Sigma-1 receptor agonist, (+)-pentazocine, is neuroprotective in a Brown Norway rat microbead model of glaucoma.

PURPOSE: Glaucoma is a worldwide leading cause of irreversible blindness. Standard treatments lower intraocular pressure (IOP). Novel treatments to prevent optic nerve (ON) degeneration are needed. Here, we investigate the hypothesis that sigma-1 receptor (S1R) agonist (+)-pentazocine (PTZ) is neuroprotective in a Brown Norway (BN) rat, microbead model of glaucoma. METHODS: BN rats (9-11 weeks, male and female) were treated by intraperitoneal injection, 3 times per week with (+)-PTZ (2 mg/kg) or vehicle (VEH) alone. Treatment started 1 week prior to intraocular injection of polystyrene microbeads to elevate IOP. IOP was measured 2-3 times per week. Five weeks post microbead injection, rats were euthanized. ONs were removed, then fixed and processed for 63x oil, light microscope imaging of toluidine blue stained ON cross sections. To facilitate comparison of ON morphology from VEH and (+)-PTZ treated rats with similar ocular hypertensive insults, rats were assigned to low (IOP ≤15.8 mmHg), moderate (15.8 < IOP <28.0 mmHg), and high (IOP ≥28.0 mmHg) groups based on average IOP in the microbead injected eye. Axon numbers, axon density, axonal and glial areas, axon loss, and axon size distributions of naïve, bead, and contralateral ONs were assessed using QuPath program for automated image analysis. RESULTS: (+)-PTZ treatment of BN rats protected ONs from damage caused by moderate IOP elevation. Treatment with (+)-PTZ significantly reduced axon loss and glial areas, and increased axon density and axonal areas compared to ONs from VEH treated rats with moderate IOP. (+)-PTZ-mediated neuroprotection was independent of IOP lowering effects. At average IOP ≥28.0 mmHg, (+)-PTZ treatment did not provide measurable neuroprotection. ONs from contralateral eyes exhibited subtle, complex changes in response to conditions in the bead eyes. CONCLUSIONS: S1R agonist (+)-PTZ shows promise as a neuroprotective treatment for glaucoma. Future studies to understand the complex molecular mechanisms by which (+)-PTZ provides this neuroprotection are needed.

Mechanosensitive channel inhibition attenuates TGFß2-induced actin cytoskeletal remodeling and reactivity in mouse optic nerve head astrocytes.

Astrocytes within the optic nerve head undergo actin cytoskeletal rearrangement early in glaucoma, which coincides with astrocyte reactivity and extracellular matrix (ECM) deposition. Elevated transforming growth factor beta 2 (TGFß2) levels within astrocytes have been described in glaucoma, and TGFß signaling induces actin cytoskeletal remodeling and ECM deposition in many tissues. A key mechanism by which astrocytes sense and respond to external stimuli is via mechanosensitive ion channels. Here, we tested the hypothesis that inhibition of mechanosensitive channels will attenuate TGFß2-mediated optic nerve head astrocyte actin cytoskeletal remodeling, reactivity, and ECM deposition. Primary optic nerve head astrocytes were isolated from C57BL/6J mice and cell purity was confirmed by immunostaining. Astrocytes were treated with vehicle control, TGFß2 (5 ng/ml), GsMTx4 (a mechanosensitive channel inhibitor; 500 nM), or TGFß2 (5 ng/ml) + GsMTx4 (500 nM) for 48 h. FITC-phalloidin staining was used to assess the formation of f-actin stress fibers and to quantify the presence of crosslinked actin networks (CLANs). Cell reactivity was determined by immunostaining and immunoblotting for GFAP. Levels of fibronectin and collagen IV deposition were also quantified. Primary optic nerve head astrocytes were positive for the astrocyte marker GFAP and negative for markers for microglia (F4/80) and oligodendrocytes (OSP1). Significantly increased %CLAN-positive cells were observed after 48-h treatment with TGFß2 vs. control in a dose-dependent manner. Co-treatment with GsMTx4 significantly decreased %CLAN-positive cells vs. TGFß2 treatment and the presence of f-actin stress fibers. TGFß2 treatment significantly increased GFAP, fibronectin, and collagen IV levels, and GsMTx4 co-treatment ameliorated GFAP immunoreactivity. Our data suggest inhibition of mechanosensitive channel activity as a potential therapeutic strategy to modulate actin cytoskeletal remodeling within the optic nerve head in glaucoma.

