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.
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.
Ban
Ju Yeon
JY
College of Veterinary Medicine and Research Institute of Herbal Medicine, Chungbuk National University, Cheongju, Chungbuk 361-763, South Korea.
Jeon
So-Young
SY
Bae
KiWhan
K
Song
Kyung-Sik
KS
Seong
Yeon Hee
YH
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*
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