A review of traditional Japanese medicines and their potential mechanism of action.
Traditional Japanese herbal, or Kampo medicine was developed and modified from Chinese herbal medicine. After the Japanese government approved Kampo for clinical use, much attention has been paid to establishing scientific evidence for the effectiveness of these medicines. Recent progress has been made in elucidating the mechanisms of action of some types of Kampo medicine, including rikkunshito (RKT), daikenchuto, and yokukansan. In this review, we focused on identifying the target molecules and the active ingredients of RKT. Thus far, many target molecules have been implicated in the mechanism of action of Kampo medicines, such as ion channels, enzymes, and receptors. In particular, G protein-coupled receptors are attractive candidates for explaining herbal medicine activity. This is particularly true of RKT, which is composed of 8 independent, crude drug extracts. Recent reports have shown that RKT elicits its effects through dual action to the G protein-coupled receptors: inhibition of serotonergic 5-HT2C and 5-HT2B receptors and activation of ghrelin receptors via specific ingredients of RKT. In addition, we suggest that the identification of the effective ingredients from Kampo medicines could contribute to the discovery and development of new drugs by means of modern high-throughput drug screening technology.
Division of Cancer Pathophysiology, National Cancer Center Research Institute, 1-1, Tsukiji 5-chome, Chuo-ku, Tokyo 104-0045, Japan. yuezono@ncc.go.jp
Yasuhito
Y
Uezono
Kanako
K
Miyano
Yuka
Y
Sudo
Masami
M
Suzuki
Seiji
S
Shiraishi
Kiyoshi
K
Terawaki
D000818:Animals; D004365:Drugs, Chinese Herbal / Q000494:pharmacology / Q000627:therapeutic use; D054768:G-Protein-Coupled Receptor Kinases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D054439:Ghrelin / Q000819:agonists / Q000378:metabolism; D006801:Humans; D020835:Medicine, Kampo; D005894:Panax; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use; D028321:Plant Preparations / Q000494:pharmacology* / Q000627:therapeutic use; D047428:Protein Kinase Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D054440:Receptors, Ghrelin / Q000819:agonists / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D032106:Zanthoxylum; D030521:Zingiberaceae
D004365:Drugs, Chinese Herbal; C515349:GHRL protein, human; D054439:Ghrelin; D010936:Plant Extracts; D028321:Plant Preparations; D047428:Protein Kinase Inhibitors; D054440:Receptors, Ghrelin; C524644:Yi-Gan San; C121414:dai-kenchu-to; C084136:liu-jun-zi-tang; D054768:G-Protein-Coupled Receptor Kinases