions in cultured human optic nerve head (ONH) astrocytes. METHODS: Cultured human ONH astrocytes were pretreated with different concentrations of vitamin E, vitamin C and vitamin B1 and then exposed to 1.0 ng/ml TGF-ß2 for 24 hr. Expression of the heat shock proteins Hsp27 and αB-crystallin, the extracellular matrix (ECM) component fibronectin and the ECM-modulating protein connective tissue growth factor (CTGF) was detected by immunohistochemistry or real-time PCR analysis. RESULTS: TGF-ß2 increased the expression of Hsp27, αB-crystallin, fibronectin and CTGF in human ONH astrocytes. Pretreatment with different concentrations of vitamin E, vitamin C and vitamin B1 reduced the TGF-ß2-stimulated gene expressions. CONCLUSION: In cultured human ONH astrocytes, the TGF-ß2-stimulated gene expressions could be reduced by pretreatment with vitamin E, vitamin C and vitamin B1. Therefore, the use of antioxidants in glaucomatous optic neuropathy might be a promising approach to prevent TGF-ß2-induced cellular changes in ONH astrocytes.

Human anterior lens capsule serving as a substrate for human trabecular meshwork cells cultivation.

To investigate if human anterior lens capsule is a suitable substrate for the culture of primary human trabecular meshwork (HTM) cells. Trabecular meshwork cells derived from four human donors were seeded on anterior lens capsules that were prepared from the lenses of donor eyes. Cell morphology and viability were examined at 1, 3, 5 and 7 days. Cell viability was measured based on a two-colour fluorescence assay (membrane-impermeable propidium iodide and membrane permeable Hoechst 33342). Immunocytochemistry studied Zonula occludens-1 (ZO-1), vimentin, tissue transglutaminase (tTgase) and Na(+)/K(+)-adenosine triphosphatase (Na(+)/K(+)-ATPase). Morphology of the cultivated cells followed a typical model while their viability was > 95% in all cases. ZO-1 was found at the cell boundaries of the HTM-AC complex. Vimentin was located at the lateral membranes of the HTM cells. Na(+)/K(+)-ATPase was found at the basolateral membrane of the HTM cells. tTgase was also identified. Anterior lens capsule can be considered as a suitable alternative substrate for cultivation of HTM cells and assist the expansion of existing knowledge about glaucoma pathophysiology and therapy.

Biological effects of cigarette smoke in cultured human retinal pigment epithelial cells.

The goal of the present study was to determine whether treatment with cigarette smoke extract (CSE) induces cell loss, cellular senescence, and extracellular matrix (ECM) synthesis in primary human retinal pigment epithelial (RPE) cells. Primary cultured human RPE cells were exposed to 2, 4, 8, and 12% of CSE concentration for 24 hours. Cell loss was detected by cell viability assay. Lipid peroxidation was assessed by loss of cis-parinaric acid (PNA) fluorescence. Senescence-associated ß-galactosidase (SA-ß-Gal) activity was detected by histochemical staining. Expression of apolipoprotein J (Apo J), connective tissue growth factor (CTGF), fibronectin, and laminin were examined by real-time PCR, western blot, or ELISA experiments. The results showed that exposure of cells to 12% of CSE concentration induced cell death, while treatment of cells with 2, 4, and 8% CSE increased lipid peroxidation. Exposure to 8% of CSE markedly increased the number of SA-ß-Gal positive cells to up to 82%, and the mRNA expression of Apo J, CTGF, and fibronectin by approximately 3-4 fold. Treatment with 8% of CSE also increased the protein expression of Apo J and CTGF and the secretion of fibronectin and laminin. Thus, treatment with CSE can induce cell loss, senescent changes, and ECM synthesis in primary human RPE cells. It may be speculated that cigarette smoke could be involved in cellular events in RPE cells as seen in age-related macular degeneration.

TGF-ß(2)- and H(2)O(2)-induced biological changes in optic nerve head astrocytes are reduced by the antioxidant alpha-lipoic acid.

BACKGROUND/AIMS: The goal of the present study was to determine whether transforming growth factor-ß(2) (TGF-ß(2))- and oxidative stress-induced cellular changes in cultured human optic nerve head (ONH) astrocytes could be reduced by pretreatment with the antioxidant α-lipoic acid (LA). METHODS: Cultured ONH astrocytes were treated with 1.0 ng/ml TGF-ß(2) for 24 h or 200 µM hydrogen peroxide (H(2)O(2)) for 1 h. Lipid peroxidation was measured by a decrease in cis-parinaric acid fluorescence. Additionally, cells were pretreated with different concentrations of LA before TGF-ß(2) or H(2)O(2) exposure. Expressions of the heat shock protein (Hsp) αB-crystallin and Hsp27, the extracellular matrix (ECM) component fibronectin and the ECM-modulating protein connective tissue growth factor (CTGF) were examined with immunohistochemistry and real-time PCR analysis. RESULTS: Both TGF-ß(2) and H(2)O(2) increased lipid peroxidation. Treatment of astrocytes with TGF-ß(2) and H(2)O(2) upregulated the expression of αB-crystallin, Hsp27, fibronectin and CTGF. Pretreatment with different concentrations of LA reduced the TGF-ß(2)- and H(2)O(2)-stimulated gene expressions. CONCLUSION: We showed that TGF-ß(2)- and H(2)O(2)-stimulated gene expressions could be prevented by pretreatment with the antioxidant LA in cultured human ONH astrocytes. Therefore, it is tempting to speculate that the use of antioxidants could have protective effects in glaucomatous optic neuropathy.

