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This third in a series of vascular cognitive impairment (VCI) workshops, supported by "The Leo and Anne Albert Charitable Trust," was held from February 8 to 12 at the Omni Resort in Carlsbad, CA. This workshop followed the information gathered from the earlier two workshops suggesting that we focus more specifically on brain white matter in age-related cognitive impairment. The Scientific Program Committee (Frank Barone, Shawn Whitehead, Eric Smith, and Rod Corriveau) assembled translational, clinical, and basic scientists with unique expertise in acute and chronic white matter injury at the intersection of cerebrovascular and neurodegenerative etiologies. As in previous Albert Trust workshops, invited participants addressed key topics related to mechanisms of white matter injury, biomarkers of white matter injury, and interventions to prevent white matter injury and age-related cognitive decline. This report provides a synopsis of the presentations and discussions by the participants, including the existing knowledge gaps and the delineation of the next steps towards advancing our understanding of white matter injury and age-related cognitive decline. Workshop discussions and consensus resulted in action by The Albert Trust to (1) increase support from biannual to annual "White Matter and Cognition" workshops; (2) provide funding for two collaborative, novel research grants annually submitted by meeting participants; and (3) coordinate the formation of the "Albert Research Institute for White Matter and Cognition." This institute will fill a gap in white matter science, providing white matter and cognition communications, including annual updates from workshops and the literature and interconnecting with other Albert Trust scientific endeavors in cognition and dementia, and providing support for newly established collaborations between seasoned investigators and to the development of talented young investigators in the VCI-dementia (VCID) and white matter cognitio

Background－Oligodendrocyte precursor cells (OPCs) regulate neuronal, glial, and vascular systems in diverse ways and display phenotypic heterogeneity beyond their established role as a reservoir for mature oligodendrocytes. However, the detailed phenotypic changes of OPCs after cerebral ischemia remain largely unknown. Here, we aimed to investigate the roles of reactive OPCs in the ischemic brain. Methods and Results－The behavior of OPCs was evaluated in a mouse model of ischemic stroke produced by transient middle cerebral artery occlusion in vivo. For in vitro experiments, the phenotypic change of OPCs after oxygen glucose derivation was examined using a primary rat OPC culture. Furthermore, the therapeutic potential of hypoxic OPCs was evaluated in a mouse model of middle cerebral artery occlusion in vivo. Perivascular OPCs in the cerebral cortex were increased alongside poststroke angiogenesis in a mouse model of middle cerebral artery occlusion. In vitro RNA‐seq analysis revealed that primary cultured OPCs increased the gene expression of numerous pro‐angiogenic factors after oxygen glucose derivation. Hypoxic OPCs secreted a greater amount of pro‐angiogenic factors, such as vascular endothelial growth factor and angiopoietin‐1, compared with normoxic OPCs. Hypoxic OPC‐derived conditioned media increased the viability and tube formation of endothelial cells. In vivo studies also demonstrated that 5 consecutive daily treatments with hypoxic OPC‐conditioned media, beginning 2 days after middle cerebral artery occlusion, facilitated poststroke angiogenesis, alleviated infarct volume, and improved functional disabilities. Conclusions－Following cerebral ischemia, the phenotype of OPCs in the cerebral cortex shifts from the parenchymal subtype to the perivascular subtype, which can promote angiogenesis. The optimal use of hypoxic OPCs secretome would provide a novel therapeutic option for stroke.

