Search

Your search keyword '"THORPE, SUZANNE R."' showing total 312 results
Start Over Author "THORPE, SUZANNE R."
312 results on '"THORPE, SUZANNE R."'

5. Mice deficient in both Mn superoxide dismutase and glutathione peroxidase-1 have increased oxidative damage and a greater incidence of pathology but no reduction in longevity

Author

Zhang, Yiqiang, Ikeno, Yuji, Qi, Wenbo, Chaudhuri, Asish, Li, Yan, Bokov, Alex, Thorpe, Suzanne R., Baynes, John W., Epstein, Charles, Richardson, Arlan, and Van Remmen, Holly

Subjects
Superoxide dismutase -- Health aspects, Mice -- Health aspects, Mice -- Physiological aspects, Oxidative stress -- Research, Health, Seniors
Abstract

To test the impact of increased mitochondrial oxidative stress as a mechanism underlying aging and age-related pathologies, we generated mice with a combined deficiency in two mitochondrial-localized antioxidant enzymes, Mn superoxide dismutase (MnSOD) and glutathione peroxidase-1 (Gpx-1). We compared life span, pathology, and oxidative damage in [Gpx1.sup.-/]-, [Sod2.sup.+/]-[Gpx1.sup.1+/]-, [Sod2.sup.+/]-[Gpx1.sup.-/]-, and wild-type control mice. Oxidative damage was elevated in [Sod2.sup.+/]-[Gpx1.sup.-/]mice, as shown by increased DNA oxidation in liver and skeletal muscle and increased protein oxidation in brain. Surprisingly, [Sod2.sup.+/]-[Gpx1.sup.-/]- mice showed no reduction in life span, despite increased levels of oxidative damage. Consistent with the important role for oxidative stress in tumorigenesis during aging, the incidence of neoplasms was significantly increased in the older [Sod2.sup.+/]-[Gpx1.sup.-/]- mice (28-30 months). Thus, these data do not support a significant role for increased oxidative stress as a result of compromised mitochondrial antioxidant defenses in modulating life span in mice and do not support the oxidative stress theory of aging. Key Words: Oxidative stress--Longevity. doi: 10.1093/gerona/glp132

Published
2009

17. Dietary Bread Crust Advanced Glycation End Products Bind to the Receptor for AGEs in HEK-293 Kidney Cells but Are Rapidly Excreted after Oral Administration to Healthy and Subtotally Nephrectomized Rats

Author

SOMOZA, VERONIKA, LINDENMEIER, MICHAEL, HOFMANN, THOMAS, FRANK, OLIVER, ERBERSDOBLER, HELMUT F., BAYNES, JOHN W., THORPE, SUZANNE R., HEIDLAND, AUGUST, ZILL, HOLGER, BEK, STEPHAN, HUBER, JOCHEN, WEIGLE, THOMAS, SCHEIDLER, SABINE, BUSCH, ANDREAS E., and ŠEBEKOVÁ, KATARÍNA

Published
2005

23. Preface

Author

BAYNES, JOHN W., MONNIER, VINCENT M., AMES, JENNIFER M., and THORPE, SUZANNE R.

Published
2005

25. Caloric restriction decreases age-dependent accumulation of the glycoxidation products, N(super epsilon)-(carboxymethyl)lysine and pentosidine, in rat skin collagen

Author

Cefalu, William T., Bell-Farrow, Audrey D., Wang, Zhong Q., Sonntag, William E., Fu, Min-Xin, Baynes, John W., and Thorpe, Suzanne R.

Subjects
Skin -- Health aspects, Low-calorie diet -- Physiological aspects, Aging -- Health aspects, Collagen -- Health aspects, Health, Seniors
Abstract

Nonenzymatic glycation of body proteins and subsequent advanced glycation reactions have been implicated in the aging process, while caloric restriction (CR) in rodents results in an increase in both mean and maximum life span. We have evaluated the effect of chronic (25 months) CR on glycation of blood proteins and accumulation of advanced glycation and oxidation (glycoxidation) products, [N.sup.[epsilon]] (carboxymethyl)lysine (CML), and pentosidine, in skin collagen. Brown-Norway rats, fed ad libitum (AL) from birth, were divided into two equal groups at 4 months of age and placed on AL or CR diets (CR = 60% of AL diet). Cohorts of animals were sacrificed at 7, 13, and 25 months after the initiation of CR. At necropsy glycated hemoglobin was measured by affinity HPLC and glycated plasma protein by the fructosamine assay; extracts of skin collagen were analyzed by gas chromatography-mass spectrometry for CML and by reversed-phase HPLC for pentosidine. Glycation of hemoglobin, plasma proteins, and skin collagen was decreased significantly 18-33%) by CR. Concentrations of CML and pentosidine increased significantly with age in skin collgen in both AL and CR animals; however, CR significantly reduced levels of CML (25%), pentosidine (50%), and fluorescence (15%) in collagen in the oldest rats. We conclude that CR reduces the extent of glycation of blood and tissue proteins and the age-related accumulation of glycoxidation products in skin collagen.

Published
1995

26. N(super epsilon)-(carboxymethyl)lysine is a dominant advanced glycation end product (AGE) antigen in tissue proteins

Author

Reddy, Sharanya, Bichler, Johann, Wells-Knecht, Kevin J., Thorpe, Suzanne R., and Baynes, John W.

