Influence of Growth Differentiation Factor 15 on Intraocular Pressure in Mice.

Growth differentiation factor 15 (GDF15), a stress-sensitive cytokine, and a distant member of the transforming growth factor ß superfamily, has been shown to exhibit increased levels with aging, and in various age-related pathologies. Although GDF15 levels are elevated in the aqueous humor (AH) of glaucoma (optic nerve atrophy) patients, the possible role of this cytokine in the modulation of intraocular pressure (IOP) or AH outflow is unknown. The current study addresses this question using transgenic mice expressing human GDF15 and GDF15 null mice, and by perfusing enucleated mouse eyes with recombinant human GDF15 (rhGDF15). Treatment of primary cultures of human trabecular meshwork cells with a telomerase inhibitor, an endoplasmic reticulum stress-inducing agent, hydrogen peroxide, or an autophagy inhibitor resulted in significant elevation in GDF15 levels relative to the respective control cells. rhGDF15 stimulated modest but significant increases in the expression of genes encoding the extracellular matrix, cell adhesion proteins, and chemokine receptors (C-C chemokine receptor type 2) in human trabecular meshwork cells compared with controls, as deduced from the differential transcriptional profiles using RNA-sequencing analysis. There was a significant increase in IOP in transgenic mice expressing human GDF15, but not in GDF15 null mice, compared with the respective wild-type control mice. The AH outflow facility was decreased in enucleated wild-type mouse eyes perfused with rhGDF15. Light microcopy-based histologic examination of the conventional AH outflow pathway tissues did not reveal identifiable differences between the GDF15-targeted and control mice. Taken together, these results reveal the modest elevation of IOP in mice expressing human GDF15 possibly stemming from decreased AH outflow through the trabecular pathway.

Role of vasorin, an anti-apoptotic, anti-TGF-ß and hypoxia-induced glycoprotein in the trabecular meshwork cells and glaucoma.

Glaucoma, one of the leading causes of irreversible blindness, is commonly associated with elevated intraocular pressure due to impaired aqueous humour (AH) drainage through the trabecular meshwork. The aetiological mechanisms contributing to impaired AH outflow, however, are poorly understood. Here, we identified the secreted form of vasorin, a transmembrane glycoprotein, as a common constituent of human AH by mass spectrometry and immunoblotting analysis. ELISA assay revealed a significant but marginal decrease in vasorin levels in the AH of primary open-angle glaucoma patients compared to non-glaucoma cataract patients. Human trabecular meshwork (HTM) cells were confirmed to express vasorin, which has been shown to possess anti-apoptotic and anti-TGF-ß activities. Treatment of HTM cells with vasorin induced actin stress fibres and focal adhesions and suppressed TGF-ß2-induced SMAD2/3 activation in HTM cells. Additionally, cobalt chloride-induced hypoxia stimulated a robust elevation in vasorin expression, and vasorin suppressed TNF-α-induced cell death in HTM cells. Taken together, these findings reveal the importance of vasorin in maintenance of cell survival, inhibition of TGF-ß induced biological responses in TM cells, and the decreasing trend in vasorin levels in the AH of glaucoma patients suggests a plausible role for vasorin in the pathobiology of ocular hypertension and glaucoma.

Differentially expressed microRNAs in the aqueous humor of patients with exfoliation glaucoma or primary open-angle glaucoma.

Both exfoliation glaucoma (XFG) and primary open-angle glaucoma (POAG) have been linked to decreased conventional outflow of aqueous humor (AH). To better understand the molecular changes in the AH content under such conditions, we analyzed the miRNA profiles of AH samples from patients with POAG and XFG compared to non-glaucoma controls. Individual AH samples (n = 76) were collected from POAG and XFG patients and age-matched controls during surgical procedure. After RNA extraction, the miRNA profiles were individually determined in 12 POAG, 12 XFG and 11 control samples. We identified 205, 295 and 195 miRNAs in the POAG, XFG and control samples, respectively. Our differential expression analysis identified three miRNAs (miR-125b-5p, miR-302d-3p and miR-451a) significantly different between POAG and controls, five miRNAs (miR-122-5p, miR-3144-3p, miR-320a, miR-320e and miR-630) between XFG and controls and one miRNA (miR-302d-3p) between POAG and XFG. While none of these miRNAs have been previously linked to glaucoma, miR-122-5p may target three glaucoma-associated genes: OPTN, TMCO1 and TGF-ß1. Pathway analysis revealed that these miRNAs are involved in potential glaucoma pathways, including focal adhesion, tight junctions, and TGF-ß signaling. Comparison of the miRNA profile in AH to unrelated human serum (n = 12) exposed potential relationships between these two fluids, although they were not significantly correlated. In summary, we have successfully profiled the miRNA expression without amplification in individual human AH samples and identified several POAG or XFG-associated miRNAs. These miRNAs may play a role in pathways previously implicated in glaucoma and act as biomarkers for disease pathogenesis.

