Faculty Profiles - SUZUKI, Hiromi

Signal Sequence-Dependent Orientation of Signal Peptide Fragments to Exosomes. Reviewed

Ono K, Niwa M, Suzuki H, Kobayashi NB, Yoshida T, Sawada M

International Journal of Molecular Sciences Vol. 23 ( 6 ) page： 3137 2022.3

Language：English Publishing type：Research paper (scientific journal)

Signal peptides (SPs) not only mediate targeting to the endoplasmic reticulum (ER) but also play important roles as biomarkers and substances with physiological activity in extracellular fluids including blood. SPs are thought to be degraded intracellularly, making it unclear how they are transported from the ER to the extracellular fluid. In a recent study, we showed that a C-terminal fragment of the SP of a type I membrane protein, amyloid precursor protein (APP), was secreted into the extracellular fluid via exosomes using transformed HEK293 cells expressing APP SP flanking a reporter protein. In the present study, we demonstrate that a N-terminal fragment of the SP from a type II membrane protein, human placental secreted alkaline phosphatase (SEAP), is contained in exosomes and secreted into the extracellular fluid using HEK-Blue hTLR3 cells, which express both a human toll-like receptor 3 gene and an inducible SEAP reporter gene. When HEK-Blue hTLR3 cells were stimulated with a TLR3 ligand, a N-terminal fragment of SEAP SP in exosomes was increased in parallel with SEAP secretion in a concentration-dependent manner. These results indicated that SP fragments are exosomal components. In addition, migrating SP fragments were determined by characteristics of the signal–anchor sequence of membrane proteins. Furthermore, we found that SP fragments could bind to calmodulin (CALM), which is a cytosolic protein and also a component of exosomes, suggesting its involvement in the transportation of SP fragments from the endoplasmic reticulum to exosomes.

DOI： 10.3390/ijms23063137

Other Link： https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8950404/

Secretion of signal peptides via extracellular vesicles Reviewed International journal

Ono K, Niwa M, Suzuki H, Kobayashi NB, Yoshida T, Sawada M.

Biochem Biophys Res Commun . Vol. 560 page： 21 - 26 2021.5

Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier

Signal peptides (SPs) consist of short peptide sequences present at the N-terminal of newly synthesizing proteins and act as a zip code for the translocation of the proteins to the endoplasmic reticulum (ER). It was thought that the SPs are intracellularly degraded after translocation to the ER; however, recent studies showed cleaved SPs have diverse roles for controlling cell functions in auto- and/or intercellular manners. In addition, it still remains obscure how SP fragments translocate away from the site where they are produced. Extracellular vesicles (EV) are important for intercellular communication and can transport functional molecules to specific cells. In this study, we show that SPs are involved in EV from T-REx AspALP cells that were transfected with a human APP SP-inducible expression vector. There was no difference in the average particle size or particle concentration of EV collected from T-REx AspALP cells and T-REx Mock cells. When the SP content in the EV was examined by mass spectrometry, the C-terminal fragment of APP SP was identified in the exosomes (SEV) of T-REx AspALP cells. In our preparation of SEV fractions, no ER-specific proteins were detected; therefore, SPs may be included in SEV but not in the debris of degraded ER. This is the first indication that SPs are secreted from cells via EV.

DOI： 10.1016/j.bbrc.2021.04.073.

Peripheral benzodiazepine receptor/18 kDa translocator protein positron emission tomography imaging in a rat model of acute brain injury Reviewed International coauthorship

Nomura M, Toyama H, Suzuki H, Yamada T, Hatano K, Alan A Wilson, Ito K, Sawada M

Ann Null Med. Vol. 35 ( 1 ) page： 8 - 16 2021.1

Distribution of Signal Peptides in Microvesicles from Activated Macrophage Cells Invited Reviewed

International Journal of Molecular Science Vol. 24 ( 15 ) 2023.7

Calmodulin as a Key Regulator of Exosomal Signal Peptides. Invited Reviewed International journal

Kenji Ono, Mikio Niwa, Hiromi Suzuki, Nahoko Bailey Kobayashi, Tetsuhiko Yoshida, Makoto Sawada

Cells Vol. 12 ( 1 ) page： 158 2022.12

Language：English Publishing type：Research paper (scientific journal)

Signal peptides (SPs) and their fragments play important roles as biomarkers and substances with physiological functions in extracellular fluid. We previously reported that SP fragments were released into extracellular fluid via exosomes and bound to calmodulin (CaM), an exosomal component, in a cell-free system. However, it currently remains unclear whether CaM intracellularly interacts with SP fragments or is involved in the trafficking of these fragments to exosomes. Therefore, the present study examined the binding of CaM to SP fragments in T-REx AspALP cells, transformed HEK293 cells expressing amyloid precursor protein (APP) SP flanking a reporter protein, and their exosomes. APP SP fragments were detected in exosomes from T-REx AspALP cells in the absence of W13, a CaM inhibitor, but were present in lower amounts in exosomes from W13-treated cells. Cargo proteins, such as Alix, CD63, and CD81, were increased in W13-treated T-REx AspALP cells but were decreased in their exosomes. Furthermore, CaM interacted with heat shock protein 70 and CD81 in T-REx AspALP cells and this increased in the presence of W13. APP SP fragments were detected in intracellular CaM complexes in the absence of W13, but not in its presence. These results indicate that CaM functions as a key regulator of the transport of SP fragments into exosomes and plays novel roles in the sorting of contents during exosomal biogenesis.

DOI： 10.3390/cells12010158

Inhibition of cellular inflammatory mediator production and amelioration of learning deficit in flies by deep sea Aspergillus-derived cyclopenin. Reviewed International coauthorship

Wang L, Li M, Lin Y, Du S, Liu Z, Ju J, Suzuki H, Sawada M, Umezawa K

The Journal of antibiotics Vol. 73 ( 9 ) page： 622 - 629 2020.9

Language：English Publishing type：Research paper (scientific journal)

In the course of screening lipopolysaccharide (LPS)-induced nitric oxide (NO) production inhibitors, two related benzodiazepine derivatives, cyclopenol and cyclopenin, were isolated from the extract of a deep marine-derived fungal strain, Aspergillus sp. SCSIOW2. Cyclopenol and cyclopenin inhibited the LPS-induced formation of NO and secretion of IL-6 in RAW264.7 cells at nontoxic concentrations. In terms of the mechanism underlying these effects, cyclopenol and cyclopenin were found to inhibit the upstream signal of NF-κB activation. These compounds also inhibited the expression of IL-1β, IL-6, and inducible nitric oxide synthase (iNOS) in mouse microglia cells, macrophages in the brain. In relation to the cause of Alzheimer’s disease, amyloid-β-peptide is known to induce inflammation in the brain. Therefore, the present study investigated the ameliorative effects of these inhibitors on an in vivo Alzheimer’s model using flies. Learning deficits were induced by the overexpression of amyloid-β42 in flies, and cyclopenin but not cyclopenol was found to rescue learning impairment. Therefore, novel anti-inflammatory activities of cyclopenin were identified, which may be useful as a candidate of anti-inflammatory agents for neurodegenerative diseases.

