Study On The Mechanism Of Lilium Brownii F.E. Brown Var. Viridulum Baker In Stress Response In C.elegans

In recent years,as the environment deteriorates and work pressure becomes more stressful,people are exposed to more and more intrinsic and extrinsic stimuli.The nonspecific reactions that occur to these stimuli are called stress reactions.When the level of stress response exceeds the body’s ability to adapt,it can lead to a variety of diseases,Therefore,how to resist the stress response has received widespread attention.Arising from nature,natural active substances are widely distributed.Besides,they have various biological activities such as anti-radiation,anti-tumor and anti-inflammatory.The natural product Lilium brownii var.Viridulum(Lily)has been recorded for more than2000 years.Lily is not only a valuable flower,but also a traditional Chinese herb on the list of medicinal food sources in China.Due to the advantages of small size,transparent body and short life cycle,Caenorhabditis elegans(C.elegans)have been widely utilized in drug screening and other aspects.Therefore,C.elegans were used as a model while huperzine quinone and 35°C high temperature selected as stressors in this study to investigate the effects and mechanisms of Lily aqueous extract on the stress resistance.Besides,the network pharmacological analysis was also performed to predict the active components,targets of action and signaling pathways of lily that may exert anti-stress responses.First,we investigated the effects of lily aqueous extracts on nematode stress resistance and their mechanisms of action.Through oxidative stress experiments,the lily treatment at 20 mg/m L could significantly prolong the nematode life span.Among which,the optimal concentration of lily aqueous extracts was 20 mg/m L,which could prolong the average life span of nematodes by about 14.82%.Under oxidative stress conditions,the treatment of lily aqueous extracts reduced the level of free radicals in nematodes by increasing the expression of relevant antioxidant enzymes activity and superoxide dismutase SOD-3 in nematodes.Besides,we found that these effects were related to the insulin-like signaling pathway of nematodes.Then,the nuclear translocation of the transcription factor DAF-16 under oxidative stress was investigated using a transgenic TJ356 nematode strain.As a result,lily aqueous extract was proved to increase the cytosolic translocation of DAF-16 and upregulated the transcription of sod-3,a downstream target gene of DAF-16.Next,the role and mechanism of lily aqueous extract on nematodes in response to heat stress was deeply explored.Lily aqueous extract at 20 mg/m L could extend the average lifespan of nematodes under heat stress by about 17.63%.Using transgenic nematode strains CF1038 and PS3551 to perform heat stress treatment,the deletion of either DAF-16 or HSF-1 could not extend the lifespan under this stress,suggesting that the improvement of the resistance to heat stress after drug administration was related to the transcription factors DAF-16 and HSF-1 in nematodes.In addition,the lily aqueous extract treatment group could increase the expression of heat shock protein HSP-16.2 in nematodes and could promote the nuclear translocation of DAF-16,further upregulating the expression of hsp-70,a direct downstream target gene of HSF-1,and hsp-16.2,a common downstream target gene with DAF-16.The chemical composition of Chinese herbal medicines is complex,and network pharmacology can be used to map the "active ingredient-target-disease" network to find the targets and pathways that act on diseases.Meanwhile,network pharmacology could provide convenience for researches on the effects of different components of traditional Chinese medicine.Therefore,this paper uses network pharmacology as a tool to analyze and predict the active ingredients,target proteins and signaling pathways of lily that play anti-stress effects.The core targets are indeed involving in anti-stress responses,including responses to oxidative stress,Fox O signaling pathway,and responses to reactive oxygen species were confirmed.Combining with literatures,the main active ingredients of lily water extract,such as kaempferol and quercetin were confirmed to have anti-stress responses.In conclusion,this study found that the natural product lily has the ability to enhance the anti-stress response of C.elegans and is associated with the insulin-like signaling pathway.These results are also consistent with the predictive validation results through preliminary network pharmacological analysis.Therefore,this study provides a reference for further research and application of the herbal lily with social significance.