Association of Genetic Variants With Primary Open-Angle Glaucoma Among Individuals With African Ancestry.

Importance: Primary open-angle glaucoma presents with increased prevalence and a higher degree of clinical severity in populations of African ancestry compared with European or Asian ancestry. Despite this, individuals of African ancestry remain understudied in genomic research for blinding disorders. Objectives: To perform a genome-wide association study (GWAS) of African ancestry populations and evaluate potential mechanisms of pathogenesis for loci associated with primary open-angle glaucoma. Design, Settings, and Participants: A 2-stage GWAS with a discovery data set of 2320 individuals with primary open-angle glaucoma and 2121 control individuals without primary open-angle glaucoma. The validation stage included an additional 6937 affected individuals and 14 917 unaffected individuals using multicenter clinic- and population-based participant recruitment approaches. Study participants were recruited from Ghana, Nigeria, South Africa, the United States, Tanzania, Britain, Cameroon, Saudi Arabia, Brazil, the Democratic Republic of the Congo, Morocco, Peru, and Mali from 2003 to 2018. Individuals with primary open-angle glaucoma had open iridocorneal angles and displayed glaucomatous optic neuropathy with visual field defects. Elevated intraocular pressure was not included in the case definition. Control individuals had no elevated intraocular pressure and no signs of glaucoma. Exposures: Genetic variants associated with primary open-angle glaucoma. Main Outcomes and Measures: Presence of primary open-angle glaucoma. Genome-wide significance was defined as P < 5 × 10-8 in the discovery stage and in the meta-analysis of combined discovery and validation data. Results: A total of 2320 individuals with primary open-angle glaucoma (mean [interquartile range] age, 64.6 [56-74] years; 1055 [45.5%] women) and 2121 individuals without primary open-angle glaucoma (mean [interquartile range] age, 63.4 [55-71] years; 1025 [48.3%] women) were included in the discovery GWAS. The GWAS discovery meta-analysis demonstrated association of variants at amyloid-ß A4 precursor protein-binding family B member 2 (APBB2; chromosome 4, rs59892895T>C) with primary open-angle glaucoma (odds ratio [OR], 1.32 [95% CI, 1.20-1.46]; P = 2 × 10-8). The association was validated in an analysis of an additional 6937 affected individuals and 14 917 unaffected individuals (OR, 1.15 [95% CI, 1.09-1.21]; P < .001). Each copy of the rs59892895*C risk allele was associated with increased risk of primary open-angle glaucoma when all data were included in a meta-analysis (OR, 1.19 [95% CI, 1.14-1.25]; P = 4 × 10-13). The rs59892895*C risk allele was present at appreciable frequency only in African ancestry populations. In contrast, the rs59892895*C risk allele had a frequency of less than 0.1% in individuals of European or Asian ancestry. Conclusions and Relevance: In this genome-wide association study, variants at the APBB2 locus demonstrated differential association with primary open-angle glaucoma by ancestry. If validated in additional populations this finding may have implications for risk assessment and therapeutic strategies.

Genetic variants and cellular stressors associated with exfoliation syndrome modulate promoter activity of a lncRNA within the LOXL1 locus.

