Long-term objectives are (i) to advance knowledge of lipid peroxidation in animal tissues, with a major focus on the interaction of toxic initiators and antioxygenic protectors as determined by differential biochemical damage to lipids, proteins, and nucleic acids; and (ii) to evaluate antioxidant systems in living animals. Lipid peroxidation is involved in many disease processes and chemical toxicities. Protection is provided by biological antioxidants, and some requiring further evaluation will be studied.
Specific aims are: 1. To utilize in vitro systems to measure lipid peroxidation in animal tissues and cells. a. To compare the susceptibility of various animals organs to lipid peroxidation using tissue slices, organ homogenates,a nd hepatocytes as in vitro model test systems, with emphasis being placed on the tissue slice system. b. To determine the relative capacities of various toxic compounds as initiators of lipid peroxidation, and to determine the additive or synergistic effects of mixtures of toxic compounds as initiators of lipid peroxidation. c. To determine the relative protective capabilities of antioxidants and multiple antioxygenic systems against potent peroxidation initiators. 2. For application to a wide range of potential lipid peroxidation initiators, develop in vitro tissue assays that may become substitutes for or supplements to whole-animal assays currently used to determine some chemical toxicities. These assays will be used to evaluate single and multiple antioxygenic systems in tissues. 3. In tissue slices and hepatocytes, quantitate lipid peroxidation molecular damage to lipids, proteins and enzymes, nucleic acids, and other biomolecules. For screening initiators (halogenated hydrocarbons and peroxides) and antioxidants, thiobarbituric acid-reactive substances; release of ethane and pentane; aldehydes; decrease in polyunsaturated fatty acids; formation of conjugated dienes; release of free fatty acids; incorporation of radiolabeled amino acids into slices; oxygen consumption; efflux of glutathione; changes in mitochondrial enzymes; isolation of DNA for determination of template activity, electrophoresis of transcribed mRNA, DNA crosslinks, and tryptophan bound to DNA; oxidation of flavins; changes in heme pigments; electrophoretic changes in specific proteins that may be polymerized; oxidation of methionine; and release of hydrogen sulfide. 4. To determine in vivo protection against lipid peroxidation by biological compounds for which antioxygenic capacity has not been adequately determined, including beta-carotene, uric acid, coenzyme Q10, and (+)-catechin. 5. To quantitate additive effects or synergism among antioxidants, including beta-carotene, uric acid, coenzyme Q10, (+)-catechin, vitamin E, and selenium. To measure protection by dietary or injected antioxidants, high level lipid peroxidation will be produced in rats by injection of iron dextran or methyl ethyl ketone peroxide. Noninvasive measurements of expired ethane and pentane will be made, and hydrocarbon gas data will be correlated with data on erythrocyte hemolysis, peroxidizability of tissues, thiobarbituric acid-reactive substances in urine, and lipid-soluble fluorophores in spleen.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK039225-02
Application #
3239002
Study Section
Toxicology Study Section (TOX)
Project Start
1987-08-01
Project End
1992-07-31
Budget Start
1988-08-01
Budget End
1989-07-31
Support Year
2
Fiscal Year
1988
Total Cost
Indirect Cost
Name
University of California Davis
Department
Type
Earth Sciences/Resources
DUNS #
094878337
City
Davis
State
CA
Country
United States
Zip Code
95618
Weinberg, J M; Venkatachalam, M A; Roeser, N F et al. (2000) Mitochondrial dysfunction during hypoxia/reoxygenation and its correction by anaerobic metabolism of citric acid cycle intermediates. Proc Natl Acad Sci U S A 97:2826-31
Van Vliet, A I; Van Alderwegen, I E; Baelde, H J et al. (1999) Differential expression of collagen type IV alpha-chains in the tubulointerstitial compartment in experimental chronic serum sickness nephritis. J Pathol 189:279-87
Minto, A W; Kalluri, R; Togawa, M et al. (1998) Augmented expression of glomerular basement membrane specific type IV collagen isoforms (alpha3-alpha5) in experimental membranous nephropathy. Proc Assoc Am Physicians 110:207-17
Bergijk, E C; Van Alderwegen, I E; Baelde, H J et al. (1998) Differential expression of collagen IV isoforms in experimental glomerulosclerosis. J Pathol 184:307-15
Chen, H; Tappel, A L (1995) Protection of vitamin E, selenium, trolox C, ascorbic acid palmitate, acetylcysteine, coenzyme Q0, coenzyme Q10, beta-carotene, canthaxanthin, and (+)-catechin against oxidative damage to rat blood and tissues in vivo. Free Radic Biol Med 18:949-53
Chen, H; Tappel, A L (1995) Vitamin E, selenium, trolox C, ascorbic acid palmitate, acetylcysteine, coenzyme Q, beta-carotene, canthaxanthin, and (+)-catechin protect against oxidative damage to kidney, heart, lung and spleen. Free Radic Res 22:177-86
Andersen, H J; Pellett, L; Tappel, A L (1994) Hemichrome formation, lipid peroxidation, enzyme inactivation and protein degradation as indexes of oxidative damage in homogenates of chicken kidney and liver. Chem Biol Interact 93:155-69
Venkatachalam, M A; Weinberg, J M (1994) Mechanisms of cell injury in ATP-depleted proximal tubules. Role of glycine, calcium, and polyphosphoinositides. Nephrol Dial Transplant 9 Suppl 4:15-21
Chen, H; Tappel, A L (1994) Protection by vitamin E selenium, trolox C, ascorbic acid palmitate, acetylcysteine, coenzyme Q, beta-carotene, canthaxanthin, and (+)-catechin against oxidative damage to liver slices measured by oxidized heme proteins. Free Radic Biol Med 16:437-44
Chen, H; Tappel, A L; Boyle, R C (1993) Oxidation of heme proteins as a measure of oxidative damage to liver tissue slices. Free Radic Biol Med 14:509-17

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