The role of human intestinal bacteria is indispensable for the metabolic activation of phytoestrogenic precursor lignans. This review summarized recent researches on the in vitro intestinal bacteria transformation of lignan precursors, secoisolariciresinol diglucoside (SDG), arctiin, pinoresinol diglucoside (PDG), and their aglycones, to mammalian lignans enterodiol (END) and enterolactone (ENL). The isolation and characterization of several bacteria from human feces, responsible for the related reactions were also described.

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There is a number of reports on the effects of eicosapentaenoic acid (EPA) on tumor growth. Since it is well known that EPA is very unstable, it seems likely that the by-products (EPA derivatives, EPAD) formed from EPA ethylester (an original product) during the accelerated stability test might have lower antitumor activity compared with EPA ethylester. However, the O₂^- production in Lewis lung carcinoma (LLC) cells by EPA ethylester was similar to that in EPAD-treated LLC cells. We obtained two EPA derivatives (E-1 and E-2) as well as EPA ethylester (non-reactive substance), EPA (free form) from EPA ethylester under storage conditions of 60±5% relative humidity at 37°C for 30 days. E-1 and E-2 were identified as EPA ethylester dimer and EPA hydroxyethylester, respectively, by the analysis of the ¹H-NMR and ¹³C-NMR spectra and MS spectrum. The inhibitory effect of E-1 and E-2 on the DNA synthesis in Lewis lung tumor cells was greater than that of EPA ethylester. EPA ethylester, E-1 and E-2 increased the O₂^- production by LLC cells at a concentration of 0.033 to 3.3 g/mL, and the effects of E-1 was stronger than that of EPA ethylester. The inhibitory effects of E-1 and E-2 on Matrigel-induced capillary-like network formation were stronger than the effect of EPA ethylester. These findings suggest that EPA ethylester dimer (E-1) and EPA hydroxyethylester (E-2) formed from EPA ethylester (an original product) by the accelerated stability test may be a candidate compound for antitumor agents as well as the antitumor action of EPA ethylester.

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Kampo medicines are frequently administered to patients with multiple menopausal symptoms as an alternative to hormone replacement therapy (HRT). The level of estrogen-like activity in the medicines, however, had not been clarified. In order to assess the estrogen-like activity, we established a high-sensitivity luciferase reporter gene assay using MCF-7 cells. Twenty-five kinds of Kampo medicines used for the treatment of menopausal syndromes and gynecological diseases were subjected to the assay. All of them except for tokishakuyakusan (TJ-23) showed estrogen-like activity. The estrogen-like activity was corrected with a daily-dose of each of the Kampo medicines to evaluate the dose as β-estradiol (E2) per day. In kakkonto (TJ-1 and OMRC-K1) and kakkonkokato (OMRC-K2) the estrogen-like activities were detected at 1 to 3 μg/day and the activities in other Kampo medicines were under 150 ng/day. Thus, the levels of estrogen-like activities in these Kampo medicines turned out to be lower than the level of HRT (625 μg/day of estrogen). Furthermore, we examined the mechanism of action for kakkonto that showed the highest level of estrogen-like activity. The medicine as well as expressed estrogen-like activity through estrogen receptor and estrogen responsive element. These results indicated that almost all of the Kampo medicines used for patients with multiple menopausal symptoms have estrogen-like activities. However, it is a possibility that the clinical efficacies of the medicines are induced by a different mechanism from HRT, since Kampo medicines showed extremely low levels of estrogen-like activities. Therefore Kampo medicines may be safer than HRT. In order to guarantee the safety of routine and long-term administration of Kampo medicines, further investigations are required, for instance, detecting the blood estrogen level and the growth-promoting effect to hormone-dependent tumors.

