Effects of oxysterols on cell viability, inflammatory cytokines, VEGF, and reactive oxygen species production on human retinal cells: cytoprotective effects and prevention of VEGF secretion by resveratrol.

BACKGROUND AND AIMS: Oxysterols are assumed to play important roles in age-related macular degeneration, a major cause of blindness. So we characterized the cytotoxic, oxidative, inflammatory, and angiogenic activities of oxysterols (7ß-hydroxycholesterol (7ß-OH), 7-ketocholesterol (7KC), 25-hydroxycholesterol (25-OH)) in human retinal ARPE-19 cells, and evaluated the protective effects of resveratrol (Rsv: 1 µM), a polyphenol from red wine. METHODS: ARPE-19 cells were treated with 7ß-OH, 7KC, or 25-OH (5-40 µg/mL; 24-48 h) without or with Rsv. Cell viability was determined using trypan blue and the MTT assay. Cell death was characterized by electron microscopy and in situ detection of activated caspases with fluorochrome-labeled inhibitors of caspases. Reactive oxygen species (ROS) production was measured with hydroethidine. ELISA methods and a cytometric bead assay were used to quantify cytokines involved in inflammation (IL-8, IL-1ß, IL-6, IL-10, IL-12p70, TNF-α, MCP-1) and VEGF. RESULTS: 7ß-OH and 7KC triggered a caspase-independent cell death process associated with the presence of multilamellar cytoplasmic structures evocating phospholipidosis, increased ROS production, and IL-8 secretion. 7ß-OH enhanced VEGF secretion. No cytotoxic effects were identified with 25-OH, which highly stimulated ROS production, MCP-1, and VEGF secretion. With oxysterols, no IL-10, TNF-α, and IL-12p70 secretion were detected. 25-OH induced IL-8 secretion through the MEK/ERK½ signaling pathway, and Rsv showed cytoprotective activities and inhibited VEGF secretion. CONCLUSION: 7ß-OH, 7KC, and 25-OH have cytotoxic, oxidative, inflammatory, and/or angiogenic activities on ARPE-19 cells. As Rsv has some protective effects against oxysterol-induced cell death and VEGF secretion it could be valuable in ARMD treatment.

Measurement of inflammatory cytokines by multicytokine assay in tears of patients with glaucoma topically treated with chronic drugs.

AIM: To investigate the ocular surface inflammatory response to chronic topical treatments in patients with glaucoma by measuring the cytokine level in tears using multiplex bead analysis. METHODS: Tear samples were collected from 21 patients with glaucoma and 12 healthy volunteers. Tears were analysed for the presence of 17 cytokines: interleukin (IL)1beta, IL2, IL4, IL5, IL6, IL7, IL8, IL10, IL12, IL13, IL17, granulocyte-colony stimulating factor, granulocyte-macrophage stimulating factor, interferon (INF)gamma, monocyte chemotactic protein (MCP)1, macrophage inflammatory protein 1beta and tumour necrosis factor (TNF)alpha. The cytokines in each sample of tears were measured using multiplex bead analysis with microspheres as solid support for immunoassays. RESULTS: In the tears of treated patients, proinflammatory cytokines (IL1beta, IL6, IL12, TNFalpha) were significantly increased compared with controls. T helper (Th)1 (INFgamma, IL2) and Th2 (IL5, IL10, IL4) type cytokines were also significantly higher (p<0.05); however, the most marked increase was observed with Th1 cytokines. The expression of chemokine IL8 and MCP1 was also increased in the treated group. CONCLUSION: This study shows that pro-inflammatory cytokine secretion by conjunctival cells is increased in response to topical treatments for glaucoma. The characterisation of cytokines in tears was previously limited by the small volume attainable, a limitation that has been overcome by multiplex analysis.

[Efficacy of three intravitreal injections of bevacizumab in the treatment of exudative age-related macular degeneration]. / Étude préliminaire sur l'efficacité de trois injections intravitréennes de bevacizumab dans le traitement de la dégénérescence maculaire liée à l'âge exsudative.

