Recent findings have upheld the hypothesis that environmental UV-radiation is a factor that contributes to human cataract formation. Our objectives are to study how environmental UV-exposure enhances cataractous changes in the lens and to explore conditions whereby antioxidants inhibit these changes. We will study squirrel and rabbit lenses in vitro, and their epithelial cells in culture. The results of parallel studies on fresh human intracapsularly extracted cataracts and eye bank lenses will be compared with those of animal data. How relevant the defects produced in animal lenses are to those of human aged and cataractous lenses will be assessed. The UV damages to be investigated are: lens epithelial cell anomalies, breakdown of F-actin, loss of ATP, oxidation of -SH groups, reduced activities of NA-K-ATPase, catalase, glutathione reductase, su- peroxide dismutase, DNA repair enzymes, and DNA single-strand breaks. Lens cell uptake of these antioxidants will be measured. We will compare photo- chemical changes in pure macromolecules and protection by these antioxidant with in vitro and cell culture data. Methods of analysis to follow UV-exposure are: immuno and histochemistry and histology, dye-binding, electron microscopy, biochemical assays of enzymes, ATP determination (by NMR), SH and SS determination, cell growth and survival, DNA strand breaks and characterization of lens epithelial cell DNA repair enzymes, protein analysis by gel isoelectric focusing HPLC, PAGE and immuno-blotting; loss of O2 from media. We hope to test biologically compatible chemical antioxidants to retard oxidation-related cataract formation.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
7R01EY000459-28
Application #
2772671
Study Section
Visual Sciences A Study Section (VISA)
Project Start
1977-05-01
Project End
2000-03-31
Budget Start
1998-07-01
Budget End
1999-03-31
Support Year
28
Fiscal Year
1998
Total Cost
Indirect Cost
Name
Boston University
Department
Ophthalmology
Type
Schools of Medicine
DUNS #
604483045
City
Boston
State
MA
Country
United States
Zip Code
02118
Zigman, S; McDaniel, T; Schultz, J et al. (2000) Effects of intermittent UVA exposure on cultured lens epithelial cells. Curr Eye Res 20:95-100
Atherton, S J; Lambert, C; Schultz, J et al. (1999) Fluorescence studies of lens epithelial cells and their constituents. Photochem Photobiol 70:823-8
Zigman, S; Schultz, J B; Schultz, M (1998) Measurement of oxygen production by in vitro human and animal lenses with an oxygen electrode. Curr Eye Res 17:115-9
DeMott, M S; Zigman, S; Bambara, R A (1998) Replication protein A stimulates long patch DNA base excision repair. J Biol Chem 273:27492-8
Rafferty, N S; Rafferty, K A; Zigman, S (1997) Comparative response to UV irradiation of cytoskeletal elements in rabbit and skate lens epithelial cells. Curr Eye Res 16:310-9
DeMott, M S; Shen, B; Park, M S et al. (1996) Human RAD2 homolog 1 5'- to 3'-exo/endonuclease can efficiently excise a displaced DNA fragment containing a 5'-terminal abasic lesion by endonuclease activity. J Biol Chem 271:30068-76
Zigman, S; Reddan, J; Schultz, J B et al. (1996) Structural and functional changes in catalase induced by near-UV radiation. Photochem Photobiol 63:818-24
Zigman, S; McDaniel, T; Schultz, J B et al. (1995) Damage to cultured lens epithelial cells of squirrels and rabbits by UV-A (99.9%) plus UV-B (0.1%) radiation and alpha tocopherol protection. Mol Cell Biochem 143:35-46
Zigman, S (1995) Environmental near-UV radiation and cataracts. Optom Vis Sci 72:899-901
Zigman, S; Rafferty, N S; Schultz, M (1995) Dogfish (Mustelus canis) lens catalase reduces H2O2-induced opacification. Biol Bull 189:222-3

Showing the most recent 10 out of 28 publications