Blood-brain barrier permeability of Gualou Guizhi granules and neuroprotective effects in ischemia/reperfusion injury.

The present study aimed to estimate the blood-brain barrier (BBB) permeability of Gualou Guizhi granules (GLGZG) in normal rats and in rat models of ischemia/reperfusion (I/R) injury, and to examine the neuroprotective effects of GLGZG. A sensitive high‑performance liquid chromatography-quadrupole-time of flight-mass spectrometry analytical method was developed to determinate the components of GLGZG in the plasma and brain tissue. Middle cerebral artery occlusion (MCAO) in rats served as a model of in vivo I/R. Citrulline, gallic acid, albiflorin, peoniflorin, liquiritin apioside, liquiritin, isoliquiritin apioside, isoliquiritin, liquiritigenin, isoliquiritigenin and glycyrrhizinic acid rapidly passed into the bloodstream. Citrulline, albiflorin, peoniflorin, liquiritin apioside, liquiritin, liquiritigenin, isoliquiritigenin and glycyrrhizinic acid also passed the BBB and reached the brain tissue of MCAO rats, while isoliquiritigenin and glycyrrhizinic acid were not detected in the brain tissue of the normal rats. The potential neuroprotective effect of GLGZG was determined in MCAO rats. The intragastric administration of GLGZG following reperfusion of rats for 2 h decreased the neurological defects and infarction volume, attenuated pathological changes of brain tissue and exerted a significant protective effect in cerebral ischemia injury. In conclusion, certain components of GLGZG passed through the BBB, particularly following cerebral ischemia injury, and this may be therapeutically effective for the treatment of cerebral ischemia injury in the human brain.