Background:Schistosomiasis,a parasitic disease also known as bilharzia and snail fever,is caused by different species of flatworms,such as Schistosoma mansoni(S.mansoni).Thioredoxin glutathione reductase(TGR)from S.ma...Background:Schistosomiasis,a parasitic disease also known as bilharzia and snail fever,is caused by different species of flatworms,such as Schistosoma mansoni(S.mansoni).Thioredoxin glutathione reductase(TGR)from S.mansoni(SmTGR)is a well-characterized drug target for schistosomiasis,yet no anti-SmTGR compounds have reached clinical trials,suggesting that therapeutic development against schistosomiasis might benefit from additional scaffolds targeting this enzyme.Methods:A high-throughput screening(HTS)assay in vitro against SmTGR was developed and applied to a diverse compound library.SmTGR activity was quantified with ThioGlo®,a reagent that fluoresces upon binding to the free sulfhydryl groups of the reaction product GSH(reduced glutathione).Results:We implemented an HTS effort against 59,360 synthetic compounds.In the primary screening,initial hits(928 or 1.56%)showing greater than 90%inhibition on SmTGR activity at a final concentration of 10μM for each compound were identified.Further tests were carried out to confirm the effects of these hits and to explore the concentration-dependent response characteristics.As a result,74 of them(0.12%)representing 17 chemical scaffolds were confirmed and showed a great concentration-dependent inhibitory trend against SmTGR,including structures previously shown to be lethal to schistosomal growth.Of these,two scaffolds displayed a limited structure-activity relationship.When tested in cultured larvae,39 compounds had cidal activity in 48 h,and five of them killed larvae completely at 3.125μM.Of these,three compounds also killed adult worms ex vivo at concentrations between 5μM and 10μM.Conclusion:These confirmed hits may serve as starting points for the development of novel therapeutics to combat schistosomiasis.展开更多
基金We are indebted to Zhiyun Zhang for technical assistance.This work was partially supported by grants from the World Health Organization’s Special Programme for Research and Training in Tropical Diseases(WHO/TDR A80553)the Ministry of Science and Technology of China(to MWW:2014DFA31130)+2 种基金the National Health and Family Planning Commission of China(to MWW:2012ZX09304-011,2013ZX09401003-005,2013ZX09507-001 and 2013ZX09507-002)the Shanghai Science and Technology Development Fund(to MWW:13DZ2290300 and 15DZ2291600)the Thousand Talents Program in China(to MWW).Schistosome-infected mice and snails were provided by the NIAID Schistosomiasis Resource Center at the Biomedical Research Institute(BEI)(Rockville,MD,USA)through NIH-NIAID Contract HHSN272201000005I for distribution through BEI Resources.The funders had no role in study design,data collection and analysis,decision to publish,or manuscript preparation.
文摘Background:Schistosomiasis,a parasitic disease also known as bilharzia and snail fever,is caused by different species of flatworms,such as Schistosoma mansoni(S.mansoni).Thioredoxin glutathione reductase(TGR)from S.mansoni(SmTGR)is a well-characterized drug target for schistosomiasis,yet no anti-SmTGR compounds have reached clinical trials,suggesting that therapeutic development against schistosomiasis might benefit from additional scaffolds targeting this enzyme.Methods:A high-throughput screening(HTS)assay in vitro against SmTGR was developed and applied to a diverse compound library.SmTGR activity was quantified with ThioGlo®,a reagent that fluoresces upon binding to the free sulfhydryl groups of the reaction product GSH(reduced glutathione).Results:We implemented an HTS effort against 59,360 synthetic compounds.In the primary screening,initial hits(928 or 1.56%)showing greater than 90%inhibition on SmTGR activity at a final concentration of 10μM for each compound were identified.Further tests were carried out to confirm the effects of these hits and to explore the concentration-dependent response characteristics.As a result,74 of them(0.12%)representing 17 chemical scaffolds were confirmed and showed a great concentration-dependent inhibitory trend against SmTGR,including structures previously shown to be lethal to schistosomal growth.Of these,two scaffolds displayed a limited structure-activity relationship.When tested in cultured larvae,39 compounds had cidal activity in 48 h,and five of them killed larvae completely at 3.125μM.Of these,three compounds also killed adult worms ex vivo at concentrations between 5μM and 10μM.Conclusion:These confirmed hits may serve as starting points for the development of novel therapeutics to combat schistosomiasis.
