A Novel Extract From Ginkgo biloba Inhibits Neuroinflammation and Maintains White Matter Integrity in Experimental Stroke

biloba L. leaf extract (GBE) has been added in many commercial herbal formulations such as EGb 761 and Shuxuening Injection to treat cardiovascular diseases and stroke worldwide. However, the comprehensive effects of GBE on cerebral ischemia remained unclear. Using a novel GBE (nGBE), which consists of all the compounds of traditional (t)GBE and one new compound, pinitol, we investigated its effect on inflammation, white matter integrity, and long-term neurological function in an experimental stroke model. Both transient middle cerebral artery occlusion (MCAO) and distal MCAO were conducted in male C57/BL6 mice. We found that nGBE significantly reduced infarct volume at 1, 3, and 14 days after ischemia. Sensorimotor and cognitive functions were superior in nGBE treated mice after MCAO. nGBE inhibited the release of IL-1b in the brain, promoted microglial ramification, and regulated the microglial M1 to M2 phenotype shift at 7 days post injury. In vitro analyses showed that nGBE treatment reduced the production of IL-1b and TNFa in primary microglia. Administration of nGBE also decreased the SMI-32/MBP ratio and enhanced myelin integrity, thus exhibiting improved white matter integrity at 28 days post stroke. These findings demonstrate that nGBE protects against cerebral ischemia by inhibiting microglia-related inflammation and promoting white matter repair, suggesting that nGBE is a promising therapeutic strategy for long-term recovery after stroke.& COPY; 2023 IBRO. Published by Elsevier Ltd. All rights reserved.

Automated summary

The comprehensive effects of Ginkgo biloba L. leaf extract (GBE) on cerebral ischemia remained unclear. This study investigated the effect of a novel GBE (nGBE) on inflammation, white matter integrity, and long-term neurological function in an experimental stroke model. The results showed that nGBE significantly reduced infarct volume, improved sensorimotor and cognitive functions, inhibited microglia-related inflammation, and promoted white matter repair.