Intra-population differences of apolipoproteins in the aqueous humor.

BACKGROUND: Evidence suggests that proteins related to lipid metabolism, such as apolipoproteins, play an important role in the maintenance of normal vision. While several members of the apolipoprotein family are abundant in human aqueous humor (AH), their study remains difficult due to the AH's small volume, low protein concentration, and the invasive nature of sample collection. In this study, we report the use of Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS) to discover associations between AH apolipoproteins and race, gender, and ocular structure in patients with and without primary open angle glaucoma (POAG). METHODS: AH samples were collected from 231 patients undergoing phacoemulsification or glaucoma incisional surgery at the Medical College of Georgia, Augusta University and subsequently analyzed via LC-MS/MS. The number of peptide spectrum matches (PSMs) for each protein was used as a semi-quantitative measure of relative protein levels. Parameters related to ocular structure were determined using Optical Coherence Tomography (OCT) and Heidelberg Retinal Tomography (HRT). These data sets were probed for relationships between apolipoprotein levels and POAG, demographics (gender and race), and ocular structure. RESULTS: A total of ten apolipoproteins were detected in the 231 collected AH samples, with six detected in 100% of the samples, one detected in almost 57% of the samples and three detected in less than 10% of the samples. The levels of APOA1, APOC3, and APOD were higher among POAG subjects. Stratification by gender and race revealed demographic-specific variations. The levels of five apolipoproteins (APOA1, APOA2, APOA4, APOC3, and APOD) were higher in female POAG patients, whereas no apolipoprotein levels were altered in male POAG patients. The levels of APOA1, APOA2, APOA4, and APOD were increased in glaucomatous African American patients, whereas APOE and APOH levels were decreased in glaucomatous Caucasian patients. We also found distinct associations between apolipoprotein levels and OCT and HRT parameters in patients with and without POAG. CONCLUSIONS: The intra-population variation in apolipoprotein levels highlights the heterogeneity of glaucoma as a disease, suggesting the importance of personalized treatments. Gender and race-specific alterations may be associated with higher risks of POAG in females and members of the African American population.

Identification of Estrogen Signaling in a Prioritization Study of Intraocular Pressure-Associated Genes.

Elevated intraocular pressure (IOP) is the only modifiable risk factor for primary open-angle glaucoma (POAG). Herein we sought to prioritize a set of previously identified IOP-associated genes using novel and previously published datasets. We identified several genes for future study, including several involved in cytoskeletal/extracellular matrix reorganization, cell adhesion, angiogenesis, and TGF-ß signaling. Our differential correlation analysis of IOP-associated genes identified 295 pairs of 201 genes with differential correlation. Pathway analysis identified ß-estradiol as the top upstream regulator of these genes with ESR1 mediating 25 interactions. Several genes (i.e., EFEMP1, FOXC1, and SPTBN1) regulated by ß-estradiol/ESR1 were highly expressed in non-glaucomatous human trabecular meshwork (TM) or Schlemm's canal (SC) cells and specifically expressed in TM/SC cell clusters defined by single-cell RNA-sequencing. We confirmed ESR1 gene and protein expression in human TM cells and TM/SC tissue with quantitative real-time PCR and immunofluorescence, respectively. 17ß-estradiol was identified in bovine, porcine, and human aqueous humor (AH) using ELISA. In conclusion, we have identified estrogen receptor signaling as a key modulator of several IOP-associated genes. The expression of ESR1 and these IOP-associated genes in TM/SC tissue and the presence of 17ß-estradiol in AH supports a role for estrogen signaling in IOP regulation.

Excess homocysteine upregulates the NRF2-antioxidant pathway in retinal Müller glial cells.

