(+)-Borneol is neuroprotective against permanent cerebral ischemia in rats by suppressing production of proinflammatory cytokines

Stroke is one of the leading causes of disability and death globally. It occurs when a major artery is occluded in the brain and leads to death of cells within the injured tissue. (+)-Borneol, a simple bicyclic monoterpene extracted from traditional Chinese medicine, is widely used in various types of diseases. However, no study has proved the effects of (+)-borneol on functional recovery from permanent ischemic stroke and the mechanism is still unknown. Here, we report that in the rat model of permanent cerebral ischemia, we found that (+)-borneol (1.0 mg/kg) significantly ameliorated infarct size and neurological scoresvia reducing the expression of inducible nitric oxide synthase (iNOS) and tumor necrosis factor-alpha (TNF-α) in a dose dependent manner. Notably, (+)-borneol showed long-term effects on the improvement of sensorimotor functions in the photothrombotic model of stroke, which decreased the number of foot faults in the grid-walking task and forelimb asymmetry scores in the cylinder task, at least in part through reducing loss of dendritic spines in the length, brunch number and density. These findings suggest that (+)-borneol could serve as a therapeutic target for ischemic stroke.