title: Tuning a 96-well microtiter plate fluorescence-based assay to identify AGE inhibitors in crude plant extracts.
abstract: Advanced glycation end-products (AGEs) are involved in the pathogenesis of numerous diseases. Among them, cellular accumulation of AGEs contributes to vascular complications in diabetes. Besides using drugs to lower blood sugar, a balanced diet and the intake of herbal products potentially limiting AGE formation could be considered beneficial for patients' health. The current paper presents a simple and cheap high-throughput screening (HTS) assay based on AGE fluorescence and suitable for plant extract screening. We have already implemented an HTS assay based on vesperlysines-like fluorescing AGEs quickly (24 h) formed from BSA and ribose under physiological conditions. However, interference was noted when fluorescent compounds and/or complex mixtures were tested. To overcome these problems and apply this HTS assay to plant extracts, we developed a technique for systematic quantification of both vesperlysines (λ(exc) 370 nm; λ(em) 440 nm) and pentosidine-like (λ(exc) 335 nm; λ(em) 385 nm) AGEs. In a batch of medicinal and food plant extracts, hits were selected as soon as fluorescence decreased under a fixed threshold for at least one wavelength. Hits revealed during this study appeared to contain well-known and powerful anti-AGE substances, thus demonstrating the suitability of this assay for screening crude extracts (0.1 mg/mL). Finally, quercetin was found to be a more powerful reference compound than aminoguanidine in such assay.
authors.affiliation: EA 921 SONAS, Université d'Angers, SFR QUASAV 4207, Angers 49045, France. severine.derbre@univ-angers.fr.
authors.forename: Luc
authors.initials: L
authors.lastname: Séro
authors.forename: Lionel
authors.initials: L
authors.lastname: Sanguinet
authors.forename: Patricia
authors.initials: P
authors.lastname: Blanchard
authors.forename: Bach Tai
authors.initials: BT
authors.lastname: Dang
authors.forename: Sylvie
authors.initials: S
authors.lastname: Morel
authors.forename: Pascal
authors.initials: P
authors.lastname: Richomme
authors.forename: Denis
authors.initials: D
authors.lastname: Séraphin
authors.forename: Séverine
authors.initials: S
authors.lastname: Derbré
mesh_terms: D001120:Arginine / Q000031:analogs & derivatives / Q000032:analysis; D005453:Fluorescence; D017127:Glycation End Products, Advanced / Q000032:analysis*; D008239:Lysine / Q000031:analogs & derivatives / Q000032:analysis; D010936:Plant Extracts / Q000737:chemistry*
chemical_list: D017127:Glycation End Products, Advanced; D010936:Plant Extracts; D001120:Arginine; C062187:pentosidine; D008239:Lysine