ABSTRACT
Aim To investigate the mechanism by which ginsenoside Rgl regulates autophagy anrl delays brain aging in mice through AMPK/mTOR signaling pathway.Methods C57BL/6J male mice were ran¬domly divided into four groups, namely brain aging model group ,control group, Rgl anti-aging group,auto¬phagy activator Rapamycin anti-aging group.After the modeling was completed, the test of each experimental index would be carried out on the next day.Morris wa¬ter maze experiment was used to detect the learning and memory ability of mice.Paraffin sections of the hippocampus were prepared, HE , Nissl and immunohis- tochemical staining were used to observe the morpholo¬gy of hippocampal neurons, the number of neurons and Nissl bodies was counted, and autophagy-related proteins p62 , ATG5 , ULK1 were detected.Brain tissue homogenates were prepared to detect the aetivity of brain tissue acetylcholinesterase ( AChE ).Western blot was userl to detect brain tissue autophagy-related proteins LC3II, P62, beclinl, P-AMPK/AMPK, P- mTOR/mTOR and apoptosis protein P53.Results Water maze test showed that Rgl and Hap significantly improved the learning and memory abilities of brain-ag¬ing mice.HE and Nissl staining showed that Rgl and Rap decreased necrotic cells and increased the number of Nissl bodies in the hippocampus of brain-aging mice.Immunohistochemistry staining showed that Rgl and Rap decreased the expression of neuronal autoph- agv protein P62 in hippocampus and increased the ex-pression of ATG5 and ULK1.Rgl and Rap decreased the activity of AhcE in brain-aging mice.Western blot showed that Rgl and Rap increased autophagy-related proteins LC3II, Beclinl , P-AMPK/AMPK, but de¬creased the expression of P-mTOR/mTOR, P62, P53.Conclusions Ginsenoside Rgl can effectively antago¬nize the aging effect of D-gal on mouse brain.The pos¬sible mechanism is related to the regulation of autoph- agv by Rgl through AMPK/mTOR signaling pathway.
ABSTRACT
Neurodegenerative disease is common and frequently occurs in elderly patients. Previous studies have shown that ginsenoside Rg1 was able to inhibit senescent of brain, but the mechanism on the brain during the treatment remains elucidated. To study the mechanism of ginsenoside Rg1 in the process of anti-aging of brain, forty male SD rats were randomly divided into normal group, Rg1 normal group, brain aging model group and Rg1 brain aging model group, each group with 10 rats (brain aging model group: subcutaneous injection of D-galactose (120 mg kg(-1)), qd for 42 consecutive days; Rg1 brain aging model group: while copying the same test as that of brain aging model group, begin intraperitoneal injection of ginsenosides Rg1 (20 mg x kg(-1)) qd for 27 d from 16 d. Rg1 normal group: subcutaneous injection of the same amount of saline; begin intraperitoneal injection of ginsenosides Rg1 (20 mg x kg(-1)) qd for 27 d from 16 d. Normal: injected with an equal volume of saline within the same time. Perform the related experiment on the second day after finishing copying the model or the completion of the first two days of drug injections). Learning and memory abilities were measured by Morris water maze. The number of senescent cells was detected by SA-beta-Gal staining while the level of IL-1 and IL-6 proinflammatory cytokines in hippocampus were detected by ELISA. The activities of SOD, contents of GSH in hippo- campus were quantified by chromatometry. The change of telomerase activities and telomerase length were performed by TRAP-PCR and southern blotting assay, respectively. It is pointed that, in brain aging model group, the spatial learning and memory capacities were weaken, SA-beta-Gal positive granules increased in section of brain tissue, the activity of antioxidant enzyme SOD and the contents of GSH decreased in hippocampus, the level of IL-1 and IL-6 increased in hippocampus, while the length of telomere and the activity of telomerase decreased in hippocampus. Rats of Rg1 brain aging group had their spatial learning and memory capacities enhanced, SA-beta-Gal positive granules in section of brain tissue decreased, the activity of antioxidant enzyme SOD and the contents of GSH increased in hippocampus, the level of IL-1 and IL-6 in hippocampus decreased, the length contraction of telomere suppressed while the change of telomerase activity increased in hippocampus. Compared with that of normal group, the spatial learning and memory capacities were enhanced in Rg1 normal group, SA-beta-Gal positive granules in section of brain tissue decreased in Rg1 normal group, the level of IL-1 and IL-6 in hippocampus decreased in Rg1 normal group. The results indicated that improvement of antioxidant ability, regulating the level of proinflammatory cytokines and regulation of telomerase system may be the underlying anti-aging mechanism of Ginsenoside Rg1.