title: Distinct effects of tea catechins on 6-hydroxydopamine-induced apoptosis in PC12 cells.
abstract: Green tea polyphenols have aroused considerable attention in recent years for preventing oxidative stress related diseases including cancer, cardiovascular disease, and degenerative disease. Neurodegenerative diseases are cellular redox status dysfunction related diseases. The present study investigated the different effects of the five main components of green tea polyphenols on 6-hydroxydopamine (6-OHDA)-induced apoptosis in PC12 cells, the in vitro model of Parkinson's disease (PD). When the cells were treated with five catechins respectively for 30 min before exposure to 6-OHDA, (-)-epigallocatechins gallate (EGCG) and (-)-epicatechin gallate (ECG) in 50-200 microM had obvious concentration-dependent protective effects on cell viability, while (-)-epicatechin (EC), (+)-catechin ((+)-C), and (-)-epigallocatechin (EGC) had almost no protective effects. The five catechins also showed the same pattern described above of the different effects against 6-OHDA-induced cell apoptotic characteristics as analyzed by cell viability, fluorescence microscopy, flow cytometry, and DNA fragment electrophoresis methods. The present results indicated that 200 microM EGCG or ECG led to significant inhibition against typical apoptotic characteristics of PC12 cells, while other catechins had little protective effect against 6-OHDA-induced cell death. Therefore, the classified protective effects of the five catechins were in the order ECG> or = EGCG>>EC> or = (+)-C>>EGC. The antiapoptotic activities appear to be structurally related to the 3-gallate group of green tea polyphenols. The present data indicate that EGCG and ECG might be potent neuroprotective agents for PD.
authors.affiliation: Laboratory of Visual Information Processing, Department of Molecular and Cell Biophysics, Institute of Biophysics, Academia Sinica, Beijing 100101, China.
authors.forename: Guangjun
authors.initials: G
authors.lastname: Nie
authors.forename: Chaofang
authors.initials: C
authors.lastname: Jin
authors.forename: Yuanlin
authors.initials: Y
authors.lastname: Cao
authors.forename: Shengrong
authors.initials: S
authors.lastname: Shen
authors.forename: Baolu
authors.initials: B
authors.lastname: Zhao
mesh_terms: D018663:Adrenergic Agents / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis; D001628:Beverages; D002392:Catechin / Q000494:pharmacology*; D002467:Cell Nucleus / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004396:Coloring Agents / Q000494:pharmacology; D053938:DNA Fragmentation; D004305:Dose-Response Relationship, Drug; D004587:Electrophoresis, Agar Gel; D005419:Flavonoids; D005434:Flow Cytometry; D008956:Models, Chemical; D016627:Oxidopamine / Q000494:pharmacology*; D016716:PC12 Cells; D010636:Phenols / Q000627:therapeutic use; D011108:Polymers / Q000627:therapeutic use; D051381:Rats; D013778:Tetrazolium Salts / Q000494:pharmacology; D013844:Thiazoles / Q000494:pharmacology
chemical_list: D018663:Adrenergic Agents; D004396:Coloring Agents; D005419:Flavonoids; D010636:Phenols; D011108:Polymers; D013778:Tetrazolium Salts; D013844:Thiazoles; D016627:Oxidopamine; D002392:Catechin; C022616:thiazolyl blue