Ginsenoside-Rd attenuates TRPM7 and ASIC1a but promotes ASIC2a expression in rats after focal cerebral ischemia.
Our previous studies have showed that ginsenoside (GS)-Rd, a mono-compound isolated from traditional Chinese herb panax ginseng, has the neuroprotective effects following ischemic stroke. However, the underlying mechanisms are still largely unknown. Our latest study showed that GS-Rd could block calcium influx in cultured cortical neurons after excitotoxic injury, indicating that GS-Rd may act on cation channels. To explore this possibility, in this study, we used a rat middle cerebral artery occlusion (MCAO) model to examine the effects of GS-Rd on the expression of non-selective cation channels, including transient receptor potential melastatin (TRPM) and acid sensing ion channels (ASIC), and cation channels, including N-methyl-D-aspartate (NMDA) receptors, which all play essential roles in ischemic stroke. Our results showed that both TRPM and ASIC channels were expressed in the brain. At 24 h following MCAO insult, mRNA and protein expression levels of TRPM7, ASIC1a and ASIC2a were significantly increased. Pretreatment of 10 mg/kg GS-Rd attenuated MCAO-induced expression of TRPM7 and ASIC1a but promoted that of ASIC2a. In contrast, GS-Rd had no significant effects on the expression of NMDA receptors. Thus, our results suggest that GS-Rd neuroprotection following cerebral ischemia may be at least due to its effects on the expression of TRPM7, ASIC1a and ASIC2a.
Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China. halo712@live.cn
Yunxia
Y
Zhang
Linfu
L
Zhou
Xiao
X
Zhang
Jiuxu
J
Bai
Ming
M
Shi
Gang
G
Zhao
D062565:Acid Sensing Ion Channels / Q000096:biosynthesis*; D000818:Animals; D015153:Blotting, Western; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D004195:Disease Models, Animal; D036145:Ginsenosides / Q000494:pharmacology*; D020244:Infarction, Middle Cerebral Artery / Q000378:metabolism*; D008297:Male; D018696:Neuroprotective Agents / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D050053:TRPM Cation Channels / Q000096:biosynthesis*
D062565:Acid Sensing Ion Channels; C568268:Asic1 protein, rat; D036145:Ginsenosides; D018696:Neuroprotective Agents; D050053:TRPM Cation Channels; C486584:Trpm7 protein, rat; C049863:ginsenoside Rd