title: The protective role of Tongxinluo on blood-brain barrier after ischemia-reperfusion brain injury.
abstract: BACKGROUND
  Tongxinluo (TXL), a renowned traditional Chinese medicine, consists of several different kinds of ingredients and has been widely used to treat myocardial infarction and ischemic stroke. However, the underlying neuroprotective mechanisms are not fully understood.
  
  
  OBJECTIVE
  We focus on the effect of TXL on blood-brain barrier (BBB) including edema formation and tight junction (TJ) protein rearrangement, and inflammatory response after transient middle cerebral artery occlusion (tMCAO). We further explore the protective mechanism of TXL on ischemia-induced BBB damage.
  
  
  METHODS
  Adult CD1 male mice (n=168) were randomly divided into TXL pre-treatment group, TXL pre-post treatment group, TXL post-treatment group, control group and sham group. Mice in TXL pre-treatment group were given TXL solution by 1g/kg/day orally for 7 days before tMCAO. Mice in pre-post treatment group were continuously given TXL 7 days before and 14 days after tMCAO. Mice in TXL post-treatment group were given TXL solution immediately after tMCAO. Rotarod test and neurological severity scores were evaluated at 1-14 days following tMCAO. Brains were harvested for examining infarct volume, edema formation, and immunofluorescent staining at 1 and 3 days after tMCAO. Cytokines IL-6, IL-1β and TNF-α mRNA expression, and BBB permeability were further examined by RT-PCR and immunostaining.
  
  
  RESULTS
  TXL pre-post treatment improved neurobehavioral outcomes and reduced infarct volume compared to the control (p<0.05). Meanwhile, hemispheric swelling, Evans blue and IgG protein extravasation reduced, while TJ protein expression up-regulated in pre-post treatment group (p<0.05). Further study indicated that infarct volume was smaller and BBB damage was less severe in TXL pre-post treatment group compared to TXL pre-treatment alone. It was noted that fewer myeloperoxidase (MPO) positive cells and less cytokines IL-6, IL-1β and TNF-α expression in pre-post treatment group compared to the control group (p<0.05).
  
  
  CONCLUSIONS
  TXL pre-treatment and pre-post treatment effectively protected the brain from BBB disruption via alleviating inflammatory response. Moreover, pre-post treatment has better outcomes, suggesting that continuous administration of TXL before and throughout ischemia period is necessary because of multiple functions of TXL.
authors.affiliation: Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Liu
authors.forename: Guang Hui
authors.initials: GH
authors.lastname: Tang
authors.forename: Yu Hao
authors.initials: YH
authors.lastname: Sun
authors.forename: Xiao Jie
authors.initials: XJ
authors.lastname: Lin
authors.forename: Cong
authors.initials: C
authors.lastname: Wei
authors.forename: Guo-Yuan
authors.initials: GY
authors.lastname: Yang
authors.forename: Jian Rong
authors.initials: JR
authors.lastname: Liu
mesh_terms: D000818:Animals; D001812:Blood-Brain Barrier / Q000187:drug effects* / Q000378:metabolism; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D001929:Brain Edema / Q000188:drug therapy; D002545:Brain Ischemia / Q000188:drug therapy* / Q000378:metabolism; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D020244:Infarction, Middle Cerebral Artery / Q000188:drug therapy / Q000378:metabolism; D007249:Inflammation / Q000188:drug therapy / Q000378:metabolism; D053583:Interleukin-1beta / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D007962:Leukocytes / Q000187:drug effects / Q000378:metabolism; D008297:Male; D051379:Mice; D018696:Neuroprotective Agents / Q000494:pharmacology*; D011897:Random Allocation; D015427:Reperfusion Injury / Q000188:drug therapy* / Q000378:metabolism; D019108:Tight Junctions / Q000187:drug effects / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D004365:Drugs, Chinese Herbal; D053583:Interleukin-1beta; D015850:Interleukin-6; D018696:Neuroprotective Agents; D014409:Tumor Necrosis Factor-alpha; C513941:tongxinluo