Study on the in vivo toxic mechanism of xixin based on trace elements determination by inductively coupled plasma-mass spectrometry.

BACKGROUND: Xixin has been widely used as a traditional Chinese medicine for headache, toothache and inflammatory diseases. Clinical investigation indicated that adverse drug reactions occurred with an overdose of xixin, but the toxic mechanism of xixin in vivo based on trace elements has not been researched yet. OBJECTIVE: To explore the in vivo toxic mechanism of xixin induced by trace elements. MATERIALS AND METHODS: The contents of trace elements in the serum and liver of mice were determined by inductively coupled plasma-mass spectrometry (ICP-MS) after obtaining xixin extracts. Principal component analysis (PCA) and cluster analysis (CA) were performed between the trace elements' content and dosage using the software GeneSpring 12.1 to analyze the main toxic elements in vivo. RESULTS: Trace elements' contents were obviously raised after xixin extracts were taken as a dosage of 150 mg/mL and 50 mg/mL, respectively. Na, Ca, Cu and Cd in serum and Ca and Zn in liver were the main trace elements inducing the toxic reaction of xixin. CONCLUSION: Xixin possesses the potential function of indirectly upregulating trace elements in vivo. This study, for the first time, elucidated the in vivo toxic mechanism of xixin based on trace elements. This method could also be utilized in the research of corresponding aspects.

Effect of osthol on apoptosis and bone resorption of osteoclasts cultured in vitro / 药学学报

This study is to investigate the effect of osthol on osteoclasts' activity, bone resorption as well as apoptosis in vitro, and explore the mechanism of osthol in preventing osteoporosis. Osteoclasts were separated from long-limb bones of new born rabbits, cultured in 24-well plate with glass slices and bone slices, and treated by 1 x 10(-5) mol x L(-1) osthol. Osteoclasts were identified by observing live cells with phase contrast microscope, HE staining, TRAP staining and toluidine blue staining of bone resorption pits. The numbers of bone resorption pits were counted as well as the surface area of bone resorption on bone slice. Osteoclasts were stained with acridine orange to detect the cell apoptosis. The ratio of apoptotic osteoclasts was observed under fluorescence microscope. The gene expression of RANKL, OPG, TRAP and p-JNK1/2 protein expression were examined using real time PCR and Western blotting, respectively. Comparing with the control group without osthol, the rates of apoptotic osteoclasts increased obviously and the number and area of bone resorption pits decreased evidently with 1 x 10(-5) mol x L(-1) osthol. There is significant difference between control group and experiment group treated by 1 x 10(-5) mol x L(-1) osthol. Therefore, the osthol through RANK+RANKL/TRAF6/Mkk/JNK signal pathway inhibits the osteoclasts activity, enhances osteoclasts apoptotic and inhibits the bone resorption.