title: A fluorogenic assay for methylglyoxal.
abstract: MG (methylglyoxal) is a potent glycating agent and an endogenous reactive dicarbonyl metabolite formed in all live cells and organisms. It is an important precursor of AGEs (advanced glycation end-products) and is implicated in aging and disease. MG is assayed by derivatization by 1,2-diaminobenzene derivatives in cell extracts. Such assays are not applicable to high sample throughput, subcellular, live-cell and in vivo estimations. The use of fluorogenic probes designed for NO (nitric oxide) detection in biological samples and living cells has inadvertently provided probes for the detection of dicarbonyls such as MG. We describe the application of DAF-2 (4,5-diaminofluorescein) and DAR-1 (4,5-diaminorhodamine) for the detection of MG in cell-free systems and application for high-throughput assay of glyoxalase activity and assay of glucose degradation products in peritoneal dialysis fluids. DAF-2 and DAR-1, as for related BODIPY probes, do not have sufficient sensitivity to detect MG in live cells. Care will also be required to control for NO and dehydroascorbate co-detection and interference from peroxidase catalysing the degradation of probes to MG and glyoxal. Fluorogenic detection of MG, however, has great potential to facilitate the assay of MG and to advance towards that capability of imaging this product in live cells in vitro and small animals in vivo.
authors.affiliation: *Clinical Sciences Research Laboratories, Warwick Medical School, University of Warwick, University Hospital, Coventry CV2 2DX, U.K.
authors.forename: Fozia
authors.initials: F
authors.lastname: Shaheen
authors.affiliation: *Clinical Sciences Research Laboratories, Warwick Medical School, University of Warwick, University Hospital, Coventry CV2 2DX, U.K.
authors.forename: Anatoly
authors.initials: A
authors.lastname: Shmygol
authors.affiliation: *Clinical Sciences Research Laboratories, Warwick Medical School, University of Warwick, University Hospital, Coventry CV2 2DX, U.K.
authors.forename: Naila
authors.initials: N
authors.lastname: Rabbani
authors.affiliation: *Clinical Sciences Research Laboratories, Warwick Medical School, University of Warwick, University Hospital, Coventry CV2 2DX, U.K.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Thornalley
mesh_terms: D001681:Biological Assay / Q000379:methods*; D019793:Fluorescein / Q000737:chemistry; D017127:Glycation End Products, Advanced / Q000737:chemistry; D009569:Nitric Oxide / Q000737:chemistry; D011765:Pyruvaldehyde / Q000032:analysis* / Q000737:chemistry
chemical_list: C111205:4,5-diaminofluorescein; D017127:Glycation End Products, Advanced; D009569:Nitric Oxide; D011765:Pyruvaldehyde; D019793:Fluorescein