As medical science has progressed, the profile of illness has changed greatly : disease related to aging and inappropriate lifestyles is increasing. Because it is difficult to cure patients with these diseases using only modern medicine, Kampo medicine, which tends to regulate homeostasis, has an increasing role in medical practice in Japan. Although Kampo medicines have had a long clinical history to support their efficacies and safety, efficacy of Kampo medicine requires scientific clarification of action mechanism and active ingredients in nonclinical studies and objective clinical evaluations as an evidence-based medicine. Because Kampo medicines contain many active ingredients due to the several component herbs, clarification of such combination effects, and standardization are also very important in order to understand the mechanism of action and supply quality-controlled materials. In this review, our basic approaches on elucidation of action mechanism and active ingredients of Kampo medicines are described.
Orengedokuto (OGT), a traditional Chinese formulation containing four crude drugs (Scutellariae Radix, Coptidis Rhizoma, Phellodendri Cortex and Gardeniae Fructus), has been used for various conditions accompanied with atherosclerotic-related disorders. Oral administration of OGT for 3 days before and 7 days after balloon injury resulted in a dose-dependent attenuation of neointimal formation and vascular smooth muscle cell (VSMC) proliferation in balloon-injured carotid arteries in cholesterol-fed rats. Furthermore, the serum collected from cholesterol-fed rats orally treated with OGT significantly reduced the migration of cultured VSMC. Thus, OGT may attenuate carotid artery neointimal formation following balloon endothelial denudation via inhibition of VSMC proliferation and migration. The inhibitory effects of OGT on neointimal formation were mediated primarily by Scutellariae Radix and Coptidis Rhizoma composed of OGT. The present results suggest that OGT may be promising candidates as preventive agents for atherosclerosis in humans.
Wood creosote pill preparation, in which 4 crude drug powders, Gambir, Phellodendri Cortex, Glycyrrhizae Radix, and Citri Unshiu Pericarpium are compounded, has been used for diarrhea. In the present study, the significance of the compounding of these crude drug powders was examined in castor oil-induced diarrhea model in rats. Oral administration of small wood creosote pill (P4Rx5) exerted anti-diarrheal action for up to 3 hours and intestinal peristaltic motility-suppressive action, which was assessed by charcoal meal test. These suppressive actions were not noted in the groups of the rats receiving wood creosote alone at a dose level (11 mg/kg) that is contained in P4Rx5. From these findings, it was revealed that crude drugs compounded were responsible for the anti-diarrheal and intestinal peristaltic motility-suppressive actions of P4Rx5. Pharmacological actions were examined for variant pills (without one of the crude drug powders), revealing that Citri Unshiu Pericarpium was responsible for retention of the anti-diarrheal effects and the suppression of castor oil-induced intestinal peristaltic motility by P4Rx5. Furthermore, it was found that the compounded crude drug powders increased the AUC of guaiacol (a major anti-diarrheal component of wood creosote), being involved in the intestinal peristaltic motility-suppressive action of P4Rx5. The results obtained in the present study may provide evidence supporting the usefulness of the compounding of the crude drugs in traditional wood creosote pills such as “Seiro-gan”, and give a rationale for development of new preparations compounding wood creosote with crude drug powders.
Recently, by various procedures many researchers had established the fact that medical ginseng (specifically, Korean red ginseng) protects the organism from environmental stresses. Previously, I proposed that the mechanism of anti-stress action of red ginseng depends on keeping homeostasis of the organism, and proved it by basic experiments and clinical investigation. In this study, I aimed to prove the anti stress effect of red ginseng on the stress of organism induced by exercise. So I requested 6 healthy females to perform an exercise test under red ginseng acute dosage. As a result, I found that red ginseng regulates correctly the reaction of cardiovascular system under exercise; it enhances energy efficiency, and also can be considered to protect the organism from stresses by stabilization of autonomic nerve.
Agarwood is one of most valuable minor forest products of tropical Southeast Asia forests. In Vietnam, considered as rich source of high quality product, agarwood is collected from heartwood of Aquilaria crassna (Thymelaeaceae). Continuing the survey of agarwood in Vietnam, it was carried out on plantations at Phu Quoc Island, and information about cultivation of agarwood was gathered from interview with local people. The results showed that cultivation of agarwood by islanders is increasing every year. Local plantations are based on seeds, seedlings and young Aquilaria trees, which grows together with other crops, for a future profit. The promotion and development of agarwood plantations would be an initiative to preserve natural Aquilaria trees, as well as supply the high demand for agarwood in world market.