Faculty Profiles - MIZOGUCHI, Hiroyuki

Mice with deficiency in Pcdh15, a gene associated with bipolar disorders, exhibit significantly elevated diurnal amplitudes of locomotion and body temperature Open Access

The Use of Text Mining to Obtain a Historical Overview of Research on Therapeutic Drug Monitoring Open Access

Matsuzaki Tetsuo, Mizoguchi Hiroyuki, Yamada Kiyofumi

Biological and Pharmaceutical Bulletin Vol. 47 ( 11 ) page： 1883 - 1892 2024.11

Language：English Publisher：The Pharmaceutical Society of Japan

Therapeutic drug monitoring (TDM) is a routine clinical practice used to individualize drug dosing to maintain drug efficacy and minimize the consequences of overexposure. TDM is applied to many drug classes, including immunosuppressants, antineoplastic agents, and antibiotics. Considerable effort has been made to establish routine TDM practices for each drug. However, because TDM has been developed within the context of specific drugs, there is insufficient understanding of historical trends within the field of TDM research as a whole. In this study, we employed text-mining approaches to explore trends in the TDM research field. We first performed a PubMed search to determine which drugs and drug classes have been extensively studied in the context of TDM. This investigation revealed that the most commonly studied drugs are tacrolimus, followed by cyclosporine and vancomycin. With regard to drug classes, most studies focused on immunosuppressants, antibiotics, and antineoplastic agents. We also subjected PubMed records of TDM-related studies to a series of text-mining pipelines. Our analyses revealed how TDM research has evolved over the years, thereby serving as a cornerstone for forecasting future research trends.

DOI： 10.1248/bpb.b24-00319

Mori, D; Inami, C; Ikeda, R; Sawahata, M; Urata, S; Yamaguchi, ST; Kobayashi, Y; Fujita, K; Arioka, Y; Okumura, H; Kushima, I; Kodama, A; Suzuki, T; Hirao, T; Yoshimi, A; Sobue, A; Ito, T; Noda, Y; Mizoguchi, H; Nagai, T; Kaibuchi, K; Okabe, S; Nishiguchi, K; Kume, K; Yamada, K; Ozaki, N

TRANSLATIONAL PSYCHIATRY Vol. 14 ( 1 ) page： 216 2024.5

Language：English Publisher：Translational Psychiatry

Genetic factors significantly affect the pathogenesis of psychiatric disorders. However, the specific pathogenic mechanisms underlying these effects are not fully understood. Recent extensive genomic studies have implicated the protocadherin-related 15 (PCDH15) gene in the onset of psychiatric disorders, such as bipolar disorder (BD). To further investigate the pathogenesis of these psychiatric disorders, we developed a mouse model lacking Pcdh15. Notably, although PCDH15 is primarily identified as the causative gene of Usher syndrome, which presents with visual and auditory impairments, our mice with Pcdh15 homozygous deletion (Pcdh15-null) did not exhibit observable structural abnormalities in either the retina or the inner ear. The Pcdh15-null mice showed very high levels of spontaneous motor activity which was too disturbed to perform standard behavioral testing. However, the Pcdh15 heterozygous deletion mice (Pcdh15-het) exhibited enhanced spontaneous locomotor activity, reduced prepulse inhibition, and diminished cliff avoidance behavior. These observations agreed with the symptoms observed in patients with various psychiatric disorders and several mouse models of psychiatric diseases. Specifically, the hyperactivity may mirror the manic episodes in BD. To obtain a more physiological, long-term quantification of the hyperactive phenotype, we implanted nano tag® sensor chips in the animals, to enable the continuous monitoring of both activity and body temperature. During the light-off period, Pcdh15-null exhibited elevated activity and body temperature compared with wild-type (WT) mice. However, we observed a decreased body temperature during the light-on period. Comprehensive brain activity was visualized using c-Fos mapping, which was assessed during the activity and temperature peak and trough. There was a stark contrast between the distribution of c-Fos expression in Pcdh15-null and WT brains during both the light-on and light-off periods. These results provide valuable insights into the neural basis of the behavioral and thermal characteristics of Pcdh15-deletion mice. Therefore, Pcdh15-deletion mice can be a novel model for BD with mania and other psychiatric disorders, with a strong genetic component that satisfies both construct and surface validity.

DOI： 10.1038/s41398-024-02952-6

Phenotypes for general behavior, activity, and body temperature in 3q29 deletion model mice Open Access

Mori, D; Ikeda, R; Sawahata, M; Yamaguchi, S; Kodama, A; Hirao, T; Arioka, Y; Okumura, H; Inami, C; Suzuki, T; Hayashi, Y; Kato, H; Nawa, Y; Miyata, S; Kimura, H; Kushima, I; Aleksic, B; Mizoguchi, H; Nagai, T; Nakazawa, T; Hashimoto, R; Kaibuchi, K; Kume, K; Yamada, K; Ozaki, N

TRANSLATIONAL PSYCHIATRY Vol. 14 ( 1 ) page： 138 2024.3

Language：English Publisher：Translational Psychiatry

Whole genome analysis has identified rare copy number variations (CNV) that are strongly involved in the pathogenesis of psychiatric disorders, and 3q29 deletion has been found to have the largest effect size. The 3q29 deletion mice model (3q29-del mice) has been established as a good pathological model for schizophrenia based on phenotypic analysis; however, circadian rhythm and sleep, which are also closely related to neuropsychiatric disorders, have not been investigated. In this study, our aims were to reevaluate the pathogenesis of 3q29-del by recreating model mice and analyzing their behavior and to identify novel new insights into the temporal activity and temperature fluctuations of the mouse model using a recently developed small implantable accelerometer chip, Nano-tag. We generated 3q29-del mice using genome editing technology and reevaluated common behavioral phenotypes. We next implanted Nano-tag in the abdominal cavity of mice for continuous measurements of long-time activity and body temperature. Our model mice exhibited weight loss similar to that of other mice reported previously. A general behavioral battery test in the model mice revealed phenotypes similar to those observed in mouse models of schizophrenia, including increased rearing frequency. Intraperitoneal implantation of Nano-tag, a miniature acceleration sensor, resulted in hypersensitive and rapid increases in the activity and body temperature of 3q29-del mice upon switching to lights-off condition. Similar to the 3q29-del mice reported previously, these mice are a promising model animals for schizophrenia. Successive quantitative analysis may provide results that could help in treating sleep disorders closely associated with neuropsychiatric disorders.

