Cytomegalovirus immunoglobulin therapy for CMV retinitis post hematopoietic stem cell transplantation.

PURPOSE: To report a case of cytomegalovirus (CMV) retinitis complicated with ganciclovir-related myelosuppression, which was successfully managed with intravenous (IV) ganciclovir and CMV immunoglobulin (CMVIG) therapy. METHODS: Observational case report. RESULTS: A 51-year-old male with follicular type non-Hodgkin lymphoma post hematopoietic stem cell transplantation (HSCT) developed vision-threatening retinitis. polymerase chain reaction (PCR) of the aqueous humour showed positive for CMV. Despite myelosuppression occurred during IV ganciclovir therapy, the retinitis resolved and intraocular CMV viral load significantly improved after CMVIG therapy. CONCLUSION: Combined IV ganciclovir treatment and CMVIG therapy can significantly improve visual outcome and reduce intraocular CMV viral load in vision-threatening CMV retinitis.

Polycythemia-Related Proliferative Ischemic Retinopathy Managed with Smoking Cessation: A Case Report.

Ischemic retinopathy characterized by neovascularization could result from several diseases such as proliferative diabetic retinopathy, hypertensive retinopathy, and retinal vein occlusion. However, ocular ischemic conditions caused by polycythemia have rarely been described. We report the first case of polycythemia-related proliferative ischemic retinopathy in a 41-year-old male heavy smoker who had ocular ischemic condition due to secondary polycythemia. He had sudden loss of vision in his right eye vision with vitreous hemorrhage and a tortuous retinal artery. Tracing back to his history, he was a heavy smoker with more than one pack of cigarettes per day for more than 30 years. Laboratory data revealed elevated levels of hemoglobin (17.7 g/dL) and hematocrit (51.6%) without other abnormal findings. We performed retinal photocoagulation on the neovascular areas and the fibrous membrane. Additionally, the patient was advised to quit smoking. Owing to adherence to this treatment, the patient's vision gradually recovered. Although rare, polycythemia can cause retinal ischemic events and should be considered as a sight-threatening disease. Photocoagulation is effective on the regression of the neovascular lesion. Most importantly, changes in lifestyle together with smoking cessation are effective in managing secondary polycythemia. In conclusion, prevention and cessation of tobacco consumption helps improve vision health.

Long-Term Follow-Up of Refractory Large Macular Hole with Autologous Neurosensory Retinal Free Flap Transplantation.

Purpose: To evaluate the long-term anatomic and functional outcomes of autologous neurosensory retinal free flap transplantation (ART) for patients with refractory large macular hole (MH). Design: Retrospective interventional case series. Methods: We reviewed 9 patients who underwent ART for their refractory large MH. In this extended follow-up study, postoperative assessment including spectral-domain optical coherence tomography and best-corrected visual acuity (BCVA) were recorded at 12, 15, 18, 21, and 24 months after surgery. Results: The macular hole of all patients appeared successfully closed during the whole follow-up period. The mean logMAR BCVA improved from 1.61 ± 0.44 (preoperative) to 0.72 ± 0.30 (12 months after surgery) (p < 0.001). Thereafter, the mean BCVA remained stable at each follow-up. At the mean 16.0 ± 0.8 months postoperatively, inner retinal cystic changes were observed in 4 eyes (44.4%), but these did not significantly affect vision. Conclusion: ART is a good alternative technique for closing large refractory macular holes. Although inner retinal cystic changes were observed in 4 eyes (44.4%), this phenomenon did not significantly affect visual acuity. It provides long-term good anatomical and functional results, especially in cases where insufficient ILM or lens capsule are left.

Dexamethasone Intravitreal Implant (Ozurdex) for Long-Term Macular Edema after Epiretinal Membrane Peeling Surgery.

