All

Kovacs K, Marra KV, Yu G, Wagley S, Ma J, Teague GC, Nandakumar N, Lashkari K, Arroyo JG. Angiogenic and Inflammatory Vitreous Biomarkers Associated With Increasing Levels of Retinal Ischemia. Invest Ophthalmol Vis Sci 2015;56(11):6523-30.Abstract

PURPOSE: To characterize the angiogenic and inflammatory vitreous biomarker profiles in a spectrum of ischemic retinopathies, including neovascular glaucoma. METHODS: This institutional review board-approved study retrospectively analyzed 80 undiluted vitreous samples obtained during pars vitrectomy. The specimens were frozen (-80°C) and sent for concentration analysis of 34 proteins by Bio-Plex Pro assays. Specimens were divided into four groups: patients undergoing epiretinal membrane (ERM) peeling and/or macular hole (MH) surgery with no history of diabetes (non-DM group), patients undergoing ERM peeling, and/or MH surgery with a history of diabetes (DM group), patients with proliferative diabetic retinopathy (PDR group), and patients with neovascular glaucoma (NVG group). Parametric and nonparametric analyses of demographics and cytokine levels were performed using SPSS. RESULTS: There were no significant differences in demographics among cohorts. Numerous proteins were significantly elevated between non-DM and DM (G-CSF, sCD40L, Endoglin, IL-6, placental growth factor [PlGF], VEGF-D), DM and PDR (leptin, IL-8, PlGF, VEGF-A), and PDR and NVG (G-CSF, leptin, TIE-2, sCD40L, EGF, HB-EGF, IL-6, IL-8, PlGF, TNF-α). Only PlGF was significantly elevated between each successive cohort. The most potent drivers of NVG were PlGF, VEGF-A, IL-6, and IL-8. CONCLUSIONS: While the role of angioproliferative growth factors is well documented in ischemic retinopathy, our study delineates the importance of inflammatory and previously underreported angiogenic proteins. It also demonstrates a significant incremental increase in certain factors with increasing levels of ischemia. Both of these findings may guide the development of future therapies for ischemic retinopathies.

Srinivasan S, Chitalia V, Meyer RD, Hartsough E, Mehta M, Harrold I, Anderson N, Feng H, Smith LEH, Jiang Y, Costello CE, Rahimi N. Hypoxia-induced expression of phosducin-like 3 regulates expression of VEGFR-2 and promotes angiogenesis. Angiogenesis 2015;18(4):449-62.Abstract

Expression and activation of vascular endothelial growth factor receptor 2 (VEGFR-2) by VEGF ligands are the main events in the stimulation of pathological angiogenesis. VEGFR-2 expression is generally low in the healthy adult blood vessels, but its expression is markedly increased in the pathological angiogenesis. In this report, we demonstrate that phosducin-like 3 (PDCL3), a recently identified chaperone protein involved in the regulation of VEGFR-2 expression, is required for angiogenesis in zebrafish and mouse. PDCL3 undergoes N-terminal methionine acetylation, and this modification affects PDCL3 expression and its interaction with VEGFR-2. Expression of PDCL3 is regulated by hypoxia, the known stimulator of angiogenesis. The mutant PDCL3 that is unable to undergo N-terminal methionine acetylation was refractory to the effect of hypoxia. The siRNA-mediated silencing of PDCL3 decreased VEGFR-2 expression resulting in a decrease in VEGF-induced VEGFR-2 phosphorylation, whereas PDCL3 over-expression increased VEGFR-2 protein. Furthermore, we show that PDCL3 protects VEGFR-2 from misfolding and aggregation. The data provide new insights for the chaperone function of PDCL3 in angiogenesis and the roles of hypoxia and N-terminal methionine acetylation in PDCL3 expression and its effect on VEGFR-2.