Subjects
Lysine -- Analysis, Antigen-antibody reactions -- Analysis, Proteins -- Structure, Biological sciences, Chemistry
Abstract

Analysis of the structure advanced glycation end products (AGE's) by preparing antibodies by permeation chromatographic showed a similar advanced glycation end products (AGEs) are formed in the reactions of N(super alpha)-acetyllysine with glucose, fructose, and glyoxal, which co-eluted with authentic N(super epsilon)-acetyl-N(super alpha)-(carboxymethyl)lysine. The amino acid analysis revealed a similarity with N(super epsilon)-(carboxymethyl)lysine. This results suggest that AGEs are glycoxidation products.

Published
1995

27. Mechanism of autoxidative glycosylation: identification of glyoxal and arabinose as intermediates in the autoxidative modification of proteins by glucose

Author

Wells-Knecht, Kevin J., Zyzak, David V., Litchfield, John E., Thorpe, Suzanne R., and Baynes, John W.

Subjects
Proteins -- Crosslinking, Glycosylation -- Analysis, Oxidation-reduction reaction -- Analysis, Biological sciences, Chemistry
Abstract

Analysis of the mechanism of autoxidative glycosylation of proteins suggest that glyoxal and arabinoses are the intermediates in the autoxidative browning and crosslinking proteins by glucose. Glyoxal serves as the alpha-dicarbonyl sugar and arabinose as the pentose formed upon autoxidation of glucose. The results provide a restriction of glycoxidation reactions by antioxidants and dicarbonyl trapping reagents such as aminoguanidine.

Published
1995

35. Nonenzymatic glycosylation of protein does not increase with age in normal human lenses

Author

Patrick, Jeffrey S., Thorpe, Suzanne R., and Baynes, John W.

Subjects
Eye diseases -- Demographic aspects, Diabetes -- Research, Glycoproteins, Glycosylation -- Abnormalities, Diabetes -- Complications, Health, Seniors
Abstract

It has long been thought that a metabolic process called nonenzymatic (i.e. not caused by enzymes) glycosylation or glycation, associated with aging, was responsible for the cataracts seen with aging or in diabetics. Diabetes, in turn, has been described as a disease of accelerated aging because so much of the pathology (disease) or complications associated with it are similar to those seen with advancing age. Glycation involves a reaction between glucose (sugar) and certain residues in protein. Some researchers say that there are continuous age-related increases in glycation in some of the longer-lived proteins in the body; others say that glycation can be reversed. These authors suggest that the increases and reversals in glycation should reach an equilibrium at some point and so under the best of conditions, age-related increases in glycation should be minimal. To test that hypothesis, the relationship between age and the extent of glycation in the lens of the eye was studied, and it was found that there is, indeed, equilibrium under certain conditions. Moreover, the increases in glycation of protein in diabetes are related to the amount of glucose in the blood (glycemia), and improving diabetic control may have long-term beneficial effects in slowing the development of complications. (Consumer Summary produced by Reliance Medical Information, Inc.)

Published
1990

44. 3-deoxyfructose concentrations are increased in human plasma and urine in diabetes

Author

Wells-Knecht, Kevin J., Lyons, Timothy J., McCance, David R., Thorpe, Suzanne R., Feather, Milton S., and Baynes, John W.

Subjects
Urine -- Analysis, Deoxy sugars -- Physiological aspects -- Analysis, Hyperglycemia -- Complications and side effects, Health, Analysis, Physiological aspects, Complications and side effects
Abstract

3-Deoxyglucosone (3-DG) is a reactive dicarbonyl sugar thought to be a key intermediate in the nonenzymatic polymerization and browning of proteins by glucose. 3-DG may be formed in vivo from [...]

Published
1994

45. Glycation, glycoxidation, and cross-linking of collagen by glucose: kinetics, mechanisms, and inhibition of late stages of the Maillard reaction

Author

Fu, Min-Xin, Wells-Knecht, Kevin J., Blackledge, James A., Lyons, Timothy J., Thorpe, Suzanne R., and Baynes, John W.

Subjects
Diabetes -- Physiological aspects, Glucose metabolism -- Physiological aspects, Health, Physiological aspects
Abstract

Kinetics, Mechanisms, and Inhibition of Late Stages of the Maillard Reaction The Maillard or browning reaction between sugar and protein contributes to the increased chemical modification and cross-linking of long-lived [...]

Published
1994

46. Role of oxygen in cross-linking and chemical modification of collagen by glucose

Author

Fu, Min-Xin, Knecht, Kevin J., Thorpe, Suzanne R., and Baynes, John W.

Subjects
Crosslinked polymers -- Physiological aspects, Oxygen -- Physiological aspects, Collagen -- Physiological aspects, Glucose metabolism -- Physiological aspects, Proteins -- Crosslinking, Health, Physiological aspects
Abstract

The role of oxygen in chemical modification and cross-linking of rat tall collagen by glucose was studied at physiological pH and temperature in vitro. Cross-linking of collagen under air depended [...]

Published
1992

Catalog

Books, media, physical & digital resources
See catalog results