Picroside ? Regulates JNK Signal Transduction To Protect The Cerebral Ischemic Injury In Rats

Objective To study the protective effect and mechanism of picroside ? on regulating c-Jun N-terminal kinase(JNK) signal transduction after cerebral ischemia injury in rats.Methods By inserting a monofilament threads into middle cerebral artery occlusion(MCAO) to establish focal cerebral ischemic models in 140 Wistar rats. All rats were randomly divided into five groups consisting of control group, model group, picroside group, LPS group and U0126 group, which group contained 6h, 12 h and 24 h subgroup.By modified neurological severity score points(m NSS) test to evaluated The neurobehavioral function. The structure and apoptotic cells were observed and counted by HE staining.and terminal deoxynucleotidyl transferase d UTP nick end labeling(TUNEL)assay. The expression of JNK protein in cortex were determined by the immunohistochemistry(IHC) and Western Blot(WB).Results In all rats with MCAO, the neurological behavioral malfunction appeared. The damage of neuron in model group was worsened, while the neurobehavioral function score, apoptotic cell index, the expression of JNK and the level of JNK m RNA increased significantly than those in control group.The neurological behavioral function in treatment and U0126 group was improved, the number of apoptotic cells and the expression of JNK decreased significantly than those in model group. In LPS group, at 6h the damage of neuron was the worst, JNK expressions were much higher than those in model group, later the damage was recovered slightly.Conclusion Picroside ? could reduce JNK signal transduction pathway to protect the neuron from the apoptosis and inflammation after MCAO injury in rats.