Wu J, Cho E, Willett WC, Sastry SM, Schaumberg DA. Intakes of Lutein, Zeaxanthin, and Other Carotenoids and Age-Related Macular Degeneration During 2 Decades of Prospective Follow-up. JAMA Ophthalmol 2015;:1-10.Abstract

Importance: Despite strong biological plausibility, evidence from epidemiologic studies and clinical trials on the relations between intakes of lutein and zeaxanthin and age-related macular degeneration (AMD) has been inconsistent. The roles of other carotenoids are less thoroughly investigated. Objective: To investigate the associations between intakes of carotenoids and AMD. Design, Setting, and Participants: Prospective cohort study, with cohorts from the Nurses' Health Study and the Health Professionals Follow-up Study in the United States. A total of 63 443 women and 38 603 men were followed up, from 1984 until May 31, 2010, in the Nurses' Health Study and from 1986 until January 31, 2010, in the Health Professionals Follow-up Study. All participants were aged 50 years or older and were free of diagnosed AMD, diabetes mellitus, cardiovascular disease, and cancer at baseline. Main Outcomes and Measures: Predicted plasma carotenoid scores were computed directly from food intake, assessed by repeated food frequency questionnaires at baseline and follow-up, using validated regression models to account for bioavailability and reporting validity of different foods, and associations between predicted plasma carotenoid scores and AMD were determined. Results: We confirmed 1361 incident intermediate and 1118 advanced AMD cases (primarily neovascular AMD) with a visual acuity of 20/30 or worse by medical record review. Comparing extreme quintiles of predicted plasma lutein/zeaxanthin score, we found a risk reduction for advanced AMD of about 40% in both women and men (pooled relative risk comparing extreme quintiles = 0.59; 95% CI, 0.48-0.73; P for trend < .001). Predicted plasma carotenoid scores for other carotenoids, including β-cryptoxanthin, α-carotene, and β-carotene, were associated with a 25% to 35% lower risk of advanced AMD when comparing extreme quintiles. The relative risk comparing extreme quintiles for the predicted plasma total carotenoid index was 0.65 (95% CI, 0.53-0.80; P for trend < .001). We did not identify any associations of carotenoids, either as predicted plasma score or calculated intake, with intermediate AMD. Conclusions and Relevance: Higher intake of bioavailable lutein/zeaxanthin is associated with a long-term reduced risk of advanced AMD. Given that some other carotenoids are also associated with a lower risk, a public health strategy aimed at increasing dietary consumption of a wide variety of fruits and vegetables rich in carotenoids may reduce the incidence of advanced AMD.

Duminuco R, Noble JW, Goody J, Sharma M, Ksander BR, Roskelley CD, Cox ME, Mills J. Integrin-linked kinase regulates senescence in an Rb-dependent manner in cancer cell lines. Cell Cycle 2015;14(18):2924-37.Abstract

Anti-integrin-linked kinase (ILK) therapies result in aberrant mitosis including altered mitotic spindle organization, centrosome declustering and mitotic arrest. In contrast to cells that expressed the retinoblastoma tumor suppressor protein Rb, we have shown that in retinoblastoma cell lines that do not express Rb, anti-ILK therapies induced aberrant mitosis that led to the accumulation of temporarily viable multinucleated cells. The present work was undertaken to: 1) determine the ultimate fate of cells that had survived anti-ILK therapies and 2) determine whether or not Rb expression altered the outcome of these cells. Our data indicate that ILK, a chemotherapy drug target is expressed in both well-differentiated, Rb-negative and relatively undifferentiated, Rb-positive retinoblastoma tissue. We show that small molecule targeting of ILK in Rb-positive and Rb-deficient cancer cells results in increased centrosomal declustering, aberrant mitotic spindle formation and multinucleation. However, anti-ILK therapies in vitro have different outcomes in retinoblastoma and glioblastoma cell lines that depend on Rb expression. TUNEL labeling and propidium iodide FACS analysis indicate that Rb-positive cells exposed to anti-ILK therapies are more susceptible to apoptosis and senescence than their Rb-deficient counterparts wherein aberrant mitosis induced by anti-ILK therapies exhibit mitotic arrest instead. These studies are the first to show a role for ILK in chemotherapy-induced senescence in Rb-positive cancer lines. Taken together these results indicate that the oncosuppressive outcomes for anti-ILK therapies in vitro, depend on the expression of the tumor suppressor Rb, a known G1 checkpoint and senescence regulator.

