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Background and Purpose: Adipocyte fatty acid‐binding protein (A‐FABP) exacerbates cerebral ischaemia injury by disrupting the blood–brain barrier (BBB) through inducing expression of MMP‐9. Circulating A‐FABP levels positively correlate with infarct size in stroke patients. We hypothesized that targeting circulating A‐FABP by a neutralizing antibody would alleviate ischaemic stroke outcome. Experimental Approach: Monoclonal antibodies (mAbs) against A‐FABP were generated using mouse hybridoma techniques. Binding affinities of a generated mAb named 6H2 towards various FABPs were determined using Biacore. Molecular docking studies were performed to characterize the 6H2‐A‐FABP complex structure and epitope. The therapeutic potential and safety of 6H2 were evaluated in mice with transient middle cerebral artery occlusion (MCAO) and healthy mice, respectively. Key Results: Replenishment of recombinant A‐FABP exaggerated the stroke outcome in A‐FABP‐deficient mice. 6H2 exhibited nanomolar to picomolar affinities to human and mouse A‐FABP, respectively, with minimal cross‐reactivities with heart and epidermal FABPs. 6H2 effectively neutralized JNK/c‐Jun activation elicited by A‐FABP and reduced MMP‐9 production in macrophages. Molecular docking suggested that 6H2 interacts with the "lid" of the fatty acid binding pocket of A‐FABP, thus likely hindering the binding of its substrates. In mice with transient MCAO, 6H2 significantly attenuated BBB disruption, cerebral oedema, infarction, neurological deficits, and decreased mortality associated with reduced cytokine and MMP‐9 production. Chronic 6H2 treatment showed no obvious adverse effects in healthy mice. Conclusion and Implications: These results establish circulating A‐FABP as a viable therapeutic target for ischaemic stroke, and provide a highly promising antibody drug candidate with high affinity and specificity. [ABSTRACT FROM AUTHOR]

Background: Reperfusion therapy after ischemic stroke often causes brain microvascular injury. However, the underlying mechanisms are unclear. Methods: Transcriptomic and proteomic analyses were performed on human cerebral microvascular endothelial cells following oxygen–glucose deprivation (OGD) or OGD plus recovery (OGD/R) to identify molecules and signaling pathways dysregulated by reperfusion. Major findings were further validated in a mouse model of cerebral ischemia and reperfusion. Results: Transcriptomic analysis identified 390 differentially expressed genes (DEGs) between the OGD/R and OGD group. Pathway analysis indicated that these genes were mostly associated with inflammation, including the TNF signaling pathway, TGF‐β signaling pathway, cytokine–cytokine receptor interaction, NOD‐like receptor signaling pathway, and NF‐κB signaling pathway. Proteomic analysis identified 201 differentially expressed proteins (DEPs), which were primarily associated with extracellular matrix destruction and remodeling, impairment of endothelial transport function, and inflammatory responses. Six genes (DUSP1, JUNB, NFKBIA, NR4A1, SERPINE1, and THBS1) were upregulated by OGD/R at both the mRNA and protein levels. In mice with cerebral ischemia and reperfusion, brain TNF signaling pathway was activated by reperfusion, and inhibiting TNF‐α with adalimumab significantly attenuated reperfusion‐induced brain endothelial inflammation. In addition, the protein level of THBS1 was substantially upregulated upon reperfusion in brain endothelial cells and the peri‐endothelial area in mice receiving cerebral ischemia. Conclusion: Our study reveals the key molecular signatures of brain endothelial reperfusion injury and provides potential therapeutic targets for the treatment of brain microvascular injury after reperfusion therapy in ischemic stroke. [ABSTRACT FROM AUTHOR]

Oligodendrocytes myelinate axons in the central nervous system and develop from oligodendrocyte precursor cells (OPCs) that must first migrate extensively during brain and spinal cord development. We show that OPCs require the vasculature as a physical substrate for migration. We observed that OPCs of the embryonic mouse brain and spinal cord, as well as the human cortex, emerge from progenitor domains and associate with the abluminal endothelial surface of nearby blood vessels. Migrating OPCs crawl along and jump between vessels. OPC migration in vivo was disrupted in mice with defective vascular architecture but was normal in mice lacking pericytes. Thus, physical interactions with the vascular endothelium are required for OPC migration. We identify Wnt-Cxcr4 (chemokine receptor 4) signaling in regulation of OPC-endothelial interactions and propose that this signaling coordinates OPC migration with differentiation.

Low-grade, chronic inflammation has been associated with many diseases of aging, but the mechanisms responsible for producing this inflammation remain unclear. Inflammasomes can drive chronic inflammation in the context of an infectious disease or cellular stress, and they trigger the maturation of interleukin-1[beta] (IL-1[beta]). Here we find that the expression of specific inflammasome gene modules stratifies older individuals into two extremes: those with constitutive expression of IL-1[beta], nucleotide metabolism dysfunction, elevated oxidative stress, high rates of hypertension and arterial stiffness; and those without constitutive expression of IL-1[beta], who lack these characteristics. Adenine and N[sup.4]-acetylcytidine, nucleotide-derived metabolites that are detectable in the blood of the former group, prime and activate the NLRC4 inflammasome, induce the production of IL-1[beta], activate platelets and neutrophils and elevate blood pressure in mice. In individuals over 85 years of age, the elevated expression of inflammasome gene modules was associated with all-cause mortality. Thus, targeting inflammasome components may ameliorate chronic inflammation and various other age-associated conditions., Author(s): David Furman (corresponding author) [1, 2]; Junlei Chang [3]; Lydia Lartigue [4]; Christopher R Bolen [5]; François Haddad [6]; Brice Gaudilliere [5]; Edward A Ganio [5]; Gabriela K Fragiadakis [...]