This study evaluated the effects of elevated homocysteine (Hcy) on the oxidative stress response in retinal Müller glial cells. Elevated Hcy has been implicated in retinal diseases including glaucoma and optic neuropathy, which are characterized by retinal ganglion cell (RGC) loss. To understand the mechanisms of Hcy-induced RGC loss, in vitro and in vivo models have been utilized. In vitro isolated RGCs are quite sensitive to elevated Hcy levels, while in vivo murine models of hyperhomocysteinemia (HHcy) demonstrate a more modest RGC loss (∼20%) over a period of many months. This differential response to Hcy between isolated cells and the intact retina suggests that the retinal milieu invokes mechanisms that buffer excess Hcy. Oxidative stress has been implicated as a mechanism of Hcy-induced neuron loss and NRF2 is a transcription factor that plays a major role in regulating cytoprotective responses to oxidative stress. In the present study we investigated whether HHcy upregulates NRF2-mediated stress responses in Müller cells, the chief retinal glial cell responsible for providing trophic support to retinal neurons. Primary Müller cells were exposed to L-Hcy-thiolactone [50µM-10mM] and assessed for viability, reactive oxygen species (ROS), and glutathione (GSH) levels. Gene/protein levels of Nrf2 and levels of NRF2-regulated antioxidants (NQO1, CAT, SOD2, HMOX1, GPX1) were assessed in Hcy-exposed Müller cells. Unlike isolated RGCs, isolated Müller cells are viable over a wide range of Hcy concentrations [50 µM - 1 mM]. Moreover, when exposed to elevated Hcy, Müller cells demonstrate decreased oxidative stress and decreased ROS levels. GSH levels increased by ∼20% within 24 h exposure to Hcy. Molecular analyses revealed 2-fold increase in Nrf2 expression. Expression of antioxidant genes Nqo1, Cat, Sod2, Hmox1, Gpx1 increased significantly. The consequences of Hcy exposure were evaluated also in Müller cells harvested from Nrf2-/- mice. In contrast to WT Müller cells, in which oxidative stress decreased upon exposure to Hcy, the Nrf2-/- Müller cells showed a significant increase in oxidative stress. Our data suggest that at least during early stages of Hhcy, a cytoprotective response may be in place, mediated in part by NRF2 in Müller cells.

Relationship between Sigma-1 receptor and BDNF in the visual system.

Glaucoma is an incurable optic neuropathy characterized by dysfunction and death of retinal ganglion cells (RGCs). Brain derived neurotrophic factor (BDNF) is an essential neurotrophin that supports RGC function and survival. Despite BDNF's importance, our knowledge of molecular mechanisms that modulate BDNF processing and secretion is incomplete. Sigma-1 receptor (S1R) is associated with increased BDNF in hippocampus and with BDNF secretion by brain-derived astrocytes and neuronal cell lines. Much less is known about the relationship between S1R and BDNF in the visual system. Here, we examine how S1R activation and deletion alter expression of mature BDNF (mBDNF) and proBDNF in retina and cultured optic nerve head (ONH) astrocytes. For S1R activation, the S1R agonist (+)-pentazocine (PTZ, 0.5 mg/kg) was administered by intraperitoneal injection to C57BL/6J mice, 3 times per week, for 5 weeks. Expression of proBDNF and mBDNF was also examined in S1R knockout and age-matched C57BL/6J mice. In vitro, cultured ONH astrocytes were treated with 3 µM PTZ for 24 h followed by collection of media and ONH astrocyte lysates. Results showed that treatment with (+)-PTZ increased mBDNF protein in both retina and hippocampus. In contrast, S1R deletion was associated with retinal mBDNF deficits. In ONH astrocytes S1R agonist (+)-PTZ significantly increased levels of secreted BDNF and proBDNF in cell lysates. These findings support a role for S1R in the modulation of BDNF levels within the retina and optic nerve head. Treatment with S1R agonists might provide benefit in diseases such as glaucoma by increasing BDNF levels from endogenous sources.

The Role of Sigma 1 Receptor as a Neuroprotective Target in Glaucoma.

The role of sigma 1 receptor (S1R) in glaucoma is emerging as a promising field of study. Glaucoma is an optic neuropathy that shares common pathogenic mechanisms with other neurodegenerative diseases such as Alzheimer's and Parkinson's disease . S1R modulates multiple cellular functions associated with neurodegeneration . These include Ca2+ ion homeostasis, endoplasmic reticulum (ER) and oxidative stress , survival signaling pathways, neurotrophin secretion, and glial activation. S1R may also have neurorestorative properties including enhancement of neuronal plasticity and neurite outgrowth. Recent studies using agonists for S1R within the eye provide hope that it could be a therapeutic target for glaucoma. Understanding the role of S1R in glaucoma may help us to stop the progression of this sight threatening disease.

Comparative analysis of human tear fluid and aqueous humor proteomes.

