【作者】 瞿畅；

【导师】 王一飞；

【作者基本信息】 暨南大学 ， 微生物与生化药学， 2010， 硕士

【摘要】 目的：本研究主要研究南药的系列提取物抗单纯疱疹病毒(Herpes Simplex Virus,HSV)1型的药效学活性,并且利用计算机辅助药物设计的方法,探讨桔单宁类化合物抗HSV-1的定量构效关系,为开发新型的抗单纯疱疹病毒药物提供理论依据。方法：1.利用MTT(四甲基偶氮唑蓝)法检测南药提取物对Vero细胞的毒性作用；利用细胞病变效应(Cytopathic Effect, CPE)法与空斑减数法(Plaque Re-duction Assay, PRA)检测南药提取物抗HSV-1的活性。2.在本课题组的前期工作基础上,结合文献提供的桔单宁类化合物抑制HSV-1的活性数据信息,建立桔单宁类化合物抗HSV-1的结构-活性数据库。3.利用2D-QSAR研究方法,探讨化合物中与生物活性密切相关的原子连接片段；4.利用3D-QSAR研究方法(包括CoMFA以及CoMSIA),建立定量构效关系模型,探讨化合物的不同力场对其活性的影响。结果：1.南药提取物中有部分样品显示出了较好的抗HSV-1的活性,其中余甘子果实提取物(SML-P14-E1)、直杆桉果实提取物(SML-P18-E2,SML-P18-E3)和番石榴叶子提取物(SML-P44)四个样品的治疗指数(TI值)均大于15。2.构建了桔单宁类化合物对HSV-1抑制作用的2D-QSAR模型(其交叉验证系数q2为0.808,相关系数R2为0.900,标准偏差为0.146,最佳组分数为3,分子全息长度为151),证明该2D-QSAR模型能够很好地描述化合物中与生物活性密切相关的原子片段与活性之间的关系。3.利用CoMFA方法来建立桔单宁类化合物抗HSV-1病毒活性的3D-QSAR模型,该模型交叉验证系数q2=0.370,相关系数R2=0.951,标准偏差为0.102,最佳组分数为3。由于该模型交叉验证系数q2=0.370<0.4,故该模型的预测能力较差,不予采用。4.使用CoMSIA方法证实桔单宁类化合物的疏水场、静电场和氢键受体场与其对HSV-1的抑制活性存在明显的相关性。该模型的交叉验证系数q2=0.660(>0.6,表明该模型预测能力较好),相关系数R2=0.943,标准偏差为0.116,最佳组分数为4。结论：1.南药提取物中存在一些有潜力的活性成分,如余甘子、直杆桉、番石榴等植物来源的提取物,可供进一步的研究。2.在桔单宁类化合物对HSV-1的抑制活性的构效关系研究中,2D-QSAR模型能够利用桔单宁类化合物分子中原子的连接方式来描述其抑制HSV-1的构效关系；同时,3D-QSAR模型能够通过桔单宁类化合物分子周围不同的力场来描述其构效关系。3.从所构建的2D及3D-QSAR模型,结果表明,桔单宁类化合物中没食子酰基与化合物抗HSV-1病毒的活性密切相关,该类化合物的疏水场对于其抗病毒活性非常重要,疏水基团的引入有利于该类化合物对HSV-1病毒的抑制活性。更多还原

【Abstract】 Objective:To evaluate anti-HSV-1 activities of a series of extracts from nanyao, and use of computer-aided drug design approach to study the quantitative structure-activity relationship of the gallic tannins as HSV-1 inhibitors, to provide theoretical basis for the development of novel antiviral drugs.Methods:1) Cytotoxic effects of the extracts from nanyao on Vero cells were determined by MTT (3-{4,5-dimethylthiazol-2-y}-2-5-diphenytetrazolium bromide) method. Anti-viral activities of the extracts were examined by cytopathic effect (CPE) observation and plaque reduction assay (PRA).2) Based on the previous work of our team, combined with the literatures which reported anti-HSV-1 activities of gallic tannins, the structure-activity database of gallic tannins was established.3) 2D-QSAR model was established by using HQSAR method, to explore the molecular fragments which were closely related to the bio-activity of the compounds.4) 3D-QSAR model was established by using CoMFA and CoMSIA methods, to investigate the relationship between different force fields of the compounds and its bio-activities.Results:1) Some of the extracts from nanyao have showed anti-HSV-1 activity, especially extracts from the fruits of Phyllanthus emblica (SML-P14-E1), fruits of Eucalyptus maideni (SML-P18-E2, SML-P18-E3) and leaves of Psidium guajava L. (SML-P44). All of these samples’TI values are higher than 15. 2) The 2D-QSAR model showed that the cross-validated coefficient q2 was 0.808, the non cross-validation R2 was 0.900, the standard deviation SE was 0.146, component was 3, best length was 151, which means the 2D-QSAR model have good predictive ability.3) 3D-QSAR model, which was established by CoMFA method, showed that the cross-validated coefficient q2 was 0.370, the non cross-validation R2 was 0.951, the standard deviation SE was 0.102, and component was 3. In this model, the q2 was smaller than 0.4, which indicated the predictive ability of this model is not good enough. Accordingly, the CoMFA model was rejected.4) 3D-QSAR model which was build using CoMSIA method showed that the cross-validated coefficient q2 was 0.660, the non cross-validation R2 was 0.943, the standard deviation SE was 0.116, and component was 4. In this model, the q2 was higher than 0.6, demonstrated this model have good predictive ability. In this CoMSIA model, evidence showed the hydrophobic field, hydrogen acceptor and electrostatic field of gallic tannins have great relevant with the anti-HSV-1 activities.Conclusion:1) There are some active constituents among the extracts for further research, such as Phyllanthus emblica (SML-P14-E1), Eucalyptus maideni (SML-P18-E2, SML-P18-E3) and Psidium guajava L. (SML-P44).2) Evaluation of the gallic tannins as HSV-1 inhibitor structure-activity relationship revealed the 2D and 3D-QSAR models can be used in this research.3) According to the models, galloyl played an important role on antiviral activity. Meanwhile, hydrophobic field was very essential. Hydrophobic groups can be helpful to increase the anti-HSV-1 activity of gallic tannins.更多还原