ABSTRACT
Seventy-nine injectable herb extractions have been approved by the Chinese Food and Drug Administration (CFDA) and are frequently administered intravenously for various diseases. Unfortunately, herb-drug interactions are under-investigated and sometimes overlooked in the clinic. In the present investigation the in vitro inhibition of 9 drug metabolizing enzymes including CYP1A, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, and CYP3A was assessed using an appropriate probe substrate for each enzyme with human liver microsomes. Metabolite formation was quantified using a validated and sensitive high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay. The IC50 of each herb extract was estimated using a concentration range from 5% to 0.5%, and the time-dependent inhibition of the nine CYP450 isoenzymes was also determined. Of the 79 approved iv herb injectables, 37 inhibited CYP1A, 24 inhibited CYP2A6, 41 inhibited CYP2B6, 36 inhibited CYP2C8, 31 inhibited CYP2C9, 41 inhibited CYP2C19, 13 inhibited CYP2D6, 25 inhibited CYP2E1, and 42 inhibited CYP3A with 50% or greater inhibition at a test concentration of 5% (v/v). IC50 differences were noted between pre-incubation or co-incubation assays with HLM for 30 min, with the time-dependent inhibitory (TDI) effects were observed with 2 injectables on CYP1A, 5 injectables on CYP2A6, 5 injectables on CYP2B6, 6 injectables on CYP2C8, 1 injectable on CYP2D6 and 6 injectables on CYP3A. Collectively, the results demonstrate that potential herb-drug interactions (HDIs) can occur with the concomitant use of herb injectables and prescription drugs that are cleared by CYP450 enzymes, and further investigation is warrant for the clinical relevance of these interactions.
ABSTRACT
Objective:To explore the potential targets and related mechanism involved in the paclitaxel resistance to ovarian cancer. Method:Ovarian cancer A2780 cells and A2780 paclitaxel-resistant cells （A2780/T） were treated by 2， 4， 8， 16， 32， 64， 128， 256 μmol·L<sup>-1</sup> paclitaxel （PTX） for 24 h or 48 h respectively <italic>in vitro</italic>. The proliferation rate of A2780 cells and A2780/T cells treated with paclitaxel was determined by methyl thiazolyl tetrazolium （MTT） colorimetric method assay. A2780 and A2780/T cells were analyzed by LC-MS/MS Label-Free quantitative proteomics to identify and screen differentially expressed proteins in the two groups of cells. Gene ontology （GO） annotation and Kyoto encyclopedia of genes and genomes （KEGG） pathway analysis were used to determine the potential biomarkers of paclitaxel resistance in ovarian cancer. Conventionally cultured A2780 cells were used as a control group， and A2780/T cells were treated with 0， 1， 4 μmol·L<sup>-1</sup> PTX. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot methods were used to detect and verify the mRNA and protein expression levels of potential target transforming growth factor-<italic>β</italic>-activated kinase 1 binding protein 1 （TAB1） and its downstream related molecules transforming growth factor-<italic>β</italic>-activated kinase （TAK1） and p38. Result:After PTX treatment for 24 h and 48 h， the cell viability of A2780 and A2780/T cells decreased. The inhibitory rate of PTX on A2780 cells was significantly higher than that of A2780/T cells. In A2780 cells， the IC<sub>50</sub> of PTX treatment for 48 h was 0.002 μmol·L<sup>-1</sup>， while in A2780/T cells， the IC<sub>50 </sub>of PTX was greater than the maximum concentration of 128 μmol·L<sup>-1</sup>， indicating that A2780/T cells were resistant to PTX compared with A2780 cells. 441 differentially expressed proteins and 421 special differentially expressed proteins between A2780/T and A2780 cells were screened by label-free quantitative proteomic analysis. GO function enrichment analysis showed that the binding proteins accounted for the majority （80%） among the differentially expressed proteins. According to the results of KEGG pathway analysis and expression site analysis， TAB1 might be a potential biomarker in paclitaxel-resistant ovarian cancer. Compared with A2780 cells， mRNA and protein expression levels of TAB1 in A2780/T cells were significantly reduced （<italic>P</italic><0.01）. mRNA expression of TAK1 and p38 that interacted with TAB1 were also significantly reduced （<italic>P</italic><0.05， <italic>P</italic><0.01）， while there was no significant change in protein expression. Conclusion:TAB1 may be a potential biomarker of paclitaxel resistance to ovarian cancer ， and its mechanism may be related to the TAB1/TAK1/p38 MAPK pathway.
ABSTRACT
Zebrafish (Danio rerio) is a simple biological labora-tory animal, with similar biological structure and physiological functions to mammals. Almost transparent embryos, in vitro de-velopment of embryos and up to 87% of human genetic similari- ties enable a wide application of zebrafish in the field of pharma-ceutical research. In this paper, we have studied the application of zebrafish in drug metabolism, the research of Chinese medi-cine, the evaluation of drug toxicology and safety, the screening of drugs and the discovery of new drugs, the research of regener- ative drugs, so as to provide new ideas of zebrafish in the field of pharmacy.
ABSTRACT
Organic anion transporting polypeptide 1B1 (OATP1B1) is an important liver-specific uptake transporter, which mediates transport of numerous endogenous substances and drugs from blood into hepatocytes. To identify and investigate potential modulators of OATP1B1 from natural products, the effect of 21 frequently used natural compounds and extracts on OATP1B1-mediated fluorescein methotrexate transport was studied by using Chinese hamster ovary cells stably expressing OATP1B1 (CHO-OATP1B1) in 96-well plates. This method could be used for the screening of large compound libraries. Our studies showed that some flavonoids (e.g., quercetin, quercitrin, rutin, chrysanthemum flavonoids and mulberrin) and triterpenoids (e.g., glycyrrhetinic acid and glycyrrhizic acid) were inhibitors of OATP1B1 with IC50 values less than 16 µmol · L(-1). The IC50 value of glycyrrhetinic acid on OATP1B1 was comparable to its blood concentration in clinics, indicating an OATPlB1-mediated drug-drug interaction could occur. Structure-activity relationship analysis showed that flavonoids had much higher inhibitory activity than their glycosides. Furthermore, the type and length of saccharides had a significant effect on their activity. In addition, we used OATP1B1 substrates fluvastatin and rosuvastatin as probe drugs to investigate the substrate-dependent effect of several natural compounds on the function of OATP1B1 in vitro. Our results demonstrated that the effect of these natural products on the function of OATPlB1 was substrate-dependent. In summary, this study would be conducive to predicting and avoiding potential OATP1B1-mediated drug-drug and drug-food interactions and thus provide the experimental basis and guidance for rational drug use.