Ginsenoside Rgl regulates autophagy through AMPK/mTOR signaling pathway and delays brain aging in mice / 中国药理学通报

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.

Research progress on autophagy-related protein 5 and BECLIN-1 regulate autophagy and apoptosis / 中国人兽共患病学报

ATG5 and BECLIN-1 belong to two kind of crucial autophagy-related proteins included the formation of autoph-agosomes,in addition to the promotion of autophagy,enhances susceptibility towards apoptotic stimuli,therefore,ATG5 and BECLIN-1 are considered to be a molecular link between autophagy and apoptosis.Preliminary data revealed that ATG5 media-ted the formation of autophagosomes by ATG5-ATG12-ATG16L ubiquitination system,while BECLIN-1 induces autophagy by phosphatidylino3-kinase (PtdIns3KC3)complex.But now it is believed that truncated ATG5(tATG5-N)and truncated BEC-LIN-1(BECLIN-1-C),an amino-terminal cleavage product of ATG5 and carboxyl-terminal cleavage product of BECLIN-1, could induce apoptosis.The research summarize the progress on ATG5 and BECLIN-1 regulated autophagy and apoptosis,so as to further reveal the molecular mechanism of they regulate autophagy and apoptosis.

Asiatic acid induces apoptosis in T98 G human glioblastoma cells by changing autophagy / 中国药理学通报

Aim To investigate the effect of asiatic acid on apoptosis and autophagy in human glioblastoma T98G cells. Methods MTT colorimetry was employed to assay the cellular proliferating activity. The fluores-cence microscope and Hoechst 33258 staining were used to detect the morphological changes. The cell ap-optosis and autophagy were analyzed by flow cytometry with Annexin-V/7-AAD and MDC staining respective-ly. The expressions of associated proteins were detected by Western blot to analyze the mechanism of apoptosis and autophagy. Results MTT assay showed that the growth of T 9 8 G cells was inhibited by asiatic acid ( IC50 =46. 3 μmol · L-1 ) . Annexin V/7-AAD stai-ning and Western blot revealed that asiatic acid in-duced apoptosis in T98 G cells by reducing the expres-sion of Akt, decreasing the mitochondrial membrane potential, and increasing the expression of Caspase-3. MDC staining and Western blot showed that the per-centage of MDC-positive cells was decreased and the expressions of Beclin-1 , LC3-II and Atgs were inhibi-ted by asiatic acid treatment. 5 μmol·L-1 chloroquine was used to up-regulate the expressions of LC3-Ⅱand Beclin-1 . Asiatic acid-inhibited autophagy was blocked and the total apoptotic rate was reduced remarkably. Conclusion Asiatic acid suppresses T98 G cells pro-liferation by inducing apoptosis and inhibiting cell au-tophagy, and the very role of inhibiting autophagy could promote apoptosis to a certain extent.