Total synthesis and anti-viral activities of an extract of Radix isatidis.

Radix isatidis (Banlangen), a famous traditional Chinese medicine, has been used for thousands of years in China due to its anti-viral activity. Through our research, we inferred that the anti-viral activity of Radix isatidis depended on the water-soluble part. Among the components of this extract, the isoquinoline derivative 1 was isolated for the first time and has shown better anti-viral activity than other constituents. In this study, to solve the problem of sourcing sufficient quantities of compound 1, a total synthesis route is described, and several analogues are also evaluated for their anti-viral activities. Among them, compound 8 shown potent anti-viral activity with an IC50 value of 15.3 µg/mL. The results suggested that isoquinoline derivatives possessed potent anti-viral activity and are worthy further development.

Development and validation of a high-performance liquid chromatography-tandem mass spectrometry method for the rapid simultaneous quantification of aconitine, mesaconitine, and hypaconitine in rat plasma after oral administration of Sini decoction.

A rapid, sensitive, and specific liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS-MS) method was developed and validated for simultaneous determination of aconitine (AC), mesaconitine (MA), and hypaconitine (HA), the three toxic constituents from Sini decoction (SND) in rat plasma. After the addition of citalopram as the internal standard (IS), plasma samples were basified with 100 microL 10% ammonium hydroxide, and then extracted with 1 mL ethyl acetate. Chromatographic separation was performed on a CN column (250 mm x 4.6 mm, 5 microm) with a mobile phase of methanol/40 mM ammonium acetate/formic acid (950:45:5, v/v/v) at the flow rate of 1.0 mL/min. Analytes were determined in a triple-quadrupole mass spectrometer in the selected reaction-monitoring (SRM) mode using electrospray source with positive mode. The method was validated over the concentration ranges of 0.01-10 ng/mL for AC, MA, and HA. The variation coefficients were always < 15% for both intraday and interday precision for each analyte. Mean accuracies were also within +/-15%. The method was proved to be sensitive, rapid, specific, accurate, and reproducible. It has been successfully applied to the pharmacokinetics study on rats after oral administration of SND.

[Effect of neferine on adriamycin-resistance of thermotolerant hepatocarcinoma cell line HepG2/thermotolerance].

BACKGROUND & OBJECTIVE: Nowadays, reversing the multidrug resistance (MDR) of thermotolerant carcinoma cells is a hot topic in tumor thermatology. This study was to investigate the adriamycin (ADR)-resistance of thermotolerant hepatocarcinoma cell line HepG2/thermotolerance and the effect of neferine (Nef) on the ADR-resistance of HepG2/thermotolerance cells. METHODS: Cell proliferation was measured by MTT assay. Cell apoptosis was detected by flow cytometry (FCM) with PI staining. The expression of Bcl-2 was measured by FCM using fluorescein isothiocyanate (FITC)-conjugated anti-bcl-2 antibodies. RESULTS: The proliferation rate and apoptosis rate of HepG2/thermotolerance cells cultured in 43 degrees C for 24 h were (89.6+/-5.4)% and (13.6+/-5.4)%, respectively; however, those of HepG2 cells were (23.9+/-3.6)% and (68.9+/-7.3)%, respectively. The 50% inhibition concentration (IC50) of ADR was 10.8 times higher for HepG2/thermotolerance cells than for HepG2 cells [(113.7+/-12.7) micromol/L vs. (10.5+/-2.3) micromol/L]. When treated with 1, 10, 100 micromol/L ADR at 37 degrees C for 24 h, the apoptosis rates of HepG2/thermotolerance cells were (9.3+/-2.6)%, (17.8+/-7.3)%, and (32.9+/-8.6)%, respectively, but those of HepG2 cells were (14.3+/-3.9)%, (38.9+/-6.8)%, and (62.7+/-5.9)%, respectively. In the presence of 10 and 40 micromol/L Nef, the IC50 of ADR for HepG2/thermotolerance cells was significantly decreased from (113.7+/-12.7) micromol/L to (63.7+/-5.6) micromol/L and (16.8+/-2.8) micromol/L, and the cell apoptosis induced by 10 micromol/L ADR was significantly increased from (17.8+/-4.3)% to (26.8+/-5.9)% and (34.9+/-8.7)%, respectively. Bcl-2 was overexpressed in HepG2/thermotolerance cells, whereas it was down-regulated when the cells were treated with 40 micromol/L Nef for 24 h. CONCLUSIONS: HepG2/thermotolerance cells are ADR-resistant. Nef may reverse the ADR-resistance of HepG2/thermotolerance cells by down-regulating Bcl-2 expression.