title: Fisetin alleviates early brain injury following experimental subarachnoid hemorrhage in rats possibly by suppressing TLR 4/NF-κB signaling pathway.
abstract: Early brain injury (EBI) determines the unfavorable outcomes after subarachnoid hemorrhage (SAH). Fisetin, a natural flavonoid, has anti-inflammatory and neuroprotection properties in several brain injury models, but the role of fisetin on EBI following SAH remains unknown. Our study aimed to explore the effects of fisetin on EBI after SAH in rats. Adult male Sprague-Dawley rats were randomly divided into the sham and SAH groups, fisetin (25mg/kg or 50mg/kg) or equal volume of vehicle was given at 30min after SAH. Neurological scores and brain edema were assayed. The protein expression of toll-like receptor 4 (TLR 4), p65, ZO-1 and bcl-2 was examined by Western blot. TLR 4 and p65 were also assessed by immunohistochemistry (IHC). Enzyme-linked immunosorbent assay (ELISA) was performed to detect the production of pro-inflammatory cytokines. Terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end-labeling (TUNEL) was perform to assess neural cell apoptosis. High-dose (50mg/kg) fisetin significantly improved neurological function and reduced brain edema at both 24h and 72h after SAH. Remarkable reductions of TLR 4 expression and nuclear factor κB (NF-κB) translocation to nucleus were detected after fisetin treatment. In addition, fisetin significantly reduced the productions of pro-inflammatory cytokines, decreased neural cell apoptosis and increased the protein expression of ZO-1 and bcl-2. Our data provides the evidence for the first time that fisetin plays a protective role in EBI following SAH possibly by suppressing TLR 4/NF-κB mediated inflammatory pathway.
authors.affiliation: Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, Jiangsu Province, China.
authors.forename: Chen-hui
authors.initials: CH
authors.lastname: Zhou
authors.affiliation: Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, Jiangsu Province, China.
authors.forename: Chun-xi
authors.initials: CX
authors.lastname: Wang
authors.affiliation: Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, Jiangsu Province, China.
authors.forename: Guang-bin
authors.initials: GB
authors.lastname: Xie
authors.affiliation: Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, Jiangsu Province, China.
authors.forename: Ling-yun
authors.initials: LY
authors.lastname: Wu
authors.affiliation: Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, Jiangsu Province, China.
authors.forename: Yong-xiang
authors.initials: YX
authors.lastname: Wei
authors.affiliation: Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, Jiangsu Province, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, Jiangsu Province, China.
authors.forename: Hua-sheng
authors.initials: HS
authors.lastname: Zhang
authors.affiliation: Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, Jiangsu Province, China.
authors.forename: Chun-hua
authors.initials: CH
authors.lastname: Hang
authors.affiliation: Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, Jiangsu Province, China.
authors.forename: Meng-liang
authors.initials: ML
authors.lastname: Zhou
authors.affiliation: Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, Jiangsu Province, China. Electronic address: shijx52@hotmail.com.
authors.forename: Ji-xin
authors.initials: JX
authors.lastname: Shi
mesh_terms: D000818:Animals; D001930:Brain Injuries / Q000378:metabolism* / Q000473:pathology / Q000517:prevention & control; D005419:Flavonoids / Q000494:pharmacology / Q000627:therapeutic use*; D044948:Flavonols; D008297:Male; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D013345:Subarachnoid Hemorrhage / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D051197:Toll-Like Receptor 4 / Q000037:antagonists & inhibitors / Q000096:biosynthesis*
chemical_list: D005419:Flavonoids; D044948:Flavonols; D016328:NF-kappa B; C495347:Tlr4 protein, rat; D051197:Toll-Like Receptor 4; C017875:fisetin
keywords: Early brain injury; Fisetin; Nuclear factor κB; Subarachnoid hemorrhage; Toll-like receptor 4