PURPOSE: To investigate the functional and anatomical outcome of the 0.7 mg dexamethasone (Ozurdex) intravitreal implant (IVD) in eyes with long-term macular edema after macular epiretinal membrane removal. METHODS: We enrolled 40 eyes with persistent macular edema at least 12 months after epiretinal membrane removal. Twenty eyes in the IVD group received IVD and the other 20 eyes were in the control group. The main outcome measures were change in best-corrected visual acuity (BCVA) and central foveal thickness (CFT). RESULTS: For eyes in the IVD group, the mean BCVA improved by 3.45 lines to 0.47 logMAR one month after IVD. However, the mean BCVA improved by only 0.14 lines to 0.74 logMAR at the same time in eyes in the control group. Six months later, the mean BCVA improved to 0.31 and 0.74 logMAR in the IVD and control groups, respectively. In the IVD group, the mean CFT decreased rapidly by 116.8 µm to 333.9 µm one month after IVD. Thereafter the CFT decreased at a slower pace. In the control group, the CFT remained static during the follow-up period. However, in the IVD group, 6 months after IVD, the CFT seemed to have a tendency to increase. CONCLUSIONS: Single IVD could significantly decrease macular edema and improve visual outcome for eyes with persistent long-term macular edema after macular ERM removal and the effect can be sustained as long as 6 months after the initial injection. However, in order to maintain the visual and anatomical outcome, repeat IVD might be considered if macular edema recurs.

High mobility group B1 up-regulates angiogenic and fibrogenic factors in human retinal pigment epithelial ARPE-19 cells.

Hypoxia-induced retinal neovascularization plays a central role in the pathogenesis of diabetic retinopathy. This study aimed to investigate whether hypoxia leads to the release of nuclear high mobility group box 1 (HMGB1) peptides from cultured retinal pigment epithelial ARPE-19 cells, to determine the effect of HMGB1 on angiogenic cytokine production and elucidate the involved signaling pathways. A chemical hypoxia mimetic agent, cobalt chloride, induced SIRT1 downregulation, HMGB1 nucleocytoplasmic relocation and extracellular release from ARPE-19 cells, implicating its autocrine function. Resveratrol treatment significantly reduced secretion of HMGB1 from ARPE-19 cells exposed to hypoxia. Cell proliferation and cell cycle analyses demonstrated that exogenous HMGB1 caused significant growth suppression and G1 cell cycle arrest in ARPE-19 cells. Morphological observations showed that HMGB1 enhanced adhesion, but suppressed migration of ARPE-19 cells. More intriguingly, HMGB1 up-regulated expression of angiofibrogenic factors in ARPE-19 cells, including VEGF, bFGF, TGF-ß2, and CTGF. Signal profiling characterization indicated that HMGB1 triggered hyperphosphorylation of Akt, p38 MAPK, and NF-κB, but not that of ERK, JNK, and Smad2, whereas inhibition of PI3K, MAPK, or NF-κB significantly attenuated the HMGB1-driven cytokine overproduction in ARPE-19 cells. Functional neutralization with anti-TLR4 and -RAGE antibodies confirmed that both receptors were involved in the cytokine overproduction. In conclusion, chemically-mimicked hypoxia induced nucleocytoplasmic relocation and release of HMGB1 peptides, which in turn up-regulated the production of angiofibrogenic factors in RPE cells, thereby contributing to the pathogenesis of hypoxia-associated diabetic retinopathies. Conversely, blockades of intraocular HMGB1 bioavailability or signal activation may prevent angiofibrogenesis in development of diabetic retinopathy.

All-trans retinoic acid suppresses the adhering ability of ARPE-19 cells via mitogen-activated protein kinase and focal adhesion kinase.

