Study On The Mechanisms Of Ginsenoside Rb1 In Mice Brain And HUVECs Against Senescence

ObjectiveWith the economy developing, living standards improving and average life span increasing, aging has become the worldwide trend and major risk factor of many diseases, such as cardiovascular diseases, cancer and neurodegenerative disorders. Those diseases threaten human health badly. Thus, it’s vital for us to study on the senescence related mechanisms.It has been found that Ginseng has lots of medical values, protective for central nervous system, cardiovascular system, digestive system, immune system, endocrine system and urogenital system. Ginsenoside Rb1 is one of the ginsenoside monomers, which is ginseng’s main effective component.TOR is a key modulator of aging in evolutionarily divergent species. Deregulated m TOR(mammalian Target of Rapamycin,m TOR)signaling leads to aging and some disease in mammal models. Some anti-aging intervention,like dietary restriction, can increase life span in model organisms, by suppressing TOR activity. We have proved that Ginsenoside Rb1 can protect HUVECs against H2O2-induced senescence, and the possible mechanisms include antioxidative stress, anti- inflammation and modulating Sirt1/e NOS/NO axis.But the effect of Ginsenoside Rb1 on natural aging mice brain and cellular replicative senescence, as well as the relation between Rb1 and m TOR signaling, is still unknown.Based on the background, our study aims to solve the following questions: 1. Whether Rb1 could reverse the changes in natural aging mice brain and replicative senescent HUVECs? 2. If the anti-senescence function of Rb1 involves m TOR signaling?Methods1. The effect of Rb1 on natural aging mice brain: examined the MDA level, MAO-B activity, the protein expression of Plasminogen activator inhibitor 1(PAI-1), p-m TOR/ m TOR(Mammalian Target Of Rapamycin) and p-p70S6K/ p70S6 K.2. Established Replicative senescent model: Cellular senescence was evaluated by morphology changes, SA-β-gal and PAI-1 protein expression.3. The effect of Rb1 on Replicative senescent HUVECs: evaluated by morphology changes, SA-β-gal and PAI-1 expression.4. The effect of Rb1 on m TOR / p70S6 K signaling in senescent HUVECs: western blot were used to evaluate the protein expression of p-m TOR, m TOR, p-p70S6 K, p70S6 K.5. The effect of Rb1 on oxidative stress in senescent HUVECs: MDA level and SOD1 activity were detected by commercial kits.Results1. In the brains of old controls, MDA level, MAO-B activity, expression of PAI-1 protein, phosphorylation level of m TOR and its target p70S6 K protein increased, compared with young group.2. The MAO-B activity, m TOR phosphorylation and p70S6 K phosphorylation level were decreased in the brain of both Rb1 group mice; Furthermore, the MDA level and PAI-1 protein expression level of high-dose-group mice brain decreased significantly compared with old controls.3. Replicative senescent model was established when CPDL>16~26.4. 80μmol/L Rb1 showed a protective effect on senescent HUVECs.5. Rb1 reversed the over expression of m TOR/p70S6 K in senescent HUVECs.6. After treated by Rb1, cellular SOD1 activity were elevated and MDA production decreased.Conclusions1. Ginsenoside Rb1 can protect mice brain and HUVECs against senescence.2. The anti- senescent effect of Ginsenoside Rb1 in mice brain and HUVECs is associated with m TOR signaling.3. The anti- senescent effect of Ginsenoside Rb1 in HUVECs is associated with reversing oxidative stress.