Is hypochlorous acid (HOCl) involved in age-related nuclear cataract?
BACKGROUND
Oxidative damage to lens proteins is associated with human age-related nuclear cataract and H2O2 has been implicated. As hypochlorous acid (HOCl) can be formed from chloride ions and H2O2 and many of the protein modifications observed in cataract are also noted following exposure of proteins to HOCl, age-related nuclear cataract lenses were examined for evidence of HOCl-mediated alterations.


METHODS
Three techniques were employed using human lens samples: 1. staining with a HOP antibody that recognises HOCl-treated proteins, 2. myeloperoxidase assays and 3. measurement of chlorotyrosine in acid digests of the crystallins.


RESULTS
HOP staining was inconclusive, although cataract lenses appeared to stain more intensely than normals. No myeloperoxidase activity could be detected and neither mono- nor di-chlorotyrosine could be found in human lens proteins.


CONCLUSIONS
On the basis of this study, no evidence was obtained to support a role for HOCl in age-related nuclear cataract.
Hazell
Linda J
LJ
The Heart Research Institute, University of Wollongong, NSW, Australia.
Fu
HongJie
H
Dean
Roger T
RT
Stocker
Roland
R
Truscott
Roger J W
RJ
D000375:Aging / Q000378:metabolism*; D000911:Antibodies, Monoclonal; D002386:Cataract / Q000378:metabolism*; D006801:Humans; D006997:Hypochlorous Acid / Q000378:metabolism*; D007124:Immunoenzyme Techniques; D007907:Lens Nucleus, Crystalline / Q000378:metabolism*; D009195:Peroxidase / Q000378:metabolism
D000911:Antibodies, Monoclonal; D006997:Hypochlorous Acid; D009195:Peroxidase