OBJECTIVETo analyze the mechanism of neuroprotection of insulin and which blood glucose range was benefit for insulin exerting neuroprotective action.

DATA SOURCESThe study is based on the data from PubMed.

STUDY SELECTIONArticles were selected with the search terms "insulin", "blood glucose", "neuroprotection", "brain", "glycogen", "cerebral ischemia", "neuronal necrosis", "glutamate", "γ-aminobutyric acid".

RESULTSInsulin has neuroprotection. The mechanisms include the regulation of neurotransmitter, promoting glycogen synthesis, and inhibition of neuronal necrosis and apoptosis. Insulin could play its role in neuroprotection by avoiding hypoglycemia and hyperglycemia.

CONCLUSIONSIntermittent and long-term infusion insulin may be a benefit for patients with ischemic brain damage at blood glucose 6-9 mmol/L.