DOI： 10.1038/s41398-023-02679-w

Orexinergic neurons contribute to autonomic cardiovascular regulation for locomotor exercise Open Access

Narai, E; Yoshimura, Y; Honaga, T; Mizoguchi, H; Yamanaka, A; Hiyama, TY; Watanabe, T; Koba, S

JOURNAL OF PHYSIOLOGY-LONDON 2024.2

Language：English Publisher：Journal of Physiology

Abstract: While the hypothalamic orexinergic nervous system is established as having a pivotal role in the long-term regulation of various organismic functions, including wakefulness, metabolism and hypertensive states, whether this system contributes to the rapid autonomic cardiovascular regulation during physical activity remains elusive. This study aimed to elucidate the role of the orexinergic nervous system in transmitting volitional motor signals, i.e. central command, to drive somatomotor and sympathetic cardiovascular responses. We first found that this system is activated by voluntary locomotor exercise as evidenced by an increased expression of Fos, a marker of neural activation, in the orexinergic neurons of Sprague–Dawley rats engaged in spontaneous wheel running. Next, using transgenic Orexin-Cre rats for optogenetic manipulation of orexinergic neurons, we found that optogenetic excitation of orexinergic neurons caused sympathoexcitation on a subsecond timescale under anaesthesia. In freely moving conscious rats, this excitatory stimulation rapidly elicited exploration-like behaviours, predominantly locomotor activity, along with pressor and tachycardiac responses. Meanwhile, optogenetic inhibition of orexinergic neurons during spontaneous wheel running immediately suppressed locomotor activities and blood pressure elevation without affecting basal cardiovascular homeostasis. Taken together, these findings demonstrate the essential role of the orexinergic nervous system in the central circuitry that transmits central command signals for locomotor exercise. This study not only offers insights into the brain circuit mechanisms precisely regulating autonomic cardiovascular systems during voluntary exercise but also likely contributes to our understanding of brain mechanisms underlying abnormal cardiovascular adjustments to exercise in pathological conditions, such as hypertension. (Figure presented.). Key points: The hypothalamic orexinergic nervous system plays various roles in the long-term regulation of autonomic and endocrine functions, as well as motivated behaviours. We present a novel, rapid role of the orexinergic nervous system, revealing its significance as a crucial substrate in the brain circuit mechanisms that coordinate somatomotor and autonomic cardiovascular controls for locomotor exercise. Our data demonstrate that orexinergic neurons relay volitional motor signals, playing a necessary and sufficient role in the autonomic cardiovascular regulation required for locomotor exercise in rats. The findings contribute to our understanding of how the brain precisely regulates autonomic cardiovascular systems during voluntary exercise, providing insights into the central neural mechanisms that enhance physical performance moment-by-moment during exercise.

DOI： 10.1113/JP285791

Rho kinase inhibitors ameliorate cognitive impairment in a male mouse model of methamphetamine-induced schizophrenia Open Access

Liao, JZ; Dong, GY; Zhu, WJ; Wulaer, B; Mizoguchi, H; Sawahata, M; Liu, Y; Kaibuchi, K; Ozaki, N; Nabeshima, T; Nagai, T; Yamada, K

PHARMACOLOGICAL RESEARCH Vol. 194 page： 106838 2023.8

Language：English Publisher：Pharmacological Research

Schizophrenia (SCZ) is a severe psychiatric disorder characterized by positive symptoms, negative symptoms, and cognitive deficits. Current antipsychotic treatment in SCZ improves positive symptoms but has major side effects and little impact on negative symptoms and cognitive impairment. The pathoetiology of SCZ remains unclear, but is known to involve small GTPase signaling. Rho kinase, an effector of small GTPase Rho, is highly expressed in the brain and plays a major role in neurite elongation and neuronal architecture. This study used a touchscreen-based visual discrimination (VD) task to investigate the effects of Rho kinase inhibitors on cognitive impairment in a methamphetamine (METH)–treated male mouse model of SCZ. Systemic injection of the Rho kinase inhibitor fasudil dose-dependently ameliorated METH-induced VD impairment. Fasudil also significantly suppressed the increase in the number of c-Fos–positive cells in the infralimbic medial prefrontal cortex (infralimbic mPFC) and dorsomedial striatum (DMS) following METH treatment. Bilateral microinjections of Y-27632, another Rho kinase inhibitor, into the infralimbic mPFC or DMS significantly ameliorated METH-induced VD impairment. Two proteins downstream of Rho kinase, myosin phosphatase-targeting subunit 1 (MYPT1; Thr696) and myosin light chain kinase 2 (MLC2; Thr18/Ser19), exhibited increased phosphorylation in the infralimbic mPFC and DMS, respectively, after METH treatment, and fasudil inhibited these increases. Oral administration of haloperidol and fasudil ameliorated METH-induced VD impairment, while clozapine had little effect. Oral administration of haloperidol and clozapine suppressed METH-induced hyperactivity, but fasudil had no effect. These results suggest that METH activates Rho kinase in the infralimbic mPFC and DMS, which leads to cognitive impairment in male mice. Rho kinase inhibitors ameliorate METH-induced cognitive impairment, perhaps via the cortico-striatal circuit.

DOI： 10.1016/j.phrs.2023.106838

Fasudil ameliorates methamphetamine-induced cognitive dysfunction in mice carrying schizophrenia-associated gene mutations in the Arhgap10 gene

Tanaka, R; Liao, JZ; Mori, D; Nagai, T; Matsuzaki, T; Nabeshima, T; Kaibuchi, K; Ozaki, N; Mizoguchi, H; Yamada, K

BRITISH JOURNAL OF PHARMACOLOGY Vol. 180 page： 1004 - 1004 2023.7

Retrospective Analysis of Neutrophil-to-Lymphocyte Ratio in Patients with Melanoma Who Received Ipilimumab Monotherapy or Ipilimumab in Combination with Nivolumab in Japan Open Access

Matsumura Yuka, Kawarada Yuki, Matsuo Momo, Yokota Kenji, Mizoguchi Hiroyuki, Akiyama Masashi, Yamada Kiyofumi

Biological and Pharmaceutical Bulletin Vol. 46 ( 3 ) page： 427 - 431 2023.3

Language：English Publisher：The Pharmaceutical Society of Japan

Studies have reported an association between elevated neutrophil-to-lymphocyte ratio (NLR) and poor prognosis in patients with melanoma treated with ipilimumab. However, it remains unclear whether NLR is useful in Japanese patients with melanoma, and if so, what is the optimal cut-off value. We retrospectively examined 38 patients who received ipilimumab from August 2015 to November 2021 at Nagoya University Hospital. We divided patients into two groups: 1–2 versus 3–4 cycles of ipilimumab. In univariate analysis, baseline neutrophil count and NLR were significantly higher in patients who discontinued ipilimumab within 2 cycles. With receiver operating characteristic analysis, the optimal NLR cut-off value was found to be 3.4 (area under the curve, 0.75; 95% confidence interval, 0.58–0.92). In multivariate logistic regression analysis, baseline NLR >3.4 was an independent risk factor for ipilimumab discontinuation (odds ratio, 15.6; 95% confidence interval, 3.0–82) that was significantly associated with shorter progression-free survival (PFS) (p = 0.003, log-rank test). In conclusion, NLR >3.4 is useful for selecting Japanese patients with melanoma who might have better PFS with ipilimumab-containing treatment. Because the optimal NLR cut-off value in this study was lower than values in American and European studies, it possibly differs by race. Hence, it should be extrapolated to Japanese patients with caution.

