Fluorescence and immunochemical studies of advanced glycation-related lens pigments.
OBJECTIVE
To establish whether advanced glycation is the major mechanism for yellowing of lens proteins.


METHODS
Synchronous fluorescence (SF) and immunochemical assays were used to study glycation in vitro and in vivo. In the in vitro study, advanced glycation end products (AGEs) were prepared and used as antigens to induce antibodies to AGEs. The in vitro AGEs and classified nuclear cataracts were analyzed by SF and immunochemical assays.


RESULTS
In vitro AGEs generated from various glycating agents and carrier proteins displayed strong SF above 350 nm; the spectra were well resolved with major bands at 380 nm and 420 nm. Samples from human lenses manifested a band at 395 nm in addition to the two bands shown by in vitro AGEs. SF intensity is greater for the water-insoluble (WI) than water-soluble (WS) fraction, but both increased with increasing nuclear color. The immunoreactivity data also showed that the WI fraction contained more AGEs than the WS fraction and that the amount of AGEs increased with increasing nuclear color.


CONCLUSIONS
Fluorescence and immunoassays indicated that pigmented AGEs contributed to yellowing of the crystalline lens nucleus.
Das
B K
BK
Center for Ophthalmic Research, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA.
Sun
T X
TX
Akhtar
N J
NJ
Chylack
L T
LT
Liang
J J
JJ
D000818:Animals; D015153:Blotting, Western; D002386:Cataract / Q000378:metabolism*; D002417:Cattle; D003459:Crystallins / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D017127:Glycation End Products, Advanced / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D006031:Glycosylation; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007908:Lens, Crystalline / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D010858:Pigmentation; D011817:Rabbits; D013050:Spectrometry, Fluorescence
D003459:Crystallins; D017127:Glycation End Products, Advanced; D007074:Immunoglobulin G