Wuweizisu C from Schisandra chinensis decreases membrane potential in C6 glioma cells.
OBJECTIVE
To study the effects of dibenzocyclooctadiene lignans isolated from Schisandra chinensis, such as wuweizisu C, gomisin N, gomisin A, and schisandrin, on the membrane potential in C6 glioma cells.


METHODS
The membrane potential was estimated by measuring the fluorescence change in DiBAC-loaded glioma cells.


RESULTS
Wuweizisu C decreased the membrane potential in a concentration-dependent manner. Gomisin N and gomisin A, however, showed differential modulation and no change was induced by schisandrin or dimethyl- 4,4'-dimethoxy-5,6,5',6'-dimethylene dioxybiphenyl-2,2'-dicarboxylate, a synthetic drug derived from dibenzocyclooctadiene lignans. We found no involvement of G(i/o ) proteins, phospholipase C, and extracellular Na(+) on the wuweizisu C-induced decrease of the membrane potential. Wuweizisu C by itself did not change the intracellular Ca(2+)[Ca(2+)](i) concentration, but decreased the ATP-induced Ca(2+) increase in C6 glioma cells. The 4 lignans at all concentrations used in this study did not induce any effect on cell viability. Furthermore, we found a similar decrease of the membrane potential by wuweizisu C in PC12 neuronal cells.


CONCLUSIONS
Our results suggest that the decrease in the membrane potential and the modulation of [Ca(2+)](i) concentration by wuweizisu C could be important action mechanisms of wuweizisu C.
Choi
Young-whan
YW
Department of Horticultural Bioscience, Pusan National University, Miryang-si 627-706, Republic of Korea.
Kim
Kyeok
K
Jo
Ji-yeong
JY
Kim
Hyo-lim
HL
Lee
You-jin
YJ
Shin
Woo-jung
WJ
Sacket
Santosh-J
SJ
Han
Mijin
M
Im
Dong-soon
DS
D000818:Animals; D002118:Calcium / Q000378:metabolism; D045744:Cell Line, Tumor; D034242:Cyclooctanes / Q000494:pharmacology; D005638:Fruit / Q000737:chemistry; D019204:GTP-Binding Proteins / Q000378:metabolism; D005910:Glioma / Q000503:physiopathology; D006801:Humans; D007202:Indicators and Reagents; D017705:Lignans / Q000494:pharmacology*; D008564:Membrane Potentials / Q000187:drug effects*; D016716:PC12 Cells; D011083:Polycyclic Compounds / Q000494:pharmacology*; D051381:Rats; D032141:Schisandra / Q000737:chemistry*; D010738:Type C Phospholipases / Q000378:metabolism
D034242:Cyclooctanes; D007202:Indicators and Reagents; D017705:Lignans; D011083:Polycyclic Compounds; C031409:schizandrin C; D010738:Type C Phospholipases; D019204:GTP-Binding Proteins; D002118:Calcium