PURPOSE: Technological advancements allowing for the analysis of low-volume samples have led to the investigation of human tear fluid and aqueous humor (AH) as potential biomarker sources. However, acquiring AH samples poses significant challenges, making human tear fluid a more accessible alternative. This study aims to compare the protein compositions of these two biofluids to evaluate their suitability for biomarker discovery. METHODS: Paired tear and AH samples were collected from 20 patients undergoing cataract surgery. Tear samples were collected using Schirmer strips prior to surgery, and AH samples were collected from the anterior chamber immediately after corneal incision. Proteins were extracted and analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). RESULTS: A total of 481 proteins were identified in greater than 50% of the tear samples, and 191 proteins were detected in greater than 50% of the AH samples. Of these proteins, 82 were found to be common between the two biofluids, with ALB, LTF, TF, LCN1, and IGKC being the most abundant. CONCLUSION: Although tear fluid and the AH are functionally independent and physically separated, many of the proteins detected in AH were also detected in tears. This direct comparison of the proteomic content of tear fluid and AH may aid in further investigation of tear fluid as a source of readily accessible biomarkers for various human diseases.

AHP DB: a reference database of proteins in the human aqueous humor.

The aqueous humor (AH) is a low-viscosity biofluid that continuously circulates from the posterior chamber to the anterior chamber of the eye. Recent advances in high-resolution mass-spectrometry workflows have facilitated the study of proteomic content in small-volume biofluids like AH, highlighting the potential clinical implications of the AH proteome. Nevertheless, in-depth investigations into the role of AH proteins in ocular diseases have encountered challenges due to limited accessibility to these workflows, difficulties in large-scale AH sample collection and the absence of a reference AH proteomic database. In response to these obstacles, and to promote further research on the involvement of AH proteins in ocular physiology and pathology, we have developed the web-based Aqueous Humor Proteomics Database (AHP DB). The current version of AHP DB contains proteomic data from 307 human AH samples, which were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The database offers comprehensive information on 1683 proteins identified in the AH samples. Furthermore, relevant clinical data are provided for each analyzed sample. Researchers also have the option to download these datasets individually for offline use, rendering it a valuable resource for the scientific community. Database URL: https://ahp.augusta.edu/.

Defining the ligand-dependent proximatome of the sigma 1 receptor.

Sigma 1 Receptor (S1R) is a therapeutic target for a wide spectrum of pathological conditions ranging from neurodegenerative diseases to cancer and COVID-19. S1R is ubiquitously expressed throughout the visceral organs, nervous, immune and cardiovascular systems. It is proposed to function as a ligand-dependent molecular chaperone that modulates multiple intracellular signaling pathways. The purpose of this study was to define the S1R proximatome under native conditions and upon binding to well-characterized ligands. This was accomplished by fusing the biotin ligase, Apex2, to the C terminus of S1R. Cells stably expressing S1R-Apex or a GFP-Apex control were used to map proximal proteins. Biotinylated proteins were labeled under native conditions and in a ligand dependent manner, then purified and identified using quantitative mass spectrometry. Under native conditions, S1R biotinylates over 200 novel proteins, many of which localize within the endomembrane system (endoplasmic reticulum, Golgi, secretory vesicles) and function within the secretory pathway. Under conditions of cellular exposure to either S1R agonist or antagonist, results show enrichment of proteins integral to secretion, extracellular matrix formation, and cholesterol biosynthesis. Notably, Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) displays increased binding to S1R under conditions of treatment with Haloperidol, a well-known S1R antagonist; whereas Low density lipoprotein receptor (LDLR) binds more efficiently to S1R upon treatment with (+)-Pentazocine ((+)-PTZ), a classical S1R agonist. Furthermore, we demonstrate that the ligand bound state of S1R correlates with specific changes to the cellular secretome. Our results are consistent with the postulated role of S1R as an intracellular chaperone and further suggest important and novel functionalities related to secretion and cholesterol metabolism.

Complement System Proteins in the Human Aqueous Humor and Their Association with Primary Open-Angle Glaucoma.

