Pharmacological evidence for antidementia effect of Choto-san (Gouteng-san), a traditional Kampo medicine.

To clarify the clinical efficacy of one of the traditional medicines in the treatment of patients with vascular dementia, we investigated the pharmacological activities of Choto-san in animal models. Pretreatment with Choto-san (0.75-6.0 g/kg po), a component herb, Chotoko (75-600 mg/kg po), and indole alkaloids and phenolic fractions of Chotoko prevented ischemia-induced impairment of spatial learning behaviour in water maze performance of mice. A single administration of Choto-san (0.5 to 6.0 g/kg po) or Chotoko (Uncaria genus) produced a dose-dependent antihypertensive effect in spontaneously hypertensive rats (SHR) and partly inhibited the induction of the apoplexy in stroke-prone SHR (SHR-SP). Choto-san, Chotoko, and its phenolic constituents, (-)epicatechin and caffeic acid, significantly protected NG108-15 cells from injury induced by H(2)O(2) exposure in vitro and also inhibited lipid peroxidation in the brain homogenate. Indole alkaloids, rhynchophylline and isorhynchophylline (1-100 microM), reversibly reduced N-methyl-D-aspartate (NMDA)-induced current concentration dependently in NMDA receptor-expressed Xenopus oocytes. These results suggest that antidementia effects of Choto-san are due to antihypertensive, free radical scavenging and antiexcitotoxic effects, which are attributed at least partly to phenolic compounds and indole alkaloids contained in Chotoko.

In vitro antiplasmodial activity of antimalarial medicinal plants used in Vietnamese traditional medicine.

Among 42 extracts, prepared from 14 medicinal plants used in Vietnamese traditional medicine to treat malaria, 24 were found to have antiplasmodial activity by inhibiting the growth of the chloroquine-resistant Plasmodium falciparum strain FCR-3 with EC(50) values less than 10 microg/ml. Each medicinal plant possessed at least one active extract. The methanol extract of Coscinium fenestratum had the strongest antiplasmodial activity with EC(50) value of 0.5 microg/ml. Activity-guided fractionation led to identification of berberine as the major active constituent.

Ephedrae herba in Mao-Bushi-Saishin-To inhibits IgE-mediated histamine release and increases cAMP content in RBL-2H3 cells.

Acute effect of Mao-Bushi-Saishin-To (Ma-Huang-Fu-Zi-Xi-Xin-Tang in Chinese: MBS) on histamine release was investigated. The IgE-mediated anaphylaxic response in Wistar rats was significantly suppressed by MBS and Mao. However, Saishin and Bushi had no or little effect on the antigen-mediated anaphylaxic reaction. Mao as well as MBS but not Saishin nor Bushi inhibited IgE-mediated histamine release from rat basophilic leukemia (RBL-2H3) cells. Consistently, MBS and Mao but not Bushi nor Saishin increased cAMP levels in RBL-2H3 cells. However, ephedrine, methylephedrine, and pseudoephedrine, the main components in Mao, did not affect histamine release. From these results, increase of cAMP levels may account for the inhibitory effect of Mao on histamine release. Furthermore, these inhibitory actions of MBS were mainly due to Mao with an ingredient(s) different from ephedrines.

Wild ginseng grows in Myanmar.

Ginseng, the underground parts of plants of Panax species, has been used in oriental traditional medicine for centuries. Unfortunately, because of extensive exploitation over thousands of years, the natural source of these species has been almost exhausted. Recently, we have found a wild ginseng growing in Myanmar. Here, by a combination of chemical composition study and gene sequence analysis, we unambiguously demonstrate that the wild ginseng is actually P. zingiberensis, commonly known as ginger ginseng. This ginseng was an indigenous to the southwestern China. However, now it is seriously threatened to brink of extinction and is put on the highest level of protection in China. Therefore, an appropriate protection measure is highly recommended to preserve this valuable resource, since this Myanmar ginseng might turn out to be the last P. zingiberensis, which could ever be seen in the planet.