DOI： 10.1248/bpb.b22-00750

Inhibition of Rho-kinase ameliorates decreased spine density in the medial prefrontal cortex and methamphetamine-induced cognitive dysfunction in mice carrying schizophrenia-associated mutations of the Arhgap10 gene Reviewed Open Access

Tanaka, R; Liao, JZ; Hada, K; Mori, D; Nagai, T; Matsuzaki, T; Nabeshima, T; Kaibuchi, K; Ozaki, N; Mizoguchi, H; Yamada, K

PHARMACOLOGICAL RESEARCH Vol. 187 page： 106589 2023.1

Language：English Publisher：Pharmacological Research

Copy-number variations in the ARHGAP10 gene encoding Rho GTPase–activating protein 10 are associated with schizophrenia. Model mice (Arhgap10 S490P/NHEJ mice) that carry “double-hit” mutations in the Arhgap10 gene mimic the schizophrenia in a Japanese patient, exhibiting altered spine density, methamphetamine-induced cognitive dysfunction, and activation of RhoA/Rho-kinase signaling. However, it remains unclear whether the activation of RhoA/Rho-kinase signaling due to schizophrenia-associated Arhgap10 mutations causes the phenotypes of these model mice. Here, we investigated the effects of fasudil, a brain permeable Rho-kinase inhibitor, on altered spine density in the medial prefrontal cortex (mPFC) and on methamphetamine-induced cognitive impairment in a touchscreen‑based visual discrimination task in Arhgap10 S490P/NHEJ mice. Fasudil (20 mg/kg, intraperitoneal) suppressed the increased phosphorylation of myosin phosphatase–targeting subunit 1, a substrate of Rho-kinase, in the striatum and mPFC of Arhgap10 S490P/NHEJ mice. In addition, daily oral administration of fasudil (20 mg/kg/day) for 7 days ameliorated the reduced spine density of layer 2/3 pyramidal neurons in the mPFC. Moreover, fasudil (3–20 mg/kg, intraperitoneal) rescued the methamphetamine (0.3 mg/kg)-induced cognitive impairment of visual discrimination in Arhgap10 S490P/NHEJ mice. Our results suggest that Rho-kinase plays significant roles in the neuropathological changes in spine morphology and in the vulnerability of cognition to methamphetamine in mice with schizophrenia-associated Arhgap10 mutations.

DOI： 10.1016/j.phrs.2022.106589

Abnormal behavior and glial responses in an animal model of tau pathology

Liu Yue, Mizoguchi Hiroyuki, Sobue Akira, Shara Naruhiko, Yamanaka Koji, Yamada Kiyofumi

Proceedings for Annual Meeting of The Japanese Pharmacological Society Vol. 97 ( 0 ) page： 2-B-P-037 2023

Language：Japanese Publisher：Japanese Pharmacological Society

Tau hyperphosphorylation has been considered a major contributor to neurodegeneration in Alzheimer’s disease and related tauopathies and has gained prominence in the development of therapies for Alzheimer’s disease. Neuroinflammation plays an important role in the progression of neurodegenerative disorders, and activated astrocytes and microglia strongly influence Aβ and tau pathologies. Numerous transgenic mouse models that recapitulate critical Alzheimer’s disease-like pathology have been developed to examine the pathogenic mechanisms underlying Alzheimer’s disease and evaluate therapeutic approaches targeting tau, but the relevant mechanisms remain unknown. In this study, we investigated changes in gene expression related to neuroinflammation in glial cells of rTg4510 mice, an animal model of non-Alzheimer’s disease tauopathy. First, we analyzed 4- and 6-month-old rTg4510 mice in terms of cognition and behaviors that mimic the behavioral and psychological problems of dementia. Deterioration of executive functions and impairment of daily life activities are early signs of Alzheimer’s disease. In the present study, nest-building behavior, which represents active interaction with the environment, evaluated the executive functions that are the basis of daily life activities. Both 4- and 6-month-old rTg4510 mice displayed significantly impaired nesting behavior compared with control mice. Moreover, rTg4510 mice of both age groups exhibited abnormal exploratory behavior, and these mice spent a greater amount of time in the open arm of the plus-maze test than control mice. We also used magnetic-activated cell sorting to analyze the expressions of genes related to neuroinflammation, phagocytosis, and amyloid synthesis in the prefrontal cortex of rTg4510 mice. Axl, Cd11c, and CD68 expression levels were increased in microglial cells, and H2-D1, Psmb8, and H2-T23 expression levels in astrocytes were also increased in 6-month-old rTg4510 mice compared with control mice. In conclusion, neuroinflammation may be related to neuronal degeneration and abnormal behavior in rTg4510 mice.

DOI： 10.1254/jpssuppl.97.0_2-b-p-037

Nanobody-based RFP-dependent Cre recombinase for selective anterograde tracing in RFP-expressing transgenic animals Reviewed Open Access

Inutsuka, A; Maejima, S; Mizoguchi, H; Kaneko, R; Nomura, R; Takanami, K; Sakamoto, H; Onaka, T

COMMUNICATIONS BIOLOGY Vol. 5 ( 1 ) page： 979 2022.9

Language：English Publisher：Communications Biology

Transgenic animals expressing fluorescent proteins are widely used to label specific cells and proteins. By using a split Cre recombinase fused with mCherry-binding nanobodies or designed ankyrin repeat proteins, we created Cre recombinase dependent on red fluorescent protein (RFP) (Cre-DOR). Functional binding units for monomeric RFPs are different from those for polymeric RFPs. We confirmed selective target RFP-dependent gene expression in the mouse cerebral cortex using stereotaxic injection of adeno-associated virus vectors. In estrogen receptor-beta (Esr2)-mRFP1 mice and gastrin-releasing peptide receptor (Grpr)-mRFP1 rats, we confirmed that Cre-DOR can be used for selective tracing of the neural projection from RFP-expressing specific neurons. Cellular localization of RFPs affects recombination efficiency of Cre-DOR, and light and chemical-induced nuclear translocation of an RFP-fused protein can modulate Cre-DOR efficiency. Our results provide a method for manipulating gene expression in specific cells expressing RFPs and expand the repertory of nanobody-based genetic tools.

DOI： 10.1038/s42003-022-03944-2

Antipsychotic-like effects of fasudil, a Rho-kinase inhibitor, in a pharmacologic animal model of schizophrenia Reviewed Open Access

Takase, S; Liao, JZ; Liu, Y; Tanaka, R; Miyagawa, Y; Sawahata, M; Sobue, A; Mizoguchi, H; Nagai, T; Kaibuchi, K; Ozaki, N; Yamada, K

EUROPEAN JOURNAL OF PHARMACOLOGY Vol. 931 page： 175207 2022.9

Language：English Publisher：European Journal of Pharmacology

Current antipsychotics used to treat schizophrenia have associated problems, including serious side effects and treatment resistance. We recently identified a significant association of schizophrenia with exonic copy number variations in the Rho GTPase activating protein 10 (ARHGAP10) gene using genome-wide analysis. ARHGAP10 encodes a RhoGAP superfamily member that is involved in small GTPase signaling. In mice, Arhgap10 gene variations result in RhoA/Rho-kinase pathway activation. We evaluated the pharmacokinetics of fasudil and hydroxyfasudil using liquid chromatography-tandem mass spectrometry in mice. The antipsychotic effects of fasudil on hyperlocomotion, social interaction deficits, prepulse inhibition deficits, and novel object recognition deficits were also investigated in a MK-801-treated pharmacological mouse schizophrenia model. Fasudil and its major metabolite, hydroxyfasudil, were detected in the brain at concentrations above their respective Ki values for Rho-kinase after intraperitoneal injection of 10 mg kg−1 fasudil. Fasudil improved the hyperlocomotion, social interaction deficits, prepulse inhibition deficits, and novel object recognition deficits in MK-801-treated mice in a dose-dependent manner. Following oral administration of fasudil, brain hydroxyfasudil was detected at concentration above the Ki value for Rho-kinase whilst fasudil was undetectable. MK-801-induced hyperlocomotion was also improved by oral fasudil administration. These results suggest that fasudil has antipsychotic-like effects on the MK-801-treated pharmacological mouse schizophrenia model. There are two isoforms in Rho-kinase, and further investigation is needed to clarify the isoforms involved in the antipsychotic-like effects of fasudil in the MK-801-treated mouse schizophrenia model.

