The Action of aldose reductase (EC 1.1.1.21; """"""""low-Km"""""""" aldehyde reductase; ALR2) is implicated in the etiology of diabetic complications of the eye, kidney, heart, and nerve. The ability of specific aldose reductase inhibitors (ARIs) to prevent the development of complications (basement membrane thickening, renal hypertrophy, defective axonal transport and nerve conduction velocity) in various tissues has confirmed the central role of ALR2 in normal and diabetic metabolism. This conclusion is supported by immunologic evidence for phylogenetic conservation of the mammalian ALR2 gene product. Homogeneous bovine kidney ALR2 (BKALR2) is virtually identical to bovine lens ALR2, but only after the BKALR2 has undergone a slow, thiol-dependent activation to a stable form. The activation process, which results in alteration of the kinetic behavior (decreased sensitivity to inhibition by Sorbinil, decreased stimulation by sulfate, appearance of non-linearity in the double-reciprocal plot for glyceraldehyde), is relevant to the activation and variable ARI sensitivity seen in human tissues. Further mechanistic studies using homogeneous BKALR2 will focus on characterization of the activation process using kinetic and immunologic techniques, identification of the physiological substrate by structure-activity studies, and determination of the mode of ARI inhibition. The extension of these studies to human kidney ALR2 and """"""""high-Km"""""""" aldehyde reductase will utilize mon-specific rabbit anti-BKALR2 for the isolation and characterization of HKALR2. Key experiments, based on the results from the bovine system, will evaluate the mode and sensitivity to ARI inhibition, and the role of activation (as documented for BKALR2) in the human system.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK032218-06
Application #
3230644
Study Section
Biochemistry Study Section (BIO)
Project Start
1983-04-01
Project End
1990-05-31
Budget Start
1988-06-01
Budget End
1990-05-31
Support Year
6
Fiscal Year
1988
Total Cost
Indirect Cost
Name
Scripps Research Institute
Department
Type
DUNS #
City
San Diego
State
CA
Country
United States
Zip Code
92037
Grimshaw, C E (1991) Enantiospecific change in products for aldose reductase-mediated reaction of glyceraldehyde with bound NADP+. Biochem Biophys Res Commun 175:943-8
Grimshaw, C E (1991) A kinetic perspective on the peculiarity of aldose reductase. Adv Exp Med Biol 284:217-28
Grimshaw, C E (1990) Chromatographic separation of activated and unactivated forms of aldose reductase. Arch Biochem Biophys 278:273-6
Schade, S Z; Early, S L; Williams, T R et al. (1990) Sequence analysis of bovine lens aldose reductase. J Biol Chem 265:3628-35
Grimshaw, C E; Shahbaz, M; Putney, C G (1990) Spectroscopic and kinetic characterization of nonenzymic and aldose reductase mediated covalent NADP-glycolaldehyde adduct formation. Biochemistry 29:9936-46
Grimshaw, C E; Shahbaz, M; Putney, C G (1990) Mechanistic basis for nonlinear kinetics of aldehyde reduction catalyzed by aldose reductase. Biochemistry 29:9947-55
Grimshaw, C E; Shahbaz, M; Jahangiri, G et al. (1989) Kinetic and structural effects of activation of bovine kidney aldose reductase. Biochemistry 28:5343-53
Grimshaw, C E; Mathur, E J (1989) Immunoquantitation of aldose reductase in human tissues. Anal Biochem 176:66-71