DOI： 10.1038/s41429-020-0302-9

Dipeptidyl peptidase-4 inhibition prevents nonalcoholic steatohepatitis-associated liver fibrosis and tumor development in mice independently of its anti-diabetic effects Reviewed International coauthorship

Mitsuhiro Kawakubo, Miyako Tanaka, Kozue Ochi, Akiko Watanabe, Marie Saka-Tanaka, Yohei Kanamori, Naoki Yoshioka, Satoko Yamashita, Moritaka Goto, Michiko Itoh, Ibuki Shirakawa, Sayaka Kanai, Hiromi Suzuki, Makoto Sawada, Ayaka Ito, Masatoshi Ishigami, Mitsuhiro Fujishiro, Hiroshi Arima, Yoshihiro Ogawa, Takayoshi Suganami

Science Report Vol. 10 ( 1 ) page： 983 2020.1

Language：English Publishing type：Research paper (scientific journal)

Nonalcoholic steatohepatitis (NASH) is a hepatic phenotype of the metabolic syndrome, and increases the risk of cirrhosis and hepatocellular carcinoma (HCC). Although increasing evidence points to the therapeutic implications of certain types of anti-diabetic agents in NASH, it remains to be elucidated whether their effects on NASH are independent of their effects on diabetes. Genetically obese melanocortin 4 receptor-deficient (MC4R-KO) mice fed Western diet are a murine model that sequentially develops hepatic steatosis, NASH, and HCC in the presence of obesity and insulin resistance. In this study, we investigated the effect of the dipeptidyl peptidase-4 (DPP-4) inhibitor anagliptin on NASH and HCC development in MC4R-KO mice. Anagliptin treatment effectively prevented inflammation, fibrosis, and carcinogenesis in the liver of MC4R-KO mice. Interestingly, anagliptin only marginally affected body weight, systemic glucose and lipid metabolism, and hepatic steatosis. Histological data and gene expression analysis suggest that anagliptin treatment targets macrophage activation in the liver during the progression from simple steatosis to NASH. As a molecular mechanism underlying anagliptin action, we showed that glucagon-like peptide-1 suppressed proinflammatory and profibrotic phenotypes of macrophages in vitro. This study highlights the glucose metabolism-independent effects of anagliptin on NASH and HCC development.

DOI： 10.1038/s41598-020-57935-6

Novel Oxindole-Curcumin Hybrid Compound for Antioxidative Stress and Neuroprotection Reviewed

Yoko Hirata, Yuki Ito, Madoka Takashima, Kazuya Yagyu, Kentaro Oh-Hashi, Hiromi Suzuki, Kenji Ono, Kyoji Furuta, Makoto Sawada

ACS Chem Neurosci . Vol. 11 ( 1 ) page： 76-85 2020.1

Language：English Publishing type：Research paper (scientific journal)

Oxidative stress plays an important role in the pathogenesis of Parkinson's disease and other neurodegenerative disorders. The oxindole compound GIF-2165X-G1 is a hybrid molecule composed of the oxindole skeleton of the neuroprotective compound GIF-0726-r and the polyphenolic skeleton of the antioxidant curcumin. We previously reported that novel oxindole derivatives such as GIF-0726-r and GIF-2165X-G1 prevent endogenous oxidative stress-induced cell death in mouse hippocampal HT22 cells. In this study, we present a detailed investigation of the effect of GIF-2165X-G1 on endogenous oxidative stress in HT22 cells in comparison with GIF-0726-r and curcumin. GIF-2165X-G1 exhibited more potent neuroprotective activity than GIF-0726-r or curcumin and had less cytotoxicity than that observed with curcumin. Both GIF-0726-r and GIF-2165X-G1 were found to have ferrous ion chelating activity similar to that exhibited by curcumin. GIF-2165 X-G1 and curcumin induced comparable antioxidant response element transcriptional activity. Although the induction of heme oxygenase-1, an antioxidant response element-regulated gene product, was much stronger in curcumin-treated cells than in GIF-2165X-G1-treated cells, it turned out that the induction of heme oxygenase-1 is dispensable for neuroprotection. These results demonstrate that the introduction of the polyphenol skeleton of curcumin to the oxindole GIF-0726-r improves neuroprotective features. Furthermore, intrastriatal injection of GIF-2165X-G1 alleviated apomorphine-induced rotation and prevented dopaminergic neuronal loss in a 6-hydroxydopamine mouse model of Parkinson's diseases. Collectively, our novel findings indicate that the novel oxindole compound GIF-2165X-G1 serves to delay the progression of Parkinson's disease by suppressing oxidative stress.

DOI： 10.1021/acschemneuro.9b00619.

Novel oxindole derivatives prevent oxidative stress-induced cell death in mouse hippocampal HT22 cells. Reviewed

Hirata Y, Yamada C, Ito Y, Yamamoto S, Nagase H, Oh-Hashi K, Kiuchi K, Suzuki H, Sawada M, Furuta K

Neuropharmacology Vol. 135 page： 242-252 2018.3

Language：English Publishing type：Research paper (scientific journal) Publisher：Science Direct

The current medical and surgical therapies for neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease offer symptomatic relief but do not provide a cure. Thus, small synthetic compounds that protect neuronal cells from degeneration are critically needed to prevent and treat these. Oxidative stress has been implicated in various pathophysiological conditions, including neurodegenerative diseases. In a search for neuroprotective agents against oxidative stress using the murine hippocampal HT22 cell line, we found a novel oxindole compound, GIF-0726-r, which prevented oxidative stress-induced cell death, including glutamate-induced oxytosis and erastin-induced ferroptosis. This compound also exerted a protective effect on tunicamycin-induced ER stress to a lesser extent but had no effect on campthothecin-, etoposide- or staurosporine-induced apoptosis. In addition, GIF-0726-r was also found to be effective after the occurrence of oxidative stress. GIF-0726-r was capable of inhibiting reactive oxygen species accumulation and Ca2+ influx, a presumed executor in cell death, and was capable of activating the antioxidant response element, which is a cis-acting regulatory element in promoter regions of several genes encoding phase II detoxification enzymes and antioxidant proteins. These results suggest that GIF-0726-r is a low-molecular-weight compound that prevents neuronal cell death through attenuation of oxidative stress. Among the more than 200 derivatives of the GIF-0726-r synthesized, we identified the 11 most potent activators of the antioxidant response element and characterized their neuroprotective activity in HT22 cells.

DOI： 10.1016/j.neuropharm.2018.03.015

Inducible nitric oxide synthase during the late phase of sepsis is associated with hypothermia and immune cell migration. Reviewed

Takatani Y, Ono K, Suzuki H, Inaba M, Sawada M, Matsuda N

Laboratory investigation Vol. 98 ( 5 ) page： 629 - 639 2018.2

Language：English Publishing type：Research paper (scientific journal)

Hypothermia is a significant sign of sepsis, which is associated with poor prognosis, but few mechanisms underlying the regulation of hypothermia are known. Inducible nitric oxide synthase (iNOS) is a key inflammatory mediator of sepsis. However, the therapeutic benefit of iNOS inhibition in sepsis is still controversial, and requires elucidation in an accurate model system. In this study, wild-type (WT) mice showed temperature drops in a biphasic manner at the early and late phase of sepsis, and all mice died within 48 h of sepsis. In contrast, iNOS-knockout (KO) mice never showed the second temperature drop and exhibited improved mortality. Plasma nitric oxide (NO) levels of WT mice increased in the late phase of sepsis and correlated to hypothermia. The results indicate that iNOS-derived NO during the late phase of sepsis caused vasodilation-induced hypothermia and a lethal hypodynamic state. The expression of the iNOS mRNA was high in the lung of WT mice with sepsis, which reflects the pathology of acute respiratory distress syndrome (ARDS). We obtained the results in a modified keyhole-type cecal ligation and puncture model of septic shock induced by minimally invasive surgery. In this accurate and reproducible model system, we transplanted the bone marrow cells of GFP transgenic mice into WT and iNOS-KO mice, and evaluated the role of increased pulmonary iNOS expression in cell migration during the late phase of sepsis. We also investigated the quantity and type of bone marrow-derived cells (BMDCs) in the lung. The number of BMDCs in the lung of iNOS-KO mice was less than that in the lung of WT mice. The major BMDCs populations were CD11b-positive, iNOS-negative cells in WT mice, and Gr-1-positive cells in iNOS-KO mice that expressed iNOS. These results suggest that sustained hypothermia may be a beneficial guide for future iNOS-targeted therapy of sepsis, and that iNOS modulated the migratory efficiency and cell type of BMDCs in septic ARDS.