DOI： 10.1016/j.ejphar.2022.175207

Mice with exonic RELN deletion identified from a patient with schizophrenia have impaired visual discrimination learning and reversal learning in touchscreen operant tasks Reviewed

A machine learning model that emulates experts' decision making in vancomycin initial dose planning Reviewed Open Access

Matsuzaki, T; Kato, Y; Mizoguchi, H; Yamada, K

JOURNAL OF PHARMACOLOGICAL SCIENCES Vol. 148 ( 4 ) page： 358 - 363 2022.4

Language：English Publishing type：Research paper (scientific journal) Publisher：Journal of Pharmacological Sciences

Vancomycin is a glycopeptide antibiotic that is a primary treatment for methicillin-resistant Staphylococcus aureus infections. To enhance its clinical effectiveness and prevent nephrotoxicity, therapeutic drug monitoring (TDM) of trough concentrations is recommended. Initial vancomycin dosing regimens are determined based on patient characteristics such as age, body weight, and renal function, and dosing strategies to achieve therapeutic concentration windows at initial TDM have been extensively studied. Although numerous dosing nomograms for specific populations have been developed, no comprehensive strategy exists for individually tailoring initial dosing regimens; therefore, decision making regarding initial dosing largely depends on each clinician's experience and expertise. In this study, we applied a machine-learning (ML) approach to integrate clinician knowledge into a predictive model for initial vancomycin dosing. A dataset of vancomycin initial dose plans defined by pharmacists experienced in vancomycin TDM (i.e., experts) was used to build the ML model. Although small training sets were used, we established a predictive model with a target attainment rate comparable to those of experts, another ML model, and commonly used vancomycin dosing software. Our strategy will help develop an expert-like predictive model that aids in decision making for initial vancomycin dosing, particularly in settings where dose planning consultations are unavailable.

DOI： 10.1016/j.jphs.2022.02.005

New Strategies for the Treatment of Neuropsychiatric Disorders Based on Reelin Dysfunction Reviewed Open Access

Tsuneura, Y; Nakai, T; Mizoguchi, H; Yamada, K

INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol. 23 ( 3 ) 2022.2

Language：English Publishing type：Research paper (scientific journal) Publisher：International Journal of Molecular Sciences

Reelin is an extracellular matrix protein that is mainly produced in Cajal-Retzius cells and controls neuronal migration, which is important for the proper formation of cortical layers in the developmental stage of the brain. In the adult brain, Reelin plays a crucial role in the regulation of N-methyl-D-aspartate receptor-dependent synaptic function, and its expression decreases postnatally. Clinical studies showed reductions in Reelin protein and mRNA expression levels in patients with psychiatric disorders; however, the causal relationship remains unclear. Reelin-deficient mice exhibit an abnormal neuronal morphology and behavior, while Reelin supplementation ameliorates learning deficits, synaptic dysfunctions, and spine loss in animal models with Reelin deficiency. These findings suggest that the neuronal deficits and brain dysfunctions associated with the down-regulated expression of Reelin are attenuated by enhancements in its expression and functions in the brain. In this review, we summarize findings on the role of Reelin in neuropsychiatric disorders and discuss potential therapeutic approaches for neuropsychiatric disorders associated with Reelin dysfunctions.

DOI： 10.3390/ijms23031829

Liao, JZ; Dong, GY; Wulaer, B; Sawahata, M; Mizoguchi, H; Mori, D; Ozaki, N; Nabeshima, T; Nagai, T; Yamada, K

BEHAVIOURAL BRAIN RESEARCH Vol. 416 page： 113569 2022.1

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

The Reelin gene (RELN) encodes a large extracellular protein, which has multiple roles in brain development and adult brain function. It activates a series of neuronal signal transduction pathways in the adult brain that function in synaptic plasticity, dendritic morphology, and cognitive function. To further investigate the roles of Reln in brain function, we generated a mouse line using the C57BL/6 J strain with the specific Reln deletion identified from a Japanese patient with schizophrenia (Reln-del mice). These mice exhibited abnormal sociality, but the pathophysiological significance of the Reln deletion for higher brain functions, such as learning and behavioral flexibility remains unclear. In this study, cognitive function in Reln-del mice was assessed using touchscreen-based visual discrimination (VD) and reversal learning (RL) tasks. Reln-del mice showed normal learning in the simple VD task, but the learning was delayed in the complex VD task as compared to their wild-type (WT) littermates. In the RL task, sessions were divided into early perseverative phase (sessions with <50% correct) and later learning phase (sessions with ≥50% correct). Reln-del mice showed normal perseveration but impaired relearning ability in both simple RL and complex RL task as compared to WT mice. These results suggest that Reln-del mice have impaired learning ability, but the behavioral flexibility is unaffected. Overall, the observed behavioral abnormalities in Reln-del mice suggest that this mouse model is a useful preclinical tool for investigating the neurobiological mechanism underlying cognitive impairments in schizophrenia and a therapeutic strategy.

DOI： 10.1016/j.bbr.2021.113569

Dynamic changes in orexin activities associated with reward-based motivative behavior

Yutao Dong, Mizoguchi Hiroyuki, Yamanaka Akihiro, Yamada Kiyofumi

Proceedings for Annual Meeting of The Japanese Pharmacological Society Vol. 95 ( 0 ) page： 1-SS-08 2022

Language：Japanese Publisher：Japanese Pharmacological Society

Orexin neurons in the hypothalamus regulate physiological functions, including energy homeostasis and wakefulness, and are also related to motivation. Here, we examined the roles of orexin neurons in motivated behaviors. We measured the activities of orexin neurons using fiber photometry under a free-moving condition, in which the rats were subjected to the fixed ratio (FR) or progressive ratio (PR) schedule of a touchscreen-based automated operant task. To measure the activities of orexin neurons, AAV-FLEX-GCaMP7s was injected into the hypothalamus of Orexin-Cre rats. We found that under FR5 conditions in which rats were able to obtain a food pellet by touching the screen consecutively five times, the activity in orexin neurons was increased after the fifth screen touch (after which one food pellet is delivered). The activity peaked before rats obtained reward, and then decreased after food intake. Next, we included non-reward trials in the FR5 test in which the rat was not able to earn reward even after touching the screen five times. The orexin activities in non-reward trials were also increased after the fifth screen touch, but the decrease after food intake was diminished compared to those in reward-trials. In the PR schedule test, the orexin activities were gradually increased. Together, these observations suggest that the orexin activities are associated with motivational behaviors, and that orexin neurons may be involved in craving and reward prediction, and satisfaction.

DOI： 10.1254/jpssuppl.95.0_1-ss-08

Changes in the expression of interferon-induced transmembrane protein-3 (IFITM3) in the brains of Alzheimer‘s disease model mice

Liu Yue, Mizoguchi Hiroyuki, Sobue Akira, Yamanaka Koji, Yamada Kiyofumi

Proceedings for Annual Meeting of The Japanese Pharmacological Society Vol. 96 ( 0 ) page： 1-B-P-333 2022

Language：Japanese Publisher：Japanese Pharmacological Society

Interferon-induced transmembrane protein-3 (IFITM3) belongs to the IFITM family, which comprises five and seven subtypes in humans and mice, respectively. IFITM proteins participate in various biological processes such as the immune response, including suppression of viral infection. While the immune response is associated with the pathology and development of Alzheimer's disease (AD), it is unknown whether this response is beneficial or harmful. Recently, IFITM3 was found to be a γ-secretase modulatory protein, a type of protein associated with the generation of amyloid b (Aβ). However, further research is needed to determine whether IFITM3 is associated with abnormal behaviors, including cognitive impairment in AD, and whether it may be a new molecular target for AD therapy. Since our final goal is to clarify the role of IFITM3 in an animal model of AD, in this study we used App-KI mice, which overproduce Aβ-42 without overexpressing amyloid precursor protein, to examine changes in IFITM3 expression. The cortex, dentate gyrus (DG), and CA3 regions of 4- and 8-month-old App-KI mice exhibited Aβ accumulation and also increased IFITM3 expression. Expressions of astrocytes and microglia were age-dependently increased around Aβ plaques. Notably, IFITM3 expression colocalized with astrocytes, which were situated near Aβ in all brain regions of 8-month-old App-KI mice. These results suggest that IFITM3 is increased in astrocytes and is accompanied by Aβ accumulation.

