The Ca. LSU intron flanking a 129 bp cxon upstream and a fOO bp exondownstream was inserted into the lacZ gene on pRS426 to transform E. coli. Northern blot analysisand RT-PCR showed that splicing of Ca. LSU in E. col...The Ca. LSU intron flanking a 129 bp cxon upstream and a fOO bp exondownstream was inserted into the lacZ gene on pRS426 to transform E. coli. Northern blot analysisand RT-PCR showed that splicing of Ca. LSU in E. coli is efficient upon inducible expression of theprecursor RNA, In contrast, co-lranscriptional self-splicing of the intron in vitro is much lessactive. Therefore, this E. coli splicing system can be used as a better model to investigate theeffect of the ribozyme inhibitors on Ca. LSUsplicing in living cell. We examined (he effects ofneomycin sulfatc and pentamidine on Ca. LSU splicing in E. coli, and found that these drugsdoes-dependently inhibit the intron splicing. However, heomycin is more potent than pentamidine inthis action.展开更多
Objective Traditional Chinese medicines（TCMs） as natural therapeutic agents have been widely used and received great attention over the world.However,the information on them to cause herb-drug interactions mediated ...Objective Traditional Chinese medicines（TCMs） as natural therapeutic agents have been widely used and received great attention over the world.However,the information on them to cause herb-drug interactions mediated by cytochrome P450（CYP） enzymes is limited.The present study aims to evaluate the inhibitory effects of 11 commonly used TCMs,including Nelumbinis Folium,Ginseng Radix et Rhizoma,Ziziphi Spinosae Semen,Chrysanthemi Flos,Lonicera Japonica Flos,Lycii Fructus,Cassiae Semen,Poria,Crataegi Fructus,Schisandrae Chinensis Fructus,and Polygonati Rhizoma,on the five human major CYP isoenzymes 2C19,2D6,3A4,2E1,and 2C9.Methods An in vitro cocktail method was used.Results The aqueous extracts of all tested TCMs were found no significant inhibitory effect,with IC50 values higher than 100 μg/mL while,the ethanolic extracts of some herbs showed more potent inhibition.These herbs include Nelumbinis Folium with IC50 values of 1 2.05 and 61.43 μg/mL on CYP2D6 and CYP2E1,Schisandrae Chinensis Fructus with IC50 values of 64.42 and 47.24 μg/mL on CYP2C1 9and CYP3A4,and Chrysanthemi Flos with IC50 values of 45.25 μg/mL on CYP2C9,respectively.Conclusion Co-administration of these TCMs and their products with conventional medicines should be paid much attention to,and their potential inhibitory effects on CYP enzyme activities need to be further investigated.展开更多
基金Supported by the National Natural Science Foundation of China (30170213) and the Foundation of Wuhan University(0000028)
文摘The Ca. LSU intron flanking a 129 bp cxon upstream and a fOO bp exondownstream was inserted into the lacZ gene on pRS426 to transform E. coli. Northern blot analysisand RT-PCR showed that splicing of Ca. LSU in E. coli is efficient upon inducible expression of theprecursor RNA, In contrast, co-lranscriptional self-splicing of the intron in vitro is much lessactive. Therefore, this E. coli splicing system can be used as a better model to investigate theeffect of the ribozyme inhibitors on Ca. LSUsplicing in living cell. We examined (he effects ofneomycin sulfatc and pentamidine on Ca. LSU splicing in E. coli, and found that these drugsdoes-dependently inhibit the intron splicing. However, heomycin is more potent than pentamidine inthis action.
基金Ministry of Science and Technology of China(1108,2011DFA32730 and 2012ZX09301002-001)
文摘Objective Traditional Chinese medicines（TCMs） as natural therapeutic agents have been widely used and received great attention over the world.However,the information on them to cause herb-drug interactions mediated by cytochrome P450（CYP） enzymes is limited.The present study aims to evaluate the inhibitory effects of 11 commonly used TCMs,including Nelumbinis Folium,Ginseng Radix et Rhizoma,Ziziphi Spinosae Semen,Chrysanthemi Flos,Lonicera Japonica Flos,Lycii Fructus,Cassiae Semen,Poria,Crataegi Fructus,Schisandrae Chinensis Fructus,and Polygonati Rhizoma,on the five human major CYP isoenzymes 2C19,2D6,3A4,2E1,and 2C9.Methods An in vitro cocktail method was used.Results The aqueous extracts of all tested TCMs were found no significant inhibitory effect,with IC50 values higher than 100 μg/mL while,the ethanolic extracts of some herbs showed more potent inhibition.These herbs include Nelumbinis Folium with IC50 values of 1 2.05 and 61.43 μg/mL on CYP2D6 and CYP2E1,Schisandrae Chinensis Fructus with IC50 values of 64.42 and 47.24 μg/mL on CYP2C1 9and CYP3A4,and Chrysanthemi Flos with IC50 values of 45.25 μg/mL on CYP2C9,respectively.Conclusion Co-administration of these TCMs and their products with conventional medicines should be paid much attention to,and their potential inhibitory effects on CYP enzyme activities need to be further investigated.
