Linked Life Data

17514531

Source:http://linkedlifedata.com/resource/pubmed/id/17514531

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2007-5-21
pubmed:abstractText
Glutathione reductase (GR) plays a key role in maintaining thiol groups in the lens, and its activity decreases with aging and cataract formation. Mammalian thioredoxin (Trx) and thioredoxin reductase (TrxR), or the Trx/TrxR system, participates in the repair of oxidatively damaged lens proteins and enzymes. Alpha-crystallin, a molecular chaperone, prevents the aggregation of partially denatured proteins under various stress conditions. Thioltransferase (TTase, or glutaredoxin) can maintain the homeostasis of lens protein thiols thus protecting against oxidative stress. We investigated whether the Trx/TrxR system can revive GR activity in both the cortex and nucleus of human cataract and clear aged lenses and whether alpha-crystallin and TTase can help this effect. The GR activity in the cortex and nucleus of the cataractous lenses was significantly lower than that of the aged clear lenses. The highest activity in the cortex was observed in the clear aged lenses. The combination of Trx and TrxR revived the activity of GR from both the cortex and nucleus of aged clear lenses. However, in cataract lenses (grade II and grade IV), there was a statistically significant recovery of GR activity in the cortex, but not in the nucleus. No recovery was observed when Trx or TrxR were used separately. Alpha-crystallin successfully revived GR activity in the cortex of cataract grade II lenses, but not in the nucleus. The combination of alpha-crystallin and Trx/TrxR gave a further increase of activity. TTase alone revived some of the GR activity but together with the Trx/TrxR system gave no statistically significant enhancement of GR activity. These results indicate that both disulfide bond formation and protein unfolding are responsible for GR inactivation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0271-3683
pubmed:author
pubmed:issnType
Print
pubmed:volume
32
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
455-63
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Revival of glutathione reductase in human cataractous and clear lens extracts by thioredoxin and thioredoxin reductase, in conjunction with alpha-crystallin or thioltransferase.
pubmed:affiliation
Department of Ophthalmology, Tangdu Hospital, Fourth Military Medical University, Xi'an 710038, China. yhongb@fmmu.edu.cn
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural