title: Protective effect of theaflavins on neuron against 6-hydroxydopamine-induced apoptosis in SH-SY5Y cells.
abstract: Theaflavins, the oxidation products of tea polyphenols are important biologically active components of black tea. 6-hydroxydopamine is a pro-parkinsonian neurotoxin. Theaflavins could inhibit the auto-oxidation of 6-hydroxydopamine in a dose-dependent manner from 0.5 µg/ml to 25 µg/ml. Here we investigated the protective effect of theaflavins on 6-hydroxydopamine induced SH-SY5Y cells against apoptosis (within this concentration range). It was found that pretreating SH-SY5Y cells with 0.5 µg/ml of theaflavins prevented 6-hydroxydopamine-induced loss of cell viability, condensed nuclear morphology, attenuated 6-hydroxydopamine-induced apoptosis, decrease of mitochondrial membrane potential and the increase of intracellular nitric oxide levels. Our results indicated that theaflavins had protective effect against 6-hydroxydopamine induced apoptosis at low concentrations, possibly through inhibition of reactive oxygen species and nitric oxide production.
authors.affiliation: Zhejiang University Tea Research Institute, 268 Kaixuan Road, Hangzhou 310029, P.R. China.
authors.forename: Zihua
authors.initials: Z
authors.lastname: Luo
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhao
authors.forename: Yuefei
authors.initials: Y
authors.lastname: Wang
authors.forename: Xianqiang
authors.initials: X
authors.lastname: Yang
authors.forename: Baolu
authors.initials: B
authors.lastname: Zhao