Lycium Barbarum polysaccharides ameliorates hyperglycemia-exacerbated cerebral ischemia/reperfusion injury via protecting blood-brain barrier

•The hyperglycemia exacerbates cerebral ischemia / reperfusion injury.•Pretreatment with LBP could decrease hyperglycemia deteriorated cerebral injury induced by ischemia / reperfusion.•The protection of blood-brain barrier was involved in LBP pretreatment decreased the hyperglycemia exacerbated brain damage following ischemia / reperfusion.