Taxol-induced alteration of intracellular amino-acid profile related to human cervical carcinoma HeLa cell death.

The anti-tumor action of Taxol was investigated in the changes of amino-acids involved in tumor cell survival. By tracing the intracellular amino-acid profiles of HeLa cells treated with non-conditioned and three conditioned media (Taxol, L-alanine, and Taxol + L-alanine), it was observed that an alteration of amino-acid metabolism participates in Taxol-induced death of HeLa cells. The contents of 18 out of 21 detected amino-acids are 5-95% and the ones of lysine and methionine are 158 and 117% of the corresponding contents in the control after treatment with Taxol for 24 h, respectively. Addition of L-alanine inhibited cell apoptosis upon Taxol treatment by partially blocking the increase of lysine and methionine and reversing decrease trend of alanine, glycine, and glutamic acid. These results suggest that interference of amino-acid metabolism might be an important mechanism of Taxol cytotoxicity.

Functional analysis of cultured neural cells for evaluating cold/cool- and hot/warm-natured Chinese herbs.

Recently, modern scientific research has been required to understand pharmacological basis of traditional Chinese medicine (TCM) theory based on the ancient clinical experience, and to investigate the molecular mechanisms of action of Chinese herbs. Here, 20 Chinese herbs, classified into 4 properties (hot, warm, cold and cool) of TCM, were analyzed for their ability to exhibit antioxidant action, to enhance glucose uptake by murine microglia N9 cells, and to influence neurotransmitter norepinephrine (NE) release from rat pheochromocytoma PC12 cells. We found a generally protective effect of both hot/warm-natured and cold/cool-natured herbs against H(2)O(2)-induced N9 cell death, partially by elevating superoxide dismutase (SOD) activity. Glucose uptake was elevated after treatment with some hot/warm-natured herbs. In addition, most herbs with hot/warm nature tended to stimulate NE release, while such stimulatory effect was not observed in the herbs with cold/cool nature. Two cold/cool-natured herbs, Rhizoma coptidis and Radix scutellariae, even significantly suppressed the release. These results suggest that the distinct abilities of Chinese herbs to regulate neural cell functions appear to be correlated with their natures identified in traditional TCM theory, and may be a useful guide for their utility in neural degenerative diseases.

[Analysis of volatile constituents of root and rhizome of Asarum heterotropoides Fr. var. mandshuricum (Maxim.) Kitag. by gas chromatography-mass spectrometry].

The volatiles of root and rhizome of Asarum heterotropoides Fr. var. mandshuricum (Maxzim. ) Kitag. were extracted with n-hexane and analyzed by capillary gas chromatography-flame ionization detection and gas chromatography-mass spectrometry (GC-MS) with the same column HP-5 (30 m x 0.25 mm i.d.). Initial oven temperature was kept at 40 degrees C for 2 min, then raised to 160 degrees C at 3 degrees C /min, immediately raised to 250 degrees C at 6 degrees C /min, and kept 250 degrees C for 23 min. According to GC-MS analysis, 36 compounds were identified. The main components are safrole, methyleugenol, 3,5-dimethoxytoluene, pentadecane, N-isobutyldodecatetraenamide. Furthermore, the analysis results of root and rhizome were compared. The results indicate that the fundamental constituents are nearly the same, but the quantities of volatiles in root are richer than those in rhizome. In addition, 8 compounds are selected as the criteria of quality control, including 3-carene, 1,8-cineole, eucarvone, methyleugenol, safrole, myristicin, pentadecane and N-isobutyldodecatetraenamide.