title: The CCL2-CCR2 system affects the progression and clearance of intracerebral hemorrhage.
abstract: Intracerebral hemorrhage (ICH) has been associated with inflammation and apoptosis. The CCL2-CCR2 chemotactic system is one of the major signaling pathways that induce inflammation and apoptosis. However, its role on ICH has not been investigated. We subjected wild-type, CCL2(-/-) , and CCR2(-/-) mice to collagenase-induced ICH, and assessed histological and behavioral outcomes. Lack of CCL2 or CCR2 decreased the hematoma volume early after collagenase-induced ICH but delayed its recovery. The hematoma size was accompanied by brain edema, neuronal death, and neurological scores. Although microglia activation/migration was attenuated in CCL2(-/-) or CCR2(-/-) mice 1 day after injury, more microglia were present at later time points, suggesting that alternative signaling pathways had been activated to recruit them. On the contrary, leukocyte and neutrophil infiltration were decreased in these mice, suggesting a tighter/recovered blood-brain barrier. In addition, we also found that FL- and K104Stop-CCL2 were able to restore the changes found in CCL2(-/-) mice, but K104A-CCL2 failed to do so. These results suggest that plasmin-mediated truncation of CCL2 may be an indispensable step to fully activate the chemokine in vivo. The data also indicate that CCL2-CCR2 signaling pathway may be a molecular target for the treatment of ICH.
authors.affiliation: Department of Pharmacological Sciences, Program in Molecular and Cellular Pharmacology, Stony Brook University, Stony Brook, NY, USA.
authors.forename: Yao
authors.initials: Y
authors.lastname: Yao
authors.forename: Stella E
authors.initials: SE
authors.lastname: Tsirka
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000950:Antigens, Ly / Q000378:metabolism; D001929:Brain Edema / Q000188:drug therapy / Q000209:etiology / Q000473:pathology; D002135:Calcium-Binding Proteins / Q000378:metabolism; D002543:Cerebral Hemorrhage / Q000139:chemically induced / Q000150:complications / Q000378:metabolism* / Q000628:therapy*; D018932:Chemokine CCL2 / Q000172:deficiency / Q000378:metabolism*; D002634:Chemotaxis, Leukocyte / Q000276:immunology; D017364:Collagenases / Q000009:adverse effects; D004195:Disease Models, Animal; D018450:Disease Progression; D005452:Fluoresceins; D007839:Functional Laterality; D005786:Gene Expression Regulation / Q000235:genetics; D017493:Leukocyte Common Antigens / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008840:Microfilament Proteins / Q000378:metabolism; D017628:Microglia / Q000378:metabolism; D009422:Nervous System Diseases / Q000209:etiology / Q000235:genetics; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D009930:Organic Chemicals; D054390:Receptors, CCR2 / Q000172:deficiency / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D013997:Time Factors
chemical_list: C491049:Aif1 protein, mouse; D000950:Antigens, Ly; D002135:Calcium-Binding Proteins; C491768:Ccl2 protein, mouse; C515335:Ccr2 protein, mouse; D018932:Chemokine CCL2; D005452:Fluoresceins; C480309:Ly6G antigen, mouse; D008840:Microfilament Proteins; D009930:Organic Chemicals; D054390:Receptors, CCR2; C435731:fluoro jade; D052247:Nitric Oxide Synthase Type II; D017493:Leukocyte Common Antigens; D017364:Collagenases