Exfoliation syndrome (XFS) is a common, age-related, systemic fibrillinopathy. It greatly increases risk of exfoliation glaucoma (XFG), a major worldwide cause of irreversible blindness. Coding variants in the lysyl oxidase-like 1 (LOXL1) gene are strongly associated with XFS in all studied populations, but a functional role for these variants has not been established. To identify additional candidate functional variants, we sequenced the entire LOXL1 genomic locus (∼40 kb) in 50 indigenous, black South African XFS cases and 50 matched controls. The variants with the strongest evidence of association were located in a well-defined 7-kb region bounded by the 3'-end of exon 1 and the adjacent region of intron 1 of LOXL1. We replicated this finding in US Caucasian (91 cases/1031 controls), German (771 cases/1365 controls) and Japanese (1484 cases/1188 controls) populations. The region of peak association lies upstream of LOXL1-AS1, a long non-coding RNA (lncRNA) encoded on the opposite strand of LOXL1. We show that this region contains a promoter and, importantly, that the strongly associated XFS risk alleles in the South African population are functional variants that significantly modulate the activity of this promoter. LOXL1-AS1 expression is also significantly altered in response to oxidative stress in human lens epithelial cells and in response to cyclic mechanical stress in human Schlemm's canal endothelial cells. Taken together, these findings support a functional role for the LOXL1-AS1 lncRNA in cellular stress response and suggest that dysregulation of its expression by genetic risk variants plays a key role in XFS pathogenesis.

RhoA GTPase-induced ocular hypertension in a rodent model is associated with increased fibrogenic activity in the trabecular meshwork.

Ocular hypertension arising from increased resistance to aqueous humor (AH) outflow through the trabecular meshwork is a primary risk factor for open-angle glaucoma, a leading cause of blindness. Ongoing efforts have found little about the molecular and cellular bases of increased resistance to AH outflow through the trabecular meshwork in ocular hypertension patients. To test the hypothesis that dysregulated Rho GTPase signaling and a resulting fibrotic activity within the trabecular meshwork may result in ocular hypertension, we investigated the effects of expressing a constitutively active RhoA GTPase (RhoAV14) in the AH outflow pathway in Sprague-Dawley rats by using lentiviral vector-based gene delivery. Rats expressing RhoAV14 in the iridocorneal angle exhibited a significantly elevated intraocular pressure. Elevated intraocular pressure in the RhoAV14-expressing rats was associated with fibrotic trabecular meshwork and increased levels of F-actin, phosphorylated myosin light chain, α-smooth muscle actin, collagen-1A, and total collagen in the trabecular AH outflow pathway. Most of these changes were ameliorated by topical application of Rho kinase inhibitor. Human autopsy eyes from patients with glaucoma exhibited significant increases in levels of collagen-1A and total collagen in the trabecular AH outflow pathway. Collectively, these observations indicate that increased fibrogenic activity because of dysregulated RhoA GTPase activity in the trabecular AH outflow pathway increases intraocular pressure in a Rho kinase-dependent manner.

Human aqueous humor exosomes.

Aqueous humor (AH) is a dynamic intraocular fluid that supports the vitality of tissues that regulate intraocular pressure. We recently discovered that extracellular nanovesicles called exosomes are a major constituent of AH. Exosomes function in extracellular communication and contain proteins and small RNA. Our goal was to characterize the physical properties of AH exosomes and their exosomal RNA (esRNA) content. We isolated exosomes from human AH collected during cataract surgery from five patients using serial ultracentrifugation. We measured the size and concentration of AH exosomes in solution using nanoparticle tracking analysis. We found a single population of vesicles having a mean size of 121 ± 11 nm in the unprocessed AH. Data show that centrifugation does not significantly affect the mean particle size (121 ± 11 nm versus 124 ± 21 nm), but does impact the final number of exosomes in solution (87% loss from the unprocessed AH; n = 5). We extracted esRNA from the pooled human AH samples using miRCURY RNA isolation kit from Exiqon. The quality of extracted esRNA was evaluated using Agilent Bioanalyzer 2100 and was used to generate a sequencing library for small RNA sequencing with Illumina MiSeq sequencer. More than 10 different miRNAs were identified; abundant species included miR-486-5p, miR-204, and miR-184. We found that the majority of extracellular vesicles in the AH were in the exosome size range, suggesting that miRNAs housed within exosomes may function in communication between AH inflow and outflow tissues.

Osteogenesis imperfecta and primary open angle glaucoma: genotypic analysis of a new phenotypic association.

