Study On Anti-senescent Activity And Its Mechanism Of Maythorn Flavanol

China as well as many other countries are confronted with serious challenges fromaging of population, thus broad concerns have been raised on researches of senility and itsmechanism. Based on the free radical theory, this thesis conducted in vivo experiments toexplore the anti-senescent activity of Maythorn flavanol (MF) and probable explanations,in order to offer more data for new functional food development.Methods:(1) Anti-senescent activity of MF in Drosophila melanogaster was investigatedaccording to the following methods. The survival test was employed to observe MF’seffects on mean life span, maximum life span and mortality-time curve of male and femaledrosophila. And biochemical indicators of male and female drosophila after30d’sadministration were used to evaluate MF’s anti-oxidant capacity.(2) MF’s protecting function against D-galactose-induced per-oxidative damage inmouse was evaluated. Via the process of establishing oxidative damage model byhypodermic injection of D-galactose, MF of different doses were orally given to mice atthe same time for consecutive49d. Anti-oxidant profiles (SOD, GSH-Px), lipidper-oxidation product (MDA) in mouse serum and organs, and senescent-related enzyme(MAO) in mouse brain and liver were examined, in order to assess MF’s ability ofpreventing oxidation and senescence induced by D-galactose.(3) MF’s capability of improving anti-oxidant level in senescent mouse was appraised.Senescent mouse model was established by hypodermic injection of D-galactose at first,and then MF were offered to mice by oral administration for consecutive35days (injectioncontinued within this period）. Anti-oxidant system activity (SOD, GSH-Px), lipidper-oxidation product (MDA) in mouse serum and organs, senescent-related enzyme(MAO) in mouse brain and liver, ATPase (Na+K+ATPase) in brain were detected, so as toinvestigate MF’s function of recovering anti-oxidant stage in aged animals.Results:(1) MF’s displayed anti-senescent activity in drosophila. MF improved mean life spanand maximum life span of male and female drosophila along with deferred their50%lethaltime;0.2%and0.8%doses had significant life span increasing activity, and performedbetter in female individuals; the average mean life span improving rate of the above2 doses in female drosophia were6.6%and7.2%，while5.3%and5.8%in male drosophila,maximum life span improving rate were5.8%and12.1%in female drosophia，and in maledrosophila were11.7%and10.2%as well. MF also increased SOD activity and decreaseMDA level in drosophila，the0.2%group performed the best，and female individuals weremore sensitive. The anti-senescent effects of MF may connect with its anti-oxidant activity.(2) MF’s effect on antagonizing D-galactose-induced peroxidative damage wasconfirmed. Simultaneously establishing model and giving antioxidants to mice showed MFand positive control (100mg/kg.bw vitamin C) had resisted against the process ofoxidative damage caused by D-galactose injection. Results turned out to be divergent whentreated with different doses of MF or vitamin C. After analysis of the mentionedparameters，60mg/kg.bw MF had partial anti-oxidant and anti-senescent activity，120mg/kg.bw MF had better and wider anti-oxidant and anti-senescent activity; MDAelimination effects in apparatuses were better when treated with60~120mg/kg.bw MFthan positive control，but positive control worked better in serum, and other indicatorsvaried with different samples.(3) MF’s influence on antioxidant activity in senescent mice was contributive.Providing MF to senile model mice would alleviate their senescent situation and amelioratetheir anti-oxidant profile.90~180mg/kg.bw MF had significant anti-oxidant activity insenescent animals’ serum and organs and improved brain Na+K+ATPase level, whilehighest dose had superior and broader effects.60mg/kg.bw MF lowered brain MAOactivity, while90~180mg/kg.bw MF reduced liver MAO activity. The optimal conditionof MF application still needs further research.