SHIMADA Hiromi Kyoto Pharmaceutical University, Assistant, 薬学部, 助手 (90268102)
MURAKAMI Toshiyuki Kyoto Pharmaceutical University, Assistant, 薬学部, 助手 (40278445)
YOSHIKAWA Masayuki Kyoto Pharmaceutical University, Professor, 薬学部, 教授 (90116129)
|Budget Amount *help
¥3,100,000 (Direct Cost : ¥3,100,000)
Fiscal Year 1998 : ¥800,000 (Direct Cost : ¥800,000)
Fiscal Year 1997 : ¥2,300,000 (Direct Cost : ¥2,300,000)
The effects of various Japanese and Chinese herbal medicines on glucose absorption, allergy, immune responses. and hepatic injury were examined.
From the the leaves of Gymnema sylvestre, gimnemosides a-f were isolated and their structures were determined on the basis of chemical and physicochemical evidence. These saponins inhibited both increase of blood glucose levels in oral glucose-loaded rats and glucose uptake at small intestinal brush borders. Several oleanolic acid glycosides potently inhibited the increased blood glucose levels in oral glucose-loaded rats. To clarify the structural requirements of oleanolic acid glycosides, we examined the inhibitory activity of various oleanolic acid glycosides isolated from Momordica cochinchinensis, Kochia scoparia, Panax japonicus, etc. The results revealed that the 3-O-monodesmoside and 28-carboxy group are essential for such activity. Furthermore, investigation of the action mechanism revealed that they inhibit gastric emptying and glucos
e absorption at small intestinal brush borders, and that capsaicin-sensitive sensory nerves, the sympathetic nervous system, the central nervous systems, and central dopamine2 receptors are involved in the inhibition of gastric emptying.
Sandosaponins A and B with potent histamine release inhibitory activity were isolated from kidney bean (Phaseolus vulgaris). Labolabosides A-F from hyacinth bean (Dolichos lablab), jujubosides from Zizyphi Spinosi Semen (Zizyphus jujuba var. spinosa), and soyasaponins from several beans found to show adjuvant-like activity in mice. The chemical structures of twelve new saponines (escins and isolescins), isolated from horse chestnuts (Aesculus hippocatanum), were determined. Escins Ia-IIb, found to show antiinfiammatory effects in rats and mice As concerns their hypoglycemic activities, it was revealed that their action mechanisms are similar to those of oleanolic acid glycosides,
The chemical structures of qunquenosides I-III from American ginseng (Panax quiquefoliwn), and bupleurosides I-XIII and scorzonerosides A*C with hepatoprotective activity from Chinese Bupleuri Radix (Bupleurum scorzonerifolium) were determined. Strucural requirements of bupleurosides for hepatoprotective activity were clarified.