Anti-aging Function And Molecular Mechanism Of The Major Roval Jelly Proteins

With the acceleration of population aging world widely,the demand of anti-aging functional food is increasing in the international market.Royal Jelly(RJ),as an internationally recognized traditional anti-aging functional food,will play a more important role.According to the recent studies,the Main Royal Jelly Proteins(MRJPs)family is the key constituent of RJ.However,it is still unclear whether the anti-aging function and mechanism of RJ affect the mammals.This study focused on the activity of Lyophilized MRJPs prepared by ultrafiltration from Fresh RJ.The anti-aging experiment with the corresponding mechanism was carried out based on naturally aged rats and human cell lines,and the results are as follows:1.The effect of anti-aging function and molecular mechanism from MRJPs on ratSDS-PAGE showed that molecular weight of MRJPs was in 49-80 kDa,and its amino acid composition was similar to that of casein,suggesting the biological activity of MRJPs was reflected on some special forms instead of the amino acid level.MRJPs have no significant impact on the body weight and organ index of aged rat.Index of the epididymis and testicle of aged rat were significantly lower than that of youth groups,and the degradation of this index could not be improved through oral MRJPs.The result from HE staining showed that MRJPs significantly improved pathologic features of liver and kidney caused by aging.In addition.MRJPs significantly enhanced the activity of CAT in the blood(P<0.05),and decreased the MDA levels of blood.The regulation of GSH content and GSH-PX activity were similar with young rats,indicating its good antioxidant activity.There was a positive correlation between mTOR transcription level and MRJPs intervention dose.S6 kinase was activated through mTOR pathway in this experiment.The mTOR transcription level of young rat was significantly higher than that of old control,and mTOR transcription level of old control was improved by MRJPs.The similar phenomenon has also been found on s6k.Transcription level of Foxol in young rats was significantly higher than that of control.However.this level from old rat could be improved by MRJPs,indicating anti-aging effect.In addition,MRJPs significantly improved the transcription of telomerase reverse transcriptase(TERT)in rat blood,suggesting the anti-aging mechanism was associated with the TERT.There was no statistically difference on the transcription levels of sod1 after treated by MRJPs.2.Memory improving effects of MRJPsMorris water maze showed that MRJPs can significantly improve spatial cognitive ability in aged rats.Escape latency of MRJPs group were reduced 48.5%(P=0.0045)and 49.9%(P=0.0036)compared with the control group and the casein group respectively.Crossings of MRJPs group were increased 177.4%and 46.1%compared with the control group and the casein group respectively,indicating the effects that MRJPs can significantly improved spatial memory in rats.Based on Ultra performance liquid chromatography quadrupole time of flight mass spectrometry(UPLC-QTOF/MS),rat urine fingerprints showed that metabolites of MRJPs groups rats has a tendency to regress to the young group.Total 28 age related biological markers were identificated,of which 6 has significantly change after MRJPs intervention,namely,Nicotinic acid mononucleotid(1),Selenocystathionine(2),CDP-ethanolamine(3),Cysteic acid(4),Phosphoenolpyruvic acid(5),and Xanthosine(6).Combining with the results of literature analysis,MRJPs from RJ might be a new potential supplemental protein to improve cognitive performance.3.Protection effects of MRJPs and KHCO3 on rat bone mineral densityMRJPs and KHCO3 have no effect on the body weight.Liver function test showed that MRJPs is a safe dietary supplements,and it has certain regulation on liver function.MRJPs lead to a slightly decrease of bone mineral density(BMD)with a possible mechanism by losing of urine calcium and reducing the estrogen.KHCO3(100 mg/mL)protected bone from osteoporosis,and reduced estradiol level.However the antagonism was abserved on C2C12 after treated by MRJPs and estradiol,indicating the protection was achieved by reducing the antagonism.MRJPs and KHCO3 showed its antioxidation activity by reducing MDA and protein carbonyl content as well as improving the GSH level.They reduced CTX-I to some extent,significantly increased type I original collagen(PINP)and OPG content.Supplement of 100 mg/mL KHCO3 has the similar effect.Clock,cry1,cry2 were upregulated and the bmall was downregulated by MRJPs and estradiol,indicating the effect of circadian rhythm on BMD.4.Anti-aging function of MRJPs on MRC-5 cell lineProliferation effect was not obvious on middle aged MRC-5 cells with 25-200 ?g/mL MRJPs,which verifed by the flow cytometry as the proliferation index without significant difference among all the groups.But MRJPs significantly promoted the proliferation of aged human embryonic lung cells MRC-5 cells.?-galactosidase activity detection showed that MRJPs significantly reduced the proportion of aged MRC-5 cells with a dose-dependent manner.Raman detection showed no difference Raman characteristic peak between MRJPs and casein except peak in 683 cm-1,which reflect its protein generality.