Liu C-H, Sun Y, Li J, Gong Y, Tian KT, Evans LP, Morss PC, Fredrick TW, Saba NJ, Chen J. Endothelial microRNA-150 is an intrinsic suppressor of pathologic ocular neovascularization. Proc Natl Acad Sci U S A 2015;112(39):12163-8.Abstract

Pathologic ocular neovascularization commonly causes blindness. It is critical to identify the factors altered in pathologically proliferating versus normally quiescent vessels to develop effective targeted therapeutics. MicroRNAs regulate both physiological and pathological angiogenesis through modulating expression of gene targets at the posttranscriptional level. However, it is not completely understood if specific microRNAs are altered in pathologic ocular blood vessels, influencing vascular eye diseases. Here we investigated the potential role of a specific microRNA, miR-150, in regulating ocular neovascularization. We found that miR-150 was highly expressed in normal quiescent retinal blood vessels and significantly suppressed in pathologic neovessels in a mouse model of oxygen-induced proliferative retinopathy. MiR-150 substantially decreased endothelial cell function including cell proliferation, migration, and tubular formation and specifically suppressed the expression of multiple angiogenic regulators, CXCR4, DLL4, and FZD4, in endothelial cells. Intravitreal injection of miR-150 mimic significantly decreased pathologic retinal neovascularization in vivo in both wild-type and miR-150 knockout mice. Loss of miR-150 significantly promoted angiogenesis in aortic rings and choroidal explants ex vivo and laser-induced choroidal neovascularization in vivo. In conclusion, miR-150 is specifically enriched in quiescent normal vessels and functions as an endothelium-specific endogenous inhibitor of pathologic ocular neovascularization.

Rinaldi L, Vecchi T, Fantino M, Merabet LB, Cattaneo Z. The effect of hand movements on numerical bisection judgments in early blind and sighted individuals. Cortex 2015;71:76-84.Abstract

Recent evidence suggests that in representing numbers blind individuals might be affected differently by proprioceptive cues (e.g., hand positions, head turns) than are sighted individuals. In this study, we asked a group of early blind and sighted individuals to perform a numerical bisection task while executing hand movements in left or right peripersonal space and with either hand. We found that in bisecting ascending numerical intervals, the hemi-space in which the hand was moved (but not the moved hand itself) influenced the bisection bias similarly in both early blind and sighted participants. However, when numerical intervals were presented in descending order, the moved hand (and not the hemi-space in which it was moved) affected the bisection bias in all participants. Overall, our data show that the operation to be performed on the mental number line affects the activated spatial reference frame, regardless of participants' previous visual experience. In particular, both sighted and early blind individuals' representation of numerical magnitude is mainly rooted in world-centered coordinates when numerical information is given in canonical orientation (i.e., from small to large), whereas hand-centered coordinates become more relevant when the scanning of the mental number line proceeds in non-canonical direction.

Thanos S, Böhm MRR, Meyer Zu Hörste M, Schmidt P-F. Retinal damage induced by mirror-reflected light from a laser pointer. BMJ Case Rep 2015;2015Abstract

The safety of laser pointers is a major public health issue since class I and II laser pointers are available worldwide and used as toys by children despite several reports cautioning such use. Here we present the first case of retinal injury caused by the laser beam of a toy laser pointer operated by a school boy and directed via the rear-view mirror of a bus into the eye of the driver. This case emphasises the great importance of cautious and appropriate use of low-energy laser pointers. Laser pointers of any class should not be made available to children because they are unlikely to understand the risks of such lasers when using them in play.

