title: Catechin and epicatechin from Smilacis chinae rhizome protect cultured rat cortical neurons against amyloid beta protein (25-35)-induced neurotoxicity through inhibition of cytosolic calcium elevation.
abstract: We previously reported that the Smilacis chinae rhizome inhibits amyloid beta protein (25-35) (Abeta (25-35))-induced neurotoxicity in cultured rat cortical neurons. Here, we isolated catechin and epicatechin from S. chinae rhizome and also studied their neuroprotective effects on Abeta (25-35)-induced neurotoxicity in cultured rat cortical neurons. Catechin and epicatechin inhibited 10 microM Abeta (25-35)-induced neuronal cell death at a concentration of 10 microM, which was measured by a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and Hoechst 33342 staining. Catechin and epicatechin inhibited 10 microM Abeta (25-35)-induced elevation of cytosolic calcium concentration ([Ca2+]c), which was measured by a fluorescent dye, Fluo-4 AM. Catechin and epicatechin also inhibited glutamate release into medium induced by 10 microM Abeta (25-35), which was measured by HPLC, generation of reactive oxygen species (ROS) and activation of caspase-3. These results suggest that catechin and epicatechin prevent Abeta (25-35)-induced neuronal cell damage by interfering with the increase of [Ca2+]c, and then by inhibiting glutamate release, generation of ROS and caspase-3 activity. Furthermore, these effects of catechin and epicatechin may be associated with the neuroprotective effect of the S. chinae rhizome.
authors.affiliation: College of Veterinary Medicine and Research Institute of Herbal Medicine, Chungbuk National University, Cheongju, Chungbuk 361-763, South Korea.
authors.forename: Ju Yeon
authors.initials: JY
authors.lastname: Ban
authors.forename: So-Young
authors.initials: SY
authors.lastname: Jeon
authors.forename: KiWhan
authors.initials: K
authors.lastname: Bae
authors.forename: Kyung-Sik
authors.initials: KS
authors.lastname: Song
authors.forename: Yeon Hee
authors.initials: YH
authors.lastname: Seong
mesh_terms: D016229:Amyloid beta-Peptides / Q000633:toxicity*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D053148:Caspase 3 / Q000378:metabolism; D002392:Catechin / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005333:Fetus / Q000166:cytology; D018698:Glutamic Acid / Q000378:metabolism; D007473:Ion Channels / Q000378:metabolism; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D018696:Neuroprotective Agents / Q000494:pharmacology*; D010446:Peptide Fragments / Q000633:toxicity*; D010936:Plant Extracts / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism; D027343:Rhizome / Q000737:chemistry; D032281:Smilax / Q000737:chemistry*
chemical_list: D016229:Amyloid beta-Peptides; D007473:Ion Channels; D018696:Neuroprotective Agents; D010446:Peptide Fragments; D010936:Plant Extracts; D017382:Reactive Oxygen Species; C074636:amyloid beta-protein (25-35); D018698:Glutamic Acid; D002392:Catechin; D053148:Caspase 3; D002118:Calcium