Oxidative Damage and Responses in Retinal Nuclei Arising from Intense Light Exposure

To evaluate the effects of filtering short wavelength light on visual performance under intense light conditions among pseudophakic patients previously implanted with a clear intraocular lens (IOL). This was a patient-masked, randomized crossover study conducted at 6 clinical sites in the United States between September 2013 and January 2014. One hundred fifty-four bilaterally pseudophakic patients were recruited. Photostress recovery time and glare disability thresholds were measured with clip-on blue-light-filtering and placebo (clear; no blue-light filtration) glasses worn over patients’ habitual correction. Photostress recovery time was quantified as the time necessary to regain sight of a grating target after intense light exposure. Glare disability threshold was assessed as the intensity of a white-light annulus necessary to obscure a central target. The order of filter used and test eye were randomized across patients. Photostress recovery time and glare disability thresholds were significantly improved (bothP<0.0001) when patients used blue-light-filtering glasses compared with clear, nonfiltering glasses. Compared with a nonfiltering placebo, adding a clip-on blue-absorbing filter to the glasses of pseudophakic patients implanted with clear IOLs significantly increased their ability to cope with glare and to recover normal viewing after an intensive photostress. This result implies that IOL designs with blue-light-filtering characteristics may be beneficial under intense light conditions.

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Changes in clusterin expression associated with light-induced retinal damage in rats

Biochemistry and Cell Biology ◽

10.1139/o94-067 ◽

1994 ◽

Vol 72 (11-12) ◽

pp. 499-503 ◽

Cited By ~ 14

Author(s):

P. Wong ◽

R. K. Kutty ◽

R. M. Darrow ◽

S. Shivaram ◽

G. Kutty ◽

...

Keyword(s):

Steady State ◽

Oxidative Damage ◽

Photoreceptor Cell ◽

Light Exposure ◽

Green Light ◽

Albino Rats ◽

Initial Increase ◽

Mrna Levels ◽

Retinal Damage ◽

Cell Degeneration

Prolonged periods of high-intensity visible light exposure lead to photoreceptor cell degeneration, but the mechanism of damage is not understood. Increased clusterin mRNA levels have been found in several models of apoptosis, as well as in neurodegeneration. We report here that changes in clusterin mRNA levels are also associated with light-induced retinal damage in adult male albino rats. Animals previously maintained in darkness or a weak cyclic light environment were exposed to intense visible green light for up to 24 h. Some rats were pretreated with a synthetic antioxidant, dimethylthiourea (DMTU), which reduces photoreceptor cell degeneration. Clusterin mRNA steady-state levels increased with the duration of light exposure in both cyclic light and dark reared animals, suggesting that an apoptotic mechanism may be involved. Animals pretreated with DMTU showed a delay in the initial increase in clusterin mRNA levels, suggesting that oxidative damage is involved in the damage mechanism. However, the incomplete suppression of increasing steady-state clusterin mRNA levels by DMTU suggests that either oxidative damage triggers a second pathway or multiple damage mechanisms are induced in the retina by light exposure.Key words: retinal degeneration, clusterin, apoptosis, retinitis pigmentosa.

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Proteomic Changes in the Photoreceptor Outer Segment upon Intense Light Exposure

Journal of Proteome Research ◽

10.1021/pr900819k ◽

2010 ◽

Vol 9 (2) ◽

pp. 1173-1181 ◽

Cited By ~ 13

Author(s):

Dagmar Hajkova ◽

Yoshikazu Imanishi ◽

Vikram Palamalai ◽

K. C. Sekhar Rao ◽

Chao Yuan ◽

...

Keyword(s):

Outer Segment ◽

Light Exposure ◽

Photoreceptor Outer Segment ◽

Intense Light

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Erythrophagocytosis in the Liver in Hemolytic Anemias

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100664 ◽

1968 ◽

Vol 26 ◽

pp. 184-185

Author(s):

O. T. Minick ◽

E. Orfei ◽

F. Volini ◽

G. Kent

Keyword(s):

Acid Phosphatase ◽

Oxidative Damage ◽

Phosphatase Activity ◽

Kupffer Cells ◽

Acid Phosphatase Activity ◽

Common Type ◽

Red Cell ◽

Cell Fragments ◽

Reticulo Endothelial System ◽

Important Site

Hemolytic anemias were produced in rats by administering phenylhydrazine or anti-erythrocytic (rooster) serum, the latter having agglutinin and hemolysin titers exceeding 1:1000.Following administration of phenylhydrazine, the erythrocytes undergo oxidative damage and are removed from the circulation by the cells of the reticulo-endothelial system, predominantly by the spleen. With increasing dosage or if animals are splenectomized, the Kupffer cells become an important site of sequestration and are greatly hypertrophied. Whole red cells are the most common type engulfed; they are broken down in digestive vacuoles, as shown by the presence of acid phosphatase activity (Fig. 1). Heinz body material and membranes persist longer than native hemoglobin. With larger doses of phenylhydrazine, erythrocytes undergo intravascular fragmentation, and the particles phagocytized are now mainly red cell fragments of varying sizes (Fig. 2).

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