Liu Y, Magro C, Loewenstein JI, Makar RS, Stowell CP, Dzik WH, Hochberg EP, Oaklander AL, Sobrin L. A Man with Paraneoplastic Retinopathy plus Small Fiber Polyneuropathy Associated with Waldenström Macroglobulinemia (Lymphoplasmacytic Lymphoma): Insights into Mechanisms. Ocul Immunol Inflamm 2015;23(5):405-9.Abstract
PURPOSE: To report a well-characterized Waldenström's macroglobulinemia (WM) case that provides insight into the mechanisms of two paraneoplastic complications -- cancer-associated retinopathy (CAR) and small fiber polyneuropathy (SFPN). METHODS: Retrospective medical chart review. RESULTS: A 58-year old man with WM developed vision loss and bilateral lower extremity pain. CAR was diagnosed by history, a depressed electroretinogram (ERG) and positive anti-retinal antibodies. SFPN diagnosis was based on abnormal autonomic nerve function testing and a distal-leg skin biopsy that demonstrated absent epidermal small-fiber innervation, IgM and complement deposition and microvasculopathy. Plasma exchange (PLEX) led to dramatic pain relief and subjective improvement in eye symptoms along with improvement of some ERG parameters. Repeat skin biopsy after treatment showed less microvascular abnormalities and decreased complement deposition. CONCLUSIONS: The concurrence of CAR and SFPN in this patient suggest that both were complications of WM and their common response to PLEX suggests co-mediation by humoral factors that accessed target antigens through IgM-triggered, complement-mediated vascular damage.
Hu K, Harris DL, Yamaguchi T, von Andrian UH, Hamrah P. A Dual Role for Corneal Dendritic Cells in Herpes Simplex Keratitis: Local Suppression of Corneal Damage and Promotion of Systemic Viral Dissemination. PLoS One 2015;10(9):e0137123.Abstract

The cornea is the shield to the foreign world and thus, a primary site for peripheral infections. However, transparency and vision are incompatible with inflammation and scarring that may result from infections. Thus, the cornea is required to perform a delicate balance between fighting infections and preserving vision. To date, little is known about the specific role of antigen-presenting cells in viral keratitis. In this study, utilizing an established murine model of primary acute herpes simplex virus (HSV)-1 keratitis, we demonstrate that primary HSV keratitis results in increased conventional dendritic cells (cDCs) and macrophages within 24 hours after infection. Local depletion of cDCs in CD11c-DTR mice by subconjuntival diphtheria toxin injections, led to increased viral proliferation, and influx of inflammatory cells, resulting in increased scarring and clinical keratitis. In addition, while HSV infection resulted in significant corneal nerve destruction, local depletion of cDCs resulted in a much more severe loss of corneal nerves. Further, local cDC depletion resulted in decreased corneal nerve infection, and subsequently decreased and delayed systemic viral transmission in the trigeminal ganglion and draining lymph node, resulting in decreased mortality of mice. In contrast, sham depletion or depletion of macrophages through local injection of clodronate liposomes had neither a significant impact on the cornea, nor an effect on systemic viral transmission. In conclusion, we demonstrate that corneal cDCs may play a primary role in local corneal defense during viral keratitis and preserve vision, at the cost of inducing systemic viral dissemination, leading to increased mortality.