PURPOSE: Osteogenesis imperfecta (OI) is a group of inherited disorders characterized by bone fragility. Ocular findings include blue sclera, low ocular rigidity, and thin corneal thickness. However, there are no documented cases linking OI and primary open angle glaucoma (POAG). In this report, we describe three individuals, one isolated case and two from a multiplex family, with OI type I and POAG. METHODS: Available family members with OI and POAG had a complete eye examination, including visual acuity, intraocular pressure (IOP), pachymetry, slit-lamp exam, dilated fundus exam, and visual fields. DNA from blood samples was sequenced and screened for mutations in COL1A1/2 and myocilin (MYOC). RESULTS: All subjects had OI type I. Findings of POAG included elevated IOP, normal gonioscopy, and glaucomatous optic disc cupping and visual field loss. POAG cosegregated with OI in the multiplex family. The multiplex family had a single nucleotide insertion (c.540_541insC) in COL1A1 resulting in a frameshift mutation and a premature termination codon. The sporadic case had a COL1A1 splice acceptor site mutation (c.2452-2A>T or IVS36-2A>T) predicted to result in a premature termination codon due to intron inclusion or a cryptic splice site. None of the glaucoma cases had mutations or sequence changes in MYOC. CONCLUSIONS: We identified two novel mutations in COL1A1 in individuals with OI type I and POAG. Thus, some mutations in COL1A1 may be causative for OI and POAG. Alternatively, susceptibility genes may interact with mutations in COL1A1 to cause POAG.

Aqueous and Plasma Levels of Phosphorylated Tau 181 in Individuals with Normal Cognition.

Background: Plasma and cerebrospinal fluid (CSF) levels of p-tau181 have been associated with Alzheimer's disease (AD). The retina and vitreous have shown measurable quantities of phosphorylated tau 181 (p-tau181). The aqueous humor, which can be collected during cataract surgery, may have measurable concentrations of p-tau181. Objective: To determine whether p-tau181 is detectable in the aqueous humor and if so, whether it is associated with other measures that might be consistent with AD such as higher plasma p-tau181 concentration and lower Montreal Cognitive Assessment (MoCA-BLIND version 7.1) score. Methods: Aqueous humor samples, blood samples, and MoCA-BLIND scores were collected from patients who did not carry a clinical diagnosis of cognitive impairment at the time of cataract surgery. Aqueous p-tau181 concentrations and plasma p-tau181 concentrations were then measured using ultra-sensitive single-molecule assay ELISA technology. A rank-transformed mixed-effects multivariate regression model was used to determine associations between aqueous concentrations, plasma concentrations, and MoCA-BLIND scores. Results: 16 eyes of 16 participants were enrolled with an average age of 71.6. Average MoCA-BLIND score was 20.6/22, average aqueous p-tau181 concentration was 6.4 pg/mL, and average plasma p-tau181 concentration was 3.1 pg/mL. Higher plasma p-tau181 was significantly associated with higher aqueous p-tau181 (p = 0.02). Aqueous p-tau181 and plasma p-tau181 were negatively associated with MoCA-BLIND scores (p = 0.005 and p = 0.001 respectively) in these patients. Conclusions: Aqueous p-tau181 is positively correlated with plasma p-tau181 and is negatively correlated with MoCA-BLIND scores. Further study in individuals with mild cognitive impairment or AD characterized by cerebrospinal fluid and volumetric MRI metrics may yield further insights.

Resident compliance with the american academy of ophthalmology preferred practice pattern guidelines for primary open-angle glaucoma.

