[Change of alpha-crystallin acting as molecular chaperone activity with ageing].
OBJECTIVE
To evaluate the molecular chaperone function of alpha-crystallin with ageing.


METHODS
alpha-Crystallin of newborn, adult and old rabbits lenses in both of cortex and nucleus were separated by chromatography on Sephacryl S-300HR. The protection of alpha-crystallin against thermal aggregation of catalase and beta L-crystallin (60 degrees C), inactivation of catalase by fructose(37 degrees C) and heat stress(60 degrees C) were measured spectrophotometrically.


RESULTS
Protection of alpha-crystallin against aggregation and inactivation using four methods showed a similar pattern. The protective ability in cortex was greatly higher than in nucleus of different-aged lenses, and alpha H-crystallin was less than alpha L-crystallin in both cortex and nucleus. There was no statistically decrease with age of chaperone function of both alpha H-crystallin and alpha L-crystallin in the cortex, whereas alpha L-crystallin in the nucleus was compromised.


CONCLUSIONS
alpha-Crystallin in the nucleus shows age-related decrease in chaperone function, which may be responsible for cataract formation.
Yan
Hong
H
Department of Ophthalmology, Tangdu Hospital, Fourth Military Medical University, Xi'an 710038, China.
Hui
Yanninan
Y
Fan
Jiangguo
J
Wang
Weinong
W
D000375:Aging; D000818:Animals; D000831:Animals, Newborn; D002374:Catalase / Q000378:metabolism; D007908:Lens, Crystalline / Q000737:chemistry*; D018832:Molecular Chaperones / Q000378:metabolism*; D011817:Rabbits; D038201:alpha-Crystallins / Q000378:metabolism*; D038204:beta-Crystallins / Q000378:metabolism
D018832:Molecular Chaperones; D038201:alpha-Crystallins; D038204:beta-Crystallins; D002374:Catalase