Evidence for Complementary and Alternative Therapies to Treat Glaucoma.

Complementary and alternative medicine is used by approximately 5% of patients with glaucoma, and examples include marijuana, Ginkgo biloba extract, bilberry fruit extract, and acupuncture. Systemic marijuana is not beneficial for glaucoma due to the short duration of action, the lack of evidence that it alters disease progression, and its negative side effect profile. Drops that affect the cannabinoid pathway are still being studied. Ginkgo biloba and bilberry fruit extracts have been shown to decrease oxidative stress and improve perfusion of the optic nerve head. However, these findings are inconsistent throughout the literature and the studies are small, which makes the overall evidence weak. There is no evidence that acupuncture alters glaucoma disease progression or causes a sustained decrease in intraocular pressure. In summary, the literature suggests that there are transient and/or theoretical benefits of complementary and alternative medicine for glaucoma care; however, the overall evidence to support their use is weak.

Two pediatric cases of reticular corneal epithelial edema associated with netarsudil.

Purpose: To report two pediatric cases of reticular corneal epithelial edema associated with the use of netarsudil ophthalmic solution 0.02%. Observations: In Case 1, a six-year-old male with glaucoma following cataract surgery was treated with netarsudil for thirteen months and developed diffuse reticular corneal epithelial edema on post-operative day one after undergoing transscleral diode cyclophotocoagulation for persistently elevated intraocular pressures. In Case 2, a three-month-old male with bilateral ocular hypertension developed unilateral inferior reticular corneal epithelial edema five weeks after initiation of netarsudil, which had been discontinued in the fellow eye two weeks prior. In both cases, the reticular epithelial edema resolved following cessation of netarsudil. Conclusions and Importance: Netarsudil-associated reticular corneal epithelial edema can occur in infants and young children.

Tolerability and Functionality of a Wireless 24-Hour Ocular Telemetry Sensor in African American Glaucoma Patients.

PURPOSE: The purpose of the study was to evaluate the tolerability and functionality of a wireless ocular telemetry sensor in African American patients with glaucoma. MATERIALS AND METHODS: In this prospective, observational cohort study, 20 African American patients with primary open angle glaucoma (POAG) were evaluated at the University of Colorado Eye Center. Before lens placement, patients recorded ocular comfort and underwent a baseline eye exam. Following the exam, patients were fitted with a SENSIMED Triggerfish contact lens sensor and data recording device. Patients were sent home and instructed to record their activities in a journal and return in 24 hours. Repeat exams were performed at various time points in clinic before and after lens removal. RESULTS: All 20 patients retained the lens for the 24-hour study period. The patient reported comfort was excellent, with a nadir of mean recorded comfort of 7.05/10. Significant clinical changes were noted in lid/conjunctival erythema, BCVA, refraction, and pachymetry over the course of lens wear. The majority of these changes were improved or resolved by 1 hour after lens removal. Voltage output was significantly greater nocturnally than diurnally (184.79 mV and 71.48 mV, respectively; P<0.0001). There was no significant change in signal variability or slope over the entire duration of the sleep/wake period based on sleep. CONCLUSIONS: The wireless ocular sensor is well tolerated over a 24-hour period in African American patients with POAG despite transient changes in visual acuity and conjunctival erythema. Clinically usable 24-hour profiles were generated for all patients, with voltage output increasing significantly during periods of sleep.

Revisiting the Cornea and Trabecular Meshwork Junction With 2-Photon Excitation Fluorescence Microscopy.

PURPOSE: To investigate the collagen and elastin architecture at the junction of the human cornea and trabecular meshwork (TM). METHODS: The cornea, TM, and ciliary body (CB) tendons of unfixed human corneal buttons were imaged with an inverted 2-photon excited fluorescence microscope (FluoView FV-1000; Olympus, Central Valley, PA). The laser (Ti:sapphire) was tuned to 850 nm for 2-photon excitation. Backscatter signals of second harmonic generation and autofluorescence were collected through a 425/30-nm emission filter and a 525/45-nm emission filter, respectively. The second harmonic generation signal corresponds to collagen fibers, and the autofluorescence signal corresponds to elastin-containing tissue. Tissue structure representations were obtained through software-generated reconstructions of consecutive and overlapping (z-stack) images through a relevant sample depth. RESULTS: Collagen-rich CB tendons insert into the cornea between Descemet membrane (DM) and posterior stroma along with elastin fibers originating from the TM. The CB tendons directly abut DM, and their insertion narrows as they course centrally in the cornea, giving a wedge appearance to these parallel collagen fibers. Approximately 260 µm centrally from the edge of DM, the CB tendons fan out and merge with pre-DM collagen. As the CB tendons enter the cornea, they form a dense collagenous comb-like structure orthogonal to the edge of DM and supported by a delicate elastin network of interwoven fibers originating from the TM. CONCLUSIONS: Two-photon excited fluorescence microscopy has improved our understanding of the peripheral corneal architecture. CB tendon insertions in this region may contribute to the radial tears encountered when preparing DM endothelial keratoplasty grafts.

Details of the Collagen and Elastin Architecture in the Human Limbal Conjunctiva, Tenon's Capsule and Sclera Revealed by Two-Photon Excited Fluorescence Microscopy.

PURPOSE: To investigate the architecture and distribution of collagen and elastin in human limbal conjunctiva, Tenon's capsule, and sclera. METHODS: The limbal conjunctiva, Tenon's capsule, and sclera of human donor corneal buttons were imaged with an inverted two-photon excited fluorescence microscope. No fixation process was necessary. The laser (Ti:sapphire) was tuned at 850 nm for two-photon excitation. Backscatter signals of second harmonic generation (SHG) and autofluorescence (AF) were collected through a 425/30-nm and a 525/45-nm emission filter, respectively. Multiple, consecutive, and overlapping (z-stack) images were acquired. Collagen signals were collected with SHG, whereas elastin signals were collected with AF. RESULTS: The size and density of collagen bundles varied widely depending on depth: increasing from conjunctiva to sclera. In superficial image planes, collagen bundles were <10 µm in width, in a loose, disorganized arrangement. In deeper image planes (episclera and superficial sclera), collagen bundles were thicker (near 100 µm in width) and densely packed. Comparatively, elastin fibers were thinner and sparse. The orientation of elastin fibers was independent of collagen fibers in superficial layers; but in deep sclera, elastin fibers wove through collagen interbundle gaps. At the limbus, both collagen and elastin fibers were relatively compact and were distributed perpendicular to the limbal annulus. CONCLUSIONS: Two-photon excited fluorescence microscopy has enabled us to understand in greater detail the collagen and elastin architecture of the human limbal conjunctiva, Tenon's capsule, and sclera.

Role of nitric oxide in murine conventional outflow physiology.

Elevated intraocular pressure (IOP) is the main risk factor for glaucoma. Exogenous nitric oxide (NO) decreases IOP by increasing outflow facility, but whether endogenous NO production contributes to the physiological regulation of outflow facility is unclear. Outflow facility was measured by pressure-controlled perfusion in ex vivo eyes from C57BL/6 wild-type (WT) or transgenic mice expressing human endothelial NO synthase (eNOS) fused to green fluorescent protein (GFP) superimposed on the endogenously expressed murine eNOS (eNOS-GFPtg). In WT mice, exogenous NO delivered by 100 µM S-nitroso-N-acetylpenicillamine (SNAP) increased outflow facility by 62 ± 28% (SD) relative to control eyes perfused with the inactive SNAP analog N-acetyl-d-penicillamine (NAP; n = 5, P = 0.016). In contrast, in eyes from eNOS-GFPtg mice, SNAP had no effect on outflow facility relative to NAP (-9 ± 4%, P = 0.40). In WT mice, the nonselective NOS inhibitor N(G)-nitro-l-arginine methyl ester (l-NAME, 10 µM) decreased outflow facility by 36 ± 13% (n = 5 each, P = 0.012), but 100 µM l-NAME had no detectable effect on outflow facility (-16 ± 5%, P = 0.22). An eNOS-selective inhibitor (cavtratin, 50 µM) decreased outflow facility by 19 ± 12% in WT (P = 0.011) and 39 ± 25% in eNOS-GFPtg (P = 0.014) mice. In the conventional outflow pathway of eNOS-GFPtg mice, eNOS-GFP expression was localized to endothelial cells lining Schlemm's canal and the downstream vessels, with no apparent expression in the trabecular meshwork. These results suggest that endogenous NO production by eNOS within endothelial cells of Schlemm's canal or downstream vessels contributes to the physiological regulation of aqueous humor outflow facility in mice, representing a viable strategy to more successfully lower IOP in glaucoma.

4-Phenylbutyrate stimulates Hsp70 expression through the Elp2 component of elongator and STAT-3 in cystic fibrosis epithelial cells.

Sodium 4-phenylbutyrate (4PBA) corrects trafficking of ΔF508-CFTR in Cystic Fibrosis (CF) epithelia, which is hypothesized to, at least in part, result from increased expression of Hsp70 (stress-induced 70 kDa heat shock protein). To identify other 4PBA-regulated proteins that may promote correction of ΔF508 trafficking, we performed differential display RT-PCR on mRNA from IB3-1 CF bronchiolar epithelial cells treated for 0-24 h with 1 mM 4PBA. In this screen, a STAT-3 (signal transducer and activator of transcription-3)-interacting protein, StIP-1 that regulates STAT-3 activation had transiently increased expression. StIP-1 is identical to Elongator protein 2 (Elp2), a component of the Elongator complex that regulates RNA polymerase II. Previous studies have suggested that Elongator regulates Hsp70 mRNA transcription, and that the Hsp70 promoter contains functional STAT-3-binding sites. We therefore tested the hypothesis that 4PBA increases Hsp70 expression by an Elongator- and STAT-3-dependent mechanism. 4PBA treatment of IB3-1 CF bronchiolar epithelial cells caused transiently increased expression of Hsp70 protein, as well as Elp2 protein and mRNA. Elp2 depletion by transfection of small interfering RNAs, reduced both Elp2 and Hsp70 protein expression. 4PBA also caused transient activation of STAT-3, and increased abundance of nuclear proteins that bind to the STAT-3-responsive element of the Hsp70 promoter. Luciferase reporter assays demonstrated that both Elp2 overexpression and 4PBA increase Hsp70 promoter activity, while Elp2 depletion blocked the ability of 4PBA to stimulate Hsp70 promoter activity. Together, these data suggest that Elp2 and STAT-3 mediate, at least in part, the stimulation of Hsp70 expression by 4PBA.