INTRODUCTION: To evaluate intravitreal bevacizumab therapy for choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD). MATERIAL AND METHODS: A retrospective review between June 2006 and May 2008 of patients with CNV secondary to AMD was conducted. All patients were treated with intravitreal injection of bevacizumab (1.25mg) once a month during a 3-month-period. The mean evaluation criteria were the best-corrected visual acuity (BCVA) logMar testing before and one month after the third injection. All eyes underwent an angiography and an optical coherence tomography before injections to define the activity and the type of CNV and then to evaluate the persistence of leakage (macular edema, subretinal fluid, and pigment epithelial detachment) after treatment. Then treatments were left to the investigator's discretion during the following six months. RESULTS: Seventy-one eyes of 66 patients were enrolled. There were 65% occult CNV, 20% classic CNV, and 15% combined. A significant improvement in BCVA was observed, from 0.88±0.57 to 0.77±0.60 (p=0.001), one month after the third injection. At this time, 57.7% of the eyes required a reinjection because of leakage persistence. A concomitant treatment with intravitreal triamcinolone injection and/or photodynamic therapy was necessary for 8% of nonresponder eyes. Six months after initial treatment, a complete resolution of exudative signs was not obtained for 33.8% of eyes. The average number of injections was 3.85±0.96 during the 9-month follow-up. BCVA stability was observed at 4, 6 and 9-month follow-ups (F(71.2)=1.54; p=0.46). Three complications occurred: one endophthalmitis, one retinal tear, and one vitreous hemorrhage secondary to a macular hemorrhage. DISCUSSION: Mean BCVA significantly improved at one month after three consecutive monthly intravitreal injections of bevacizumab. However, most eyes required a reinjection. CONCLUSION: In spite of improvement in BCVA, leakage of the CNV persisted in most eyes after three monthly intravitreal injections of bevacizumab. Then retreatment and sometimes concomitant treatment was necessary to obtain complete resolution of exudative signs and BCVA stability.

How to improve screening for diabetic retinopathy: the Burgundy experience.

OBJECTIVES: The aim of this study was to evaluate the impact of a mobile diabetic retinopathy (DR) screening programme on the overall ophthalmological follow-up of diabetics in Burgundy. METHODS: The primary objective was to compare the rate of eye examinations, according to the information personnalisée aux professionnels de santé (IPPS; personalized information sent to health professionals) database, in diabetics before and after the screening campaign in selected zones. The secondary objectives were to compare the rate of eye examinations in diabetics before and after the screening programme in two different situations: with a mobile site; and with general practitioners (GPs) who teach in medical school. The impact of the different kinds of information on improving DR screening participation was also assessed. RESULTS: The overall rate of ophthalmological visits did not change significantly before vs after the screening campaign (42.2% vs 41.8%; P=0.73), nor did the rate of ophthalmological visits in screened areas (44% vs 43%; P=0.58), compared with non-screened areas (41% vs 41%; P=0.99) and the sectors with GPs as teachers (47% vs 49%). Patients referred to the screening programme were mainly informed of the screening by flyers provided by the National Health System. CONCLUSION: The DR screening campaign represents a major improvement in diabetic management, as around 80% of the screened patients with DR consulted an ophthalmologist after the screening campaign. However, the overall rate of diabetics having the recommended annual ophthalmological visit in the region of Burgundy remained unchanged.

Side effects of oxysterols: cytotoxicity, oxidation, inflammation, and phospholipidosis.

Oxysterols are 27-carbon atom molecules resulting from autoxidation or enzymatic oxidation of cholesterol. They are present in numerous foodstuffs and have been demonstrated to be present at increased levels in the plasma of patients with cardiovascular diseases and in atherosclerotic lesions. Thus, their role in lipid disorders is widely suspected, and they might also be involved in important degenerative diseases such as Alzheimer's disease, osteoporosis, and age-related macular degeneration. Since atherosclerosis is associated with the presence of apoptotic cells and with oxidative and inflammatory processes, the ability of some oxysterols, especially 7-ketocholesterol and 7beta-hydroxycholesterol, to trigger cell death, activate inflammation, and modulate lipid homeostasis is being extensively studied, especially in vitro. Thus, since there are a number of essential considerations regarding the physiological/pathophysiological functions and activities of the different oxysterols, it is important to determine their biological activities and identify their signaling pathways, when they are used either alone or as mixtures. Oxysterols may have cytotoxic, oxidative, and/or inflammatory effects, or none whatsoever. Moreover, a substantial accumulation of polar lipids in cytoplasmic multilamellar structures has been observed with cytotoxic oxysterols, suggesting that cytotoxic oxysterols are potent inducers of phospholipidosis. This basic knowledge about oxysterols contributes to a better understanding of the associated pathologies and may lead to new treatments and new drugs. Since oxysterols have a number of biological activities, and as oxysterol-induced cell death is assumed to take part in degenerative pathologies, the present review will focus on the cytotoxic activities of these compounds, the corresponding cell death signaling pathways, and associated events (oxidation, inflammation, and phospholipidosis).