DOI： 10.1038/s41374-018-0021-z

Visualization of Arc promoter-driven neuronal activity by magnetic resonance imaging Reviewed

Qi Wu, Kenji Ono, Hiromi Suzuki, Megumi Eguchi, Shun Yamaguchi, Makoto Sawada

Neuroscience Letters Vol. 666 page： 92 - 97 2018.2

Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier Ireland Ltd

Visualization of direct neuronal activity to understand brain function is one of the most important challenges in neuroscience. We have previously demonstrated that in vivo and in vitro gene expression of the ferritin reporter system could be detected by magnetic resonance imaging (MRI). In addition, increased neuronal activity induces Arc, an immediate early gene, and insertion of a destabilized fluorescent reporter dVenus under Arc promoter control has been used for monitoring neuronal activities in the brain by optical imaging. In this study, to visualize Arc promoter-driven neuronal activities directly, we generated transgenic mice and cell lines that express a destabilized fusion reporter ferritin-mKate2 under Arc promoter control. When transgenic mice and cell lines were treated with pilocarpine, a non-selective muscarinic agonist, an increase in T2-weighted image signal was successfully found in neuronal cells. There was a difference in peak time between MRI and fluorescence imaging, which might result from the binding process of iron with ferritin. Visualization of Arc promoter-driven neuronal activity is essential to understand neural mechanisms underlying cognitive processes and complex behaviors, and could be a useful tool for therapeutic approaches in the brain by MRI.

DOI： 10.1016/j.neulet.2017.12.041

Optogenetic control of cell differentiation in channelrhodopsin-2-expressing OS3, a bipotential glial progenitor cell line

Ono K, Suzuki H, Yamamoto R, Sahashi H, Takido Y, Sawada M.

Neurochemistry International Vol. 104 page： 49-63 2017.3

Radiosynthesis and in vivo evaluation of two imidazopyridineacetamides, [11C]CB184 and [ 11C]CB190, as a PET tracer for 18 kDa translocator protein: direct comparison with [ 11C](R)-PK11195. Invited Reviewed

Hatano K, Sekimata K, Yamada T, Abe J, Ito K, Ogawa M, Magata Y, Toyohara J, Ishiwata K, Biggio G, Serra M, Laquintana V, Denora N, Latrofa A, Trapani G, Liso G, Suzuki H, Sawada M, Nomura M, Toyama H.

Annals of nuclear medicine Vol. 29 ( 4 ) page： 325 - 35 2015.5

Protective effect of INI-0602, a gap junction inhibitor, on dopaminergic neurodegeneration of mice with unilateral 6-hydroxydopamine injection

SUZUKI Hiromi,ONO Kenji,SAWADA Makoto

Journal of Neural Transmission Vol. 121 ( 11 ) page： 1349-1355 2014.11

Glutamate release from astrocyte cell-line GL261 via alterations in the intracellular ion environment Reviewed

Kenji Ono, Hiromi Suzuki, Madoka Higa, Kaori Tabata, Makoto Sawada

JOURNAL OF NEURAL TRANSMISSION Vol. 121 ( 3 ) page： 245 - 257 2014.3

Language：English Publishing type：Research paper (scientific journal) Publisher：SPRINGER WIEN

Astrocytes modify and maintain neural activity and functions via gliotransmitter release such as, glutamate. They also change their properties and functions in response to alterations of ion environment resulting from neurotransmission; however, the direct evidence for whether intracellular ion alteration in astrocytes triggers gliotransmitter release is not indicated. Recent studies have reported that channelrhodopsin-2 (ChR2) is useful for alteration of intracellular ion environment in several types of cells with blue light exposure. Here, we show that ChR2-expressing GL261 (GLChR2) cells, clonal astrocytes, change their properties by photo-activation. Increased intracellular sodium and calcium ion concentrations and an altered membrane potential were observed in GLChR2 cells with blue light exposure. Alterations in the intracellular ion environment caused intracellular acidification and the inhibition of proliferation. In addition, it triggered glutamate release from GLChR2 cells. Glutamate from GLChR2 cells acted on N18 cells, clonal neuronal cells, as both a transmitter and neurotoxin depending on photo-activation. Our results show that the properties of ChR2-expressing astrocytes can be controlled by blue light exposure, and cation influx through photo-activated ChR2 might trigger functional cation influx via endogenous channels and result in the increase of glutamate release. Further, our results suggest that ChR2-expressing glial cells could become a useful tool in understanding the roles of glial cell activation and neural communication in the regulation of brain functions.

DOI： 10.1007/s00702-013-1096-8

New Fluorescent Probes Targeting the Mitochondrial-Located Translocator Protein 18 kDa (TSPO) as Activated Microglia Imaging Agents Reviewed

Detection of cytotoxic activation of microglia in a rat neuroinflammation model using a novel translocator protein ligand, [18F]FEPPA Invited Reviewed

Nomura, M; Toyama, H; Suzuki, H; Yamada, T; Ota, S; Ichise, M; Wilson, A; Sawada, M; Ito, K; Hatano, K

JOURNAL OF NUCLEAR MEDICINE Vol. 53 2012.5

Detection of cytotoxic activation of microglia in a rat neuroinflammation model using a novel translocator protein ligand, [18F]FEPPA Reviewed

Nomura,M, Toyama,H, Suzuki,H, Yamada,T, Ota,S, Ichise,M, Wilson,AA, Sawada,M, Ito,K, Hatano,K

J Nucl Med Vol. 53(Supplement 1) page： 1884 2012

New fluorescent probes targeting the mitochondrial-located translocator protein 18 kDa (TSPO) as activated microglia imaging agents. Reviewed

DENORA N, LAQUINTANA V, TRAPANI A, SUZUKI H, SAWADA M, TRAPANI G

Pharmaceutical Research Vol. 28 ( 11 ) page： 2820-2832 2011.11

Nunzio Denora, Valentino Laquintana, Adriana Trapani, Hiromi Suzuki, Makoto Sawada, Giuseppe Trapani

PHARMACEUTICAL RESEARCH Vol. 28 ( 11 ) page： 2820 - 2832 2011.11

Language：English Publishing type：Research paper (scientific journal) Publisher：SPRINGER/PLENUM PUBLISHERS

To evaluate the utility of new Translocator protein 18 kDa (TSPO)-targeted fluorescent probes for in vivo molecular imaging of activated microglia.
Compounds 2-4 were synthesized; their stability and affinity for TSPO were determined. Compounds 2-4 were incubated both with Ra2 cells in the presence of LPS, a potent activator of microglia, and with tissue sections of normal and chemically injured brains. Compounds 2-4 were injected into carotid artery or directly in striatum of mice. Cells and tissue sections from these in vitro and in vivo studies were observed by fluorescence microscopy after histochemical treatments.
Compounds 2-4 are stable in both buffer and physiological medium and showed high affinity for TSPO and were found to stain live Ra2 microglial cells effectively. Double staining with Mito Tracker Red suggested that binding sites of compounds 2 and 3 may exist on mitochondria. In vivo studies showed that compounds 2-4 may penetrate in part into brain; moreover, cells in mouse striatum were stained with compounds 2-4 and microglial marker CD11b.
Compounds 2-4 can fluorescently label activated microglia in vitro and in vivo.