Pal-Ghosh S, Pajoohesh-Ganji A, Tadvalkar G, Kyne BM, Guo X, Zieske JD, Stepp MA. Topical Mitomycin-C enhances subbasal nerve regeneration and reduces erosion frequency in the debridement wounded mouse cornea. Exp Eye Res 2015;Abstract

Corneal epithelial basement membrane dystrophies and superficial injuries caused by scratches can lead to recurrent corneal erosion syndrome (RCES). Patients and animals with reduced corneal sensory nerve innervation can also develop recurrent erosions. Multiple wild-type mouse strains will spontaneously develop recurrent corneal erosions after single 1.5 mm debridement wounds. Here we show that this wound is accompanied by an increase in corneal epithelial cell proliferation after wound closure but without a commensurate increase in corneal epithelial thickness. We investigated whether excess corneal epithelial cell proliferation contributes to erosion formation. We found that topical application of Mitomycin C (MMC), a drug used clinically to improve healing after glaucoma and refractive surgery, reduces erosion frequency, enhances subbasal axon density to levels seen in unwounded corneas, and prevents excess epithelial cell proliferation after debridement wounding. These results suggest that topically applied MMC, which successfully reduces corneal haze and scarring after PRK, may also function to enhance subbasal nerve regeneration and epithelial adhesion when used to treat RCES.

Silva PS, Dela Cruz AJ, Ledesma MG, van Hemert J, Radwan A, Cavallerano JD, Aiello LM, Sun JK, Aiello LP. Diabetic Retinopathy Severity and Peripheral Lesions Are Associated with Nonperfusion on Ultrawide Field Angiography. Ophthalmology 2015;122(12):2465-72.Abstract

PURPOSE: To assess whether the presence of peripheral nonperfusion on ultrawide field (UWF) fluorescein angiography (FA) is associated with diabetic retinopathy (DR) severity and the presence of predominantly peripheral lesions (PPLs). DESIGN: Single-site, cross-sectional, retrospective study. PARTICIPANTS: Sixty-eight eyes of 37 diabetic subjects with or without DR and no history of prior panretinal laser photocoagulation. METHODS: Both 200° UWF images and UWF FA images were acquired at the same visit. Early Treatment Diabetic Retinopathy Study (ETDRS) templates were overlaid digitally based on disc and macula location onto stereographically projected UWF images. Images were evaluated for the presence of PPLs, defined as more than 50% of the graded lesion located outside the ETDRS field in each of the 5 extended fields. The UWF-FA images were evaluated by 2 masked, independent graders for extent of retinal nonperfusion area (NPA) and nonperfusion index (NPI; nonperfused/total gradable area). MAIN OUTCOME MEASURES: Association of NPA and NPI with DR severity and presence of PPLs. RESULTS: Distribution of DR severity was as follows: no DR, 8.8% eyes; mild nonproliferative DR (NPDR), 17.6%; moderate NPDR, 32.4%; severe NPDR, 17.6%; proliferative DR (PDR), 19.1%; and high-risk PDR, 4.4%; with PPL present in 61.8%. There was strong intragrader (r = 0.95) and intergrader (r = 0.86) agreement for NPA. Presence of PPLs was associated with increased NPA (191.8 mm(2) vs. 306.1 mm(2); P = 0.0019) and NPI (0.25 vs. 0.43; P = 0.0003). These relationships remained significant after adjusting for DR severity and diabetes duration. In eyes without PDR (n = 52), increasing NPA and NPI was associated with worsening DR (NPA, P = 0.001; NPI, P = 0.0003). NPA and NPI were not associated with clinically significant macular edema (NPA, P = 0.99; NPI, P = 0.67), nor correlated with visual acuity (NPA, r = 0.14, P = 0.23; NPI, r = 0.24, P = 0.05). CONCLUSIONS: Following a standardized protocol, the evaluation of UWF FA for NPA and NPI is reproducible. Both parameters are correlated highly with the presence of PPLs and DR severity. Given that the presence and extent of PPLs have been associated with increased risks of DR progression, the clinical identification of PPLs may reflect closely the extent of nonperfusion and ischemia, thus accounting for the increased risk of progression.

