The Effect Of Oleanolic Acid On Caenorhabditis Elegans Lifespan And Its Molecular Mechanism

Oleanolic acid(OA),a naturally occurring pentacyclic triterpene.OA exists largely in food products,and is a constituent of the leaves and roots and other more than 120 plant species.It has been reported to possess a variety of pharmacological activities,including hepatoprotective effects,hypoglycemic effects,antiinflammatory,antitumor,antiviral,and antioxidant activities.In recent years,OA has received a lot of attention because of its potential as an antioxidant.But the effects of OA on longevity in vivo and its possible underlying molecular mechanisms have not been reported before.Objective: We elected Caenorhabditis elegans(C.elegans)as an in vivo model to evaluate the anti-aging effect of Oleanolic acid in and explore its underlying mechanisms.Methods: 1.Lifespan assay: Synchronized L4 larvae were treated with 0,100,200,300,and 600 ?M OA to evaluate its anti-aging effect and determined the optimal dosages of OA.2.Stress resistance assays: To determine whether OA has a correlation between oxidative stress resistance and lifespan extension,treated and untreated worms were subjected to paraquat oxidative stress and 36? heat stress.3.Analysis of reactive oxygen species(ROS): To explore whether OA treatment could delay the accumulation of aging-related cellular damage in C.elegans,we evaluated the free radical-scavenging abilities of OA.4.Pharyngeal pumping assay: Comparing the pharyngeal pumping of OA-treated worms and untreated worms on the 3rd,6th,and 10 th day of adulthood,to determine whether OA could leading to reduced food intake(calorie restriction,CR).5.daf-16(mgDf50)mutant lifespan assay:We used daf-16 loss-of-function mutant worms to investigate if the effects of OA on C.elegans were acting through daf-16.6.Subcellular daf-16 localization:Transgenic strain TJ356 were treated with 300 ?M OA and then detected the subcellular localization of daf-16.7.Quantitative real-time PCR: To further determine that OA did act on daf-16,we examined the effect of OA on the expression of sod-3,hsp-16.2 and ctl-1 by using quantitative real-time PCR.Results: 1.OA extends the lifespan of wild-type C.elegans.2.OA improves the stress resistance and reduces the intracellular ROS level in C.elegans.3.OA induces lifespan extension may not proceed through the CR mechanism.4.OA extends the lifespan in C.elegans is modulated by daf-16.Conclusion: In summary,we have reported here the longevity effect of OA and elucidated its potential underpinning mechanisms.Given that DAF-16/FoxO plays a central role in the regulation of aging from C.elegans to mammals,this work provides the first insights into the effect of OA on longevity and aging-related disease in humans.