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We investigated the effects of keishibukuryogan and tokishakuyakusan, which are representative formulations for overcoming oketsu, on vascular function and expression patterns of plasma proteins in spontaneously diabetic rats. Twenty-one- to 24-week-old male WBN/Kob rats were maintained for 18 weeks on a diabetes-accelerated feed, and received standard (diabetes-accelerating) chow containing 3% (wt/wt) keishibukuryogan or tokishakuyakusan for 25 weeks. There was no significant change in body weight or blood glucose among the groups. Acetylcholine-induced endothelium-dependent relaxation of the keishibukuryogan group significantly increased compared to that of controls. Xanthine/xanthine oxidase-induced contraction of the tokishakuyakusan group and phospholipase A₂-induced contraction of the keishibukuryogan and tokishakuyakusan groups significantly decreased compared to the controls. Transit time of whole blood tended to decrease in the tokishakuyakusan group compared to controls. NO₂^-/NO₃^- in the keishibukuryogan and tokishakuyakusan groups significantly decreased compared to controls. A study using surface enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) demonstrated that five and eight peaks had significantly changed peak intensities in plasma of rats treated with keishibukuryogan and tokishakuyakusan, respectively, as compared to the controls. Thus, two representative formulations for overcoming oketsu with different mechanisms of action had favorable effects against vascular dysfunction. Altered plasma protein levels were commonly observed in the rats administered these two formulations. Our study using ProteinChip technology may be useful for the evaluation of the relationship between the efficacy and the profiling of plasma protein expression after administration Kampo medicines, thus leading to the understanding of “Sho” in Kampo medicine.

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A study of glycyrrhizin metabolism using rat fecal suspensions showed that glycyrrhizin consumption significantly activated glycyrrhizin metabolism, with glycyrrhizin consumption significantly elevating glycyrrhizin metabolism in some rats (responders) but not in others (nonresponders). Since intestinal microflora are believed to be responsible for the difference between responders and nonresponders, an attempt was made to identify those factors associated with the response to glycyrrhizin consumption by investigating the effects of long-term consumption and fasting on glycyrrhizin metabolism. The results showed that long-term glycyrrhizin consumption and fasting caused nonresponder rats to become responders. Since fasting was the most significant factor in the response to glycyrrhizin consumption, fasting appears to be one of the major facilitators of intestinal metabolism of glycyrrhizin. Given that this noninvasive and convenient metabolic study could ascertain the metabolism of prodrugs such as glycyrrhizin, the technique could also be useful for identifying responders to herbal and Chinese medicines. Furthermore, the relationship between the response to glycyrrhizin consumption and pseudoaldosteronism was investigated by comparing urinary potassium and blood pressure, but no significant differences in these parameters were observed between responders and nonresponders.

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Agarwood is one of the most valuable non-timber forest products harvested from the tropical forest in Southeast Asia. We have surveyed agarwood in Indonesia which is performed through interviewed collectors, businessmen, and government officers (Ministry of Forestry, East Kalimantan, Indonesia) and also surveyed the wild agarwood and its cultivation in South Sulawesi and East Kalimantan Provinces. High economic value is one of the reason for collecting agarwood to increase family income of the peoples living near by the forest. Each surveyed area has a different classification and price of each grade, according to their experience by observing the darkness, smell, oily, and density of agarwood. Over exploitation of natural resource of agarwood makes the stock becoming exhausted. It was been an initiative for conservating the plant of source agarwood by cultivation. Fungi, the known stimulators in formation of agarwood, are used in the cultivation of agarwood. Fusarium laseritum is the faster fungus infected of Aquilaria sp. tree, and can be isolated and inoculated easily into medium. Thus, this fungus is used by inoculate into the holes on the trunk. One year after inoculation obtained agarwood with the lowest grade. This cultivation program was supported by Indonesian government through research and training to the collector who cultivate agarwood.

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We conducted the attitude survey in order to investigate medical student's opinion about Kampo medicine among the first- and second-year medical students in 2004 and the second- to fifth-year medical students in 2003. The number of students who answered the questionnaires was 68 in first-year, 58 in second-year of 2003, 39 in second-year of 2004, 72 in third-year, 33 in fourth-year and 23 in fifth-year medical students. As a results, 86.7% of all students possessed a great interested in Kampo medicine. The students expect that Kampo medicine exerts different effectiveness from western medicine. And this expectance would take the interest to Kampo medicine. On the other hand, for 64.1% of the students who answered they had no interest in Kampo medicine, the cause was their own little knowledge. The lectures about Kampo medicine are exerted for fourth-year students in Nara medical university. The 4th year students understand the adverse effects. They also understand that the lectures are needed absolutely in university and the knowledge for Kampo medicine will become more important in future. These results suggest that it is important to continue more lectures to provide adequate knowledge about Kampo medicine for undergraduate students.

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