Veldman PB, Dye PK, Holiman JD, Mayko ZM, Sáles CS, Straiko MD, Stoeger CG, Terry MA. Stamping an S on DMEK Donor Tissue to Prevent Upside-Down Grafts: Laboratory Validation and Detailed Preparation Technique Description. Cornea 2015;34(9):1175-8.Abstract

PURPOSE: To report endothelial cell loss (ECL) caused by a novel S-stamp preparation technique for Descemet membrane endothelial keratoplasty (DMEK). METHODS: Six cadaveric human corneas were prepared for DMEK transplantation using a single standardized technique, including the application of a dry ink gentian violet S-stamp to the stromal side of Descemet membrane. Endothelial cell death was evaluated and quantified using computerized analysis of vital dye staining. RESULTS: ECL caused by the S-stamp was 0.6% (range 0.1%-1.0%), which comprised less than one-tenth of the total ECL caused by our preparation of the DMEK graft from the start to finish, including recovery, prestripping, S-stamping, and trephination (13.7% total ECL, range 9.9%-17.6%). CONCLUSIONS: Our novel S-stamp donor tissue preparation technique is intuitive to learn and holds the promise of preventing iatrogenic primary graft failure due to upside-down grafts without causing unacceptable increases in ECL.

MacIntosh PW, Jakobiec FA, Stagner AM, Gilani S, Fay A. High grade neuroendocrine neoplasm of the antrum and orbit. Surv Ophthalmol 2015;60(5):486-94.Abstract

Neuroendocrine malignancies-tumors characterized by the production of dense-core secretory granules-are most often encountered in the lungs and can also be found in extrapulmonary sites. Our patient had a primary neuroendocrine tumor of the antrum with an elusive cell of origin that secondarily invaded the inferior orbit. In the sinuses, neuroendocrine tumors may be confused with infectious sinusitis or squamous cell carcinoma. There are no known pathognomonic clinical or radiographic signs to distinguish these tumors from other conditions. Diagnosis depends on a biopsy with histopathologic and immunohistochemical analysis to identify biomarkers such as synaptophysin, chromogranin, CD56 and neuron specific enolase. Our patient's tumor defied precise immunohistochemical characterization because of its primitive character and erratic biomarker expression. The diagnosis oscillated between a neuroendocrine carcinoma and an ectopic esthesioneuroblastoma grade IV-hence the use of the more generic nosologic category of neuroendocrine neoplasm without specifying a neuronal or epithelial origin. Data to guide management are limited, particularly in the ophthalmic literature, and derive from experience with tumors of the sinonasal compartments. In the present case of a sino-orbital high grade neuroendocrine neoplasm, regional lymph node metastases developed shortly after presentation. The tumor has responded well to chemotherapy and radiation, but recurrence is often encountered within 2 years in this class of neoplasms.

Dib B, Lin H, Maidana DE, Tian B, Miller JB, Bouzika P, Miller JW, Vavvas DG. Mitochondrial DNA has a pro-inflammatory role in AMD. Biochim Biophys Acta 2015;1853(11 Pt A):2897-906.Abstract

Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in the elderly of industrialized nations, and there is increasing evidence to support a role for chronic inflammation in its pathogenesis. Mitochondrial DNA (mtDNA) has been recently reported to be pro-inflammatory in various diseases such as Alzheimer's and heart failure. Here, we report that intracellular mtDNA induces ARPE-19 cells to secrete inflammatory cytokines IL-6 and IL-8, which have been consistently associated with AMD onset and progression. The induction was dependent on the size of mtDNA, but not on specific sequence. Oxidative stress plays a major role in the development of AMD, and our findings indicate that mtDNA induces IL-6 and IL-8 more potently when oxidized. Cytokine induction was mediated by STING (Stimulator of Interferon Genes) and NF-κB as evidenced by abrogation of the cytokine response with the use of specific inhibitors (siRNA and BAY 11-7082, respectively). Finally, mtDNA primed the NLRP3 inflammasome. This study contributes to our understanding of the potential pro-inflammatory role of mtDNA in the pathogenesis of AMD.

Pages