DOI： 10.1254/jpssuppl.96.0_1-b-p-333

Alzheimer's Disease Animal Models: Elucidation of Biomarkers and Therapeutic Approaches for Cognitive Impairment Reviewed Open Access

Nakai, T; Yamada, K; Mizoguchi, H

INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol. 22 ( 11 ) 2021.6

Language：English Publishing type：Research paper (scientific journal) Publisher：International Journal of Molecular Sciences

Alzheimer’s disease (AD) is an age-related and progressive neurodegenerative disorder. It is widely accepted that AD is mainly caused by the accumulation of extracellular amyloid β (Aβ) and intracellular neurofibrillary tau tangles. Aβ begins to accumulate years before the onset of cognitive impairment, suggesting that the benefit of currently available interventions would be greater if they were initiated in the early phases of AD. To understand the mechanisms of AD pathogenesis, various transgenic mouse models with an accelerated accumulation of Aβ and tau tangles have been developed. However, none of these models exhibit all pathologies present in human AD. To overcome these undesirable phenotypes, APP knock-in mice, which were presented with touchscreen-based tasks, were developed to better evaluate the efficacy of candidate therapeutics in mouse models of early-stage AD. This review assesses several AD mouse models from the aspect of biomarkers and cognitive impairment and discusses their potential as tools to provide novel AD therapeutic approaches.

DOI： 10.3390/ijms22115549

Analysis of Reelin signaling and neurodevelopmental trajectory in primary cultured cortical neurons with RELN deletion identified in schizophrenia Reviewed Open Access

Tsuneura, Y; Sawahata, M; Itoh, N; Miyajima, R; Mori, D; Kohno, T; Hattori, M; Sobue, A; Nagai, T; Mizoguchi, H; Nabeshima, T; Ozaki, N; Yamada, K

NEUROCHEMISTRY INTERNATIONAL Vol. 144 page： 104954 2021.3

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

Reelin, an extracellular matrix protein, is secreted by Cajal-Retzius cells and plays crucial roles in the development of brain structures and neuronal functions. Reductions in Reelin cause the brain dysfunctions associated with mental disorders, such as schizophrenia. A recent genome-wide copy number variation analysis of Japanese schizophrenia patients identified a novel deletion in RELN encoding Reelin. To clarify the pathophysiological role of the RELN deletion, we developed transgenic mice carrying the RELN deletion (Reln-del) and found abnormalities in their brain structures and social behavior. In the present study, we performed an in vitro analysis of Reelin expression, intracellular Reelin signaling, and the morphology of primary cultured cortical neurons from wild-type (WT) and Reln-del mice. Reelin protein levels were lower in Reln-del neurons than in WT neurons. Dab1 expression levels were significantly higher in Reln-del neurons than in WT neurons, suggesting that Reelin signaling was decreased in Reln-del neurons. Reelin was mainly expressed in γ-aminobutyric acid (GABA)-ergic inhibitory neurons, but not in parvalbumin (PV)-positive neurons. A small proportion of Ca2+/calmodulin-dependent protein kinase II α subunit (CaMKIIα)-positive excitatory neurons also expressed Reelin. In comparisons with WT neurons, significant decreases were observed in neurite lengths and branch points as well as in the number of postsynaptic density protein 95 (PSD95) immunoreactive puncta in Reln-del neurons. A disintegrin and metalloproteinase with thrombospondin motifs-3 (ADAMTS-3) is a protease that inactivates Reelin by cleavage at the N-t site. The knockdown of ADAMTS-3 by short hairpin RNAs suppressed Reelin cleavage in conditioned medium and reduced Dab1 expression, indicating that Reelin signaling was enhanced in the primary cultured cortical neurons of WT and heterozygous Reln-del. Accordingly, the inhibition of ADAMTS-3 may be a potential candidate in the clinical treatment of schizophrenia by enhancing Reelin signaling in the brain.

DOI： 10.1016/j.neuint.2020.104954

REM sleep-active MCH neurons are involved in forgetting hippocampus-dependent memories Reviewed Open Access

Izawa, S; Chowdhury, S; Miyazaki, T; Mukai, Y; Ono, D; Inoue, R; Ohmura, Y; Mizoguchi, H; Kimura, K; Yoshioka, M; Terao, A; Kilduff, TS; Yamanaka, A

SCIENCE Vol. 365 ( 6459 ) page： 1308 - + 2019.9

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

The neural mechanisms underlying memory regulation during sleep are not yet fully understood.We found that melanin concentrating hormone-producing neurons (MCH neurons) in the hypothalamus actively contribute to forgetting in rapid eye movement (REM) sleep. Hypothalamic MCH neurons densely innervated the dorsal hippocampus. Activation or inhibition of MCH neurons impaired or improved hippocampus-dependent memory, respectively. Activation of MCH nerve terminals in vitro reduced firing of hippocampal pyramidal neurons by increasing inhibitory inputs.Wake- and REM sleep- active MCH neurons were distinct populations that were randomly distributed in the hypothalamus. REM sleep state-dependent inhibition of MCH neurons impaired hippocampus-dependent memory without affecting sleep architecture or quality. REM sleep-active MCH neurons in the hypothalamus are thus involved in active forgetting in the hippocampus.

DOI： 10.1126/science.aax9238

Maternal separation as a risk factor for aggravation of neuropathic pain in later life in mice

Preproenkephalin-expressing ventral pallidal neurons control inhibitory avoidance learning Reviewed Open Access

Macpherson, T; Mizoguchi, H; Yamanaka, A; Hikida, T

NEUROCHEMISTRY INTERNATIONAL Vol. 126 page： 11 - 18 2019.6

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

The ventral pallidum (VP) is a critical component of the basal ganglia neurocircuitry regulating learning and decision making; however, its precise role in controlling associative learning of environmental stimuli conditioned to appetitive or aversive outcomes is still unclear. Here, we investigated the expression of preproenkephalin, a polypeptide hormone previously shown to be expressed in nucleus accumbens neurons controlling aversive learning, within GABAergic and glutamatergic VP neurons. Next, we explored the behavioral consequences of chemicogenetic inhibition or excitation of preproenkephalin-expressing VP neurons on associative learning of reward- or aversion-paired stimuli in autoshaping and inhibitory avoidance tasks, respectively. We reveal for the first time that preproenkephalin is expressed predominantly in GABAergic rather than glutamatergic VP neurons, and that excitation of these preproenkephalin-expressing VP neurons was sufficient to impair inhibitory avoidance learning. These findings indicate the necessity for inhibition of preproenkephalin-expressing VP neurons for avoidance learning, and suggest these neurons as a potential therapeutic target for psychiatric disorders associated with maladaptive aversive learning.