This study discovers the complement protein profile in the aqueous humor (AH) of human subjects and investigates its association with primary open-angle glaucoma (POAG) pathogenesis. Among the 32 complement proteins identified, 22 were highly abundant and detected in more than 50% of AH samples. The most predominant active complement proteins in the AH are C3, C4B, C4A, CFB, CFD, and C9. Additionally, the most prevalent complement regulators and receptors include CLU, SERPING1, F2, CFH, CFI, and VTN. Significant alterations in complement proteins were observed in individuals with POAG compared to those with cataracts. Specifically, complement protein F2 was upregulated, while C8G, C6, and CFH were downregulated in POAG samples. Stratification of the samples by race and sex revealed distinct alterations of complement proteins in patients with POAG. In the African American cohort, five complement proteins (C4A, C4B, F2, C7, and C3) were upregulated in POAG compared to cataract patients. In the Caucasian cohort, eight complement proteins (C3, SERPING1, CFI, CLU, CFHR1, C8G, C6, and CFH) were downregulated in the POAG samples compared to the cataract samples. Within the male cohort, three complement proteins (CLU, C6, and CFH) were downregulated in POAG patients compared to those with cataracts. Whereas, within the female cohort, two complement proteins (C4B and F2) were upregulated and one (C8G) downregulated in the POAG samples when compared to cataracts. Discerning these changes in the AH complement protein profile will assist in the development of tailored therapies to modulate the complement system for managing ocular disorders. These insights may also lead to novel biomarkers for diagnosing and monitoring disease progression.

Proteomic similarities in steroid responsiveness in normal and glaucomatous trabecular meshwork cells.

PURPOSE: Glucocorticoids (GCs) are common anti-inflammatory agents that can cause ocular hypertension and secondary glaucoma as a consequence of impaired aqueous humor outflow through the trabecular meshwork (TM). Mechanisms of GC-signaling are complex and poorly understood. To better understand GC-signaling in the eye, we tested the hypothesis that common mechanisms of steroid responsiveness exist in TM cells from normal and glaucomatous donors. METHODS: Four primary cultures of human TM cells from normal and glaucomatous donors were treated with or without dexamethasone (Dex) for 10 days, then cellular proteins were extracted, identified and quantified by liquid chromatography tandem mass spectrometry (LC MS/MS) iTRAQ (isobaric tags for relative and absolute quantitation) technology. RESULTS: A total of 718 proteins were quantified. Dex-treatment significantly altered the abundance of 40 proteins in ≥3 cell samples, 37 of which have not previously been associated with GC-signaling in TM cells. Most steroid responsive proteins were changed in all four TM cells analyzed, both normal and glaucomatous. GC-induced proteomic changes support remodeling of the extracellular matrix, disorganization of the cytoskeleton/cell-cell interactions, and mitochondrial dysfunction. Such physiologic consequences appear common to those induced in TM cells by transforming growth factor-ß(2), another putative contributor to ocular hypertension and glaucoma pathology. CONCLUSIONS: The results expand the repertoire of TM proteins involved in GC-signaling, demonstrate common consequences of GC-signaling in normal and glaucomatous TM cells, and reveal similarities in proteomic changes induced by steroids and TGFß(2) in normal and glaucomatous TM cells. Finally, the data contributes to a TM quantitative proteomic database.

Sigma 1 Receptor Contributes to Astrocyte-Mediated Retinal Ganglion Cell Protection.

Purpose: Sigma 1 receptor (S1R) is expressed in retinal ganglion cells (RGCs) and astrocytes, and its activation is neuroprotective. We evaluated the contribution of S1R within optic nerve head astrocytes (ONHAs) to growth and survival of RGCs in vitro. Methods: Wild-type (WT) RGCs and WT or S1R knockout (S1R KO) ONHAs were cocultured for 2, 4, or 7 days. Total and maximal neurite length, neurite root, and extremity counts were measured. Cell death was measured using a TUNEL assay. Signal transducer and activator of transcription 3 phosphorylation levels were evaluated in ONHA-derived lysates by immunoblotting. Results: The coculture of WT RGCs with WT or S1R KO ONHAs increased the total and maximal neurite length. Neurite root and extremity counts increased at 4 and 7 days when WT RGCs were cocultured with WT or S1R KO ONHAs. At all timepoints, the total and maximal neurite length decreased for WT RGCs in coculture with S1R KO ONHAs compared with WT ONHAs. Root and extremity counts decreased for WT RGCs in coculture with S1R KO ONHAs compared with WT ONHAs at 2 and 7, but not 4 days. RGC apoptosis increased in S1R KO ONHA coculture and S1R KO-conditioned medium, compared with WT ONHA coculture or WT-conditioned medium. S1R KO ONHA-derived lysates showed decreased phosphorylated signal transducer and activator of transcription 3 levels compared with WT ONHA-derived lysates. Conclusions: The absence of S1R within ONHAs has a deleterious effect on RGC neurite growth and RGC survival, reflected in analysis of WT RGC + S1R KO ONHA indirect cocultures. The data suggest that S1R may enhance ganglion cell survival via glia-mediated mechanisms.

