title: MKEY, a Peptide Inhibitor of CXCL4-CCL5 Heterodimer Formation, Protects Against Stroke in Mice.
abstract: MKEY, a synthetic cyclic peptide inhibitor of CXCL4-CCL5 heterodimer formation, has been shown to protect against atherosclerosis and aortic aneurysm formation by mediating inflammation, but whether it modulates neuroinflammation and brain injury has not been studied. We therefore studied the role of MKEY in stroke-induced brain injury in mice.
  
  
  
  MKEY was injected into mice after stroke with 60 minutes of middle cerebral artery occlusion. Infarct volume and neurological deficit scores were measured. Protein levels of CCL5 and its receptor CCR5 were detected by Western blot and fluorescence-activated cell sorting (FACS), respectively. Numbers of microglia-derived macrophages (MiMΦs) and monocyte-derived MΦs (MoMΦs) in the brain, and their subsets, based on the surface markers CD45, CD11b, CCR2, CX3CR1, and Ly6C, were analyzed by FACS. MΦs and neutrophil infiltration in the ischemic brain were stained with CD68 and myeloperoxidase (MPO), respectively, and assessed by immunofluorescent confocal microscopy. The results showed that expressions of CCL5 and its receptor CCR5, were increased in the ischemic brain after stroke. MKEY injection significantly reduced infarct sizes and improved neurological deficit scores measured 72 hours after stroke. In addition, MKEY injection inhibited the number of MoMΦs, but not MiMΦs, in the ischemic brain. Furthermore, MKEY inhibited protein expression levels of Ly6C,CCR2, and CX3CR1 on MoMΦs. Lastly, the confocal study also suggests that the number of CD68-positive MΦs and MPO-positive neutrophils was inhibited by MKEY injection.
  
  
  
  MKEY injection protects against stroke-induced brain injury, probably by inhibiting MoMΦ-mediated neuroinflammation.
authors.affiliation: Department of Neurosurgery, Stanford University, Stanford, CA Department of Anesthesiology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Yifang
authors.initials: Y
authors.lastname: Fan
authors.affiliation: Department of Neurosurgery, Stanford University, Stanford, CA Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Xiaoxing
authors.initials: X
authors.lastname: Xiong
authors.affiliation: Department of Neurosurgery, Stanford University, Stanford, CA.
authors.forename: Yongming
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Neurosurgery, Stanford University, Stanford, CA.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Yan
authors.affiliation: Department of Neurosurgery, Stanford University, Stanford, CA Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Jian
authors.affiliation: Department of Surgery, Stanford University, Stanford, CA.
authors.forename: Baohui
authors.initials: B
authors.lastname: Xu
authors.affiliation: Department of Neurosurgery, Stanford University, Stanford, CA hzhao@stanford.edu.
authors.forename: Heng
authors.initials: H
authors.lastname: Zhao
mesh_terms: D000818:Animals; D015153:Blotting, Western; D001921:Brain / Q000166:cytology / Q000187:drug effects*; D018946:Chemokine CCL5 / Q000187:drug effects* / Q000378:metabolism; D019281:Dimerization; D005434:Flow Cytometry; D020244:Infarction, Middle Cerebral Artery / Q000378:metabolism* / Q000503:physiopathology; D008264:Macrophages / Q000166:cytology / Q000187:drug effects*; D008297:Male; D051379:Mice; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D009504:Neutrophils / Q000166:cytology / Q000187:drug effects*; D010456:Peptides, Cyclic / Q000494:pharmacology*; D010978:Platelet Factor 4 / Q000187:drug effects* / Q000378:metabolism; D020521:Stroke / Q000378:metabolism / Q000503:physiopathology
chemical_list: C503460:Ccl5 protein, mouse; D018946:Chemokine CCL5; C000625932:MKEY peptide; D010456:Peptides, Cyclic; D010978:Platelet Factor 4
keywords: cerebrovascular disease/stroke; immunology; infarct or infarction; inflammation