Here are a few papers that could be retrieved...
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Ions and amino acid analysis of Cyperus articulatus L. (Cyperaceae) extracts and the effects of the latter on oocytes expressing some receptors
Journal of Ethnopharmacology, Volume 95, Issues 2-3, December 2004, Pages 303-309
E. Ngo Bum, K. Lingenhoehl, A. Rakotonirina, H-R. Olpe, M. Schmutz and S. Rakotonirina
Extracts from rhizomes of Cyperus articulatus L. (Cyperaceae) used in Africa and Amazonia to treat many diseases has been shown to possess sedative and anticonvulsant properties. The aim of this study is to determine the mechanism of action of Cyperus articulatus extracts. In Xenopus oocytes expressing receptors, using electrophysiological measurement, extracts of rhizomes of Cyperus articulatus (300 ìg/ml) inhibited 50% of the EC50 and EC80 of glutamate (1.3 and 2.9 microM, respectively) induced inward current through hNMDAR1A/2A receptors. Extracts induced very small current through rGluR3 receptors. The largest current induced by the extract (30 mg/ml) represents 128% of the EC100 of glutamate induced inward current, through rGluR3 receptors. The excess 28% current could be induced by aspartate and/or glutamate in the extracts. The effect on Xenopus oocytes expressing heteromeric GABABR1b/R2 receptors and rectifying potassium channels (Kir3) is clear. A decoction and water extract of Cyperus articulatus induced a large inward current that represented 71 and 57% (respectively) of the EC100 of gaba (30 ìM) induced inward current. The water extract induced also a large current through rectifying potassium channels (Kir3). Part of the current induced through GABAB receptors could be related to rectifying potassium channels and GABAB site receptors. Cyperus articulatus extracts possessed components that could decrease excitation (NMDA receptor antagonists) and increase inhibition (GABAB receptor agonists) in the central nervous system.
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Protection of NMDA-induced neuronal cell damage by methanol extract of Zizyphi Spinosi Semen in cultured rat cerebellar granule cells
Journal of Ethnopharmacology, Volume 95, Issue 1, November 2004, Pages 39-45
Jeong Hee Park, Hyun Joo Lee, Sang Bum Koh, Ju Yeon Ban and Yeon Hee Seong
Zizypus is one of the herbs widely used in Korea and China due to the CNS calming effect. The present study aims to investigate the effect of the methanol extract of Zizyphi Spinosi Semen (ZSS), the seeds of Zizyphus jujuba Mill var. spinosa, on N-methyl-D-aspartate (NMDA)-induced neurotoxicity in cultured rat cerebellar granule neuron. ZSS, over a concentration range of 0.05–5 ìg/ml, inhibited NMDA (1 mM)-induced neuronal cell death, which was measured by a trypan blue exclusion test and a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay. ZSS (0.5 microg/ml) inhibited glutamate release into medium induced by NMDA (1 mM), which was measured by HPLC. Pretreatment of ZSS (0.5 microg/ml) inhibited NMDA (1 mM)-induced elevation of cytosolic calcium concentration ([Ca2+]c), which was measured by a fluorescent dye, Fura 2-AM, and generation of reactive oxygen species (ROS). These results suggest that ZSS prevents NMDA-induced neuronal cell damage in vitro.
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Celastrus paniculatus seed water soluble extracts protect against glutamate toxicity in neuronal cultures from rat forebrain
Journal of Ethnopharmacology, Volume 93, Issues 2-3, August 2004, Pages 213-219
Praful B. Godkar, Richard K. Gordon, Arippa Ravindran and Bhupendra P. Doctor
Aqueous extracts of Celastrus paniculatus (CP) seed have been reported to improve learning and memory in rats. In addition, these extracts were shown to have antioxidant properties, augmented endogenous antioxidant enzymes, and decreased lipid peroxidation in rat brain. However, water soluble extracts of CP seed (CP-WSE) have not been evaluated for their neuroprotective effects. In the study reported here, we used enriched forebrain primary neuronal cell (FBNC) cultures to study the neuroprotective effects of three CP-WSE extracts (a room temperature, WF; a hot water, HF; and an acid, AF) on glutamate-induced toxicity. FBNC were pre-treated with the CP-WSE and then with glutamate to evaluate the protection afforded against excitatory amino acid-induced toxicity. The criteria for neuroprotection were based on the effects of CP-WSE on a mitochondrial function test following glutamate-induced neurotoxicity. Pre-treatment of neuronal cells with CP-WSE significantly attenuated glutamate-induced neuronal death. To understand the molecular mechanism of action of CP-WSE, we conducted electrophysiological studies using patch–clamp techniques on N-methyl--aspartate (NMDA)-activated whole-cell currents in FBNC. WSE significantly and reversibly inhibited whole-cell currents activated by NMDA. The results suggest that CP-WSE protected neuronal cells against glutamate-induced toxicity by modulating glutamate receptor function.
