Neuroprotective effects of ginseng saponins against L-type Ca2+ channel-mediated cell death in rat cortical neurons.
In the present study, we have examined any possible involvement of L-type Ca(2+) channels in ginseng-mediated neuroprotective actions. Exposure to a 50mM KCl (high-K) produced neuronal cell death, which was blocked by a selective L-type Ca(2+) channel blocker in cultured cortical neurons. When cultured cells were co-treated with ginseng total saponin (GTS) and high-K, GTS reduced high-K-induced neuronal death. Using Ca(2+) imaging techniques, we found that GTS inhibited high-K-mediated acute and long-term [Ca(2+)](i) changes. These GTS-mediated [Ca(2+)](i) changes were diminished by nifedipine. Furthermore, GTS-mediated effects were also diminished by a saturating concentration of Bay K (10muM). After confirming the protective effect of GTS using a TUNEL assay, we found that ginsenosides Rf and Rg(3) are active components in ginseng-mediated neuroprotection. These results suggest that inhibition of L-type Ca(2+) channels by ginseng could be one of the mechanisms for ginseng-mediated neuroprotection in cultured rat cortical neurons.
Kim
Sunoh
S
Life Sciences Division, Korea Institute of Science and Technology, 39-1 Hawholgok-dong Sungbuk-gu, Seoul 136-791, Republic of Korea.
Nah
Seung-Yeol
SY
Rhim
Hyewhon
H
D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D020746:Calcium Channels, L-Type / Q000187:drug effects*; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology / Q000187:drug effects*; D036145:Ginsenosides / Q000494:pharmacology*; D009474:Neurons / Q000187:drug effects; D018696:Neuroprotective Agents / Q000494:pharmacology; D005894:Panax / Q000737:chemistry*; D011189:Potassium Chloride / Q000633:toxicity; D051381:Rats; D017207:Rats, Sprague-Dawley; D012503:Saponins / Q000302:isolation & purification / Q000494:pharmacology
D002121:Calcium Channel Blockers; D020746:Calcium Channels, L-Type; D036145:Ginsenosides; D018696:Neuroprotective Agents; D012503:Saponins; C097367:ginsenoside Rg3; D011189:Potassium Chloride; D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester; C055328:ginsenoside Rf