title: Fisetin lowers methylglyoxal dependent protein glycation and limits the complications of diabetes.
abstract: The elevated glycation of macromolecules by the reactive dicarbonyl and α-oxoaldehyde methylglyoxal (MG) has been associated with diabetes and its complications. We have identified a rare flavone, fisetin, which increases the level and activity of glyoxalase 1, the enzyme required for the removal of MG, as well as the synthesis of its essential co-factor, glutathione. It is shown that fisetin reduces two major complications of diabetes in Akita mice, a model of type 1 diabetes. Although fisetin had no effect on the elevation of blood sugar, it reduced kidney hypertrophy and albuminuria and maintained normal levels of locomotion in the open field test. This correlated with a reduction in proteins glycated by MG in the blood, kidney and brain of fisetin-treated animals along with an increase in glyoxalase 1 enzyme activity and an elevation in the expression of the rate-limiting enzyme for the synthesis of glutathione, a co-factor for glyoxalase 1. The expression of the receptor for advanced glycation end products (RAGE), serum amyloid A and serum C-reactive protein, markers of protein oxidation, glycation and inflammation, were also increased in diabetic Akita mice and reduced by fisetin. It is concluded that fisetin lowers the elevation of MG-protein glycation that is associated with diabetes and ameliorates multiple complications of the disease. Therefore, fisetin or a synthetic derivative may have potential therapeutic use for the treatment of diabetic complications.
authors: Cellular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America. pmaher@salk.edu
authors: Pamela
authors: P
authors: Maher
authors: Richard
authors: R
authors: Dargusch
authors: Jennifer L
authors: JL
authors: Ehren
authors: Shinichi
authors: S
authors: Okada
authors: Kumar
authors: K
authors: Sharma
authors: David
authors: D
authors: Schubert
mesh_terms: D000818:Animals; D001007:Anxiety / Q000188:drug therapy; D002460:Cell Line; D048909:Diabetes Complications / Q000517:prevention & control*; D003920:Diabetes Mellitus / Q000188:drug therapy* / Q000378:metabolism; D005419:Flavonoids / Q000627:therapeutic use*; D044948:Flavonols; D006031:Glycosylation / Q000187:drug effects*; D051379:Mice; D008810:Mice, Inbred C57BL; D011765:Pyruvaldehyde / Q000378:metabolism*; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic / Q000378:metabolism; D000685:Serum Amyloid A Protein / Q000378:metabolism
chemical_list: D005419:Flavonoids; D044948:Flavonols; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic; D000685:Serum Amyloid A Protein; D011765:Pyruvaldehyde; C017875:fisetin