Antioxidative effects of Choi-oki-to and its ability to inhibit the progression of atheroma in KHC rabbits.

Agents which inhibit the oxidative modification of low density lipoprotein (LDL) have been thought to be helpful in preventing the formation of atherosclerotic lesions; the so called "oxidation hypothesis". To test this hypothesis, we examined the antioxidative activities of 127 Kampo medicines in vitro and their inhibitory effects on the development of atheromatous plaque formation in KHC rabbits, a model of spontaneous familial hypercholesterolemia. Some of the 127 Kampo medicines showed scavenging or antioxidative effects equal to or stronger than those of probucol in vitro. Choi joki to, which had the strongest antioxidative effects on LDL in vitro, was chosen for a study in vivo. After 24 weeks, 1 g/kg of Choi joki to successfully inhibited the progression of atherosclerotic lesions in KHC rabbits (P < 0.01). Further investigations regarding the antioxidative effects of Kampo medicines are expected.

Effects of San'o-shashin-to on the antioxidative mechanism in spontaneous familial hypercholesterolaemic rabbits.

We investigated the effects of the Kampo medicine San'o-shashin-to which showed strong antioxidative effects in vitro on antioxidative mechanism in Kurosawa and Kusanagi- hypercholesterolaemic (KHC) rabbits, which are a good model of spontaneous familial hypercholesterolaemia. A 1-g kg(-1)dose of San'o-shashin-to was administered orally for 24 weeks and changes in plasma lipids, low-density lipoprotein (LDL) oxidation and redox dynamics of alpha-tocopherol in plasma and erythrocyte membrane were measured in a control group and San'o-shashin-to-treated group. A significant prolongation of the lag time was found in the 12th and 24th week of the experiment in San'o-shashin-to-treated group, indicating antioxidative effects on LDL. At the end of the administration period, the alpha-tocopherolquinone/alpha-tocopherol ratio in erythrocyte membrane, which reflects the utilization rate of alpha-tocopherol was significantly higher in San'o-shashin-to-treated group. There were no significant differences in the two groups with regards to plasma lipids. These results indicate that San'o-shashin-to had antioxidative effects on LDL in vivo and beneficial effects on redox dynamics of alpha-tocopherol, which is the strongest endogenous antioxidant.

Anti-inflammatory effects of mao-bushi-saishin-to in mice and rats.

Effects of Mao-Bushi-Saishin-to (MBS) on anti-inflammatory activities were examined in mice and rats. MBS significantly inhibited the increase in vascular permeability induced by acetic acid, the ear edema induced by arachidonic acid and phorbol ester, and the cutaneous extravasation induced by bradykinin and histamine. MBS, however, was not effective against the serotonin-induced cutaneous permeability increase in mice. MBS significantly inhibited carrageenin-induced hind foot edema and cotton pellet-induced granulation tissue growth in rats. These results show that MBS may exert anti-inflammatory effects through the underlying mechanism(s) of preventing mediator release from mast cells and macrophages.

Inhibitory effects of Dai-saiko-to (Da-Chai-Hu-Tang) on the progression of atherosclerotic lesions in Kurosawa and Kusanagi-hypercholesterolemic rabbits.

The inhibitory effects of the traditional herbal medicine Dai-saiko-to (Da-Chai-Hu-Tang) on the progression of the atherosclerotic lesions were studied using the spontaneous familial hypercholesterolemia (FH) model, Kurosawa and Kusanagi-hypercholesterolemic (KHC) rabbits. Changes in blood chemistry, pathology and low-density lipoprotein (LDL) oxidation were measured in a control group and a Dai-saiko-to-treated group. In the control group, the area of atheromatous plaques of the aorta progressed between week 12 (29.1%) and 26 (51.5%). This progression of atherosclerotic lesions did not happen in the Dai-saiko-to-treated group between week 12 (26%) and 26 (27.4%). Antioxidative effects on LDL were seen in the Dai-saiko-to-treated group in weeks 16 and 18. Dai-saiko-to did not improve the hypercholesterolemia in the KHC rabbits. These results suggest that Dai-saiko-to has inhibitory effects on the development of atheromatous plaque formation in spontaneous FH model rabbits. It is possible that the antioxidative effects of Dai-saiko-to on LDL led to the beneficial effects observed in this study.

[Protective effects of the Chinese medicine Juzentaiho-to from the adverse effects of mitomycin C and cisplatin].

Some Chinese medicines in Japan have been reported to have not only antitumour effects, but also to offer protection from the adverse effects of anti-tumour agents. However, there is controversy regarding the protective effects of such Chinese medicines against the adverse effects of anti-tumour agents, in this study, we examined the effects of Tsumura Juzentaiho-to (TJ-48) on the toxicity of mitomycin C (MMC) and cisplatin (CDDP). Both the pre-administration of TJ-48 a single time and for seven days shifted the dose response curve and LD50S of MMC and CDDP to the right. Seven days of treatment using TJ-48 delayed deaths due to lethal dose of MMC or CDDP and markedly changed their survival curves. Also, TJ-48 reduced the atrophy of the testis, thymus and spleen caused by MMC. TJ-48 also had beneficial effects on leukopenia, anemia and body weight loss caused by MMC, and increase of BUN and creatinine caused by CDDP. These results indicate that the combined use of TJ-48 may be a new way to in prevent or minimize the toxicity of MMC or CDDP.