Identification of the new UV filter compound cysteine-L-3-hydroxykynurenine O-beta-d-glucoside in human lenses.
UV filters protect the human lens and retina from UV light-induced damage. Here, we report the identification of a new UV filter, cysteine-l-3-hydroxykynurenine O-beta-d-glucoside, which is present in older normal human lenses. Its structure was confirmed by independent synthesis. It is likely this novel UV filter is formed in the lens by nucleophilic attack of cysteine on the unsaturated ketone derived from deamination of 3-hydroxykynurenine O-beta-d-glucoside. Quantitation studies revealed considerable variation in normal lens levels that may be traced to the marked instability of the cysteine adduct. The novel UV filter was not detected in advanced nuclear cataract lenses.
Hains
Peter G
PG
Save Sight Institute, University of Sydney, Sydney, NSW 2001, Australia.
Mizdrak
Jasminka
J
Streete
Isla M
IM
Jamie
Joanne F
JF
Truscott
Roger J W
RJ
D000368:Aged; D002851:Chromatography, High Pressure Liquid; D004151:Dipeptides / Q000032:analysis* / Q000737:chemistry; D005960:Glucosides / Q000032:analysis* / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007908:Lens, Crystalline / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D013816:Thermodynamics; D014466:Ultraviolet Rays
C402223:3-hydroxykynurenine glucoside; D004151:Dipeptides; D005960:Glucosides; C514344:cysteine-3-hydroxykynurenine O-glucoside