title: Chemical and biological evaluation of nephrocizin in protecting nerve growth factor-differentiated PC12 cells by 6-hydroxydopamine-induced neurotoxicity.
abstract: The neurotoxin 6-hydroxydopamine (6-OHDA) has been widely used to generate an experimental model of Parkinson's disease. This model is crucial in the search for compounds that diminish 6-OHDA-induced nerve growth factor (NGF)-differentiated PC12 cell death. Nephrocizin (luteolin-7-O-β-D-glucopyranoside), a flavone glycoside, was isolated from widely distributed plants. The protective effects of pre-treatment with nephrocizin on the induced neurotoxicity in PC12 cells by 6-OHDA and its oxidative products, H₂O₂-, and p-quinone, were evaluated herein. Nephrocizin promoted cell viability, scavenged ROS-related products, increased cellular glutathione (GSH) levels, and reduced caspase-3 and -8 activities in 6-OHDA-, H₂O₂-, or p-quinone-treated PC12 cells. Furthermore, nephrocizin-conjugated metabolites in PC12 cells were identified with the boronate-affinity method and LC-MS technology, and preferential regioselectivity at the C2' and C5' positions by the nephrocizin-GSH (or NAC) adduct method was observed. These lines of evidence established that nephrocizin could form a dimer to diminish the intracellular ROS. These results demonstrate the first neuroprotective mechanism of nephrocizin against 6-OHDA-, H₂O₂- or p-quinone-induced cytotoxicity in PC12 cells via chemical and biological studies. These dietary antioxidants are potential candidates for use in intervention in neurodegenerative diseases.
authors.affiliation: School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei 110, Taiwan, ROC.
authors.forename: Yi-Pei
authors.initials: YP
authors.lastname: Lin
authors.forename: Tai-Yuan
authors.initials: TY
authors.lastname: Chen
authors.forename: Hsiang-Wen
authors.initials: HW
authors.lastname: Tseng
authors.forename: Mei-Hsien
authors.initials: MH
authors.lastname: Lee
authors.forename: Shui-Tein
authors.initials: ST
authors.lastname: Chen
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005960:Glucosides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D047311:Luteolin / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D015394:Molecular Structure; D009414:Nerve Growth Factors / Q000378:metabolism*; D018696:Neuroprotective Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D016627:Oxidopamine / Q000031:analogs & derivatives / Q000494:pharmacology*; D016716:PC12 Cells; D051381:Rats; D013329:Structure-Activity Relationship
chemical_list: D005960:Glucosides; D009414:Nerve Growth Factors; D018696:Neuroprotective Agents; D016627:Oxidopamine; C066408:luteolin-7-glucoside; D047311:Luteolin