title: Eriocaulon buergerianum extract protects PC12 cells and neurons in zebrafish against 6-hydroxydopamine-induced damage.
abstract: BACKGROUND
  Ericaulon buergerianum (Gujingcao) is an ophthalmic, anti-inflammatory and antimicrobial Chinese medicinal herb. This study aims to investigate the neuroprotective effects of Ericaulon buergerianum ethanol extract (EBE) and to elucidate its underlying action mechanism.
  
  
  METHODS
  The viability of dopaminergic (DA) neuron in zebrafish was examined by anti-tyrosine hydroxylase (TH) immunostaining. The locomotor activity of zebrafish was assessed with a digital video tracking system. The viability and cellular damage of the PC12 cells were determined by MTT and LDH assays respectively. The nuclear morphological changes in apoptotic cells were evaluated with DNA staining by Hoechst 33342 dye. Intracellular nitric oxide (NO) was quantified by DAF-FM diacetate staining. The expression of inducible nitric oxide synthase (iNOS) was determined by Western blot.
  
  
  RESULTS
  EBE inhibited the 6-OHDA-induced decrease in total distance of movement in zebrafish. Pretreatments of EBE (25, 50, 100 and 200 μg/ml) increased the viability of 6-OHDA-damaged PC12 cells in a dose dependent manner. Protection against 6-OHDA-induced nuclear fragmentation and accumulation of apoptotic bodies was also observed in EBE pretreated cells. Anti-oxidative (inhibition of NO production and iNOS expression in PC12 cells in vitro) activities of EBE are related to its neuroprotective effects in 6-OHDA-induced DA neuron damage.
  
  
  CONCLUSIONS
  EBE exhibited significant neuroprotective activities in zebrafish, including recovery of dopaminergic neuron loss caused by 6-OHDA in a dose-dependent manner in vivo, inhibition of 6-OHDA-induced decrease of total distance in movement in zebrafish. The iNOS-NO pathway may be involved.
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Av, Padre Tomás Pereira, Taipa, Macao, China. SimonLee@umac.mo.
authors.forename: Meiwei
authors.initials: M
authors.lastname: Wang
authors.forename: Zaijun
authors.initials: Z
authors.lastname: Zhang
authors.forename: Lorita Chi-Veng
authors.initials: LC
authors.lastname: Cheang
authors.forename: Zhixiu
authors.initials: Z
authors.lastname: Lin
authors.forename: Simon Ming-Yuen
authors.initials: SM
authors.lastname: Lee