DOI： 10.1007/s11095-011-0552-0

Time-Dependent Changes in Proinflammatory and Neurotrophic Responses of Microglia and Astrocytes in a Rat Model of Osmotic Demyelination Syndrome Reviewed

Time-dependent changes in proinflammatory and neurotrophic responses of microglia and astrocytes in a rat model of osmotic demyelination syndrome. Reviewed

IWAMA S, SUGIMURA Y, SUZUKI H, SUZUKI H, MURASE T, OZAKI N, NAGASAKI H, ARIMA H, MURATA Y, SAWADA M, OISO Y

Glia Vol. 59 ( 3 ) page： 452-462 2011.3

Shintaro Iwama, Yoshihisa Sugimura, Haruyuki Suzuki, Hiromi Suzuki, Takashi Murase, Nobuaki Ozaki, Hiroshi Nagasaki, Hiroshi Arima, Yoshiharu Murata, Makoto Sawada, Yutaka Oiso

GLIA Vol. 59 ( 3 ) page： 452 - 462 2011.3

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY-LISS

Osmotic demyelination syndrome (ODS) is a serious demyelinating disease in the central nervous system usually caused by rapid correction of hyponatremia. In an animal model of ODS, we previously reported microglial accumulation expressing proinflammatory cytokines. Microglia and astrocytes secreting proinflammatory cytokines and neurotrophic factors are reported to be involved in the pathogenesis of demyelinative diseases. Therefore, to clarify the role of microglial and astrocytic function in ODS, we examined the time-dependent changes in distribution, morphology, proliferation, and mRNA/protein expression of proinflammatory cytokines, neurotrophic factors, and matrix metalloproteinase (MMP) in microglia and astrocytes 2 days (early phase) and 5 days (late phase) after the rapid correction of hyponatremia in ODS rats. The number of microglia time dependently increased at demyelinative lesion sites, proliferated, and expressed tumor necrosis factor (TNF)-alpha, interleukin (IL)-1 beta, IL-6, inducible nitric oxide synthase, and MMP2, 9, and 12 at the early phase. Microglia also expressed leukemia inhibitory factor (a neurotrophic factor) and phagocytosed myelin debris at the late phase. The number of astrocytes time dependently increased around demyelinative lesions, extended processes to lesions, proliferated, and expressed nerve growth factor and glial cell line-derived neurotrophic factor at the late phase. Moreover, treatment with infliximab, a monoclonal antibody against TNF-alpha, significantly attenuated neurological impairments. Our results suggest that the role of microglia in ODS is time dependently shifted from detrimental to protective and that astrocytes play a protective role at the late phase. Modulation of excessive proinflammatory responses in microglia during the early phase after rapid correction may represent a therapeutic target for ODS. (C)2010 Wiley-Liss. Inc.

DOI： 10.1002/glia.21114

Electrosprayed Synthesis of Red-Blood-Cell-Like Particles with Dual Modality for Magnetic Resonance and Fluorescence Imaging Reviewed

Pathway analysis of single-microglia gene-expression profiles reveals the new molecular targets of minocycline treatment Invited Reviewed

Suzuki Haruyuki, Sugimura Yoshihisa, Iwama Shintaro, Suzuki Hiromi, Takagi Hiroshi, Kiyota Atsushi, Fukuoka Kazuki, Sawada Makoto, Oiso Yutaka

NEUROSCIENCE RESEARCH Vol. 71 page： E223 - E223 2011

Brain-Targeting DDS with Microglia without Destruction of Blood-Brain Barrier Invited Reviewed

Sawada Makoto, Suzuki Hiromi, Ono Kenji

Journal of Pharmaceutical Science and Technology, Japan Vol. 71 ( 5 ) page： 259 - 267 2011

Visualization of iNOS gene expression from activated cells in magnetic resonance imaging Invited Reviewed International journal

Kenji Ono, Kaori Tabata, Hiromi Suzuki, Makoto Sawada

NEUROSCIENCE RESEARCH Vol. 71 page： E96 - E96 2011

Minocycline Prevents Osmotic Demyelination Syndrome by Inhibiting the Activation of Microglia Invited Reviewed

Suzuki Haruyuki, Sugimura Yoshihisa, Iwama Shintaro, Suzuki Hiromi, Nobuaki Ozaki, Nagasaki Hiroshi, Arima Hiroshi, Sawada Makoto, Oiso Yutaka

JOURNAL OF THE AMERICAN SOCIETY OF NEPHROLOGY Vol. 21 ( 12 ) page： 2090 - 2098 2010.12

Koichiro Hayashi, Kenji Ono, Hiromi Suzuki, Makoto Sawada, Makoto Moriya, Wataru Sakamoto, Toshinobu Yogo

SMALL Vol. 6 ( 21 ) page： 2384 - 2391 2010.11

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY-V C H VERLAG GMBH

Red blood cells (RBCs) are able to avoid filtration in the spleen to prolong their half-time in the body because of their flexibility and unique shape, or a concave disk with diameter of some 10 mu m. In addition, they can flow through capillary blood vessels, which are smaller than the diameter of RBCs, by morphing into a parachute-like shape. In this study, flexible RBC-like polymer particles are synthesized by electrospraying based on electrospinning. Furthermore, magnetite nanoparticles and fluorescent dye are encapsulated in the particles via in situ hydrolysis of an iron-organic compound in the presence of celluloses. The superparamagnetic behavior of the particles is confirmed by low-temperature magnetic measurements. The particles exhibited not only a dark contrast in magnetic resonance imaging (MRI), but also effective fluorescence. The RBC-like particles with flexibility are demonstrated to have a dual-modality for MRI and fluorescence imaging.

DOI： 10.1002/smll.201000399

Correlation between FEPPA uptake and microglia activation in 6-OHDA injured rat brain Invited Reviewed

Kentaro Hatano, Takashi Yamada, Hiroshi Toyama, Gen Kudo, Masahiko Nomura, Hiromi Suzuki, Masanori Ichise, Alan A. Wilson, Makoto Sawada, Takashi Kato, Kengo Ito

NEUROIMAGE Vol. 52 page： S138 - S138 2010.8

High-frequency, magnetic-field-responsive drug release from magnetic nanoparticle/organic hybrid based on hyperthermic effect.

HAYASHI K, ONO K, SUZUKI H, SAWADA M, MORIYA M, SAKAMOTO W, YOGO T

ACS applied materials & interfaces Vol. 2 ( 7 ) page： 1903-1911 2010.7

One-Pot Biofunctionalization of Magnetic Nanoparticles via Thiol-Ene Click Reaction for Magnetic Hyperthermia and Magnetic Resonance Imaging Invited Reviewed

Hayashi Koichiro, Ono Kenji, Suzuki Hiromi, Sawada Makoto, Moriya Makoto, Sakamoto Wataru, Yogo Toshinobu

CHEMISTRY OF MATERIALS Vol. 22 ( 12 ) page： 3768 - 3772 2010.6

Delayed neural damage is induced by iNOS-expressing microglia in a brain injury model Invited Reviewed

Kenji Ono, Hiromi Suzuki, Makoto Sawada

NEUROSCIENCE LETTERS Vol. 473 ( 2 ) page： 146 - 150 2010.4

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER IRELAND LTD

Most CNS diseases begin with inflammation with subsequent neural damage eventually occurring; however, the process leading from the onset of inflammation to neural damage remains obscure. We used an artificial brain injury mouse model and examined how neural damage occurred in the brain parenchyma. The damaged area in each mouse was clearly observed by magnetic resonance imaging (MRI), and the progression of damage was observed to occur in a biphasic manner (acute damage, within 1 week; delayed damage, after 2 weeks). We found that the delayed neural damage was absent in iNOS-deficient mice (iNOS-KO mice). Then, we analyzed brain tissues and determined that delayed neural damage was accompanied by an increase in the levels of NO end products and iNOS expression, with accumulation of iNOS-expressing microglia around the injured area. In addition, the expression of IL-1 beta mRNA was increased in areas affected by acute damage, but not in those affected by delayed damage. These findings suggest that delayed neural damage might arise from NO production by iNOS-expressing activated microglia and that such activated microglia might become a therapeutic target for many CNS diseases. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

DOI： 10.1016/j.neulet.2010.02.041

Two activated stages of microglia and PET imaging of peripheral benzodiazepine receptors with [^<11>C]PK11195 in rats Invited Reviewed