This study investigated the signaling mechanism underlying the anti-adhesive effect of all-trans retinoic acid (ATRA) on retinal pigment epithelial ARPE-19 cells. Adhesion kinetics with or without ATRA treatment were profiled by adhesion assay. Surface coating with type IV collagen, fibronectin, laminin, but not type I collagen, significantly enhanced adhesion and spreading of ARPE-19 cells, while ATRA at subtoxic doses (ranging from 10-7 to 10-6 M) profoundly suppressed the extracellular matrix-enhanced adhesion ability. Cell attachment on FN activated PI3K/Akt and MAPK cascades, whereas ATRA pretreatment blunted the early phosphorylation of Akt and MAPK signaling mediators including p38 MAPK, JNK1/2, and ERK1/2. Mechanistically, signaling blockade with selective kinase inhibitors demonstrated that all MAPK pathways were involved in the anti-adhesive effect of ATRA, whereas the PI3K inhibitor treatment significantly potentiated the ATRA-suppressed RPE cell adhesion. Moreover, ATRA treatment did not affect intracellular F-actin distribution, but remarkably reduced focal adhesion kinase (FAK) expression and its nuclear localization during ARPE-19 cell attachment. In conclusion, ATRA suppresses the adhering ability of ARPE-19 cells at least in part through MAPK and FAK pathways. Signaling blockade with PI3K inhibitor could be regarded as an alternative modality for treating proliferative vitreoretinopathy.

Methylglyoxal, a reactive glucose metabolite, enhances autophagy flux and suppresses proliferation of human retinal pigment epithelial ARPE-19 cells.

Methylglyoxal (MGO), a glycolytic metabolite, induces oxidative injury and apoptotic cell death that play a pathogenetic role in age-related macular degeneration (AMD). This study examined the impact of MGO on cell proliferation and autophagy flux in retinal pigment epithelium (RPE) ARPE-19 cells and elucidated the underlying mechanism. Short-term MGO exposure suppressed cell proliferation without induction of apoptotic cell death, increased production of reactive oxygen species, and potentiated H2O2-exhibited cytotoxicity in ARPE-19 cells. Conversely, pretreatment with N-acetylcysteine, a ROS scavenger, and aminoguanidine, an MGO blocker, prevented MGO-induced growth retardation. MGO significantly enhanced autophagy flux and increased intracellular accumulation of autophagosomes, which was functionally confirmed by addition of autophagy enhancer or inhibitors. Signaling kinetic observation indicated that MGO remarkably triggered phosphorylation of Akt, ERK1/2, p38 MAPK, and JNK1/2. Blockade of kinase activity demonstrated that the hyperphosphorylation of Akt, ERK1/2, JNK, and p38 MAPK were all involved in the MGO-enhanced autophagy and growth-arresting effect in ARPE-19 cells. Moreover, pretreatment with autophagic flux inhibitors including 3-methyladenine, bafilomycin A, and chloroquine effectively ameliorated MGO- but not H2O2-mediated ARPE-19 cytotoxicity. In conclusion, modulation of autophagy flux activity by using autophagic or kinase inhibitors may be an applicable modality to treat AMD.

Correlation Between the Dynamic Postoperative Visual Outcome and the Restoration of Foveal Microstructures After Macular Hole Surgery.

PURPOSE: To analyze the long-term dynamic healing process of outer retinal changes for 1 year in patients who underwent a standard vitrectomy procedure for idiopathic macular hole (MH) repair. DESIGN: Retrospective, consecutive, observational case series. METHODS: Data were collected on 60 eyes of 56 patients (30 women, 26 men) that underwent successful pars plana vitrectomy (PPV) and internal limiting membrane (ILM) peeling for idiopathic MH from January 2011 to December 2012. The age distribution ranged from 56 to 85 years (mean: 64 years). Forty eyes underwent combined phacoemulsification, PPV, ILM peeling, and intraocular lens implantation; 20 preoperative pseudophakic eyes underwent PPV and ILM peeling only. The main outcome measures included logMAR best-corrected visual acuity (BCVA) and macular microstructures determined by spectral-domain optical coherence tomography performed pre- and postoperatively during follow-up visits at 1, 3, 6, 9, and 12 months. RESULTS: One month after surgery, 24 eyes (40%) showed normal external limiting membrane (ELM), 36 eyes (60%) showed normal ELM at 3 months, and 54 eyes (90%) showed normal ELM 12 months after surgery. Six eyes (10%) revealed a continuous ellipsoid zone (EZ) at 1 month, 18 eyes (30%) at 3 months, and 48 eyes (80%) at 12 months postoperatively. There were no eyes with a disrupted ELM in the presence of an intact EZ line. The eyes with intact ELM and/or intact EZ line showed better BCVA than eyes with defects in ELM or EZ line. On the contrary, glial cell presentation is significantly associated with worse postoperative BCVA. However, the presence of foveal cystoid change is not significantly associated with postoperative BCVA. CONCLUSIONS: The ELM and EZ line at the fovea recovered and the presence of glial cells and cystoid space resolved gradually after surgery. The postoperative visual acuity was correlated with resolved glial cells and a restored ELM and EZ line.