Biomaterials provide novel platforms to deliver stem cell and growth factor therapies for central nervous system (CNS) repair. The majority of these approaches have focused on the promotion of neural progenitor cells and neurogenesis. However, it is now increasingly recognized that glial responses are critical for recovery in the entire neurovascular unit. In this study, we investigated the cellular effects of epidermal growth factor (EGF) containing hydrogels on primary astrocyte cultures. Both EGF alone and EGF‐hydrogel equally promoted astrocyte proliferation, but EGF‐hydrogels further enhanced astrocyte activation, as evidenced by a significantly elevated Glial fibrillary acidic protein (GFAP) gene expression. Thereafter, conditioned media from astrocytes activated by EGF‐hydrogel protected neurons against injury and promoted synaptic plasticity after oxygen–glucose deprivation. Taken together, these findings suggest that EGF‐hydrogels can shift astrocytes into neuro‐supportive phenotypes. Consistent with this idea, quantitative‐polymerase chain reaction (qPCR) demonstrated that EGF‐hydrogels shifted astrocytes in part by downregulating potentially negative A1‐like genes (Fbln5 and Rt1‐S3) and upregulating potentially beneficial A2‐like genes (Clcf1, Tgm1, and Ptgs2). Further studies are warranted to explore the idea of using biomaterials to modify astrocyte behavior and thus indirectly augment neuroprotection and neuroplasticity in the context of stem cell and growth factor therapies for the CNS. Stem Cells Translational Medicine 2019 Biomaterials provide novel platforms to deliver stem cell and growth factor therapies for central nervous system repair. Our data suggest that epidermal growth factor‐containing hydrogels can shift astrocytes into potentially beneficial A2‐like phenotypes that may augment neuroprotection and neuroplasticity during the recovery phase after brain injury.

Biomaterials provide novel platforms to deliver stem cell and growth factor therapies for central nervous system (CNS) repair. The majority of these approaches have focused on the promotion of neural progenitor cells and neurogenesis. However, it is now increasingly recognized that glial responses are critical for recovery in the entire neurovascular unit. In this study, we investigated the cellular effects of epidermal growth factor (EGF) containing hydrogels on primary astrocyte cultures. Both EGF alone and EGF‐hydrogel equally promoted astrocyte proliferation, but EGF‐hydrogels further enhanced astrocyte activation, as evidenced by a significantly elevated Glial fibrillary acidic protein (GFAP) gene expression. Thereafter, conditioned media from astrocytes activated by EGF‐hydrogel protected neurons against injury and promoted synaptic plasticity after oxygen–glucose deprivation. Taken together, these findings suggest that EGF‐hydrogels can shift astrocytes into neuro‐supportive phenotypes. Consistent with this idea, quantitative‐polymerase chain reaction (qPCR) demonstrated that EGF‐hydrogels shifted astrocytes in part by downregulating potentially negative A1‐like genes (Fbln5 and Rt1‐S3) and upregulating potentially beneficial A2‐like genes (Clcf1, Tgm1, and Ptgs2). Further studies are warranted to explore the idea of using biomaterials to modify astrocyte behavior and thus indirectly augment neuroprotection and neuroplasticity in the context of stem cell and growth factor therapies for the CNS. Stem Cells Translational Medicine 2019 Biomaterials provide novel platforms to deliver stem cell and growth factor therapies for central nervous system repair. Our data suggest that epidermal growth factor‐containing hydrogels can shift astrocytes into potentially beneficial A2‐like phenotypes that may augment neuroprotection and neuroplasticity during the recovery phase after brain injury.

Chronic cerebral hypoperfusion is a characteristic seen in widespread CNS diseases, including neurodegenerative and mental disorders, and is commonly accompanied by cognitive impairment. Recently, several studies demonstrated that chronic cerebral hypoperfusion can induce the excessive inflammatory responses that precede neuronal dysfunction; however, the precise mechanism of cognitive impairment due to chronic cerebral hypoperfusion remains unknown. Transient receptor potential melastatin 2 (TRPM2) is a Ca2+-permeable channel that is abundantly expressed in immune cells and is involved in aggravation of inflammatory responses. Therefore, we investigated the pathophysiological role of TRPM2 in a mouse chronic cerebral hypoperfusion model with bilateral common carotid artery stenosis (BCAS). When male mice were subjected to BCAS, cognitive dysfunction and white matter injury at day 28 were significantly improved in TRPM2-knockout (TRPM2-KO) mice compared with wild-type (WT) mice, whereas hippocampal damage was not observed. There were no differences in blood-brain barrier breakdown and H2O2 production between the two genotypes at 14 and 28 days after BCAS. Cytokine production was significantly suppressed in BCAS-operated TRPM2-KO mice compared with WT mice at day 28. In addition, the number of Iba1-positive cells gradually decreased from day 14. Moreover, daily treatment with minocycline significantly improved cognitive perturbation. Surgical techniques using bone marrow chimeric mice revealed that activated Iba1-positive cells in white matter could be brain-resident microglia, not peripheral macrophages. Together, these findings suggest that microglia contribute to the aggravation of cognitive impairment by chronic cerebral hypoperfusion, and that TRPM2 may be a potential target for chronic cerebral hypoperfusion-related disorders.

