一般口演（若手道場）

一般口演（若手道場）若手道場　疾患モデル Wakate Dojo: Disorder Model 座長：七田崇（東京都医学総合研究所）・金子奈穂子（名古屋市立大学）

2022年7月1日　15:00～15:15　沖縄コンベンションセンター会議場A2　第7会場 2WD07a2-01 Microbiome-derived short-chain fatty acid metabolites modulate transcriptional homeostasis and cocaine-seeking after abstinence. Katherine R Meckel(1,2), Rebecca S Hofford(2,3), Arthur Godino(1,2), Emily G Peck(4), Erin S Calipari(5), Drew D Kiraly(1,2,3) 1. Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, 2. The Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, 3. Department of Psychiatry, Icahn School of Medicine at Mount Sinai, 4. Department of Physiology and Pharmacology, Wake Forest School of Medicine, 5. Department of Pharmacology, Vanderbilt University Keyword:* Cocaine, Microbiome, Substance Use Disorders, Brain-Gut Axis Psychostimulant use disorder represents a public health crisis leading to tremendous morbidity. Growing evidence suggests gut bacteria and their metabolites significantly affect brain and behavior in animal models of psychiatric disease. Bacterially-derived short-chain fatty acid (SCFA) metabolites are implicated in altering transcriptional profiles and chromatin structure in the brain. However, the role of gut microbiome and its metabolites in modulating cocaine-seeking behavior after prolonged abstinence is unknown. Given that prevention of relapse following abstinence is the most clinically challenging issue in treating patients with substance use disorders, studies examining the effects of microbiome manipulations in relapse relevant models are critical for the development of translational strategies in this space. For the current studies, depletion of gut bacteria and their metabolites was induced in Sprague-Dawley rats via addition of antibiotics in their drinking water and compared to untreated controls. Rats were trained to self-administer cocaine and subjected to either within-session threshold testing to evaluate motivation for cocaine at a range of doses or 21 days of abstinence followed by a cue-induced cocaine-seeking task to model relapse behavior. Nucleus accumbens tissue was then isolated and processed for RNA-sequencing analysis. We found that animals lacking a complex gut microbiome showed significantly increased cocaine-seeking behaviors and altered expression of synaptic plasticity genes. Molecular analyses further revealed marked changes in activity-dependent gene expression in antibiotic-treated rats compared to controls. To identify specific mechanistic contributions of SCFA, the metabolites were replenished via addition to the drinking water in animals with depleted gut microbiomes. In the absence of a normal microbiome, repletion of bacterially-derived SCFA metabolites reversed the behavioral and molecular changes associated with microbiome depletion. Together, these findings suggest that gut bacteria via their metabolites may serve as homeostatic regulators of gene expression in the brain, and suggest the microbiome has potential as a translational research target.		2022年7月1日　15:15～15:30　沖縄コンベンションセンター会議場A2　第7会場 2WD07a2-02 青斑核ノルアドレナリン神経活動を持続的に抑制するプロスタグランジンE₂の生理機能 Physiological function of prostaglandin E₂-induced sustained suppression of activity of noradrenergic neurons in the locus coeruleus 向井康敬(1,2)、ラザルスミハエル(3)、永井健治(4)、田中謙二(5)、山中章弘(1,2) 1. 名古屋大学環境医学研究所神経系分野2、2. 名古屋大学大学院医学系研究科神経性調節学、3. 筑波大学国際統合睡眠医科学研究機構、4. 大阪大学産業科学研究所生体分子機能科学、5. 慶応大学医学部精神・神経科学 Yasutaka Mukai(1,2), Michael Lazarus(3), Takeharu Nagai(4), Kenji F Tanaka(5), Akihiro Yamanaka(1,2) 1. Neuroscience 2, RIEM, Nagoya University, 2. Dept of Neural Regulation, Grad Sch Med, Nagoya Univ, Nagoya, Japan, 3. WPI-IIIS, Tsukuba Univ, Tsukuba, Japan, 4. Dept Biomol Sci and Eng, ISIR, Osaka Univ, Osaka, Japan, 5. Dept of Neuropsychiatry, Sch of Med, Keio Univ, Tokyo, Japan Keyword: Noradrenergic neurons, Locus coeruleus, Stress, Calcium imaging Noradrenergic neurons in the locus coeruleus (LC-NA neurons) play various important roles in multiple physiological functions, such as wakefulness, attention and memory. Time duration required for these function ranges from seconds