ITO Fumitaka, TOYAMA Hiroshi, KUDO Gen, SUZUKI Hiromi, HATANO Kentaro, ICHISE Masanori, KATADA Kazuhiro, ITO Kengo, SAWADA Makoto

Vol. 24 ( 3 ) page： 163 - 169 2010.4

Delayed neural damage is induced by iNOS-expressing microglia in a brain injury model Reviewed

ONO Kenji, SUZUKI Hiromi, SAWADA Makoto

Neuroscience Letters Vol. 473 ( 2 ) page： 146-150 2010.4

Two activated stage of microglia and PET imaging of peripheral benzodiazepine receptors with [11C]PK11195 in rats Invited Reviewed

Ito F, Toyama H, Kudo G, Suzuki H, Hatano K, Ichise M, Katada K, Ito K, Sawada M

Ann Nucl Med Vol. 24 ( 3 ) page： 163 - 169 2010.4

Language：English Publishing type：Research paper (scientific journal)

OBJECTIVE: The transition of microglia from the normal resting state to the activated state is associated with an increased expression of peripheral benzodiazepine receptors (PBR). The extent of PBR expression is dependent on the level of microglial activation. A PBR ligand, [(11)C]PK11195, has been used for imaging of the activation of microglia in vivo. We evaluated whether [(11)C]PK11195 PET can indicate differences of microglial activation between no treatment and lipopolysaccharide (LPS) treatment in a rat artificial injury model of brain inflammation. METHODS: On day 1, a small aliquot of absolute ethanol was injected into the rat right striatum (ST) to produce artificial brain injury. On day 3, MRI scans were performed to evaluate and select rats showing a similar degree of brain injury. Then LPS or vehicle was administered intraperitoneally. On day 4, PET scans were performed after a bolus injection of [(11)C]PK11195. Eleven rats (7 LPS administered rats, 4 LPS non-administered rats) were evaluated. We used uptake ratios of the integral of right and left striatum from 0 to 60 min as an estimate of PBR distribution volume (V (60)). The number of activated microglia and mRNA expression of inflammatory cytokines (TNFalpha, IL-1beta) were assessed by isolectin-B4 staining and RT-PCR, respectively. RESULTS: Right/left ST V (60) ratios of LPS group were significantly higher than those of non-LPS group (P < 0.03). Although there were no significant differences in the number of activated microglia between the two groups, LPS group showed higher expression of inflammatory cytokines (TNFalpha, IL-1beta) than the non-treated group indicating that further activation was induced by LPS treatment. CONCLUSION: The results suggest that intensity of PBR signals in [(11)C]PK11195 PET may be related to the level of microglial activation rather than the number in activated microglia at least in an artificial brain injury model.

DOI： 10.1007/s12149-009-0339-0

Comparison of the neurological sequelae after rapid correction of hyponatremia between by vasopressin receptor antagonist mozavaptan (OPC-31260) and by hypertonic saline in rats Invited Reviewed

Suzuki, H; Sugimura, Y; Iwama, S; Nagasaki, H; Arima, H; Oiso, Y

ENDOCRINE JOURNAL Vol. 57 page： S531 - S531 2010.3

Neuroprotective and Neurotoxic Phenotypes of Activated Microglia in Neonatal Mice with Respective MPTP- and Ethanol-Induced Brain Injury. Reviewed

Sawada H, Suzuki H, Nagatsu T, Sawada M.

Neuro-degenerative Diseases Vol. 7 ( 1-3 ) page： 64-67 2010.2

Minocycline prevents osmotic demyelination syndrome by inhibiting the activation of microglia. Reviewed

SUZUKI H, SUGIMURA Y, IWAMA S, SUZUKI H, OZAKI N, NAGASAKI H, ARIMA H, SAWADA M, OISO Y.

Journal of the American Society of Nephrology Vol. 21 ( 12 ) page： 2090-2098 2010

Control of activation in ChR2-expressing astrocytes by blue light exposure Invited Reviewed

Kenji Ono, Madoka Higa, Kaori Tabata, Hiromi Suzuki, Makoto Sawada

NEUROSCIENCE RESEARCH Vol. 68 page： E57 - E57 2010

Gene expression profiling of microglia from the demyelinative lesions in osmotic demyelination syndrome rats Invited Reviewed

Yoshihisa Sugimura, Haruyuki Suzuki, Shintaro Iwama, Hiromi Suzuki, Atsushi Kiyota, Makoto Sawada, Yutaka Oiso

NEUROSCIENCE RESEARCH Vol. 68 page： E199 - E199 2010

Neuroprotective and Neurotoxic Phenotypes of Activated Microglia in Neonatal Mice with Respective MPTP- and Ethanol-Induced Brain Injury Invited Reviewed

Hirohide Sawada, Hiromi Suzuki, Toshiharu Nagatsu, Makoto Sawada

NEURODEGENERATIVE DISEASES Vol. 7 ( 1-3 ) page： 64 - 67 2010

Language：English Publishing type：Research paper (scientific journal) Publisher：KARGER

Activated microglia play important roles in the inflammatory process and progression in Parkinson's disease. These cells produce various cytokines, nitric oxide, and neurotrophins, which are pleiotropic in their action, i.e., neuroprotective or neurotoxic. In an in vivo study on a mouse model with nigrostriatal lesions produced by the administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), microglia activated by systemic lipopolysaccharide (LPS) were neurotoxic toward dopamine neurons in aged mice, but unexpectedly, neuroprotective in neonatal mice. In contrast to microglia in the MPTP model, LPS-activated microglia in neonatal mice in a model made by the stereotaxic injection of ethanol into the striatum were neurotoxic, and systemic LPS administration in the ethanol-injury model caused marked increases both in the volume of necrotic lesions and in the number of degenerative neurons in the striatum. Thus, activated microglia in the neonatal mouse brain play either a neuroprotective or neurotoxic role depending on the type of brain injury. Copyright (C) 2010 S. Karger AG, Basel

DOI： 10.1159/000285508

小動物における定量的画像解析 Invited Reviewed

外山宏, 旗野健太郎, 鈴木弘美, 工藤元, 野村昌彦, 山田貴史, 木村裕一, 市瀬正則, 澤田誠

脳循環代謝 Vol. 21 page： 50 - 57 2010

Isolation of Microglia Subpopulations Invited Reviewed

Sawada, M; Suzuki, H

PROTCOLS FOR NEURAL CELL CULTURE, FOURTH EDITION page： 231 - 239 2010

Comparison of [18F]FEPPA and [11C]PBR28, novel peripheral benzodiazepine receptor ligands for PET, in a rat model of neuroinflammation Invited Reviewed

Toyama, H; Hatano, K; Suzuki, H; Kudo, G; Ichise, M; Wilson, A; Yamada, T; Katada, K; Sawada, M; Ito, K

JOURNAL OF NUCLEAR MEDICINE Vol. 50 2009.5

Protective roles of brain-migrated immature bone marrow cells against NO-dependent neurotoxicity in a brain injury model Invited Reviewed

Ono Kenji, Yamamoto Naho, Suzuki Hiromi, Sawada Makoto

NEUROSCIENCE RESEARCH Vol. 65 page： S43 - S43 2009

A PRACTICAL PREPARATION OF [18F]FEPPA USING A PROTIC SOLVENT SYSTEM Invited Reviewed

Hatano, K; Toyama, H; Yamada, T; Kudo, G; Suzuki, H; Ichise, M; Wilson, AA; Sawada, M; Ito, K

JOURNAL OF LABELLED COMPOUNDS & RADIOPHARMACEUTICALS Vol. 52 page： S273 - S273 2009

Neuroprotective or neurotoxic phenotypes of activated microglia in neonatal mice in neuronal injuries Invited Reviewed

Hirohide Sawada, Hiromi Suzuki, Toshiharu Nagatsu, Makoto Sawada

NEUROSCIENCE RESEARCH Vol. 65 page： S118 - S118 2009

Increase in hemokinin-1 mRNA in the spinal cord during the early phase of a neuropathic pain state