PURPOSE: To examine resident adherence to preferred practice pattern (PPP) guidelines set up by the American Academy of Ophthalmology for follow-up care of primary open-angle glaucoma (POAG) patients. DESIGN: Retrospective chart review. PARTICIPANTS: One hundred three charts were selected for analysis from all patients with an International Classification of Diseases, Ninth Revision, code of open-angle glaucoma or its related entities who underwent a follow-up evaluation between July 2, 2003, and December 15, 2004, at the resident ophthalmology clinic in the Durham Veteran Affairs Medical Center. METHODS: Follow-up visits of POAG patients were evaluated for documentation of 19 elements in accordance to PPP guidelines. MAIN OUTCOME MEASURES: Compliance rates for the 19 elements of PPP guidelines first were averaged in all charts, and then were averaged per resident and were compared among 8 residents between their first and second years of residency. RESULTS: The overall mean compliance rate for all 19 elements was 82.6% for all charts (n = 103), 78.8% for first-year residents, and 81.7% for second-year residents. The increase from first to second year of residency was not significant (P>0.05). Documentation rates were high (>90%) for 14 elements, including all components of the physical examination and follow-up as well as most components of the examination history and management plan. Residents documented adjusting target intraocular pressure downward, local or systemic problems with medications, and impact of visual function on daily living approximately 50% to 80% of the time. Documentation rates for components of patient education were the lowest, between 5% and 16% in all charts. CONCLUSIONS: Residents' compliance with PPP guidelines for a POAG follow-up visit was very high for most elements, but documentation rates for components of patient education were poor. Adherence rates to PPP guidelines can be used as a tool to evaluate and improve resident performance during training. However, further studies are needed to establish the advantages of using PPP guidelines for resident education and to determine if such assessments can lead to improved patient care.

Resident involvement in cataract surgery at the Veterans Health Administration: complications, case complexity, and the role of experience.

PURPOSE: To characterize intraoperative complications, case complexity, and changes in complication rates with surgical experience for cataract surgeries involving residents at the Veterans Health Administration (VHA). SETTING: All VHA facilities where cataract surgery was performed. DESIGN: Multicenter, retrospective cohort study. METHODS: A retrospective review of all cataract surgeries within the VHA between July 2010 and June 2021 was conducted. Several parameters, including resident involvement, intraoperative complications, and case complexity as determined by Current Procedural Terminology codes, and use of pupil expansion or capsular support devices, were collected. Complication rates were compared between residents and attendings. RESULTS: Of 392 428 cataract surgeries completed across 108 VHA facilities, 90 504 were performed by attendings alone, while 301 924 involved a resident. Of these, 10 244 (11.3%) of attending cases were complex compared with 32 446 (10.7%) of resident cases. Pupil expansion devices were required in 8191 of attending cases (9.05%) and 31 659 (10.5%) of cases involving residents ( P < .001). Similarly, cases involving residents were more likely than attending-only cases to require a capsular support device (0.835% vs 0.586%, P < .001). Cases involving residents were more likely to have posterior capsular rupture (4.75% vs 2.58%, P < .001) and dropped nucleus (0.338% vs 0.198%, P < .001). Higher resident case volumes were associated with significantly lower complication rates for posterior capsular rupture, dropped nucleus, zonular loss, and suprachoroidal hemorrhage. CONCLUSIONS: Although residents had higher intraoperative complication rates than attendings, these rates were reduced with surgical experience. Residents were involved in a similar number of complex surgical cases as attendings.

Low prevalence of myocilin mutations in an African American population with primary open-angle glaucoma.

PURPOSE: Mutations in the myocilin gene (MYOC) are associated with primary open-angle glaucoma (POAG) in many different populations. This study represents the first large survey of MYOC mutations in an African American population. METHODS: We recruited 529 African American subjects with POAG and 270 African American control subjects in this study. A complete eye examination and blood collection was performed in all study subjects. Genomic DNA was extracted. The entire coding sequence of MYOC was amplified and sequenced using the Sanger method. Identified MYOC variants were compared with previously reported MYOC mutations. RESULTS: We identified a total of 29 MYOC variants including six potential MYOC mutations. Two mutations (Thr209Asn and Leu215Gln) are novel and are found only in cases and no controls. We also identified four previously reported MYOC mutations in cases and no controls (Tyr453MetfsX11, Gln368X, Thr377Met, and Ser393Arg). The overall frequency of glaucoma-causing MYOC mutations in our African American population with POAG was 1.4%. CONCLUSIONS: We identified two novel probable glaucoma-causing MYOC mutations (Thr209Asn and Leu215Gln). This study indicates that, despite the high prevalence of POAG, MYOC mutations are rare in the African American population.

Transition to a Night Float System in Ophthalmology Residency: Perceptions of Resident Wellness and Performance.