DOI： 10.1016/j.neuint.2019.02.011

Hiroyuki Mizoguchi, Kazuya Fukumoto, Gaku Sakamoto, Shijie Jin, Asako Toyama, Tian Wang, Akio Suzumura, Jun Sato

Behavioural Brain Research Vol. 359 page： 942 - 949 2019.2

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

Psychological stresses such as social loss and separation during childhood induce hardship, referred to as emotional pain. These experiences are well-documented risk factors for the development of physical pain in adulthood. However, the underlying neuronal mechanisms of this exacerbation of pain are largely unknown, and consequently there is no effective pharmacotherapy. In this study, we sought to determine whether infant maternal separation (MS) contributes to aggravation of neuropathic pain in adult mice. MS increased anxiety- and depression-like behavioral responses to adult stress. In MS animals, chronic constriction injury (CCI) heightened the sensory dimension of chronic pain relative to that of control mice. However, MS mice treated with fluoxetine for 4 weeks after MS did not exhibit augmentation of allodynia, and their emotional response was attenuated. Microglia were more abundant in the spinal cord in MS/CCI mice than in control/CCI mice. These results suggest that emotional impairment is related to augmentation of neuropathic pain, and that dysfunction of microglial activation contributes to heightened pain sensitivity.

DOI： 10.1016/j.bbr.2018.06.015

Nicotine and varenicline ameliorate changes in reward-based choice strategy and altered decision-making in methamphetamine-treated rats

Hiroyuki Mizoguchi, Tian Wang, Mizuki Kusaba, Kazuya Fukumoto, Kiyofumi Yamada

Behavioural Brain Research Vol. 359 page： 935 - 941 2019.2

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

Patients suffering from neuropsychiatric disorders such as substance use and addiction disorders show impaired decision-making, which may be associated with their psychiatric disorders. Previously, using a gambling test for rodents, we demonstrated that methamphetamine-dependent rats showed alterations in their decision-making strategy. In this study, we investigated the effect of nicotine on impaired decision-making strategy in rats which have been treated repeatedly with methamphetamine. Nicotine has previously been shown to have therapeutic effects on attentional and cognitive abnormalities in psychosis. Rats were administered methamphetamine subcutaneously (sc) at 4 mg/kg once a day, for 30 days, and their decision-making was then assessed with a rodent gambling task. We found that methamphetamine-treated rats preferred the high-risk/high-return actions, which is consistent with our previous findings. Methamphetamine-induced impairment of decision-making was reversed by daily nicotine treatment (0.3 mg/kg, sc). This effect was associated with the reduction of lose-shift behavior after negative reward prediction error. Repeated treatment with nicotine had no effects on arm-choice behavior in naïve rats. Varenicline, an α4β2-nicotinic acetylcholine receptor partial agonist, also ameliorated the altered decision-making in methamphetamine-treated rats. Our findings suggest that nicotine treatment is useful for ameliorating the altered decision-making caused by methamphetamine treatment, and that the α4β2-nicotinic acetylcholine receptor is a therapeutic target for poor decision-making.

DOI： 10.1016/j.bbr.2018.06.016

Physiological centers of decision-making: manipulation of neural activity in insular cortex by AAV Open Access

Mizoguchi Hiroyuki, Yamada Kiyofumi

Folia Pharmacologica Japonica Vol. 153 ( 5 ) page： 224 - 230 2019

Language：Japanese Publisher：The Japanese Pharmacological Society

Decision-making is a key activity process that influences many aspects of daily living and both mental and physical health. In general, healthy participants reveal rational choice, but patients with neuropsychiatric disorders reveal irrational and risky choice in decision-making. Addiction is one of typical diseases revealed risky decision-making, addicts select risky action and options that confer short-term rewards at the cost of long-term disadvantages. Thus, irrational and risky decision-making is recognized as a core problem in patients with neuropsychiatric disorders, and a better understanding of the mechanisms underlying altered decision-making would provide insights into potential therapeutic approaches for these diseases. However, the neural pathway and substrates underlying these deficits are particularly unknown. Recently, we found that insular cortex is one of key regions for risky decision-making in an animal model of methamphetamine addiction, by using the designer receptor exclusively activated by designer drug (DREADD) technology, and that GABAergic dysfunction in insular cortex is involved in evaluating the subjective value of reward and reward prediction error. These brain dysfunctions would be related to risk taking behavior in addiction. In this review, we introduced the possible neural pathway related to risky decision-making and behavioral changes in choice strategy using adeno associated virus (AAV).

DOI： 10.1254/fpj.153.224

Optimization of operant test for testing risky decision-making in mice

Mizoguchi Hiroyuki, Wang Tian, Saifullah Md. Ali Bin, Fukumoto Kazuya, Yamada Kiyofumi

Proceedings for Annual Meeting of The Japanese Pharmacological Society Vol. 92 ( 0 ) page： 1-P-023 - P-023 2019

Language：Japanese Publisher：Japanese Pharmacological Society

Decision making in complex and uncertain situations is a fundamental adaptive process resulting from the integration of several executive functions. Impaired decision-making is a symptomatic feature of a number of psychiatric disorders. In general, patients with psychiatric disorders show a propensity to prefer actions associated with large short-term gains but long-term losses preferentially to those associated with small but long-term gains. They are more likely to select risky options and show an altered temporal horizon of risks and benefits. Moreover, clinical studies report that dopamine therapy induce impaired decision-making in patients with dopaminergic dysfunction such as Parkinson's disease and Redox-less syndrome. Thus, to establish and optimize the animal model of impaired decision-making is important for development of new therapeutic strategy in these disorders.To clarify the underlying neurobiology of decision-making, we conducted a study in healthy mice by using a mouse gambling operant test based on uncertainty and conflicting choices. Mice chose the low-risk / low-reward option on the reward amount- and provability-dependent manner. Our findings suggest that healthy mice prefer risk-aversive choice in this operant test as dose man in Iowa gambling test.

DOI： 10.1254/jpssuppl.92.0_1-p-023

Behavioral characterization of APP knock-in mice model in touchscreen-based tests aiming early detection of Alzheimer's disease.

Saifullah MD. Ali Bin, Komine Okiru, Sobue Akira, Yamanaka Koji, Mizoguchi Hiroyuki

Proceedings for Annual Meeting of The Japanese Pharmacological Society Vol. 92 ( 0 ) page： 1-P-041 - P-041 2019

Language：Japanese Publisher：Japanese Pharmacological Society

Alzheimer's disease (AD) is a progressive disease characterized by loss of memory and other important mental functions. Accumulation of amyloid beta (Aβ) and fibrillary tangles are the main pathological hallmarks of this disease. Emerging data suggest that the disease process begins years before clinical diagnostic confirmation; thus, methods to improve early detection would provide opportunities for early intervention to delay progressive cognitive decline and disease onset. In our research we assessed the cognitive abilities of APPNL-G-F/NL-G-F knock-in (APP-KI) mice with a touch screen-based automated test battery and water maze test. These tests are mainly dependent on the brain regions that are prone to Aβ accumulation at the earliest stages of the disease. We subjected male 6- and 11-months old APP-KI mice in water maze test where only older mice showed significantly worsened behavior than wild-type mice. However, using touchscreen based behavioral test it was possible to detect cognitive impairment in APP-KI mice at an early (4 months) stage while classical behavioral tests shows comparable results between wild-type and disease model mice.