MATSUMURA T, SAKAI A, NAGANO M, SAWADA M, SUZUKI H, UMINO M, SUZUKI H

British Journal of Pharmacology Vol. 155 ( 5 ) page： 767-774 2008.11

Blockade of microglial glutamate release protects against ischemic brain injury Invited Reviewed

Hideyuki Takeuchi, Shijie Jin, Hiromi Suzuki, Yukiko Doi, Jianfeng Liang, Jun Kawanokuchi, Tetsuya Mizuno, Makoto Sawada, Akio Suzumura

EXPERIMENTAL NEUROLOGY Vol. 214 ( 1 ) page： 144 - 146 2008.11

Language：English Publishing type：Research paper (scientific journal) Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE

Glutamate released by activated microglia induces excito-neurotoxicity and may contribute to neurodegeneration in numerous neurological diseases including ischemia, inflammation, epilepsy, and neurodegenerative diseases. We observed that the gap junction blocker carbenoxolone (CBX) or the glutaminase inhibitor 6-diazo-5-oxo-i-norleucine (DON) decreased glutamate release from activated microglia and rescued neuronal death in a dose-dependent manner in vitro. In gerbils, treatment with CBX or DON also prevented the delayed death of hippocampal neurons following transient global ischemia. Thus, blockade of microglial glutamate release may be an effective therapeutic strategy against neurodegeneration after ischemic injury. (C) 2008 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.expneurol.2008.08.001

In vivo imaging of microglial activation using a peripheral benzodiazepine receptor ligand: [11C]PK-11195 and animal PET following ethanol injury in rat striatum. Reviewed

Increase in hemokinin-1 mRNA in the spinal cord during the early phase of a neuropathic pain state Invited Reviewed

Matsumura, T; Sakai, A; Nagano, M; Sawada, M; Suzuki, H; Umino, M; Suzuki, H

BRITISH JOURNAL OF PHARMACOLOGY Vol. 155 ( 5 ) page： 767 - 774 2008.11

Toyama H, Hatano K, Suzuki H, Ichise M, Momosaki S, Kudo G, Ito F, Kato T, Yamaguchi H, Katada K, Sawada M, Ito K

Annals of nuclear medicine Vol. 22 ( 5 ) page： 417 - 424 2008.6

Expression of cytokines and neurotrophins after acute subarachnoid hemorrhage Invited Reviewed

Sehba, FA; Flores, R; Ono, K; Suzuki, H; Sawada, SM; Kanzawa, T

STROKE Vol. 39 ( 2 ) page： 650 - 650 2008.2

Enhancement of glioma formation and growth by brain-migrated immature bone marrow cells Invited Reviewed

Kenji Ono, Taiki Furukawa, Hiromi Suzuki, Emi Sato, Makoto Sawada

NEUROSCIENCE RESEARCH Vol. 61 page： S276 - S276 2008

脳の標的化画像診断-PETによる活性化ミクログリアの分子イメージング- Invited Reviewed

外山宏, 工藤元, 伊藤文隆, 片田和広, 大橋正男, 中根正人, 籏野健太郎, 加藤隆司, 伊藤健吾, 鈴木弘美, 澤田誠, 市瀬正則

21世紀COE プログラム、超低侵襲標的化診断治療開発センター研究成果報告書 page： 87 - 88 2008

In-vivo imaging of microglial activation using a novel peripheral benzodiazepine receptor ligand, F-18-FEPPA and animal PET following 6-OHDA injury of the rat striatum; A comparison with C-11-PK11195 Invited Reviewed

Kudo Gen, Toyama H., Hatano K., Suzuki H., Wilson A. A., Ichise M., Ito F., Kato T., Katada K., Sawada M., Ito K.

NEUROIMAGE Vol. 41 page： T94 - T94 2008

動物PETによるラット線状体障害モデルにおけるミクログリア毒性転換の検討 Invited Reviewed

鈴木弘美, 外山宏, 籏野健太郎, 工藤元, 伊藤文隆, 小野健治, 加藤隆司, 伊藤健吾, 澤田誠

バイオイメージング Vol. 16 ( 2 ) page： 93 - 94 2007.10

Activated microglia affect the nigro-striatal dopamine neurons differently in neonatal and aged mice treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine Reviewed

Hirohide Sawada, Ryohei Hishida, Yoko Hirata, Kenji Ono, Hirorni Suzuki, Shin-ichi Muramatsu, Imaharu Nakano, Toshiharu Nagatsu, Makoto Sawada

JOURNAL OF NEUROSCIENCE RESEARCH Vol. 85 ( 8 ) page： 1752 - 1761 2007.6

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY-LISS

Microglia play an important role in the inflammatory process that occurs in Parkinson's disease (PD). Activated microglia produce cytokines and neurotrophins and may have neurotoxic or neurotrophic effects. Because microglia are most proliferative and easily activated during the neonatal period, we examined the effects of neonatal microglia activated with lipopolysaccharide (LPS) on the nigro-striatal dopamine neurons in mice treated with 1-methyl-4-phenyl-1 2,3,6-tetrahyd ropyridine (MPTP), in comparison with activated microglia from the aged mice. By MPTP administration to neonatal mice, the number of dopamine neurons in the substantia nigra (SN) was decreased significantly, whereas that in the mice treated with LPS and MPTP was recovered to normal, along with significant microglial activation. Tyrosine hydroxylase (TH) activity, the levels of dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC), and the levels of pro-inflammatory cytokines IL-1 beta and IL-6 in the midbrain were elevated in the neonates treated with LPS and MPTR On the contrary, although the number of dopamine neurons in the 60-week-old mice treated with MPTP was also decreased significantly, the microglial activation by LPS treatment caused a further decrease in their number. These results suggest that the activated microglia in neonatal mice are different from those in aged mice, with the former having neurotrophic potential toward the dopamine neurons in the SN, in contrast to the neurotoxic effect of the latter. (c) 2007 Wiley-Liss, Inc.

DOI： 10.1002/jnr.21241

J-GLOBAL

Neuroprotective effect of exogenous microglia in global brain ischemia. Invited Reviewed

Imai F, Suzuki H, Oda J, Ninomiya T, Ono K, Sano H, Sawada M

Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism Vol. 27 ( 3 ) page： 488 - 500 2007.3

[Targeting and imaging of brain-specific cell migration]. Invited Reviewed

Sawada M, Ono K, Suzuki H

Nihon rinsho. Japanese journal of clinical medicine Vol. 65 ( 2 ) page： 213 - 8 2007.2

N-benzyl-2-(6,8-dichloro-2-(4-chlorophenyl)imidazo[1,2-a]pyridin-3-yl)-N-(6-(7-nitrobenzo[c][1,2,5]oxadiazol-4-ylamino)hexyl)acetamide as a new fluorescent probe for peripheral benzodiazepine receptor and microglial cell visualization Invited Reviewed

Valentino Laquintana, Nunzio Denora, Angela Lopedota, Hiromi Suzuki, Makoto Sawada, Mariangela Serra, Giovanni Biggio, Andrea Latrofa, Giuseppe Trapani, Gaetano Liso

BIOCONJUGATE CHEMISTRY Vol. 18 ( 5 ) page： 1397 - 1407 2007

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC

The aim of this work was to develop new fluorescent probes for the localization and function of the peripheral benzodiazepine receptor (PBR). This receptor is primarily expressed on the mitochondria, and it is overexpressed in a variety of different states including glioma, breast cancer, Alzeheimer's disease, and activated microglia. For the mentioned purpose, imidazopyridine and imidazopyrimidine compounds 5-20 were synthesized, and their affinity for PBR was determined. Although some intrinsically fluorescent imidazopyrimidine compounds 12-20 possess good binding affinity, they cannot be used for visualizing PBR due to their unfavorable fluorescence characteristics. Among the imidazopyridine-7-nitrofurazan conjugates 5-11, compound 10 was the most active, and it was found to stain live Ra2 microglial cells effectively. An in vivo biodistribution study carried out on compound 10 showed that this imidazopyridine derivative, injected in the carotid artery, is able to penetrate to liver parenchyma, whereas fluorescein isothiocyanate labeled dextran (FITC-dextran), used as a control dye, hardly penetrated from blood vessels to tissues. On the other hand, as for the distribution to brain, the patterns of staining with 10 and FITC-dextran are similar, indicating that both of them hardly penetrate into the brain because of the existence of the blood-brain barrier. The obtained results indicate that compound 10 represents a new useful fluorescent probe for visualization of activated microglia and PBR.

