Abstract：
:The proteasomal pathway is responsible for processes essential for cell viability, including the selective degradation of oxidized proteins. An age-dependent loss in proteasome function has been reported in many tissues, but has not been examined in the retina. In this study, we evaluated proteasome function and protein oxidation in retinal homogenates from young adult and old F344BN rats. For retinal proteasome from old rats, we observed an 80% decrease in the rate of casein degradation and a 75% loss in chymotrypsin-like activity. This loss in activity could be partially accounted for by a 50% reduction in expression of the 20S proteasome. The regulatory complex PA700 and the inducible beta-subunit, LMP7, which is associated with the chymotrypsin-like activity, were expressed in equivalent concentrations relative to the 20S catalytic core in both young and old rats. Immunochemical analysis using antibodies that recognize the protein oxidative modifications, nitrotyrosine and 4-hydroxy-2-nonenal, showed that retinal proteins from old rats exhibited the greatest immunoreactivity. These results suggest that the age-related loss in proteasome function contributes to the accumulation of oxidized retinal proteins. Thus, the combined effect of an increase in oxidized proteins and inactivation of the protease responsible for ridding the cell of oxidized proteins places the aged retina at greater risk for irreversible damage caused by oxidative stress.
journal_name
Exp Eye Resjournal_title
Experimental eye researchauthors
Louie JL,Kapphahn RJ,Ferrington DAkeywords:
subject
Has Abstractpub_date
2002-09-01 00:00:00pages
271-84issue
3eissn
0014-4835issn
1096-0007pii
S0014483502920221journal_volume
75pub_type
杂志文章abstract：:Dysfunctional vascular endothelial nitric oxide synthase (eNOS) has been proposed to play a main pathophysiological role in various ocular diseases. The aim of the present study was to test the hypothesis that the chronic lack of eNOS impairs endothelium-dependent vasodilation in retinal arterioles. The relevance of e...
journal_title：Experimental eye research
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journal_title：Experimental eye research
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journal_title：Experimental eye research
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journal_title：Experimental eye research
pub_type： 杂志文章
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更新日期：2020-10-01 00:00:00
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journal_title：Experimental eye research
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journal_title：Experimental eye research
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journal_title：Experimental eye research
pub_type： 杂志文章
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journal_title：Experimental eye research
pub_type： 杂志文章
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更新日期：1992-01-01 00:00:00
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journal_title：Experimental eye research
pub_type： 杂志文章
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更新日期：1988-02-01 00:00:00
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journal_title：Experimental eye research
pub_type： 杂志文章
doi：10.1006/exer.1999.0703
更新日期：1999-09-01 00:00:00
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journal_title：Experimental eye research
pub_type： 杂志文章
doi：10.1016/j.exer.2011.10.007
更新日期：2011-12-01 00:00:00
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journal_title：Experimental eye research
pub_type： 杂志文章
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更新日期：2005-05-01 00:00:00
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journal_title：Experimental eye research
pub_type： 杂志文章
doi：10.1016/j.exer.2017.05.011
更新日期：2017-08-01 00:00:00
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journal_title：Experimental eye research
pub_type： 杂志文章
doi：10.1016/j.exer.2009.06.013
更新日期：2009-11-01 00:00:00
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journal_title：Experimental eye research
pub_type： 杂志文章
doi：10.1006/exer.2001.1080
更新日期：2001-11-01 00:00:00
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journal_title：Experimental eye research
pub_type： 杂志文章
doi：10.1016/j.exer.2005.04.007
更新日期：2005-12-01 00:00:00
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journal_title：Experimental eye research
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journal_title：Experimental eye research
pub_type： 杂志文章
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更新日期：2013-10-01 00:00:00
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journal_title：Experimental eye research
pub_type： 杂志文章
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更新日期：1984-06-01 00:00:00
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journal_title：Experimental eye research
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更新日期：2021-01-01 00:00:00
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journal_title：Experimental eye research
pub_type： 杂志文章
doi：10.1016/0014-4835(85)90136-8
更新日期：1985-05-01 00:00:00
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journal_title：Experimental eye research
pub_type： 杂志文章
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更新日期：2013-06-01 00:00:00
abstract：:There has been generally little attention paid to the utilization of biomaterials as an anti-myopia treatment. The purpose of this study was to investigate whether polymeric hydrogels, either implanted or injected adjacent to the outer scleral surface, slow ocular elongation. White Leghorn (Gallus gallus domesticus) c...
journal_title：Experimental eye research
pub_type： 杂志文章
doi：10.1016/j.exer.2008.10.029
更新日期：2009-03-01 00:00:00