The Relative Citation Ratio: Examining a Novel Measure of Research Productivity among Southern Academic Ophthalmologists.

PurposeTo analyze research productivity, as assessed by the National Institutes of Health-supported relative citation ratio (RCR), for a cohort of Southern academic ophthalmologists.DesignA descriptive and cross-sectional design was used. Data on gender, academic rank (assigned as an assistant professor, associate professor, professor, or degrees, and career duration were collected using online resources. Research yield was quantified using mean and weighted RCR data queried from the iCite database. Significant between-group differences were calculated using the Mann-Whitney U-test and the Kruskal-Wallis test.SettingsPracticing academic ophthalmologists at Accreditation Council for Graduate Medical Education-accredited ophthalmology programs in the Southern United States (n = 1018).ResultsFor all Southern academic ophthalmologists, median mean RCR was 0.90 (IQR 0.18-1.71) and median weighted RCR was 5.12 (IQR 0.34-33.18). Advanced academic rank and PhD acquisition were significantly associated with increased mean and weighted RCR. After exclusion of faculty within the "other" category, median mean RCR was 1.12 (IQR 0.54-1.80) and median weighted RCR was 11.65 (IQR 2.03-45.58). Furthermore, effects of career duration and gender emerged. Ophthalmologists with longer careers had significantly higher mean and weighted RCR than their younger counterparts. Males had significantly higher mean and weighted RCR than females.ConclusionsAcademic rank and attainment of a PhD degree were correlated with increased research productivity. When analyses focused exclusively on faculty not in the "other" subgroup, male gender, and lengthier career were associated with increased mean and weighted RCR, the former of which potentially highlights differences in professional advancement between genders.

Optical coherence tomography angiography and Humphrey visual field in patients with obstructive sleep apnea.

STUDY OBJECTIVES: To determine if obstructive sleep apnea syndrome (OSAS) predisposes patients to glaucoma and macular disease due to vascular compromise by evaluating retinal and optic nerve vasculature and function using optical coherence tomography angiography and Humphrey visual field testing, respectively. METHODS: In this prospective, observational, cross-sectional study 45 patients undergoing polysomnography ordered per standard of care were selected and stratified based on apnea-hypopnea index (AHI). Medical history, visual acuity testing, 24-2 Humphrey visual field, intraocular pressure measurement, and optical coherence tomography angiography studies of the macular and peripapillary retina were obtained. Correlations between polysomnography parameters and imaging data were analyzed. RESULTS: The radial peripapillary capillary vascular density demonstrated no relationship to AHI (95% confidence interval [CI] [-0.026,0.038]) or severity of OSAS (95% CI: [-0.772, 3.648]) for moderate OSAS compared to mild/normal and (-1.295, 3.1421) for severe compared to mild/normal. Optical coherence tomography angiography superficial parafoveal vascular density (95% CI: [-0.068,0.011], deep parafoveal vascular density (95% CI: [-0.080,0.009]), and foveal avascular zone (95% CI: [-0.001, 0.001]) showed no statistically significant relationship to AHI or OSAS severity after controlling for confounders. Optical coherence tomography retinal nerve fiber layer thickness increased with AHI (P = .014), but there was no statistically significant correlation with OSAS severity with retinal nerve fiber layer thickness (95% CI: [-12.543, 6.792] for moderate comparing to normal and [-2.883, 16.551] for severe comparing to normal). Visual field parameters were unaffected by OSAS (95% CI: mean deviation [-0.21,0.29], pattern standard deviation: [-0.351, 0.121], visual field index: [-0.166, 0.329]). Optical coherence tomography choroidal thickness showed a statistically significant decrease when OSAS was grouped by severity (P = .0092) but did not correlate with AHI (P = .129, 95% CI: [-1.210, 0.095]). CONCLUSIONS: The severity of OSAS did not show a statistically significant effect on parameters associated with glaucoma or macular vascular disease. Larger cohorts may be required to determine the physiologic consequences of OSAS on the macular and optic nerve vasculature, structure, and function. CITATION: Davanian A, Williamson L, Taylor C, et al. Optical coherence tomography angiography and Humphrey visual field in patients with obstructive sleep apnea. J Clin Sleep Med 2022;18(9):2133-2142.