DOI： 10.1021/bc060393c

P2-16 新生時由来ミクログリアの活性化がパーキンソン病モデルマウスの黒質ドーパミンニューロンに対して神経保護的にはたらく可能性(脳神経,一般演題,第48回日本組織細胞化学会総会(第8回日中合同組織細胞化学セミナー) 第39回日本臨床分子形態学会総会合同学術集会) Invited Reviewed

澤田浩秀, 菱田良平, 平田洋子, 小野健治, 鈴木弘美, 村松慎一, 中野今治, 永津俊治, 澤田誠

日本組織細胞化学会総会プログラムおよび抄録集 ( 48 ) 2007

アルツハイマー病早期診断マーカーのための活性化ミクログリアの画像化-PETによる末梢性ベンゾジアゼピン受容体イメージング- Invited Reviewed

外山宏, 工藤元, 伊藤文隆, 片田和広, 大橋正男, 中根正人, 籏野健太郎, 加藤隆司, 伊藤健吾, 鈴木弘美, 澤田誠, 市瀬正則

医科学応用研究財団研究報告 26 page： 415 - 420 2007

The intra-arterial injection of microglia protects hippocampal CA1 neurons against global ischemia-induced functional deficits in rats Invited Reviewed

Y. Hayashi, Y. Tomimatsu, H. Suzuki, J. Yamada, Z. Wu, H. Yao, Y. Kagamiishi, N. Tateishi, M. Sawada, H. Nakanishi

NEUROSCIENCE Vol. 142 ( 1 ) page： 87 - 96 2006.9

Language：English Publishing type：Research paper (scientific journal) Publisher：PERGAMON-ELSEVIER SCIENCE LTD

In the present study, we have attempted to elucidate the effects of the intra-arterial injection of microglia on the global ischemia-induced functional and morphological deficits of hippocampal CA1 neurons. When PKH26-labeled immortalized microglial cells, GMIR1, were injected into the subclavian artery, these exogenous microglia were found to accumulate in the hippocampus at 24 h after ischemia. In hippocampal slices prepared from medium-injected rats subjected to ischemia 48 h earlier, synaptic dysfunctions including a significant reduction of synaptic responses and a marked reduction of long-term potentiation (LTP) of the CA3-CA1 Schaffer collateral synapses were observed. At this stage, however, neither significant neuronal degeneration nor gliosis was observed in the hippocampus. At 96 h after ischemia, there was a total loss of the synaptic activity and a marked neuronal death in the CA1 subfield. In contrast, the basal synaptic transmission and LTP of the CA3-CA1 synapses were well preserved after ischemia in the slices prepared from the microglia-injected animals. We also found the microglial-conditioned medium (MCM) to significantly increase the frequency of the spontaneous postsynaptic currents of CA1 neurons without affecting the amplitude, thus indicating that MCM increased the provability of the neurotransmitter release. The protective effect of the intra-arterial injected microglia against the ischemia-induced neuronal degeneration in the hippocampus was substantiated by immunohistochemical and immunoblot analyses. Furthermore, the arterial-injected microglia prevented the ischemia-induced decline of the brain-derived neurotrophic factor (BDNF) levels in CA1 neurons. These observations strongly suggest that the arterial-injection of microglia protected CA1 neurons against the ischemia-induced neuronal degeneration. The restoration of the ischemia-induced synaptic deficits and the resultant reduction of the BDNF levels in CA1 neurons, possibly by the release of diffusible factor(s), might thus contribute to the protective effect of the arterial-injection of microglia against ischemia-induced neuronal degeneration. (c) 2006 IBRO. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.neuroscience.2006.06.003

In vivo imaging of microglial activation using a peripheral benzodiazepine receptor ligand, [11C]PK11195 and animal PET following implantation of cultured activated microglia into rat striatum Invited Reviewed

The intra-arterial injection of microglia protects hippocampal CA1 neurons against global ischemia-induced functional deficits in rats

HAYASHI Y, TOMIMATSU Y, SUZUKI H, YAMADA J, WU Z, YAO H, KAGAMIISI Y, TAKEISHI N, SAWADA M, NAKANISHI H

Neuroscience Vol. 142 ( 1 ) page： 87-96 2006.9

Modulations of muscle protein metabolism by branched-chain amino acids in normal and muscle-atrophying rats. Invited Reviewed

Kobayashi H, Kato H, Hirabayashi Y, Murakami H, Suzuki H

The Journal of nutrition Vol. 136 ( 1 Suppl ) page： 234S - 6S 2006.1

Activated microglia affect the nigro-striatal dopamine neurons differently in neonatal and aged mice treated with MPTP Invited Reviewed

Hirohide Sawada, Ryohei Hishida, Yoko Hirata, Kenji Ono, Hiromi Suzuki, Shin-ichi Muramatsu, Imaharu Nakano, Kunihiro Tsuchida, Toshiharu Nagatsu, Makoto Sawada

NEUROSCIENCE RESEARCH Vol. 55 page： S201 - S201 2006

Kudo, G; Toyama, H; Hatano, K; Suzuki, H; Ichise, M; Ito, F; Kato, T; Sawada, M; Katada, K; Ito, K

NEUROIMAGE Vol. 31 page： T148 - T148 2006

活性型ミクログリアの In Vivo イメージング Invited Reviewed

鈴木弘美, 外山宏, 工藤元, 籏野健太郎, 関亦克彦, 小野健治, 中根正人, 加藤隆司, 伊藤健吾, 澤田誠

バイオイメージング Vol. 14 ( 3 ) page： 129 - 130 2005.9

A lentiviral expression system demonstrates that L*protein of Theiler's murine encephalomyelitis virus(TMEV) is essential for virus growth in a murine macrophage-like cell line.

HIMEDA T, OHARA Y, ASAKURA K, KONTANI Y, MURAKAMI M, SUZUKI H, SAWADA M

Virus Research Vol. 108 ( 1-2 ) page： 23-28 2005.3

Cytokine production of activated microglia and decrease in neurotrophic factors of neurons in the hippocampus of Lewy body disease brains.

