Neuroprotective mechanism of tetrahydroxystilbene glucoside on rats after cerebral ischemia-reperfusion

Abstract

To investigate the neuroprotective mechanism of tetrahydroxystilbene glucoside (TSG), a Chinese medicine, on rats after cerebral ischemia-reperfusion. A total of 96 Sprague-Dawley male rats were divided into 4 groups (n=24): a control group, an ischemia-reperfusion (I/R) model group, a low dose TSG [60 mg/(kg.d)]group, and a high dose TSG [120 mg/(kg.d)]group. After 6 days intragastric (ig) administration of TSG or natural saline (I/R group), reversible middle cerebral artery occlusion (MCAO) model was established by intraluminal suture technique. The rats of control group were operated on while the middle cerebral artery was not blocked. At 6 h, 24 h, 48 h, and 7 d after the reperfusion, behavior test was used to evaluate the neurological deficiency of each group. The protein expressions of nerve growth factor (NGF), growth associated protein (GAP)-43, and protein kinase A catalytic subunit (PKAc) in the cortex were measured by immunohistochemical method. Compared with the I/R group, the neurological defect scores of the 2 TSG groups were significantly lower except at 6 h after the reperfusion. Compared with the I/R group, the protein expression of NGF, GAP-43, and PKAc after the reperfusion of the 2 TSG groups increased significantly. The protein expression of NGF may increase when treated with TSG after cerebral ischemia-reperfusion, which activates the PKA pathway and increases the protein expression of GAP-43 that protects the neuron.