Intraocular pressure outcome of patients with fluocinolone acetonide intravitreal implant for noninfectious uveitis.

PURPOSE: To evaluate the intraocular pressure (IOP) outcomes of patients with noninfectious posterior uveitis treated with a fluocinolone acetonide (FA) intravitreal implant over an 8-year period. DESIGN: Retrospective clinical case series. PARTICIPANTS: Forty-seven eyes of 35 patients. METHODS: Retrospective review of medical records of all patients receiving FA implants between June 2001 and March 2009 was performed. Data were pooled to record visual acuity (VA) and to characterize the incidence and outcome of glaucoma surgical intervention. MAIN OUTCOME MEASURES: Incidence of glaucoma surgery and IOP before and after glaucoma surgical intervention. Visual acuity before and after FA implant placement. RESULTS: Nineteen of 42 eyes (45%) receiving FA implants over the course of the study period required glaucoma surgical intervention. Success of IOP-lowering surgery was achieved in 94%, 94%, and 92% of eyes at 6, 12, and 24 months postoperatively. No patient lost more than 1 line of VA. There was an average 2-line gain of acuity at 3 years after FA implant placement for those patients who underwent IOP-lowering surgery. CONCLUSIONS: Patients receiving FA implants have a significant risk of increased IOP that frequently necessitates glaucoma surgery. Glaucoma surgery, when necessary, offers an effective method to decrease IOP. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Immunocytochemical evidence of Tulp1-dependent outer segment protein transport pathways in photoreceptor cells.

Tulp1 is a protein of unknown function exclusive to rod and cone photoreceptor cells. Mutations in the gene cause autosomal recessive retinitis pigmentosa in humans and photoreceptor degeneration in mice. In tulp1-/- mice, rod and cone opsins are mislocalized, and rhodopsin-bearing extracellular vesicles accumulate around the inner segment, indicating that Tulp1 is involved in protein transport from the inner segment to the outer segment. To investigate this further, we sought to define which outer segment transport pathways are Tulp1-dependent. We used immunohistochemistry to examine the localization of outer segment proteins in tulp1-/- photoreceptors, prior to retinal degeneration. We also surveyed the condition of inner segment organelles and rhodopsin transport machinery proteins. Herein, we show that guanylate cyclase 1 and guanylate cyclase activating proteins 1 and 2 are mislocalized in the absence of Tulp1. Furthermore, arrestin does not translocate to the outer segment in response to light stimulation. Additionally, data from the tulp1-/- retina adds to the understanding of peripheral membrane protein transport, indicating that rhodopsin kinase and transducin do not co-transport in rhodopsin carrier vesicles and phosphodiesterase does not co-transport in guanylate cyclase carrier vesicles. These data implicate Tulp1 in the transport of selective integral membrane outer segment proteins and their associated proteins, specifically, the opsin and guanylate cyclase carrier pathways. The exact role of Tulp1 in outer segment protein transport remains elusive. However, without Tulp1, two rhodopsin transport machinery proteins exhibit abnormal distribution, Rab8 and Rab11, suggesting a role for Tulp1 in vesicular docking and fusion at the plasma membrane near the connecting cilium.

Sigma 1 Receptor Modulates Optic Nerve Head Astrocyte Reactivity.