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Effects of Cyperus articulatus compared to effects of anticonvulsant compounds on the cortical wedge
Journal of Ethnopharmacology, Volume 87, Issue 1, July 2003, Pages 27-34
E. Ngo Bum, A. Rakotonirina, S. V. Rakotonirina and P. Herrling
Cyperus articulatus L. (Cyperaceae) is a plant commonly used in traditional medicine in Africa and Latin America to treat many diseases. The water extract from rhizomes of Cyperus articulatus concentration-dependently reduced spontaneous epileptiform discharges and NMDA-induced depolarisations in the rat cortical wedge preparation at concentrations at which AMPA-induced depolarisations are not affected. The two antiepileptic compounds, valproate and ethosuximide, possessed effect neither on epileptiform discharges nor on AMPA- and NMDA-induced depolarisations. Phenobarbital, pentobarbital and phenythoin inhibited both AMPA- and NMDA-induced depolarisations and spontaneous epileptiform discharges. The effects of Cyperus articulatus were very close to the effect of -CPPene. -CPPene also inhibited spontaneous epileptiform discharges and antagonised NMDA- but not AMPA-induced depolarisations. The extract of Cyperus articulatus could contain components acting as NMDA antagonists.
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Anticonvulsant properties of the methanolic extract of Cyperus articulatus (Cyperaceae)
Journal of Ethnopharmacology, Volume 76, Issue 2, July 2001, Pages 145-150
E. Ngo Bum, M. Schmutz, C. Meyer, A. Rakotonirina, M. Bopelet, C. Portet, A. Jeker, S. V. Rakotonirina, H. R. Olpe and P. Herrling
The methanolic extract of rhizomes of Cyperus articulatus, a plant used in traditional medicine in Africa and Latin America for many diseases, possesses anticonvulsant activity in mice. This extract protected mice against maximal electroshock (MES)- and pentylenetetrazol (PTZ)-induced seizures. It also delayed the onset of seizures induced by isonicotinic acid hydrazide and strongly antagonized N-methyl--aspartate-induced turning behavior. The ED50 for protection against seizures was 306 (154–541) mg/kg intraperitoneally (i.p.) for the PTZ test and 1005 (797–1200) mg/kg i.p. for the MES test. The ED50 of methanolic extract against N-methyl--aspartate-induced turning behavior was 875 (623–1123) mg/kg i.p. C. articulatus L. methanolic extract protected 54% of mice from seizures induced by strychnine at the dose of 1000 mg/kg i.p. but had no or a moderate effect only against picrotoxin- or bicuculline-induced seizures. With these effects, the rhizome of C. articulatus L. possesses anticonvulsant properties in animals that might explain its use as a traditional medicine for epilepsy in Africa.
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Extracts from rhizomes of Cyperus articulatus (Cyperaceae) displace [3H]CGP39653 and [3H]glycine binding from cortical membranes and selectively inhibit NMDA receptor-mediated neurotransmission
Journal of Ethnopharmacology, Volume 54, Issues 2-3, November 1996, Pages 103-111
E. Ngo Bum, C. L. Meier, S. Urwyler, Y. Wang and P. L. Herrling
The marshland plant Cyperus articulatus (Cyperaceae) is commonly used in traditional medicine in Africa and Latin America to treat a wide variety of human diseases ranging from headache to epilepsy. We tested the hypothesis that the purported anti-epileptic effect of this plant might be due to a functional inhibition of excitatory amino acid receptors. One or several component(s) contained in the extracts inhibited the binding of [3H]CGP39653 to the NMDA recognition site and of [3H]glycine to the strychnine-insensitive glycine site of the NMDA receptor complex from rat neocortex. Water extracts from rhizomes of Cyperus articulatus dose-dependently reduced spontaneous epileptiform discharges and NMDA-induced depolarizations in the rat cortical wedge preparation at concentrations at which AMPA-induced depolarizations were not affected. We conclude that the purported beneficial effects of Cyperus articulatus might at least partially be due to inhibition of NMDA-mediated neurotransmission.