[Vitreoretinal outpatient surgery: clinical and financial considerations]. / Chirurgie rétino-vitréenne en ambulatoire: une expérience enrichissante, mais coûteuse...

INTRODUCTION: Vitreoretinal surgery has benefited from great advances opening the opportunity for outpatient management. METHODS: We report on the 6-month experience of outpatient surgery for vitreoretinal diseases. RESULTS: From November 2007 to April 2008, 270 patients benefited from a vitreoretinal surgery, with 173 retinal detachments, 63 epiretinal membranes, and 34 other procedures. Only 8.5% (n=23) of the patients had to stay at the hospital one or two nights. The main reasons were the distance from the hospital and surgery on a single-eye patient. The questionnaire given after the surgery showed that almost all the patients were satisfied with the outpatient setting. In contrast, the financial results showed a loss of income of around 400,000 euros due to the low level of payment of outpatient surgery in France by the national health insurance system. DISCUSSION: Vitreoretinal surgery can be achieved in outpatient surgery with an improvement in the information given to the patients and the overall organization of the hospitalization. However, the current income provided with vitreoretinal outpatient surgery is highly disadvantageous in France, preventing this method from being generalized.

[Analogies between atherosclerosis and age-related maculopathy: expected roles of oxysterols]. / Analogies entre processus athéromateux et dégénérescence maculaire liée à l'âge: rôles présumés des oxystérols.

The pathogenesis of age-related macular degeneration (ARMD) is not clearly understood. Like other age-related diseases, it is associated with abnormal deposits called drusen. These drusens are localized in Bruch's membrane. Recent investigations have shown a link between drusen formation and inflammatory and immunologic reactions. The involvement of oxidative stress is supported by available data as an important contributing factor in the developement of ARMD. The data regarding the nature and the source of the deposits suggest that ARMD may share similar pathways with atherosclerosis. The role of oxydized products of cholesterol, the oxysterols, in the pathogenesis of atherosclerosis is well known. As cholesterol is a constituent of drusens, oxysterols could be involved in retinal pigment epithelium and photoreceptor lesions occurring in ARMD owing to their cytotoxic, pro-inflammatory, and pro-oxydant properties.

Side effects of oxysterols: cytotoxicity, oxidation, inflammation, and phospholipidosis

Oxysterols are 27-carbon atom molecules resulting from autoxidation or enzymatic oxidation of cholesterol. They are present in numerous foodstuffs and have been demonstrated to be present at increased levels in the plasma of patients with cardiovascular diseases and in atherosclerotic lesions. Thus, their role in lipid disorders is widely suspected, and they might also be involved in important degenerative diseases such as Alzheimer's disease, osteoporosis, and age-related macular degeneration. Since atherosclerosis is associated with the presence of apoptotic cells and with oxidative and inflammatory processes, the ability of some oxysterols, especially 7-ketocholesterol and 7beta-hydroxycholesterol, to trigger cell death, activate inflammation, and modulate lipid homeostasis is being extensively studied, especially in vitro. Thus, since there are a number of essential considerations regarding the physiological/pathophysiological functions and activities of the different oxysterols, it is important to determine their biological activities and identify their signaling pathways, when they are used either alone or as mixtures. Oxysterols may have cytotoxic, oxidative, and/or inflammatory effects, or none whatsoever. Moreover, a substantial accumulation of polar lipids in cytoplasmic multilamellar structures has been observed with cytotoxic oxysterols, suggesting that cytotoxic oxysterols are potent inducers of phospholipidosis. This basic knowledge about oxysterols contributes to a better understanding of the associated pathologies and may lead to new treatments and new drugs. Since oxysterols have a number of biological activities, and as oxysterol-induced cell death is assumed to take part in degenerative pathologies, the present review will focus on the cytotoxic activities of these compounds, the corresponding cell death signaling pathways, and associated events (oxidation, inflammation, and phospholipidosis).