Pharmacological implications from the adhesion-induced signaling profiles in cultured human retinal pigment epithelial cells.

Extracellular matrix (ECM) plays an active and complex role in regulating cellular behaviors, including proliferation and adhesion. This study aimed at delineating the adhesion-induced signaling profiles in cultured human retinal pigment epithelium (RPE) cells and investigating the antiadhesion effect of antiproliferative drugs in this context. RPE R-50 cells grown on various ECM molecules, such as type I and IV collagens, fibronectin, and laminin, were used for adhesion assay and for examining the phosphorylation profiles of signaling mediators including Akt, extracellular signal-regulated kinase (ERK) 1/2, and integrin-linked kinase (ILK) using Western blotting. The cells receiving antiproliferative drug treatment at subtoxic doses were used to evaluate their antiadhesive and suppressive effects on kinase activities. ECM coating enhanced adhesion and spreading of RPE cells significantly. The cellular attachment onto ECM-coated surfaces differentially induced Akt, ERK1/2, and ILK phosphorylation, and concomitantly increased p53 phosphorylation and cyclin D1 expression, but decreased Bcl-2/Bax ratios. Treatment with antiproliferative agents, including 5-fluorouracil, mitomycin C, and daunomycin, at subtoxic doses suppressed the ability of RPE cells to adhere to ECM substratum significantly. This suppression was in part mediated through reduction of integrin ß1 and ß3 expressions and interfering Akt-ILK signaling activity. Mechanistically, blockade of PI3K/Akt signaling resulted in the suppressed adhesion of RPE cells to ECM. These findings support the hypothesis that, in addition to their antimitogenic effect, antiproliferative agents also exhibit suppressive effect on the adhesiveness of cultured RPE cells. Moreover, inhibitors of the PI3K/Akt signaling mediator can potentially be used as therapeutic agents for proliferative vitreoretinopathy.

Pleiotropic role of atorvastatin in regulation of human retinal pigment epithelial cell behaviors in vitro.

Statins, inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, possess pleiotropic effects that have been extended to modulation of various cellular behaviors. This study aimed at examining whether atorvastatin (AVN) modulates cell growth, adhesion, migration, and contraction of cultured human retinal pigment epithelium (RPE) cells. The in vitro effects of AVN on human RPE cells was analyzed in terms of cell proliferation, cell cycle, cell adhesion, migration, and contraction assays. The modulatory effect of AVN on TGF-ß2-triggered signaling was determined by Western blotting detection. AVN at submicromolar dose exhibited no prominent morphological alteration and cytotoxicity, whereas it elicited cytostatic effect at concentrations higher than 1 µM. Cell cycle analysis showed that AVN induced growth arrest in both G1 and G2/M phases. AVN at 1 µM or higher concentrations significantly suppressed RPE cell adhesion. Cell migration and 3D collagen contraction assays showed that AVN significantly suppressed RPE cell migration and contractility, respectively. Mechanistically, AVN treatment transiently up-regulated phosphorylation of Akt, ERK1/2, and p38 MAPK, whereas down-regulated that of JNK1. Intriguingly, AVN pretreatment prominently attenuated the TGF-ß(2)-mediated non-Smad signaling, including Akt, ERK1/2, p38 MAPK, and JNK1 phosphorylation. Besides, it directly reduced constitutive level of myosin regulatory light chain peptide MYL9 and mitigated the TGF-ß(2)-induced phosphorylation of myosin phosphatase-targeting subunit 1, MYPT1. These in vitro findings strongly suggest that AVN possesses pleiotropic function on RPE cells, including anti-proliferation, anti-adhesion, anti-migration as well as anti-contraction. In conclusion, AVN treatment may be considered a useful therapy for proliferative vitreoretinal diseases.

