Screening And Identification Of Active Compounds With The Animal Model Of Caenorharbditis Elegans

Animal disease models and high-throughput drug screening platforms have played a very important role in drug discovery.Caenorhabditis elegans has a short life cycle with transparent body,which can be easily observed and operated.Using C.elegans as a high-throughput screening model can shorten the research period,save costs and improve the efficiency of drug screening,which is of great significance to the development of new drugs.In this study,the animal models of C.elegans were established to screen the active compunds isolated from sugacane leaves and medicnial plants grown in Guangxi,as well as nematicidal compound from tropical plants.In our study,the C.elegans lifespan model was established and used to screen the extracts from sugarcane leaves.Our results showed that the crude extract of dichloromethane was able to significantly extend the lifespan of worms,the activity was positively correlated with the concentration,and the impact on the lifespan of the worms was more significant at the late stage of lifespan.These results indicate that the crude dichloromethane extract of sugarcane leaves contains active components that can significantly extend the lifespan of worms.Also,the nematicide screening and identification model was established and used to screen the EMS-induced mutants that are resistant to ketone A.Around 100,000 randomly mutated worms were screened against 20 ppm ketone A and 4 ketone A-resistant mutants were obtained.Further analysis confirmed that No.1 mutant showed the best ketone A-resistance and grew normally in a solution with 250 ppm of ketone A.Furthermore,we showed that the mutation of ketone A-resistance of the No.1 mutant was different from known mutations of piperazines-,ivermectin-and levamisol-resistence,suggesting a different mechanism for ketone A-resistance and therefore Ketone A is a promising nematicidal drug.In addition,a lipid metabolism model of C.elegans with GFP-or m Cherry-labeled lipid droplets was established.By using this lipid metabolism model,66 compounds isloated from Gouzhui,Washanzhui and Tianchu were screened.As a result,Gouzhui No.7,13,14,15 and 16,Washanzhui No.4,and Tianchu No.3,5,6,11,13,26,27,30,31,42,and 43 showed certain activity to reduce worm lipid.Gouzhui No.7,13 and 16 as well as Tianchu No.11 and 42 were further confirmed as the active compounds with the activity of fat-reducing.Among these compounds,Gouzhui No.7 showed the highest activity,which reduced the lipid accumulation by 34%.In conclusion,one crude extraction from sugarcane leaves with lifespan extending activity and 5 componds with fat-reducing activity were identified.Also,4 ketone A-resistant mutants were obtained.Our results provide not only clues for investigation of the mechanisms in lifespan extension,lipid control and nematicide,but also candidate compunds for the future applications in human health and agriculture.