As the human population continues to age, an increasing number of people will exhibit significant deficits in cognitive function and dementia. It is now recognized that cerebrovascular, metabolic and neurodegenerative diseases all play major roles in the evolution of cognitive impairment and dementia. Thus with our more recent recognition of these relationships and our need to understand and more positively impact on this world health problem, "The Leo and Anne Albert Charitable Trust" (Gene Pranzo, Trustee with significant support from Susan Brogan, Meeting Planner) provided generous support for this inaugural international workshop that was held from April 13-16, 2015 at the beautiful Ritz Carlton Golf Resort in North Naples, Florida. Researchers from SUNY Downstate Medical Center, Brooklyn, NY organized the event by selecting the present group of translationally inclined preclinical, clinical and population scientists focused on cerebrovascular disease (CVD) risk and its progression to vascular cognitive impairment (VCI) and dementia. Participants at the workshop addressed important issues related to aging, cognition and dementia by: (1) sharing new data, information and perspectives that intersect vascular, metabolic and neurodegenerative diseases, (2) discussing gaps in translating population risk, clinical and preclinical information to the progression of cognitive loss, and (3) debating new approaches and methods to fill these gaps that can translate into future therapeutic interventions. Participants agreed on topics for group discussion prior to the meeting and focused on specific translational goals that included promoting better understanding of dementia mechanisms, the identification of potential therapeutic targets for intervention, and discussed/debated the potential utility of diagnostic/prognostic markers. Below summarizes the new data-presentations, concepts, novel directions and specific discussion topics addressed by this international translation

Tissue plasminogen activator (tPA) is the only FDA-approved treatment for reperfusing ischemic strokes. But widespread use of tPA is still limited by fears of inadvertently administering tPA in patients with intracerebral hemorrhage (ICH). Surprisingly, however, the assumption that tPA will worsen ICH has never been biologically tested. Here, we assessed the effects of tPA in two models of ICH. In a mouse model of collagenase-induced ICH, hemorrhage volumes and neurological deficits after 24 hrs were similar in saline controls and tPA-treated mice, whereas heparin-treated mice had 3-fold larger hematomas. In a model of laser-induced vessel rupture, tPA also did not worsen hemorrhage volumes, while heparin did. tPA is known to worsen neurovascular injury by amplifying matrix metalloproteinases during cerebral ischemia. In contrast, tPA did not upregulate matrix metalloproteinases in our mouse ICH models. In summary, our experimental data do not support the assumption that intravenous tPA has a deleterious effect in acute ICH. However, due to potential species differences and the inability of models to fully capture the dynamics of human ICH, caution is warranted when considering the implications of these findings for human therapy.

Measurements of oxygen partial pressure (pO(2)) with high temporal and spatial resolution in three dimensions is crucial for understanding oxygen delivery and consumption in normal and diseased brain. Among existing pO(2) measurement methods, phosphorescence quenching is optimally suited for the task. However, previous attempts to couple phosphorescence with two-photon laser scanning microscopy have faced substantial difficulties because of extremely low two-photon absorption cross-sections of conventional phosphorescent probes. Here we report to our knowledge the first practical in vivo two-photon high-resolution pO(2) measurements in small rodents' cortical microvasculature and tissue, made possible by combining an optimized imaging system with a two-photon-enhanced phosphorescent nanoprobe. The method features a measurement depth of up to 250 microm, sub-second temporal resolution and requires low probe concentration. The properties of the probe allowed for direct high-resolution measurement of cortical extravascular (tissue) pO(2), opening many possibilities for functional metabolic brain studies.

