title: Inhibition of VHR dual-specificity protein tyrosine phosphatase activity by flavonoids isolated from Scutellaria baicalensis: structure-activity relationships.
abstract: Three flavonoids: norwogonin, dihydronorwogonin and baicalein, were isolated from the roots of Scutellaria baicalensis, as potential inhibitors of VHR dual-specificity protein tyrosine phosphatase (DS-PTPase). Norwogonin (IC 50 = 1.1 microM), dihydronorwogonin (IC 50 = 2.9 microM) and baicalein (IC 50 = 2.4 microM) showed potent inhibitory activity toward VHR, but had no inhibitory activity against T-cell protein tyrosine phosphatase or serine/threonine protein phosphatase 1. From comparisons to the inhibitory activities of other similar flavonoids, it could be suggested that the presence of a hydroxy group in the B ring of flavonoids interferes with the inhibitory activity toward VHR DS-PTPase.
authors.affiliation: Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, South Korea.
authors.forename: Myung Sun
authors.initials: MS
authors.lastname: Lee
authors.forename: Won Keun
authors.initials: WK
authors.lastname: Oh
authors.forename: Bo Yeon
authors.initials: BY
authors.lastname: Kim
authors.forename: Soon Cheol
authors.initials: SC
authors.lastname: Ahn
authors.forename: Dae Ook
authors.initials: DO
authors.lastname: Kang
authors.forename: Cheon Bae
authors.initials: CB
authors.lastname: Sohn
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Osada
authors.forename: Jong Seog
authors.initials: JS
authors.lastname: Ahn
mesh_terms: D004305:Dose-Response Relationship, Drug; D054640:Dual Specificity Phosphatase 3; D044950:Flavanones; D047309:Flavones; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D015394:Molecular Structure; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors; D008517:Phytotherapy; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D018517:Plant Roots / Q000737:chemistry; D054645:Protein Phosphatase 1; D017027:Protein Tyrosine Phosphatases / Q000037:antagonists & inhibitors*; D031364:Scutellaria baicalensis; D013329:Structure-Activity Relationship
chemical_list: D044950:Flavanones; D047309:Flavones; D005419:Flavonoids; D010936:Plant Extracts; C472146:dihydronorwagonin; C055505:norwogonin; C006680:baicalein; D010749:Phosphoprotein Phosphatases; D054645:Protein Phosphatase 1; D054640:Dual Specificity Phosphatase 3; D017027:Protein Tyrosine Phosphatases