Furanoid 8-epidiosbulbin E acetate (EEA) is a major constituent of herbal medicine Dioscorea bulbifera L. (DB), a traditional Chinese medicine herb. Our preliminary studies demonstrated that administration of EEA caused acute hepatotoxicity in mice, and the observed toxicity required cytochromes P450-mediated metabolism. Metabolic activation studies of EEA were performed in vitro and in vivo. Microsomal incubations of EEA supplemented with N-acetyl lysine (NAL) and glutathione (GSH) generated six metabolites (M1-M6). M1-M4 were characterized as pyrrole derivatives, and M5 and M6 were pyrrolinones. M2-M6 were detected in bile and/or urine of rats given EEA. Dimethyldioxirane-mediated oxidation of EEA in the presence of NAL and GSH produced M1-M6, all of which were generated in microsomal incubations. The structures of M3 and M6 were confirmed by (1)H and (13)C NMR. These findings provide evidence for the metabolic activation of EEA to the corresponding cis-enedial intermediate both in vitro and in vivo. Ketoconazole inhibited the microsomal production of the cis-enedial, and P450 3A4 was found to be the primary enzyme involved in the bioactivation of EEA.

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Background:The potential mechanism of YHL-14 against cancer cells has not been explored. Results: YHL-14 induces G 2 /M phase arrest and inhibition of cancer cell growth by up-regulation of p21 transcription and protein expression via modulation of Sp1 protein stability. Conclusion: YHL-14 inhibits bladder and colon cancer cell growth through up-regulation of p21 expression. Significance: This study identifies a novel mechanism underlying the anticancer effect of YHL-14.

Since the discovery of penicillin, Penicillium has become one of the most attractive fungal genera for the production of bioactive molecules. Marine-derived Penicillium has provided numerous excellent pharmaceutical leads over the past decades. In this review, we focused on the cytotoxic metabolites * (* Cytotoxic potency was referred to five different levels in this review, extraordinary (IC50/LD50: <1 μM or 0.5 μg/mL); significant (IC50/LD50: 1~10 μM or 0.5~5 μg/mL); moderate (IC50/LD50: 10~30 μM or 5~15 μg/mL); mild (IC50/LD50: 30~50 μM or 15~25 μg/mL); weak (IC50/LD50: 50~100 μM or 25~50 μg/mL). The comparative potencies of positive controls were referred when they were available). produced by marine-derived Penicillium species, and on their cytotoxicity mechanisms, biosyntheses, and chemical syntheses.

Bioassay-guided fractionation of an EtOAc extract of the leaves of Rosa laevigata afforded two new 19-oxo-18,19-seco-ursane-type triterpenes (1 and 3), a new ursane-type nortriterpene (2), a new ursane-type triterpene lactone saponin (4), and two new oleanane-type triterpenoids (5 and 6), together with eight known triterpenoids (7-14). Compound 1, a 19-oxo-18,19-seco-28-norursane, possesses a conjugated diene between C-12 and C-17. Several of the isolated compounds (1, 5, 7, 11, and 13) exhibited moderate activities in anti-inflammatory assays in vitro.