Geldanamycin and its analog induce cytotoxicity in cultured human retinal pigment epithelial cells.

Geldanamycin (GA), a benzoquinone ansamycin, was originally isolated as a natural product with anti-fungal activity. GA and its analogs, including 17-allylamino-demethoxy geldanamycin (17-AAG), are also known to block the function of a molecular chaperone, heat shock protein 90 (Hsp90). In light of their anti-tumor properties through direct cytotoxicity and anti-angiogenicity, GA has been previously demonstrated to suppress hypoxia-induced VEGF production in retinal pigment epithelium (RPE) cells, implicating its applicability in treating intraocular neovascularization. This study aimed at investigating the effectiveness of Hsp90 inhibitor treatment in suppressing proliferation of cultured human RPE cells and elucidating its underlying mechanism. Cultured RPE cells were treated with GA or 17-AAG and subjected for cell proliferation assay and cell cycle analysis. Expression of apoptotic regulators and survival signaling activity were monitored by Western blotting. The results showed that both GA and 17-AAG significantly inhibited RPE cell proliferation at micromolar levels. Treatment with GA and 17-AAG led to growth arrests in G1 and S phases, increased sub-G1 hypodipoid cell population, induced apoptotic cell death, and upregulated P53 and P21 expression, although the drug-induced Bcl-2 upregulation cannot prevent cell death. Additionally, GA and 17-AAG significantly suppressed constitutive contents of phosphorylated ERK1/2 and total Akt proteins, and completely abrogated wortmannin-sensitized Akt phosphorylation. In conclusion, GA and 17-AAG inhibit RPE cell proliferation and induce cytotoxicity, possibly through downregulating Akt- and ERK1/2-mediated signaling activities. They might potentially constitute a therapeutic agent for ocular disorders with RPE over proliferation, such as proliferative vitreoretinopathy.

Associations between arsenic in drinking water and pterygium in southwestern Taiwan.

BACKGROUND: Pterygium is a fibrovascular growth of the bulbar conjunctiva and underlying subconjunctival tissue that may cause blindness. The mechanism of pterygium formation is not yet fully understood, but pterygium has some tumorlike features. OBJECTIVES: The objective of this study was to evaluate the association between arsenic exposure through drinking water and the occurrence of pterygium in southwestern Taiwan. METHODS: We recruited participants > 40 years of age from three villages in the arseniasis-endemic area in southwestern Taiwan (exposure villages) and four neighboring nonendemic villages (comparison villages). Each participant received an eye examination and a questionnaire interview. Photographs taken of both eyes were later graded by an ophthalmologist to determine pterygium status. RESULTS: We included 223 participants from the exposure villages and 160 from the comparison villages. The prevalence of pterygium was higher in the exposure villages across all age groups in both sexes and increased with cumulative arsenic exposure. We found a significant association between cumulative arsenic exposure and the prevalence of pterygium. After adjusting for age, sex, working under sunlight, and working in sandy environments, we found that cumulative arsenic exposure of 0.1-15.0 mg/L-year and > or = 15.1 mg/L-year were associated with increased risks of developing pterygium. The adjusted odds ratios were 2.04 [95% confidence interval (CI), 1.04-3.99] and 2.88 (95% CI, 1.42-5.83), respectively. CONCLUSIONS: Chronic exposure to arsenic in drinking water was related to the occurrence of pterygium, and the association was still observed after adjusting for exposures to sunlight and sandy environments.