Purpose: Stimulation of Sigma 1 Receptor (S1R) is neuroprotective in retina and optic nerve. S1R is expressed in both neurons and glia. The purpose of this work is to evaluate the ability of S1R to modulate reactivity responses of optic nerve head astrocytes (ONHAs) by investigating the extent to which S1R activation alters ONHA reactivity under conditions of ischemic cellular stress. Methods: Wild type (WT) and S1R knockout (KO) ONHAs were derived and treated with vehicle or S1R agonist, (+)-pentazocine ((+)-PTZ). Cells were subjected to six hours of oxygen glucose deprivation (OGD) followed by 18 hours of re-oxygenation (OGD/R). Astrocyte reactivity responses were measured. Molecules that regulate ONHA reactivity, signal transducer and activator of transcription 3 (STAT3) and nuclear factor kappa B (NF-kB), were evaluated. Results: Baseline glial fibrillary acidic protein (GFAP) levels were increased in nonstressed KO ONHAs compared with WT cultures. Baseline cellular migration was also increased in nonstressed KO ONHAs compared with WT. Treatment with (+)-PTZ increased cellular migration in nonstressed WT ONHAs but not in KO ONHAs. Exposure of both WT and KO ONHAs to ischemia (OGD/R), increased GFAP levels and cellular proliferation. However, (+)-PTZ treatment of OGD/R-exposed ONHAs enhanced GFAP levels, cellular proliferation, and cellular migration in WT but not KO cultures. The (+)-PTZ treatment of WT ONHAs also enhanced the OGD/R-induced increase in cellular pSTAT3 levels. However, treatment of WT ONHAs with (+)-PTZ abrogated the OGD/R-induced rise in NF-kB(p65) activation. Conclusions: Under ischemic stress conditions, S1R activation enhanced ONHA reactivity characteristics. Future studies should address effects of these responses on RGC survival.

Survey of Microinvasive Glaucoma Surgery and Other Glaucoma Surgical Experience among United States Ophthalmology Residency Programs.

Purpose The aim of the study is to assess the state of glaucoma surgical training in United States ophthalmology residency programs, including experience with microinvasive glaucoma surgery (MIGS). Design The design of the study is anonymous, internet-based national survey. Participants Current United States ophthalmology residents of residency programs accredited by the Accreditation Council for Graduate Medical Education (ACGME). Methods An anonymous survey link was emailed to all 120 accredited United States ophthalmology residency programs inviting residents to participate in an assessment of residency glaucoma surgical experience. Survey responses were collected between January 21, 2019 and March 4, 2019 and analyzed using descriptive statistics. Main Outcome Measures The main outcomes of the study are demographic information, practice intentions, and anticipated primary surgical experience with ACGME-required glaucoma procedures and MIGS procedures, as self-reported by U.S. ophthalmology residents. Results Of the estimated 1,479 U.S. ophthalmology residents, 161 residents participated (10.9%). A total of 118 residents (73.2%) reported any degree of anticipated MIGS primary surgical experience during residency, with the iStent being the most familiar technique. The likelihood of any anticipated MIGS experience during residency was not significantly different by geographic region ( p = 0.16), however, anticipated volume varied significantly ( p = 0.037). Of the 113 respondents who reported an intention to manage glaucoma surgically in their eventual practice, 25 (22.1%) reported no anticipated primary MIGS experience during residency. 73.3% of residents anticipating MIGS experience anticipated 0 to 10 cases, with 42.9% anticipating less than 5 cases as primary surgeon. Conclusion MIGs are not a required component of the glaucoma surgical curriculum for U.S. ophthalmology residents. Although the majority of ophthalmology residents surveyed intend to manage glaucoma surgically in eventual practice, most receive minimal experience with these novel techniques during residency. Surgical training is variable by geographic region.

Association of vitamin D with incident glaucoma: findings from the Women's Health Initiative.

The relationship between vitamin D and glaucoma is controversial. The objective of this study was to examine women from the Women's Health Initiative (WHI) to determine if there is an association between vitamin D and incident glaucoma in postmenopausal women. We examined the association between dietary vitamin D intake, vitamin D supplements and serum 25 hydroxyvitamin D (25(OH)D) levels and the risk of developing glaucoma. 143,389 postmenopausal women from the WHI including a subset with serum 25(OH) D measurements were examined to determine the association of dietary, supplemental and serum levels of vitamin D to the development of glaucoma. Dietary intakes of vitamin D, use of vitamin D supplements and serum levels of 25(OH) D were predictors examined for the main outcome of incident glaucoma. In multivariable models adjusted for demographic, clinical variables and medication use, dietary vitamin D, vitamin D supplements, total vitamin D intake (diet plus supplements) and serum 25 (OH) D measurements were not significantly associated with incident glaucoma. In the CaD placebo-controlled intervention clinical trial, there was also no association in the active intervention arm with glaucoma. We conclude that dietary vitamin D intake, supplements and serum levels are not significantly related to the risk of developing glaucoma in postmenopausal women.