DOI： 10.1254/jpssuppl.92.0_1-p-041

Basic researches to support the symbiotic society with dementia

Yanai Shuichi, Takase Kenkichi, Yamaguchi Tetsuo, Uchida Sae, Izuo Naotaka, Mizoguchi Hiroyuki, Inagaki Hiroki, Kusaka Nahoko

The Proceedings of the Annual Convention of the Japanese Psychological Association Vol. 82 ( 0 ) page： SS-029 - SS-029 2018.9

AN OPERANT TASK FOR TESTING RISKY DECISION-MAKING IN MICE

Wang T., Fukumoto K., Mizoguchi H., Yamada K.

ALCOHOLISM-CLINICAL AND EXPERIMENTAL RESEARCH Vol. 42 page： 48A - 48A 2018.8

ギャンブル障害の現状と薬剤師の役割 Reviewed

溝口博之

医薬ジャーナル Vol. 54(4) page： 1037 - 1040 2018

GAP junction/hemichannel blockers ameliorate the disease progression of FTLD/ALS mice

Takeuchi H, Mizoguchi H, Tanaka F, Suzumura A

JOURNAL OF THE NEUROLOGICAL SCIENCES Vol. 381 page： 714 - 715 2017.10

創薬標的としてのnAChR：精神疾患患者で喫煙率が高い理由！？

溝口博之

ファルマシア Vol. 53 ( 9 ) page： 923 - 923 2017

Language：Japanese Publisher：公益社団法人日本薬学会

前頭前皮質は高次の学習記憶を司る脳部位であり，ニコチン性アセチルコリン受容体(nAChR)を介したアセチルコリン神経の投射・支配を受けている．統合失調症などの精神疾患患者は，前頭前皮質の機能が低下(hypofrontality)しており，また，喫煙率が高い傾向がある．最近，ゲノムワイド関連解析により，nAChRのα5サブユニットを司るヒトCHRNA5遺伝子に一塩基多型(SNP)が存在することが分かり，この変異が喫煙や統合失調症のリスクを高める可能性が報告された．基礎研究においても，マウスのα5サブユニット遺伝子を欠損させると，前頭前皮質の形態学的変化や行動に異常が生じることが報告されているが，ヒト遺伝子多型が，細胞活性あるいは神経回路にどのような影響をもたらすのか，さらには統合失調症患者で観察されるような行動障害や，hypofrontalityを引き起こすかは不明である． 本稿では，ヒトα5サブユニット変異体(α5SNP)を発現するマウスを用いて，α5SNPがもたらす皮質機能障害について検討したKoukouliらの研究を紹介する． なお，本稿は下記の文献に基づいて，その研究成果を紹介するものである. 1) Tobacco and Genetics Consortium., Nat. Genet., 42, 441–447(2010). 2) Schizophrenia Working Group of the Psychiatric Genomics Consortium., Nature, 511, 421–427(2014). 3) Proulx E. et al., Cell. Mol. Life Sci., 71, 1225-1244(2014). 4) Koukouli F. et al., Nat. Med., 23, 347–354(2017).

DOI： 10.14894/faruawpsj.53.9_923

Hypothalamic peptidergic neurons regulates sleep/wakefulness and memory

Izawa, S; Inoue, R; Mukai, Y; Terao, A; Chowdhury, S; Mizoguchi, H; Yamanaka, A

JOURNAL OF SLEEP RESEARCH Vol. 25 page： 115 - 116 2016.9

Disrupted axon-glia interactions at the paranode in myelinated nerves cause axonal degeneration and neuronal cell death in the aged Caspr mutant mouse shambling

Takagishi, Y; Katanosaka, K; Mizoguchi, H; Murata, Y

NEUROBIOLOGY OF AGING Vol. 43 page： 34 - 46 2016.7

Language：English Publisher：Neurobiology of Aging

Emerging evidence suggests that axonal degeneration is a disease mechanism in various neurodegenerative diseases and that the paranodes at the nodes of Ranvier may be the initial site of pathogenesis. We investigated the pathophysiology of the disease process in the central and peripheral nervous systems of a Caspr mutant mouse, shambling (shm), which is affected by disrupted paranodal structures and impaired nerve conduction of myelinated nerves. The shm mice manifest a progressive neurological phenotype as mice age. We found extensive axonal degeneration and a loss of neurons in the central nervous system and peripheral nervous system in aged shm mice. Axonal alteration of myelinated nerves was defined by abnormal distribution and expression of neurofilaments and derangements in the status of phosphorylated and non/de-phosphorylated neurofilaments. Autophagy-related structures were also accumulated in degenerated axons and neurons. In conclusion, our results suggest that disrupted axon-glia interactions at the paranode cause the cytoskeletal alteration in myelinated axons leading to neuronal cell death, and the process involves detrimental autophagy and aging as factors that promote the pathogenesis.

DOI： 10.1016/j.neurobiolaging.2016.03.020

Usefulness of DREADD technology combined with adeno-associated virus vector in behavioral pharmacology

Chronic Hyponatremia Causes Neurologic and Psychologic Impairments Reviewed

Fujisawa H, Sugimura Y, Takagi H, Mizoguchi H, Takeuchi H, Izumida H, Nakashima K, Ochiai H, Takeuchi S, Kiyota A, Fukumoto K, Iwama S, Takagishi Y, Hayashi Y, Arima H, Komatsu Y, Murata Y, Oiso Y

Journal of the American Society of Nephrology Vol. 27 ( 3 ) page： 766 - 80 2016.3

Mizoguchi, H; Yamanaka, A; Yamada, K

JOURNAL OF PHARMACOLOGICAL SCIENCES Vol. 130 ( 3 ) page： S73 - S73 2016.3

Insular neural system controls decision-making in healthy and methamphetamine-treated rats Reviewed

Hiroyuki Mizoguchi, Kentaro Katahira, Ayumu Inutsuka, Kazuya Fukumoto, Akihiro Nakamura, Tian Wang, Taku Nagai, Jun Sato, Makoto Sawada, Hideki Ohira, Akihiro Yamanaka, Kiyofumi Yamada

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Vol. 112 ( 29 ) page： E3930 - 9 2015.7

Language：English Publishing type：Research paper (scientific journal) Publisher：NATL ACAD SCIENCES

Patients suffering from neuropsychiatric disorders such as substance-related and addictive disorders exhibit altered decision-making patterns, which may be associated with their behavioral abnormalities. However, the neuronal mechanisms underlying such impairments are largely unknown. Using a gambling test, we demonstrated that methamphetamine (METH)-treated rats chose a high-risk/high-reward option more frequently and assigned higher value to high returns than control rats, suggestive of changes in decision-making choice strategy. Immunohistochemical analysis following the gambling test revealed aberrant activation of the insular cortex (INS) and nucleus accumbens in METH-treated animals. Pharmacological studies, together with in vivo microdialysis, showed that the insular neural system played a crucial role in decision-making. Moreover, manipulation of INS activation using designer receptor exclusively activated by designer drug technology resulted in alterations to decision-making. Our findings suggest that the INS is a critical region involved in decision-making and that insular neural dysfunction results in risk-taking behaviors associated with altered decision-making.

