Effects of scalp electroacupuncture on the PI3K/Akt signalling pathway and apoptosis of hippocampal neurons in a rat model of cerebral palsy.

Abstract

Background Substantial evidence from clinical reports has established that most cerebral palsy (CP) patients benefit from a comprehensive rehabilitation exercise training programme. Such advances are enhanced when scalp electroacupuncture (EA), applied at a location corresponding to the projection of the motor area, is combined with rehabilitation exercise training. However, little information exists regarding the mechanistic basis for these effects. Objective To examine whether EA stimulation within the scalp projection location of the motor area can inhibit apoptosis of hippocampal neurons by regulating the PI3k/Akt signalling pathway in a rat model of CP. Methods Fifty male Sprague-Dawley rats underwent surgical modelling of CP. Five were used to confirm successful establishment of the model and the remaining 45 rats were randomly divided into one of three groups that remained untreated (CP group, n=15) or received EA treatment alone (CP+EA group, n=15) or EA in combination with a PI3K/Akt inhibitor (CP+EA+LY294002 group, n=15)). An otherwise healthy negative control group of rats undergoing sham surgery was also included (Control group, n=15). In the CP+EA and CP+EA+LY294002 groups, EA was applied to the scalp surface at alocation corresponding to the projection of the motor area. Basso, Beattie and Bresnahan (BBB) locomotor scores, hippocampal protein expression of Akt and p-Akt (by Western blot analysis) and neuronal apoptosis in hippocampal tissue (by histopathology) were assessed at 7, 14 and 21 days post-CP induction. Results CP rats receiving scalp EA treatment demonstrated improved behavioural scores, less hippocampal neuronal apoptosis and higher expression levels of Akt and p-Akt (p<0.05) at all time points studied compared with untreated CP rats. There were no significant differences observed between CP+EA+LY294002 and untreated CP model groups. Conclusions The effects of scalp EA on the PI3K/ Akt signalling pathway may represent one of the mechanisms involved in the inhibition of hippocampal neuronal apoptosis and improvement of deficits associated with CP in a rat model.