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Three Kampo medicines, Boiogito (BOT), Bofutsushosan (BTS) and Orengedokuto (OGT), used for obese patients were investigated for their effects on adipogenesis in cultured rat white adipocytes. Administration of the three extracts suppressed adipogenesis in concentration-dependent manners (1-100 microg/ml) without any cytotoxicity. Changes in mRNA expression levels were analyzed using a Rat 230 2.0 Affymetrix GeneChip microarray system. DNA microarray analysis (total probe set: 31099) using cDNAs prepared from adipocytes revealed that BOT, BTS and OGT increased the expression of 133-150 genes and decreased the expression of 42-110 genes by > or =2-fold. We identified 329 downregulated genes and 189 upregulated genes among a total set of 514 probes (overlap: 4). Overall, genes related to cellular movement, cell death, cell growth/differentiation and immune responses were the most downregulated, while those related to lipid metabolism and cell signaling were the most upregulated. Semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) assays were conducted to confirm the microarray results. Analysis of the clustering profiles of the microarray results revealed that BOT and BTS changed the expression levels of similar genes mainly involved in small molecule biochemistry and cell differentiation, while OGT altered 10 genes related to lipid metabolism, in contrast to the effects of BOT and BTS. We also measured mRNA expression levels of seven selected genes highly contributing to the lipid metabolism by using semiquantitative RT-PCR assay, that were acetyl-Coenzyme A carboxylase alpha (ACACA), AE binding protein 1 (AEBP1), patatin-like phospholipase domain containing 8 (PNPLA8), secretoglobin (SCGB1A1), adrenergic (ADRB3), adiponectin (ADIPOQ), monoglyceride lipase (MGLL). Beta-actin (ACTB) gene was used as an endogenous internal standard. The present findings indicate that these three herbal extracts have the potential to prevent adipogenesis in rat white adipocytes through different mechanisms via modulation of gene expression levels.

From stem bark of Callistemon rigidus (Myrtaceae), piceatannol and scirpusin B were isolated as components that exhibit inhibitory effects on alpha-amylase activity in isolated mouse plasma. In particular, scirpusin B also inhibited alpha-amylase in mouse gastrointestinal tract. Thus, we expect the depressive effect on the elevation of postprandial blood glucose may be a new medicinal use of this compound as well as the plant itself.

The effects of Saiko-ka-ryukotsu-borei-to (SRBT), a Chinese medicinal prescription, on mouse serum amylase activity were investigated in vivo. SRBT was found to not only dose- and/or time-dependently augment amylase activity, but also to increase alpha-amylase protein content and soluble starch metabolic activity. These results provide a rational basis for the clinical use of SRBT that may accompany disease therapy.

Mongolian plants were screened for their influence on alpha-amylase activity in mouse plasma. Methanolic extracts of Geranium pratense, Rhodiola rosea, Ribes pullchelum and Vaccinium uliginosum inhibited the enzyme activity in isolated mouse plasma by greater than 40% and the effect was concentration dependent. Vaccinium uliginosum also showed a depressive effect on elevation of postprandial blood glucose to some extent.

Chinese medicinal prescriptions were screened for their effects on alpha-amylase activity in mouse plasma. Daio-kanzo-to, Hange-koboku-to, Saiko-ka-ryukotsu-borei-to, Saiko-keishi-kankyo-to and Mao-to changed the activity in isolated mouse plasma greatly and concentration dependently. However, no prescription influenced the elevation of postprandial blood glucose.

A tyrosinase inhibitor was isolated from the peel of Citrus fruit by activity-guided fractionation, and identified as 3',4',5,6,7,8-hexamethoxyflavone (nobiletin) by comparison with reported spectral data. Nobiletin (IC50 of; 46.2 microM) exhibited more potency than Kojic acid (IC50; 77.4 microM) used as a positive control, and it was found to be potentially an effective inhibitor of the production of melanin.

In vitro antifungal activities of naphtoquinone-derivatives, which are constituents of Shikon, roots of Lithospermum erythrorhizon, were investigated against several fungal pathogens. When the biological activity of these compounds was tested against fungi, a wide range of sensitivity was recorded. Shikonin was found to have a stronger than fluconazole against yeast-like fungi: four-fold against Candida krusei (minimal inhibitory concentration (MIC); 4 microg/ml) and two-fold (MIC; 4 microg/ml) against Saccharomyces cerevisiae, though it showed the same potency as fluconazole against C. glabrata. Deoxyshikonin also exhibited four-fold stronger activity against C. krusei (MIC; 4 microg/mi) and three-fold (MIC; 2 microg/ml) stronger against S. cerevisiae. Acetylshikonin and beta-hydroxyisovaleryl shikonin showed lower activities against all fungal pathogens except for C. krusei compared with the standard. Against the filamentous fungus, Trichosporon cutaneum, all naphthoquinones were found to have a range of activity with lower potency than standard. This result provides a rational basis for the clinical use of shikon and shows the possibility of its use in medicinal treatment as an anti-inflammatory agent with antifungal activity.

Screening of crude drugs for inhibitory activity on alpha-amylase in mouse plasma was performed. Hot water extracts and ethanolic extracts of Arecae Semen, Ephedrae Herba, Malloti Cortex, Rhei Rhizoma and ethanolic extract of Moutan Cortex inhibited enzyme activity in isolated mouse plasma strongly and dose-dependently. However, the effects of these 9 extracts were not observed in the plasma when they were administered intraperitoneally or orally. Ethanolic extract of Arecae Semen also showed a depressive effect on elevation of postprandial blood glucose.

The effect of Saiko-ka-ryukotsu-borei-to (SRBT) on the stress-induced enhancement of serum corticosterone in various stress models was investigated in mice. The serum corticosterone was elevated significantly by immobilized stress, forced-swim stress, electric-shock stress, psychological stress and conditioned-fear stress, respectively. The concentration in the last two models was decreased in a dose-dependent manner by pre-administration of SRBT (10, 60, 100, 600 and 1000 mg/kg, p.o.). Therefore, this action seems to be effective in stress involving emotional factors but ineffective in physical stress models. These results indicate that the anti-stress effect of SRBT is dependent strongly on the degree of psychological change compared with physical change in mice.