Dibenzocyclooctadiene lignans from schisandra chinensis protect primary cultures of rat cortical cells from glutamate-induced toxicity

Mertens-Talcott SU, Talcott ST, Percival SS.
Courtesy of; Kim SR, Lee MK, Koo KA, Kim SH, Sung SH, Lee NG, Markelonis GJ, Oh TH, Yang JH, Kim YC.
J Neurosci Res. 2004 May 1;76(3):397-405.

A methanolic extract of dried schisandra fruit (schisandra chinensis Baill.; schisandraceae) significantly attenuated the neurotoxicity induced by L-glutamate in primary cultures of rat cortical cells. Five dibenzocyclooctadiene lignans (deoxyschisandrin, gomisin N, gomisin A, schisandrin, and wuweizisu C) were isolated from the methanolic extract; their protective effects against glutamate-induced neurotoxicity were then evaluated. Among the five lignans, deoxyschisandrin, gomisin N, and wuweizisu C significantly attenuated glutamate-induced neurotoxicity as measured by:
1). an inhibition in the increase of intracellular [Ca(2+)];
2). an improvement in the glutathione defense system, the level of glutathione, and the activity of glutathione peroxidase; and
3). an inhibition in the formation of cellular peroxide. These results suggest that dibenzocyclooctadiene lignans from Schisandra chinensis may possess therapeutic potential against oxidative neuronal damage induced by excitotoxin.

Shidoji Y, Ogawa H.
J Lipid Res. 2004 Jun;45(6):1092-103

Geranylgeranoic acid (GGA; all-trans 3,7,11,15-tetramethyl-2,6,10,14-hexadecatetraenoic acid) has been shown to induce apoptosis in a human hepatoma-derived cell line, HuH-7. We aimed not only to confirm the apoptogenic properties of GGA and its derivatives, but also to search for natural GGA in medicinal herbs. GGA induced apoptosis in human hepatoma-derived cell lines, HuH-7, PLC/PRF-5, and mouse transformed hepatocyte-derived cell line, MLE-10, in a dose- and time-dependent manner, but failed to induce cell death in human hepatoblastoma-derived HepG-2 and mouse primary hepatocytes in the same condition. Besides GGA, 4,5-didehydro GGA, 14,15-dihydro GGA, and 2,3-dihydro GGA were also active to induce cell death in HuH-7 cells, while 4,5-didehydro-10,11, 14,15-tetrahydro GGA, 4,5,8,9-tetrahydro GGA, farnesoic acid, and geranylgeraniol were inert. By using liquid chromatography/mass spectrometry, we found natural GGA as a negative ion of m/z 303.4 in a Chinese herb, schisandra chinensis, and schisandra GGA was identified by derivatization with both mild methylation and catalytic hydrogenation. Some other GGAs hydrogenated in the different degrees, including phytanic acid (perhydro GGA), were also found in s. chinensis. GGA and phytanic acid were detected in 24 out of 25 herbs tested. The present study is the first report of natural GGA in medicinal herbs.

Li XN, Cui H, Song YQ, Liang YZ
Yao Xue Xue Bao. 2001 Mar;36(3):215-9

Aim: To detect chemical components of the essential oil of schisandra chinensis.
Methods: The essential oil was analyzed by means of gas chromatography and mass spectrometry (GC/MS), heuristic evolving latent projections (HELP), resolution and overall volume integration method. The HELP method along with the data from GC/MS can be used to conduct the peak purity examination and resolution of overlapping peaks so as to obtain a pure chromatogram and MS spectrum of each component.
Results: Fifty-six components were separated and 49 of them were qualitatively and quantitatively analyzed. All the components represent about 98% of the total content.
Conclusion: The resolved pure chromatogram and MS spectrum can greatly enhance the reliability of similar searches in the commercial MS database and thus contribute to the accuracy of the qualitative and quantitative analysis of the essential oil.