Purpose The purpose of this study is to characterize the influence of a new night float rotation on resident wellness and performance in the Duke University Eye Center Ophthalmology Residency Program. Methods We analyzed three classes of ophthalmology residents: one class ( n = 4) utilized the new night float rotation with no daytime clinical duties, while two senior classes ( n = 12) utilized the traditional call system wherein they had daytime and nighttime responsibilities. Residents completed a questionnaire regarding their perceptions of the night float rotation. Supervising attendings ( n = 15) were also surveyed about their perceptions of the new rotation. Results Zero of the four residents on the night float rotation reported burnout compared with 6 of 11 residents in the traditional call system. Most residents supported the adoption of the night float rotation, but this trend was less apparent among fellows and attendings. Most respondents believed the new night float rotation reduced burnout, fatigue, and work hours while increasing time for nonclinical activities. Perceived skills gained while on call were felt to be similar between the two call systems. Fellows and attendings believed residents in the night float system performed similarly or better than residents in the traditional system in indicators such as knowledge and enthusiasm. There was no significant difference in the average number of patient encounters (290.8 ± 30.5 vs. 310.7 ± 25.4, p = 0.163), phone encounters (430.8 ± 20.2 vs. 357.1 ± 90.0, p = 0.068), or average hours worked per week (57.3 ± 4.6 vs. 58.0 ± 5.7 p = 0.797) per resident between night float residents and traditional call residents. Conclusions This study shows resident support for a night float rotation in ophthalmology residency at Duke, with reductions in burnout and more time for nonclinical activities without affecting perceived clinical performance. We hope this study serves as an impetus for other ophthalmology programs considering a transition to a night float system.

Infections and glaucoma.

Glaucoma is an intraocular pressure-related ophthalmic disease with multiple causes that results in an optic neuropathy and vision loss. Intraocular pressure elevation is among its strongest risk factors. While glaucoma is mostly primary in etiology, secondary glaucoma is not infrequent. Recognizing its cause is imperative, since treatment is often different depending on the pathophysiologic mechanism. Numerous clinically relevant ophthalmic infections can result in robust inflammatory responses that may result in pressure elevation or intraocular anatomic configurations that predispose to pressure elevation. Knowing the mechanisms by which these infections can lead to glaucoma is critical in treating, and we consolidate what is currently known in regards to how infectious diseases lead to glaucoma.

Learning From the 2021 Ophthalmology Match: Virtual Residency Matching During the COVID-19 Pandemic.

Background: The effect of virtual interviews on residency match outcomes during the COVID-19 pandemic is unknown. Examining the ophthalmology match may help inform all specialties undergoing virtual interviews. Objective: To determine the impact of allopathic applicant match characteristics in the first year of the virtual residency Match process. Methods: Using the Association of University Professors of Ophthalmology match database, a retrospective review was conducted of all allopathic applicants to ophthalmology residency programs in the United States from the 2016 through the 2021 match cycles. Demographic information, interview numbers, and match outcomes were compared between the 2016-2020 (in-person) and 2021 (virtual) cycles. Results: A total of 3343 allopathic applicants were analyzed. Applicants in the 2021 Match applied to significantly more programs than 2016-2020 applicants did (78.7±23.6 vs 73.1±22.7, P<.001). Among matched and unmatched applicants, there was no significant difference in the number of interviews granted or completed. There was a significant reduction in the match rate between the 2016-2020 and 2021 Match cycles (81.3% vs 76.6%, P=.0009). A subanalysis of applicants who went to medical schools with ophthalmology residency programs (N=2308) found that the home institution match rate was significantly higher for the 2021 Match compared to the aggregate 2016-2020 Matches (26.1% vs 20.6%, respectively, P=.015). Conclusions: Significantly more applicants to ophthalmology residency programs matched at their home institutions in the 2021 virtual match cycle compared to the previous 5 years without influencing the interview numbers granted and attended.

Elevated Levels of Growth/Differentiation Factor-15 in the Aqueous Humor and Serum of Glaucoma Patients.

