Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 3 of 3
Full-Text Articles in Physical Sciences and Mathematics
Formation Of Pentosidine During Nonenzymatic Browning Of Proteins By Glucose, Daniel G. Dyer, James A. Blackledge, Suzanne R. Thorpe, John W. Baynes
Formation Of Pentosidine During Nonenzymatic Browning Of Proteins By Glucose, Daniel G. Dyer, James A. Blackledge, Suzanne R. Thorpe, John W. Baynes
Faculty Publications
A fluorescent compound has been detected in proteins browned during Maillard reactions with glucose in vitro and shown to be identical to pentosidine, a pentose- derived fluorescent cross-link formed between arginine and lysine residues in collagen (Sell, D. R., and Monnier, V. M. (1989) J. Biol. Chem. 264, 21597- 2 1602). Pentosidine was the major fluorophore formed during nonenzymatic browning of ribonuclease and lysozyme by glucose, but accounted for <1% of nondisulfide cross-links in protein dimers formed during the reaction. Pentosidine was formed in greatest yields in reactions of pentoses with lysine and arginine in model systems but was also formed from glucose, fructose, ascorbate, Amadori compounds, 3-deoxyglucosone, and other sugars. Pentosidine was not formed from peroxidized polyunsaturated fatty acids or malondialdehyde. Its formation from carbohydrates was inhibited under nitrogen or anaerobic conditions and by aminoguanidine, an inhibitor of advanced glycation and browning reactions. Pentosidine was detected in human lens proteins, where its concentration increased gradually with age, but it did not exceed trace concentrations (55 Fmol/mol lysine), even in the 80-year-old lens. Although its precise carbohydrate source in vivo is uncertain and it is present in only trace concentrations in tissue proteins, pentosidine appears to be a useful biomarker for assessing cumulative damage to proteins by nonenzymatic browning reactions with carbohydrates.
Decrease In Skin Collagen Glycation With Improved Glycemic Control In Patients With Insulin-Dependent Diabetes Mellitus, Timothy J. Lyons, Karen E. Bailie, Daniel G. Dyer, John A. Dunn, John W. Baynes
Decrease In Skin Collagen Glycation With Improved Glycemic Control In Patients With Insulin-Dependent Diabetes Mellitus, Timothy J. Lyons, Karen E. Bailie, Daniel G. Dyer, John A. Dunn, John W. Baynes
Faculty Publications
Glycation, oxidation, and nonenzymatic browning of protein have all been implicated in the development of diabetic complications. The initial product of glycation of protein, fructoselysine (FL), undergoes further reactions, yielding a complex mixture of browning products, including the fluorescent lysine-arginine cross-link, pentosidine. Alternatively, FL may be cleaved oxidatively to form N(epsilon)-(carboxymethyl)lysine (CML), while glycated hydroxylysine, an amino-acid unique to collagen, may yield N(epsilon)-(carboxymethyl)hydroxylysine (CMhL). We have measured FL, pentosidine, fluorescence (excitation = 328 nm, emission = 378 nm), CML, and CMhL in insoluble skin collagen from 14 insulin-dependent diabetic patients before and after a 4-mo period of intensive therapy to …
Novel Chemical Preparative Route For Semiconducting Mose2 Thin Films, K. C. Mandal, O. Savadogo
Novel Chemical Preparative Route For Semiconducting Mose2 Thin Films, K. C. Mandal, O. Savadogo
Faculty Publications
No abstract provided.