Clinically relevant metabolic studies of the cornea using redox fluorometry are proposed. Corneal redox fluorometry, a method originally developed in this laboratory, measures the biochemical state of the cornea in a non- invasive and non-destructive manner that has the capability of clinical application. The method applied clinically, would be invaluable both as a diagnostic tool and as a method for evaluation of treatment. No other currently available method provides the same essential information for the clinician. Corneal redox fluorometry measures the fluorescence of reduced pyridine nucleotides and oxidized flavoproteins and this provides an index of cellular oxidation-reduction (redox) state. Measurements of this fluorescence and the amount of light scattering in the tissue as a function of corneal depth will be made using confocal microscopy to enable separation of the endothelial and epithelial signals from the stromal signal. In addition, the redox state of single cells and the differences in metabolic state between individual cells within the corneal endothelium and within the corneal epithelium will be measured. The experiments proposed are clinically relevant and designed to provide knowledge that will be directly applicable to providing better health care. The measurements will be made in perfused corneas in vitro and in animal in vivo. The proposed experiments will focus on investigating the corneal metabolic changes that occur during decreased oxygen availability, wound healing, corneal storage, and corneal disease. The non-invasive measurements will be correlated with histological and electron microscopic studies made on the same tissue. The possibility of applying the methods developed to clinical diagnosis and treatment will also be investigated and animal measurements necessary to obtain approval for human measurements will be made.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY001990-08
Application #
3256375
Study Section
Visual Sciences A Study Section (VISA)
Project Start
1977-09-01
Project End
1993-03-31
Budget Start
1991-04-01
Budget End
1992-03-31
Support Year
8
Fiscal Year
1991
Total Cost
Indirect Cost
Name
Boston University
Department
Type
Schools of Medicine
DUNS #
604483045
City
Boston
State
MA
Country
United States
Zip Code
02118
Shimazaki, J; Tsubota, K; Yoshida, A et al. (1995) Changes of corneal redox state in diabetic animal models. Cornea 14:196-201
Shimazaki, J; Tsubota, K; Hayashi, K et al. (1993) Distribution of autofluorescence in the rabbit corneal epithelium. Ophthalmic Res 25:220-5
Laing, R A; Chiba, K; Tsubota, K et al. (1992) Metabolic and morphologic changes in the corneal endothelium. The effects of potassium cyanide, iodoacetamide, and ouabain. Invest Ophthalmol Vis Sci 33:3315-24
Tsubota, K; Laing, R A (1992) Glycolytic oscillation and effect of metabolic inhibitor on rat lens. Jpn J Ophthalmol 36:265-72
Tsubota, K; Laing, R A (1992) Metabolic changes in the corneal epithelium resulting from hard contact lens wear. Cornea 11:121-6
Shimazaki, J; Tornheim, K; Laing, R A (1989) Correlation of redox fluorometry and analytical measurements of pyridine nucleotide. Invest Ophthalmol Vis Sci 30:2274-8
Tsubota, K; Krauss, J M; Kenyon, K R et al. (1989) Lens redox fluorometry: pyridine nucleotide fluorescence and analysis of diabetic lens. Exp Eye Res 49:321-34
Tsubota, K; Laing, R A; Chiba, K et al. (1988) Noninvasive metabolic analysis of preserved rabbit cornea. Arch Ophthalmol 106:1713-7
Tsubota, K; Laing, R A; Kenyon, K R (1987) Noninvasive measurements of pyridine nucleotide and flavoprotein in the lens. Invest Ophthalmol Vis Sci 28:785-9