Dysregulated levels of growth/differentiation factor-15 (GDF15), a divergent member of the transforming growth factor-beta super family, have been found to be associated with the pathology of various diseases. In this study, we evaluated the levels of GDF15 in aqueous humor (AH) and serum samples derived from primary open-angle glaucoma (POAG) and age- and gender-matched non-glaucoma (cataract) patients to assess the plausible association between GDF15 and POAG. GDF15 levels were determined using an enzyme-linked immunosorbent assay, and data analysis was performed using the Wilcoxon rank sum test, or the Kruskal-Wallis test and linear regression. GDF15 levels in the AH (n = 105) of POAG patients were significantly elevated (by 7.4-fold) compared to cataract patients (n = 117). Serum samples obtained from a subgroup of POAG patients (n = 41) also showed a significant increase in GDF15 levels (by 50%) compared to cataract patients. GDF15 levels were elevated in male, female, African American, and Caucasian POAG patients. This study reveals a significant and marked elevation of GDF15 levels in the AH of POAG patients compared to non-glaucoma cataract control patients. Although serum GDF15 levels were also elevated in POAG patients, the magnitude of difference was much smaller relative to that found in the AH.

Long-Term Decrease of Intraocular Pressure in Rats by Viral Delivery of miR-146a.

Purpose: To evaluate the effects of miR-146a in trabecular meshwork (TM) cells and on intraocular pressure (IOP) in vivo via viral delivery of miR-146a to the anterior chamber of rat eyes. Methods: Human TM cells were transfected with miR-146 mimic or inhibitor. Some cells from each group were then subjected to cyclic mechanical stress (CMS). Other cells from each group had no force applied. Gene expression was then analyzed by quantitative polymerase chain reaction (qPCR). Replication-deficient adenovirus and lentivirus expressing miR-146a were inoculated into the anterior segment of Brown Norway rat eyes. IOP was monitored by rebound tonometry, visual acuity was evaluated by optokinetic tracking (OKT), and inflammation markers in the anterior segment were examined by slit-lamp, qPCR, and semi-thin sections. Results: miR-146 affected the expression of genes potentially involved in outflow homeostasis at basal levels and under CMS. Both lentiviral and adenoviral vectors expressing miR-146a resulted in sustained decreases in IOP ranging from 2.6 to 4.4 mmHg. Long term follow-up of rats injected with lentiviral vectors showed a sustained effect on IOP of 4.4 ± 2.9 mmHg that lasted until rats were sacrificed more than 8 months later. Eyes showed no signs of inflammation, loss of visual acuity, or other visible abnormalities. Conclusions: Intracameral delivery of miR-146a can provide a long-term decrease of IOP in rats without signs of inflammation or other visible adverse effects. Transitional Relevance: The IOP-lowering effects of miR-146 observed in rats provides a necessary step toward the development of an effective gene therapy for glaucoma in humans.

Infectious and Sterile Endophthalmitis in Eyes with Glaucoma Drainage Device from Two Large Ophthalmic Institutions.

PURPOSE: To describe the predisposing factors, presentation, management, and outcome of glaucoma drainage implant (GDI)-associated endophthalmitis. DESIGN: Retrospective chart review. PARTICIPANTS: Eyes that developed GDI-associated endophthalmitis between December 1, 2011, and December 23, 2019, at the Duke Eye Center and Cole Eye Institute. METHODS: Patient data search was performed on the basis of diagnostic codes for GDI and endophthalmitis. Endophthalmitis was defined clinically according to each physician's discretion. Eyes with infection source other than GDI were excluded. Worse vision was defined as a decrease of more than 2 Snellen lines. Data were collected on baseline demographics, systemic and ocular comorbidities, ocular surgical history, best-corrected visual acuity (BCVA), intraocular pressure (IOP), clinical presentation, eye culture results, and treatments performed. Statistical analysis included the paired t test and odds radio calculations. MAIN OUTCOME MEASURES: Visual acuity and IOP at final follow-up. RESULTS: Thirty cases (0.7%) of GDI endophthalmitis were identified among 4073 GDIs performed at the 2 institutions with active follow-up. Device exposure was identified in 20 eyes (67%) on presentation. The average follow-up after presentation was 22.4 ± 25 months. The most frequently identified organism on culture was Streptococcus pneumoniae. Same-day injection of intravitreal antibiotics was the universal first-line therapy. From baseline to final follow-up, the mean BCVA decreased from -0.84 ± 0.77 to -1.30 ± 0.93 (logarithm of the minimum angle of resolution, P = 0.02). Mean IOP did not change from baseline to final visit in the overall cohort (16.2 ± 8.2 mmHg to 14.6 ± 9.4 mmHg, P = 0.30) and in the subgroup that underwent tube explant (15.9 ± 5.5 mmHg to 15.2 ± 10.4 mmHg, P = 0.97). Eighteen of 20 tube exposure cases (90%) underwent tube explant, 1 underwent tube revision, and 1 re-epithelialized. CONCLUSIONS: Glaucoma drainage implant-associated endophthalmitis was correlated with poor visual outcome. Immediate intravitreal antibiotic delivery was a universal first-line therapy. Tube exposure was a necessary risk factor for late-onset endophthalmitis and required surgical removal or repair.