or minutes to hours or even days. However, bioactive substances which affect the activity in minutes- to hours-time scale have been still elusive. Recently we developed a screening method to identify substances which affect the activity of specific neurons in minutes- to hours-time scale (Mukai et al., Sci Rep, 2020). Therefore, we applied this method to identify substances which affect activity of LC-NA neurons. We generated a transgenic mouse strain which expresses genetically encoded calcium indicator Yellow Cameleon-Nano50 (YC) in NA neurons by using TetO YC mouse strain crossed with dopamine-beta hydroxylase (DβH)-tetracyclin transactivator (tTA) mouse strain (YCD mouse). We prepared acute brain slices from YCD mice, and measured calcium concentration change in hours-time scale after 2 minutes of each candidate substance application. We screened 57 substances, and found that prostaglandin E₂ (PGE₂; 100 μM) strongly and sustainedly decreased intracellular calcium concentration ([Ca²⁺]_i) for more than an hour. We further explored for a responsible receptor of PGE₂ by generating a transgenic mouse strain in which prostaglandin EP3 receptor (EP3R) is conditionally knocked out (cKO) in noradrenergic neurons by using EP3R-flox mice strain crossed with noradrenaline transporter (NAT)-Cre recombinase (Cre) strain. We expressed YC by injecting Cre-dependent adeno-associated viral vector into the LC. As a result, strong and sustained decrease of [Ca²⁺]_i was diminished in cKO animals. Thus, we found that EP3R is involved in the PGE₂-induced sustained suppression of activity of LC-NA neurons. In the brain, PGE₂ is known to be produced by psychological and illness stressors. Therefore, we hypothesized that PGE₂ suppresses the activity of LC-NA neurons via EP3R under stress conditions. To reveal the physiological functions, we performed several behavioral experiments in cKO animals with application of stressors. Among them, we found that restraint stress induced longer immobile time in female cKO, and the total amount of rapid-eye movement (REM) sleep in the light phase was shorter in male cKO. We would like to introduce and discuss about our ongoing preliminary results.

2022年7月1日　15:30～15:45　沖縄コンベンションセンター会議場A2　第7会場 2WD07a2-03 神経発達障害に関わるヒストンメチル基転移酵素の機能解析 Functional analyses of a histone methyltransferase related to neurodevelopmental disorders 中村匠(1,2)、中島一夫(1)、吉原亨(3)、高野久楽々(1)、種子島千春(4)、門田満隆(4)、豊島学(1)、小林祐樹(1)、上田順子(1)、糸原重美(1)、吉川武男(1)、工樂樹洋(4)、浅野雅秀(3)、笠原和起(1)、坪井貴司(5)、高田篤(1)、加藤忠史(2) 1. 理化学研究所脳神経科学研究センター、2. 順天堂大学大学院医学研究科、3. 京都大学大学院医学研究科、4. 理化学研究所生命機能科学研究センター、5. 東京大学大学院総合文化研究科 Takumi Nakamura(1,2), Kazuo Nakajima(1), Toru Yoshihara(3), Kurara Takano(1), Chiharu Tanegashima(4), Mitsutaka Kadota(4), Manabu Toyoshima(1), Yuki Kobayashi(1), Junko Ueda(1), Shigeyoshi Itohara(1), Takeo Yoshikawa(1), Shigehiro Kuraku(4), Masahide Asano(3), Takaoki Kasahara(1), Takashi Tsuboi(5), Atsushi Takata(1), Tadafumi Kato(2) 1. RIKEN Center for Brain Science, 2. Juntendo University Graduate School of Medicin, 3. Kyoto University Graduate School of Medicine, 4. RIKEN Center for Biosystems Dynamics Research, 5. Graduate School of Arts and Sciences, The University of Tokyo Keyword: Autism spectrum disorder, neurodevelopmental disorder, histone methyltransferase, single cell RNA-seq In human genetics studies, many loss-of-function mutations on KMT2C, encoding an epigenetic factor that regulates histone 3 lysine 4 (H3K4), have been found in patients with neurodevelopmental disorders (NDD) such as Kleefstra syndrome and autism spectrum disorder (ASD). More recently, a statistically robust association between deleterious mutations of KMT2C and ASD was reported in a large-scale sequencing study (Sattertrom FK et al., Cell 2020). However, the pathophysiological mechanisms of NDD and ASD caused by the reduced KMT2C activity are still unclear. To address this, we generated heterozygous mutant mice of Kmt2c which harbor a frameshift mutation as a high etiological validity model of ASD/NDD by using the CRISPR/Cas9 system. In a battery of behavioral tests, we found significant behavioral alterations, such as social deficiency in three-chamber social interaction test, supporting the face validity of the mutant mice as a model of ASD/NDD. We revealed drastic alterations of transcriptomes in neuroepithelial cells or early radial glia of mutant mice by single-cell RNA-sequencing, which might cause various effects on later differentiated cells of nervous systems. We re-analyzed the data of single nucleus RNA-seq using postmortem brains of patients with ASD (Velmechev D. et al. Science. 