Effect Of Active Ingredients Of Traditional Chinese Medicine On Learning, Memory And Hippocampi Neurogenesis Of D-Gal-Induced Consenescence Mice

Objective:Danshen injection, Salvianolic acid B, total glycosides of Herba Cistanche and ginsenoside Rgl interventions were applied to D-gal-induced consenescence mice. Changes of learning and memory ability, discrepancy of hippocampi cells proliferation and neural stem cells differentiation, antioxidant capacity and oxidative damage in body and local hippocampi tissue as well as neurokine in hippocampi tissue were inspected to observe the effect of active ingredients of traditional Chinese medicine on leaning, memory and neurogenesis of D-gal-induced consenescence mice.Methods:1. In the experiment to study salvia miltiorrhizae’s influence on the D-gal-induced learning and memory capacity of senile mice, 2-3-month-aged male BALB/c mice were randomly divided into 3 groups:A. control group; B. model group; C. salvia miltiorrhizae group. Each group consisted 8 mice. Senile model were made by subcutaneous injection of D-gal for 42 days. From the 15th day, normal saline and salvia miltiorrhizae injection were intraperitoneal injected to the mice. At the 43th day, water maze test was conducted.24h later, serum samples and hippocampus samples were taken to measure the SOD (superoxide dismutase) and MDA (methylene dioxyamphetamine) content in the serum and hippocampus homogenate supernate. The antioxidant capacity and oxidative damage degree of mice were evaluated.2. In the experiment to study the influence of salvianolic acid B and GCs (general cistanosides) on D-gal-induced learning and memory capacity of senile mice and hippocampus neurogenesis,3-month-aged Nestin-GFP mice were randomly divided into 7 groups:A. control group; B. model group; C. low-dose salvianolic acid B group; D. high-dose salvianolic acid B group; E. low-dose GCs (general cistanosides) group; F. high-dose GCs (general cistanosides) group; G VE group. Each group consisted 6 mice. Senile model were made by subcutaneous injection of D-gal for 42days. From the 15th day, medicines were intraperitoneal injectied to the corresponding mice. At the 43 th day, water maze test was conducted.24h later,6 serum samples and 6 hippocampus samples of each group were taken to measure the SOD and MDA content in the serum and hippocampus homogenate supernate (the brains were sagittally divided into 2 hemispheres.The right halfs were used to separate the hippocampus and the left hemispheres were froozed in liquid nitrogen).Content of BDNF and GDNF in the hippocampus of mice were checked too. The frozen left hemispheres were cut into continuous frozen sections to observe the proliferation of hippocampus cells and the differentiation of neural stem cells by immumofluorescence method.3. In the experiment to study the therapeutic effect of Ginsenoside Rgl and GCs (general cistanosides) on D-gal-induced learning and memory capacity of senile mice and hippocampus neurogenesis,3-month-aged Nestin-GFP mice were randomly divided into 5 groups:A. control group; B. model group; C. Ginsenoside Rgl; D. GCs group; E. VE group. Each group consisted 6 mice. Senile model were made by subcutaneous injection of D-gal for 42days. After that medicines were intraperitoneal injectied to the corresponding mice for 30 days. At the 73 th day, water maze test was conducted.24h later,6 serum samples and 6 hippocampus samples of each group are taken to measure the SOD and MDA content in the serum and hippocampus homogenate supernate (the brains were sagittally divided into 2 hemispheres.The right halfs were used to separate the hippocampus and the left hemispheres were froozed at liquid nitrogen).The content of BDNF and GDNF in the hippocampus of mice were checked too. The frozen left hemispheres were cut into continuous frozen sections to observe the proliferation of hippocampus cells and the differentiation of neural stem cells by immumofluorescence method.Results:1. In the first part of mice in model group showed less platform crosses and longer escape latent period compared with control group and activity of SOD in serum and hippocampus decreased and MDA contents were increased in model group (P<0.01). Compared with model group, the number of platform crosses increased and the escape latency was significantly dicreased in salvia miltiorrhizae group (P<0.05) while the activity of SOD、MDA contents were improved in salvia miltiorrhizae group (P<0.05).2. In the second part of experiment, compared with control group, mice in model group showed ①less platform crosses and longer escape latent period (P<0.05);②lower SOD activity in the serum and hippocampus and higher MDA content (P《0.05);sna less number of SGZ Nestin+cells, PCNA+ cells and DCX+ cells in hippocampus as well as β-Ⅲtubulin+ cells in DG zone of hippocampus and more SGZ GFAP+ cells (P<0.05);④ lower content of BDNF and GDNF in hippocampus of mice. When compared with the modol group, mice in salvianolic acid B group and GCs group showed ① more platform crosses and shorter escape latent period (P<0.05);② higher SOD activity and lower MDA content (P<0.05);③ more SGZ Nestin+ cells, PCNA+ cells, DCX+ cells and P-IIItubulin+ cells and less GFAP+ cells (P<0.05);④ higher content of BDNF and GDNF in hippocampus (P<0.05).3.In the third part of experiment, compared with the control group,mice in model group showed ①less platform crosses and much longer escape latent period (P<0.05);②SOD activity in serum and hippocampus in model group was lower and MDA content was higher (P<0.05);③less SGZ Nestin+cells, PCNA+ cells and DCX+ cells in hippocampus as well as β-Ⅲtubulin+ cells in DG zone more SGZ GFAP+ cells (P<0.05);④ lower content of BDNF and GDNF in hippocampus of mice (P<0.05). When compared with the model group, mice in Ginsenoside Rgl group and GCs group showed ①more trenceplatform crosses (no significance) and shorter escape latent period (P<0.05);② higher SOD activity and lower MDA content in plasma and hippocampus (P<0.05);③ more SGZ Nestin+ cells, PCNA+ cells, DCX+ cells and p-IIItubulin+ cells and less GFAP+cells (P<0.05);④ higher content of BDNF and GDNF in hippocampus of mice (P<0.05).Conclusion:1.Salvia miltiorrhizae injection could alleviate the decline of the learning and memory ability of senile mice.The mechanism might related to its ability of scavenging free radicals and maintaining free radical balance in the micro-environment.2.Intervention of salvianolic acid B and GCs could alleviate the decline of the learning and memory ability of senile mice. The mechanism might related to its ability of improving organismic antioxidation, scavenging free radicals, maintaining organismic internal environment, promoting the secretion of neurotrophin in brain as well as maintaining and facilitating neurogenesis.3.Theraputic injection of ginsenoside Rgl and GCs to the senile model D-gal mice could enhance the antioxidation of senile organism, scavenge free radicals in the organism, regulate the secretion of relevant factors in the microenvironment and maintain and facilitate neurogenesis. These alleviated the decline of the learning and memory function during the senescence period.