Common genetic determinants of intraocular pressure and primary open-angle glaucoma.

Intraocular pressure (IOP) is a highly heritable risk factor for primary open-angle glaucoma and is the only target for current glaucoma therapy. The genetic factors which determine IOP are largely unknown. We performed a genome-wide association study for IOP in 11,972 participants from 4 independent population-based studies in The Netherlands. We replicated our findings in 7,482 participants from 4 additional cohorts from the UK, Australia, Canada, and the Wellcome Trust Case-Control Consortium 2/Blue Mountains Eye Study. IOP was significantly associated with rs11656696, located in GAS7 at 17p13.1 (p=1.4×10(-8)), and with rs7555523, located in TMCO1 at 1q24.1 (p=1.6×10(-8)). In a meta-analysis of 4 case-control studies (total N = 1,432 glaucoma cases), both variants also showed evidence for association with glaucoma (p=2.4×10(-2) for rs11656696 and p=9.1×10(-4) for rs7555523). GAS7 and TMCO1 are highly expressed in the ciliary body and trabecular meshwork as well as in the lamina cribrosa, optic nerve, and retina. Both genes functionally interact with known glaucoma disease genes. These data suggest that we have identified two clinically relevant genes involved in IOP regulation.

Preventive effects of omega-3 and omega-6 Fatty acids on peroxide mediated oxidative stress responses in primary human trabecular meshwork cells.

Pathologic processes in glaucoma include increased apoptosis, accumulation of extracellular material in the trabecular meshwork and optic nerve, condensations of the cytoskeleton and precocious cellular senescence. Oxidative stress was shown to generate these alterations in primary ocular cells. Fatty acids omega-3 and -6 are alleged to constitute a prophylaxis against these deleterious effects. Here, we tested actual preventive effects omega-3 and -6 against peroxide induced stress responses in primary human trabecular meshwork cells. Changes of mitochondrial activity, proliferation, heat shock proteins, extracellular matrix components, and inflammatory markers were evaluated. Alterations of the cytoskeleton were evaluated by phalloidin labeling. Here we report a repressive effect of omega-6 on metabolic activity and proliferation, which was not detected for omega-3. Both agents were able to prevent the anti-proliferative effect of H2O2, but only omega-3 prevented metabolic repression. Expression of heat shock protein 27 was unaltered by both fatty acids, whereas heat shock protein 90 was significantly induced by both. Omega-6 increased fibronectin and connective tissue growth factor synthesis, as well as the amount of secreted fibronectin. Omega-3, instead, induced plasminogen activator inhibitor 1 synthesis. H2O2 further increased fibronectin production in omega-6 supplemented cells, which was not the case in omega-3 treated cells. H2O2 stimulation of plasminogen activator inhibitor 1 and connective tissue growth factor was repressed by both fatty acids. Both fatty acids appeared to abolish H2O2 mediated stimulation of nuclear factor κB and IL-6, but not IL-1α and IL-8. H2O2 induced formation of cross-linked actin networks and stress fibers, which was reduced by preemptive application of omega-3. Omega-6, in contrast, had no protective effect on that, and even seemed to promote condensation. Based on the observed side effects of omega-6, omega-3 appears to be the more beneficial fatty acid in respect of prophylactic intake for prevention of a glaucomatous disease.

TGF-{beta}2 induces senescence-associated changes in human trabecular meshwork cells.

PURPOSE: Recent studies have revealed an accumulation of senescent cells in the outflow pathways in primary open-angle glaucoma (POAG). Transforming growth factor (TGF)-ß2 is thought to be involved in the pathologic changes of the trabecular meshwork (TM) of POAG eyes. The goal of this study was to determine whether TGF-ß2 triggers senescence-associated changes in human TM cells in vitro. METHODS: Cultured human TM cells were exposed to 1.0 ng/mL TGF-ß2 for 12, 24, and 48 hours. Senescence-associated ß-galactosidase (SA-ß-Gal) activity was investigated by histochemical staining. Lipid peroxidation was assessed after TGF-ß2 treatment. Levels of apolipoprotein J (Apo J), SM22, and osteonectin (SPARC) mRNA were determined by real-time PCR analysis. Furthermore, the effects of antioxidants on these TGF-ß2-mediated changes were tested. Induction of senescence-related signal transduction proteins (p16, p21, and pRb) was examined by real-time PCR and Western blot analysis. RESULTS: TGF-ß2 increased SA-ß-Gal activity, lipid peroxidation, and the mRNA expressions of Apo J, SM22, and SPARC. These TGF-ß2-induced changes were attenuated by antioxidants. TGF-ß2 increased p16 mRNA and protein expression, which was paralleled by a downregulation of pRb protein. There was no effect on p21 mRNA and protein expression after exposure to TGF-ß2. CONCLUSIONS: TGF-ß2 induces senescence-associated TM changes and activates the senescence-related p16-pRb signal transduction pathway in vitro. Thus, minimizing TGF-ß2 levels may help to prevent the ageing process in the TM as seen in POAG.