2019), and identified that the differential abundance of glial cells, in accordance with the findings of Kmt2c mutant mice. In this presentation, we would like to introduce the candidate molecular pathogenesis of ASD/NDD, especially due to the loss-of-function mutations of KMT2C, shown by the study of genetically modified mice and re-analyses of the previous human genomics data.		2022年7月1日　15:45～16:00　沖縄コンベンションセンター会議場A2　第7会場 2WD07a2-04 慢性社会的敗北ストレスにより誘発されるうつ様行動に脾臓由来の免疫応答が関与する Involvement of spleen-derived immune response in the depression-like behaviors induced by chronic social defeat stress. 小菅愛加(1)、國澤和生(1)、手塚裕之(2)、星雅人(3)、森田那奈架(4)、河合智貴(1)、齋藤邦明(4,5,6)、鍋島俊隆(5,6)、毛利彰宏(1,6) 1. 藤田医科大学大学院保健学研究科レギュラトリーサイエンス分野、2. 藤田医科大学共同利用研究設備サポートセンター細胞機能解析室、3. 藤田医科大学医療科学部医療検査学科基礎病態情報解析学分野、4. 藤田医科大学大学院保健学研究科生体情報検査学分野、5. 藤田医科大学大学院保健学研究科先進診断システム探索研究部門、6. ＮＰＯ法人医薬品適正使用推進機構 Aika Kosuge(1), Kazuo Kunisawa(1), Hiroyuki Tezuka(2), Masato Hoshi(3), Nanaka Morita(4), Tomoki Kawai(1), Kuniaki Saito(4,5,6), Toshitaka Nabeshima(5,6), Akihiro Mouri(1,6) 1. Department of Regulatory Science for Evaluation & Development of Pharmaceuticals & Devices, Fujita Health University Graduate School of Health Sciences, Aichi, Japan, 2. Department of Cellular Function Analysis, Research Promotion and Support Headquarters, Fujita Health University, Aichi, Japan, 3. Department of Biochemical and Analytical Sciences, Fujita Health University, 4. Department of Disease Control and Prevention, Fujita Health University Graduate School of Health Sciences, Aichi, Japan, 5. Advanced Diagnostic System Research Laboratory, Fujita Health University Graduate School of Health Science, Aichi, Japan, 6. Japanese Drug Organization of Appropriate Use and Research (J-DO), Aichi, Japan Keyword: Depression, BBB, inflammation Inflammatory response contributes to the pathogenesis of major depressive disorder (MDD). The levels of pro-inflammatory cytokines are elevated in the serum of MDD patients. However, the precise mechanism of how the peripheral inflammatory response contributes to the development of MDD remains unclear. The spleen is the largest secondary lymphoid organ and hosts a wide range of immunologic functions, including peripheral inflammatory response. In the present study, we investigated the involvement of the spleen in chronic social defeat stress (CSDS)-induced depression-like behavior. The adult C57BL/6J mouse was exposed to an aggressor ICR mouse for 10 consecutive days. One day after the last stress exposure, CSDS reduced the social interaction (SI) ratios in the social interaction test and increased immobility time in the forced swimming test. SI ratio was calculated by dividing the interaction zone time when the social target is present by interaction zone time when the target is absent. The spleen weights in the CSDS mice were significantly increased. The levels of IL-6 in the spleen and serum were significantly increased in CSDS mice. The splenectomy significantly prevented CSDS-induced social impairment. CSDS significantly increased infiltration of Evans Blue dye, a marker of microvascular leakage, with decreased expression of claudin-5 in the cerebellum, suggesting the disruption of cerebellar BBB. Disruption of the blood-brain barrier (BBB) enhanced neuroinflammation response in the brain. Our results suggest that the spleen plays a role in CSDS-induced depressive-like behavior. Splenic-derived IL-6 may disrupt the cerebellar BBB through the decrease of claudin-5 expression. These evidence may be an attractive information for the development of novel antidepressants.