青蒿素衍生物对卡氏肺孢子虫基因的影响

The effects of three artemisinin derivates on genes of Pneumocystis carinii

目的 研究双氢青蒿素、蒿甲醚、青蒿琥酯对卡氏肺孢子虫 5SrRNA基因、线粒体rRNA大亚基基因 (mtLSUrRNA)、胸腺嘧啶核苷酸合成酶 (TS)基因的影响。方法 以上述 3种药物治疗实验大鼠肺孢子虫肺炎 ,治疗结束后收集鼠肺 ,以酚 -氯仿抽提法抽提肺总DNA。以PCR方法扩增肺孢子虫的上述 3基因 ,以双脱氧末端终止法测定PCR产物的核苷酸序列 ,并研究双氢青蒿素对基因序列的影响。结果 3种药物作用过的虫体均未见TS基因扩增产物 ,部分虫体无 5SrRNA基因、mtLSUrRNA基因扩增产物。经双氢青蒿素作用过的与正常肺孢子虫的 5SrRNA基因、mtLSUrRNA基因分别有16 5 %、15 .2 %序列差异。结论 3种青蒿素衍生物可破坏肺孢子虫TS基因。双氢青蒿素可致 5SrRNA基因。

Aim To study the effect of three artemisinin derivates (dihydroartemisinin,artemether and sodium artesunate) on three genes of Pneumocystis carinii.Methods P.carinii pneumonia (PCP) rat models were established by injection with cortisone acetate twice a week for 6 weeks,then the PCP rats were treated with dihydroartemisinin at 60mg/kg,artemether at 80mg/kg,sodium artesunate at 60mg/kg once a day for 5 days respectively.After the therapy,the control and treated rat lungs were collected.Total lung DNA was extracted by phenol-chloroform extraction method.Polymerase chain reaction (PCR) was conducted for amplification of 5S rRNA gene,the large subunit mitochondrial rRNA (mt LSU rRNA) gene,thymidylate synthase (TS) gene of P.carinii.The PCR products were purified and sequenced directly.Results All P.carinii samples treated with the arteminsinin deviates were negative for TS gene's PCR amplification.Some samples treated with the derivates were also negative for 5S rRNA gene and mt LSU rRNA gene's amplification.The identity of nucleotide sequences of 5S rRNA gene,mt LSU rRNA gene of P.carinii from the control sample to that from the sample treated with dihydroartemisinin,however,was 16.5%,15.2% respectively.Conclusion It suggested that the artemisinin derivates could destroy TS gene of P.carinii,and affect 5S rRNA gene and mt LSU rRNA gene of P.carinii to some extent.Dihydroartemisinin could cause some base mutations in 5S rRNA gene and mt LSU rRNA gene of P.carinii.