IMAMURA K, HISHIKAWA N, ONO K,SUZUKI H, SAWADA M, NAGATSU T, YOSHIDA M, HASHIZUME Y

Acta Neuropathologica Vol. 109 ( 2 ) page： 141-150 2005.2

Cytokine production of activated microglia and decrease in neurotrophic factors of neurons in the hippocampus of Lewy body disease brains Invited Reviewed

K Imamura, N Hishikawa, K Ono, H Suzuki, M Sawada, T Nagatsu, M Yoshida, Y Hashizume

ACTA NEUROPATHOLOGICA Vol. 109 ( 2 ) page： 141 - 150 2005.2

Language：English Publishing type：Research paper (scientific journal) Publisher：SPRINGER

Dementia is a frequent complication of Parkinson's disease (PD) and usually occurs late in the protracted course of the illness. We have already reported numerous MHC class II-positive microglia in the hippocampus in PD patients, and that this phenomenon may be responsible for functional changes in the neurons and the cognitive decline in PD patients. In this study, we have investigated the distribution of activated microglia and the immunohistochemical and the mRNA expression of several cytokines and neurotrophic factors of the hippocampus in PD and dementia with Lewy bodies (DLB). The brains from five cases of PD and five cases of DLB that were clinically and neuropathologically diagnosed, and those from four normal controls (NC) were evaluated by immunohistochemistry using anti-HLA-DP, -DQ, -DR (CR3/43), anti-alpha-synuclein, anti-brain-derived neurotrophic factor (BDNF), and anti-glial fibrillary acidic protein antibodies. In addition, the mRNA expressions of cytokines (IL-1 alpha, IL-1 beta, TNF-alpha, IL-6, TGF-beta) and neurotrophic factors (BDNF, GDNF, NGF, NT-3) of these brains were evaluated by the reverse transcription-PCR method. MHC class II-positive microglia were distributed diffusely in the hippocampus of PD and DLB brains. Although the cytoplasm of pyramidal and granular cells of the hippocampus in NC brains was strongly stained by anti-BDNF antibodies, it was only weakly stained in PD and DLB brains. The mRNA expression of IL-6 was significantly increased in the hippocampus of PD and DLB brains, and that of BDNF was significantly decreased in the hippocampus of DLB brains. The increased number of activated microglia and the production of neurotrophic cytokines such as IL-6, together with the decreased expression of the neurotrophic factors of neurons in the hippocampus of PD and DLB brains, may be related to functional cellular changes associated with dementia.

DOI： 10.1007/s00401-004-0919-y

Murine lymph node-derived stromal cells effectively support survival but induce no activation/proliferation of peripheral resting T cells in vitro Invited Reviewed

Zhou YW, Aritake S, Endharti AT, Wu JH, Hayakawa A, Nakashima I, Suzuki H

IMMUNOLOGY Vol. 109 ( 4 ) page： 496 - 503 2003.8

Preservation of hematopoietic properties in transplanted bone marrow cells in the brain. Invited Reviewed

Ono K, Yoshihara K, Suzuki H, Tanaka KF, Takii T, Onozaki K, Sawada M

Journal of neuroscience research Vol. 72 ( 4 ) page： 503 - 7 2003.5

Existence of functional beta(1)- and beta(2)-adrenergic receptors on microglia

KF Tanaka, H Kashima, H Suzuki, K Ono, M Sawada

JOURNAL OF NEUROSCIENCE RESEARCH Vol. 70 ( 2 ) page： 232 - 237 2002.10

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY-LISS

We examined the expression and function of beta-adrenergic receptor (beta-AR) subtypes in both isolated primary rat microglia and a rat microglial cell line. RTPCR analyses revealed that microglia expressed beta(1)- and beta(2)-ARs but not beta(3)-ARs, whereas rat primary peritoneal macrophages expressed only beta(2)-ARs. Stimulation of beta-ARs on microglia by norepinephrine (NE) resulted in an increase in the level of intracellular cAMP and the subsequent expression of interleukin-1beta mRNA. These effects were prevented by propranolol. Similar results were obtained with other selective beta(1)-AR agonists and antagonists. beta(2)-ARs on microglia were also functional. It is possible that noradrenergic innervations participate in the control of microglial functions via beta(1)-ARs on microglia in the brain, because NE has high affinity for beta(1)- and beta(3)-ARs but little or no affinity for beta(2)-ARs. It seems physiologically significant that microglia can be controlled by NE, which predominates over epinephrine in the brain, whereas macrophages in peripheral tissues can be controlled by epinephrine, which is at higher levels in peripheral tissues. (C) 2002 Wiley-Liss, inc.

DOI： 10.1002/jnr.10399

Exogenous microglia enter the brain and migrate into ischaemic hippocampal lesions

Modes of activation of mitogen-activated protein kinases and their roles in cepharanthine-induced apoptosis in human leukemia cells Invited Reviewed

Wu JH, Suzuki H, Akhand AA, Zhou YW, Hossain K, Nakashima I

CELLULAR SIGNALLING Vol. 14 ( 6 ) page： 509 - 515 2002.6

Brain-specific migration and protective roles in brain damage of microglia - A new therapeutic approach for catecholamine neuronal disfunctions Reviewed

M Sawada, F Imai, H Suzuki

CATECHOLAMINE RESEARCH: FROM MOLECULAR INSIGHTS TO CLINICAL MEDICINE Vol. 53 page： 217 - 220 2002

Preservation of neurotophin expression in microglia that migrate into the gerbil's brain across the blood-brain barrier.

SUZUKI H, IMAI F, KANNO T, SAWADA M

Neuroscience Letters Vol. 312 ( 2 ) page： 95-98 2001.10

Osmotic stress-mediated activation of RET kinases involves intracellular disulfide-bonded dimer formation Invited Reviewed

Takeda K, Kato M, Wu JH, Iwashita T, Suzuki H, Takahashi M, Nakashima I

ANTIOXIDANTS & REDOX SIGNALING Vol. 3 ( 3 ) page： 473 - 482 2001.6

4-hydroxynonenal induces a cellular redox status-related activation of the caspase cascade for apoptotic cell death. Invited Reviewed

Liu W, Kato M, Akhand AA, Hayakawa A, Suzuki H, Miyata T, Kurokawa K, Hotta Y, Ishikawa N, Nakashima I

Journal of cell science Vol. 113 ( Pt 4) page： 635 - 41 2000.2

Molecular Mechanism of Activation and Superactivation of Ret Tyrosine Kinases by Ultraviolet Light Irradiation Invited Reviewed

Kato Masashi, Iwashita Toshihide, Akhand Anwarul A., Liu Wei, Takeda Kozue, Takeuchi Kei, Yoshihara Motoi, Hossain Khaled, Wu Jianghong, Du Jun, Oh Chanho, Kawamoto Yoshiyuki, Suzuki Haruhiko, Takahashi Masahide, Nakashima Izumi

ANTIOXIDANTS & REDOX SIGNALING Vol. 2 ( 4 ) page： 841 - 850 2000

Normal regulatory alpha/beta T cells effectively eliminate abnormally activated T cells lacking the interleukin 2 receptor beta in vivo Invited Reviewed

Suzuki H, Zhou YW, Kato M, Mak TW, Nakashima I

JOURNAL OF EXPERIMENTAL MEDICINE Vol. 190 ( 11 ) page： 1561 - 1571 1999.12

Exogenous microglia enter the brain and migrate into ischaemic hippocampal lesions.

IMAI F, SAWADA M, SUZUKI H, ZLOKOVIC BV, KOJIMA J, KUNO S, NAGATSU T, NITATORI T, UCHIYAMA Y, KANNNO T

Neuroscience Letters Vol. 272 ( 2 ) page： 127-130 1999.9

F Imai, M Sawada, H Suzuki, BV Zlokovic, J Kojima, S Kuno, T Nagatsu, T Nitatori, Y Uchiyama, T Kanno

NEUROSCIENCE LETTERS Vol. 272 ( 2 ) page： 127 - 130 1999.9

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCI IRELAND LTD

We compared migration of systemically injected microglia into normal brain vs. ischaemic brain using a model of ischaemic hippocampal lesion. Microglia were labeled by a fluorescent dye using our standard phagocytosis procedure of microscopic particles and then injected intra-arterially into Mongolian gerbils subjected to ischaemia reperfusion neuronal injury. Delayed death of pyramidal neurons was confirmed by conventional histological analysis and dUTP nick end labeling (TUNEL) method. Clusters of dye-tagged cells migrating into the hippocampal ischaemic lesions were confirmed histochemically to be microglia. Since peripherally injected microglia exhibit specific affinity for ischaemic brain lesions and does not exacerbate ischaemic neuronal injury in the present model, we suggest that microglia may have a potential to be used as a piggy-back ride to deliver therapeutic genes and/or drugs for CNS repair following transitory global ischaemic insult. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.

DOI： 10.1016/S0304-3940(99)00592-3