title: Inhibition of tetramethylpyrazine on P-gp, MRP2, MRP3 and MRP5 in multidrug resistant human hepatocellular carcinoma cells.
abstract: Some membrane transporters in liver, such as P-glycoprotein, multidrug resistance-associated protein 2 (MRP2), MRP3, and MRP5 can lead to a complex multidrug resistance (MDR) to antineoplastic agents. How to inhibit these proteins is still an issue. Tetramethylpyrazine is a bioactive constituent isolated from the root of Ligusticum chuanxiong Hort, a Chinese herb. Recent studies showed that it can enhance the chemosensitivity effects of a drug on human hepatocellular carcinoma cells, acting as a multidrug resistance modulator. In this study, the reversal effect of TMP on MDR was evaluated and its activity mechanism in vitro was explored. The IC50 value shows that TMP reversed the multidrug resistance of BEL-7402/ADM cells 9.23-fold (P<0.01) at the concentration of 600 microM. The mean fluorescence intensity of ADM in BEL-7402/ADM cells with TMP was found to be 163.78+/-39.5% (P<0.01) versus in BEL-7402/ADM cells without TMP by flow cytometry and 126.73+/-28.72% in BEL-7402/ADM cells with TMP versus in BEL-7402/ADM cells without TMP (P<0.01) by high performance liquid chromatography, respectively. It was also found that the mRNA level of multidrug resistant gene MDR1, MRP2, MRP3 and MRP5 and the level of the proteins they encode were decreased after treatment with TMP, indicating that TMP can effectively reverse the MDR in BEL-7402/ADM cells, and its activity mechanism may be correlated with the down-regulation of expression in these transporters.
authors: Department of Pharmacology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China.
authors: Xuan-Bin
authors: XB
authors: Wang
authors: Shan-Shan
authors: SS
authors: Wang
authors: Qiu-Fang
authors: QF
authors: Zhang
authors: Ming
authors: M
authors: Liu
authors: Hong-Liang
authors: HL
authors: Li
authors: Ying
authors: Y
authors: Liu
authors: Jia-Ning
authors: JN
authors: Wang
authors: Fei
authors: F
authors: Zheng
authors: Ling-Yun
authors: LY
authors: Guo
authors: Ji-Zhou
authors: JZ
authors: Xiang
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000037:antagonists & inhibitors*; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy*; D045744:Cell Line, Tumor; D004317:Doxorubicin / Q000494:pharmacology; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D020128:Inhibitory Concentration 50; D008113:Liver Neoplasms / Q000188:drug therapy*; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000037:antagonists & inhibitors*; D010936:Plant Extracts / Q000494:pharmacology; D018517:Plant Roots / Q000378:metabolism; D011719:Pyrazines / Q000494:pharmacology*
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000903:Antibiotics, Antineoplastic; D004317:Doxorubicin; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D010936:Plant Extracts; D011719:Pyrazines; C000715087:ABCC2 protein, human; C120809:ABCC5 protein, human; C114462:multidrug resistance-associated protein 3; C017953:tetramethylpyrazine