Netarsudil Improves Trabecular Outflow Facility in Patients with Primary Open Angle Glaucoma or Ocular Hypertension: A Phase 2 Study.

PURPOSE: Intraocular pressure (IOP) reduction is key to controlling primary open angle glaucoma (POAG). Pharmacotherapies for POAG or ocular hypertension (OHT) commonly lower IOP by increasing uveoscleral outflow or decreasing aqueous humor production. Netarsudil (Rhopressa), a Rho kinase inhibitor, reduces IOP by improving trabecular outflow facility, which is reduced in POAG. We investigated the effects of netarsudil on aqueous humor dynamics in patients with POAG or OHT. DESIGN: Double-masked, randomized, vehicle-controlled, Phase 2 trial. METHODS: Netarsudil 0.02% was instilled in 1 eye and vehicle into the contralateral eye of 20 patients once daily in the morning for 7 days. The primary endpoint was change in mean diurnal outflow facility on day 8 versus that on day 1 (baseline). Outflow facility was measured by using Schiøtz tonography, IOP by pneumotonometry, and episcleral venous pressure (EVP) by automated venomanometry. RESULTS: Eighteen patients (90%) completed the study. Mean diurnal outflow facility increased 0.039 versus 0.007 µL/min/mm Hg from baseline in the netarsudil- and the vehicle-treated groups, respectively (P < .001 vs. baseline for netarsudil), a treatment difference of 0.03 µL/min/mm Hg (P ≤ .001). Mean diurnal IOP change from baseline at day 8 was -4.52 mm Hg for netarsudil versus -0.98 mm Hg for vehicle, a treatment difference of -3.54 mm Hg (P < .0001). Mean diurnal EVP change from baseline was -0.79 mm Hg in the netarsudil-treated group versus 0.10 mm Hg for vehicle, a treatment difference of -0.89 mm Hg (P < .001). All patients reporting an adverse event reported conjunctival hyperemia of mild or moderate severity. CONCLUSIONS: Netarsudil acts on the conventional outflow pathway, both proximal and distal, to significantly reduce IOP in POAG and OHT by improving trabecular outflow facility and decreasing EVP.

Anti-fibrotic activity of a rho-kinase inhibitor restores outflow function and intraocular pressure homeostasis.

Glucocorticoids are widely used as an ophthalmic medication. A common, sight-threatening adverse event of glucocorticoid usage is ocular hypertension, caused by dysfunction of the conventional outflow pathway. We report that netarsudil, a rho-kinase inhibitor, decreased glucocorticoid-induced ocular hypertension in patients whose intraocular pressures were poorly controlled by standard medications. Mechanistic studies in our established mouse model of glucocorticoid-induced ocular hypertension show that netarsudil both prevented and reduced intraocular pressure elevation. Further, netarsudil attenuated characteristic steroid-induced pathologies as assessed by quantification of outflow function and tissue stiffness, and morphological and immunohistochemical indicators of tissue fibrosis. Thus, rho-kinase inhibitors act directly on conventional outflow cells to prevent or attenuate fibrotic disease processes in glucocorticoid-induced ocular hypertension in an immune-privileged environment. Moreover, these data motivate the need for a randomized prospective clinical study to determine whether netarsudil is indeed superior to first-line anti-glaucoma drugs in lowering steroid-induced ocular hypertension.