Abstract: Abstract: Objective To explore the neuroprotective effects of β-Aescinate on brain edema in traumatic brain injury (TBI) mice. Method A total of 78 male SD rats (Sprague Dawley Rat) were randomly divided into three groups:sham-operation group (Sham), traumatic brain injury group (TBI), β-Aescinate group, with 18 rats in each. (n=26 per group). The Sham-operated animals were anesthetized and surgically prepared only,but were not induced by cortical contusion;TBI group and β-Aescinate group using eCCI establish TBI model after skullcap was carefully removed, TBI group only establish TBI model，but no deal with; The TBI model of β-Aescinate group was established, and thenβ-Aescinate (5 mg/kg body weight) via intraperitoneal injection,one times per 24 hours. Each of measurement was performed after 48 hours, Neurological function were evaluated by modified neurological severity scores (mNSS); SD rats were sacrificed at 24 h after TBI and stained using hematoxylin and eosin (H&E)(n=6); Additionally, the cerebral edema was evaluated from the water content of the brain tissue using the wet-to-dry weight ratio(n=10); and Evans Blue assay were performed to investigate the neurologic deficit, cer- ebral water content (n=8);and blood-brain barrier permeability (BBB) (n=4) ;and the of aquaporin 4 (AQP4) was measured by Western Blot assay(n=6).Result Compared with the Sham group, TBI group were shown to neurologic deficit ,and the brain water content and the of AQP4 were increased (all P<0.05).moreover，BBB permeability is destroyed. However, β-Aescinate could improve the neurological function, reduce the brain water content, and significantly decreased the of AQP4 compared with the TBI group (all P < 0.05) BBB permeability of each treatment group was also significantly improved (all P＜0.01). Conclusion These finding suggested that β-Aescinate could reduce cerebral edema and improve neurological outcome in SD rat after TBI to exert neuroprotection, through which reverses the high level of AQP4 protein.

Key words: escin, craniocerebral trauma, brain injuries, aquaporin 4, brain edema, β-aescinate