Measurements of oxygen partial pressure (pO(2)) with high temporal and spatial resolution in three dimensions is crucial for understanding oxygen delivery and consumption in normal and diseased brain. Among existing pO(2) measurement methods, phosphorescence quenching is optimally suited for the task. However, previous attempts to couple phosphorescence with two-photon laser scanning microscopy have faced substantial difficulties because of extremely low two-photon absorption cross-sections of conventional phosphorescent probes. Here we report to our knowledge the first practical in vivo two-photon high-resolution pO(2) measurements in small rodents' cortical microvasculature and tissue, made possible by combining an optimized imaging system with a two-photon-enhanced phosphorescent nanoprobe. The method features a measurement depth of up to 250 microm, sub-second temporal resolution and requires low probe concentration. The properties of the probe allowed for direct high-resolution measurement of cortical extravascular (tissue) pO(2), opening many possibilities for functional metabolic brain studies.

The Ca2+ signal facilitates nuclear translocation of NFAT through the dephosphorylation of clustered serine residues in the calcium regulatory domain by the Ca2+/calmodulin-dependent phosphatase calcineurin. The conformation of dephosphorylated NFAT exposes the nuclear localization signal for translocation into the nucleus and masks the nuclear export sequence to keep the protein in the nucleus. It has been reported that deletion of some serine-rich motifs masking the nuclear localization signal results in the translocation of NFAT into the nucleus, but that the nuclear export sequence located at the N terminus also needs to be deleted for NFATx (NFAT4/NFATc3) to exert efficient transactivation function. Here, we report that deletion of the critical serine-rich motifs of NFATx leads to a conformation that efficiently exposes the nuclear localization signal and that has stronger transcription activity compared with the fully activated wild-type protein in the presence of the nuclear export sequence. This also suggests that the regulation of the transactivation domain by phosphorylation observed in NFAT1 may not contribute significantly to the transcription activity of NFATx. The expression of this constitutively nuclear form of NFATx in the CD4+CD8+ T cell line facilitates differentiation into the CD4 single-positive stage upon stimulation with phorbol ester. Our data suggest that NFATx is involved in the regulation of co-receptor expression during differentiation into the CD4 single-positive stage.

The Ca2+ signal facilitates nuclear translocation of NFAT through the dephosphorylation of clustered serine residues in the calcium regulatory domain by the Ca2+/calmodulin-dependent phosphatase calcineurin. The conformation of dephosphorylated NFAT exposes the nuclear localization signal for translocation into the nucleus and masks the nuclear export sequence to keep the protein in the nucleus. It has been reported that deletion of some serine-rich motifs masking the nuclear localization signal results in the translocation of NFAT into the nucleus, but that the nuclear export sequence located at the N terminus also needs to be deleted for NFATx (NFAT4/NFATc3) to exert efficient transactivation function. Here, we report that deletion of the critical serine-rich motifs of NFATx leads to a conformation that efficiently exposes the nuclear localization signal and that has stronger transcription activity compared with the fully activated wild-type protein in the presence of the nuclear export sequence. This also suggests that the regulation of the transactivation domain by phosphorylation observed in NFAT1 may not contribute significantly to the transcription activity of NFATx. The expression of this constitutively nuclear form of NFATx in the CD4+CD8+ T cell line facilitates differentiation into the CD4 single-positive stage upon stimulation with phorbol ester. Our data suggest that NFATx is involved in the regulation of co-receptor expression during differentiation into the CD4 single-positive stage.

現在まで種々の有機硫黄試薬が開発され,報告されている｡特に共役付加反応を行う硫黄試 薬は,新たな不斉点を同時に2つの炭素に創出するため,活発な報告がなされている｡ 一方,アンジオテンシン変換酵素(ACE)阻害剤は,カプトプリルに代表されるように,疏 黄を含む種々の化合物が報告されており,抗高血圧剤として広く用いられ,注目を集めている｡ 今回我々は,選択的に共役付加反応だけを行う有機硫黄試薬と,反応によって生成する有機 硫黄化合物の構造と生理活性の相関に興味を持ち,硫黄を含む新たな有機銅試薬を開発し,良 好な結果を得たので報告する｡

The predominant action of cilostazol on Aβ metabolism is likely to facilitate Aβ clearance due to the sustained cerebrovascular function in vivo. Our findings mechanistically demonstrate that cilostazol is a promising therapeutic approach for AD and CAA.