Protective effects and mechanism of total coptis alkaloids on a beta 25-35 induced learning and memory dysfunction in rats.

Objective: To observe the effect of total coptis alkaloids (TCA) on beta -amyloid peptide (A beta 25-35) induced learning and memory dysfunction in rats, and to explore its mechanism.

Methods: Forty male Wistar rats were randomly divided into four groups: the control group, the model group, the TCA low dose (60 mg/kg) group and the TCA high dose (120 mg/kg) group, 10 in each. A beta 25-35 (5microl, 2 microg/microl) was injected into bilateral hippocampi of each rat to induce learning and memory dysfunction.

Protective effect of ecdysterone on PC12 cells cytotoxicity induced by beta-amyloid25-35.

Objective: To examine the protective effect of ecdysterone (ECR) against beta-amyloid peptide fragment(25-35) (Abeta(25-35))-induced PC12 cells cytotoxicity, and to further explore its mechanism.

Methods: Experimental PC12 cells were divided into the Abeta group (treated by Abeta(25-35) 100 micromol/L), the blank group (untreated), the positive control group (treated by Vit E 100 micromol/L after induction) and the ECR treated groups (treated by ECR with different concentrations of 1, 50 and 100 micromol/L). The damaged and survival condition of PC12 cells in various groups was monitored by lactate dehydrogenase (LDH) release and MTT assay.

[The effects of genistein on epidermal growth factor receptor mediated signal transduction pathway in human ovarian carcinoma cells lines SKOV3 and its xenograft in nude mice].

Objective: It was reported previously that genistein could inhibit proliferation of human ovarian carcinoma cell line SKOV(3), but mechanism was not clear. There is a close relationship between EGFR mediated signal transduction pathway and the development of ovarian tumor. This study aimed to investigate the effects of genistein on the EGFR mediated signal transduction pathway and to clarify its mechanisms of proliferation inhibition on human ovarian carcinoma cell line SKOV(3) and its xenograft in nude mice.

[Effect of ecdysterone on the expression of c-fos in the brain of rats induced by microinjection beta-AP25-35 into the hippocampus].

Aim: To observe the behavior in learning and memory and the expression of c-fos gene from the brain of rats induced by beta-AP25-35, and the intervention of ecdysterone, in order to explore the protective mechanism of ecdysterone on the dysfunction of learning and memory of the rat induced by beta-AP25-35.

Methods: Microinjection of beta-AP25-35 into hippocampus induced learning and memory dysfunction of rats. The learning and memory of rats were observed by Morris Water Maze.