DOI： 10.1073/pnas.1418014112

The insular neural system controls decision-making in healthy and drug-dependent rats

Mizoguchi, H; Yamada, K

JOURNAL OF PHARMACOLOGICAL SCIENCES Vol. 128 ( 3 ) page： S61 - S61 2015.7

Mice carrying a schizophrenia-associated mutation of the Arhgap10 gene are vulnerable to the effects of methamphetamine treatment on cognitive function: association with morphological abnormalities in striatal neurons. Reviewed International journal Open Access

Kazuhiro Hada, Bolati Wulaer, Taku Nagai, Norimichi Itoh, Masahito Sawahata, Akira Sobue, Hiroyuki Mizoguchi, Daisuke Mori, Itaru Kushima, Toshitaka Nabeshima, Norio Ozaki, Kiyofumi Yamada

Molecular brain Vol. 14 ( 1 ) page： 21 - 21 2021.1

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

We recently found a significant association between exonic copy-number variations in the Rho GTPase activating protein 10 (Arhgap10) gene and schizophrenia in Japanese patients. Special attention was paid to one patient carrying a missense variant (p.S490P) in exon 17, which overlapped with an exonic deletion in the other allele. Accordingly, we generated a mouse model (Arhgap10 S490P/NHEJ mice) carrying a missense variant and a coexisting frameshift mutation. We examined the spatiotemporal expression of Arhgap10 mRNA in the brain and found the highest expression levels in the cerebellum, striatum, and nucleus accumbens (NAc), followed by the frontal cortex in adolescent mice. The expression levels of phosphorylated myosin phosphatase-targeting subunit 1 and phosphorylated p21-activated kinases in the striatum and NAc were significantly increased in Arhgap10 S490P/NHEJ mice compared with wild-type littermates. Arhgap10 S490P/NHEJ mice exhibited a significant increase in neuronal complexity and spine density in the striatum and NAc. There was no difference in touchscreen-based visual discrimination learning between Arhgap10 S490P/NHEJ and wild-type mice, but a significant impairment of visual discrimination was evident in Arhgap10 S490P/NHEJ mice but not wild-type mice when they were treated with methamphetamine. The number of c-Fos-positive cells was significantly increased after methamphetamine treatment in the dorsomedial striatum and NAc core of Arhgap10 S490P/NHEJ mice. Taken together, these results suggested that schizophrenia-associated Arhgap10 gene mutations result in morphological abnormality of neurons in the striatum and NAc, which may be associated with vulnerability of cognition to methamphetamine treatment.

DOI： 10.1186/s13041-021-00735-4

Microglial gene signature reveals loss of homeostatic microglia associated with neurodegeneration of Alzheimer's disease. Reviewed International journal Open Access

Akira Sobue, Okiru Komine, Yuichiro Hara, Fumito Endo, Hiroyuki Mizoguchi, Seiji Watanabe, Shigeo Murayama, Takashi Saito, Takaomi C Saido, Naruhiko Sahara, Makoto Higuchi, Tomoo Ogi, Koji Yamanaka

Acta neuropathologica communications Vol. 9 ( 1 ) page： 1 - 1 2021.1

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

Microglia-mediated neuroinflammation has been implicated in the pathogenesis of Alzheimer's disease (AD). Although microglia in aging and neurodegenerative disease model mice show a loss of homeostatic phenotype and activation of disease-associated microglia (DAM), a correlation between those phenotypes and the degree of neuronal cell loss has not been clarified. In this study, we performed RNA sequencing of microglia isolated from three representative neurodegenerative mouse models, AppNL-G-F/NL-G-F with amyloid pathology, rTg4510 with tauopathy, and SOD1G93A with motor neuron disease by magnetic activated cell sorting. In parallel, gene expression patterns of the human precuneus with early Alzheimer's change (n = 11) and control brain (n = 14) were also analyzed by RNA sequencing. We found that a substantial reduction of homeostatic microglial genes in rTg4510 and SOD1G93A microglia, whereas DAM genes were uniformly upregulated in all mouse models. The reduction of homeostatic microglial genes was correlated with the degree of neuronal cell loss. In human precuneus with early AD pathology, reduced expression of genes related to microglia- and oligodendrocyte-specific markers was observed, although the expression of DAM genes was not upregulated. Our results implicate a loss of homeostatic microglial function in the progression of AD and other neurodegenerative diseases. Moreover, analyses of human precuneus also suggest loss of microglia and oligodendrocyte functions induced by early amyloid pathology in human.

DOI： 10.1186/s40478-020-01099-x

Analysis of Reelin signaling and neurodevelopmental trajectory in primary cultured cortical neurons with RELN deletion identified in schizophrenia. Invited Reviewed

Tsuneura Y, Sawahata M, Itoh N, Miyajima R, Mori D, Kohno T, Hattori M, Sobue A, Nagai T, Mizoguchi H, Nabeshima T, Ozaki N, Yamada K

Neurochemistry International. Vol. 144 page： 104954 2021.1

Touchscreen-based location discrimination and paired associate learning tasks detect cognitive impairment at an early stage in an App knock-in mouse model of Alzheimer's disease Reviewed Open Access

Saifullah, MAB; Komine, O; Dong, YT; Fukumoto, K; Sobue, A; Endo, F; Saito, T; Saido, TC; Yamanaka, K; Mizoguchi, H

MOLECULAR BRAIN Vol. 13 ( 1 ) page： 147 2020.11

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

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline with accumulation of amyloid beta (Aβ) and neurofibrillary tangles that usually begins 15–30 years before clinical diagnosis. Rodent models that recapitulate aggressive Aβ and/or the pathology of neurofibrillary tangles are essential for AD research. Accordingly, non-invasive early detection systems in these animal models are required to evaluate the phenotypic changes, elucidate the mechanism of disease progression, and facilitate development of novel therapeutic approaches. Although many behavioral tests efficiently reveal cognitive impairments at the later stage of the disease in AD models, it has been challenging to detect such impairments at the early stage. To address this issue, we subjected 4–6-month-old male AppNL−G−F/NL−G−F knock-in (App-KI) mice to touchscreen-based location discrimination (LD), different object–location paired-associate learning (dPAL), and reversal learning tests, and compared the results with those of the classical Morris water maze test. These tests are mainly dependent on the brain regions prone to Aβ accumulation at the earliest stages of the disease. At 4–6 months, considered to represent the early stage of disease when mice exhibit initial deposition of Aβ and slight gliosis, the classical Morris water maze test revealed no difference between groups, whereas touchscreen-based LD and dPAL tasks revealed significant impairments in task performance. Our report is the first to confirm that a systematic touchscreen-based behavioral test battery can sensitively detect the early stage of cognitive decline in an AD-linked App-KI mouse model. This system could be applied in future translational research.

DOI： 10.1186/s13041-020-00690-6

Methamphetamine use causes cognitive impairment and altered decision-making Reviewed

Mizoguchi, H; Yamada, K

NEUROCHEMISTRY INTERNATIONAL Vol. 124 page： 106 - 113 2019.3

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

Methamphetamine is a widely abused psychostimulant. It reverses transport through the dopamine transporter, thereby increasing the extracellular level of dopamine in the brain, which is associated with the rewarding effect. Repeated intake of methamphetamine leads to drug addiction, a chronically relapsing disorder characterized by compulsive drug taking, inability to limit intake, and intense drug cravings. The molecular and cellular mechanisms of drug addiction are not well understood, but have been proposed to involve neural plasticity and the remodeling of specific brain circuits. Accumulating evidence also indicates that patients addicted to methamphetamine exhibit impaired cognitive functions such as executive function, attention, social cognition, flexibility, and working memory. Furthermore, decision-making is altered in patients with drug addiction, including methamphetamine abusers. Cognitive impairment as well as altered decision-making in methamphetamine abusers may contribute to the high rate of relapse even after long-term withdrawal with psychosocial support. In this article, we review the effect of methamphetamine on cognition and decision-making in rodents. We also discuss possible mechanisms underlying cognition and decision-making impairments, including neuronal circuits, molecular and cellular events, and action control, as well as potential therapeutic targets.

DOI： 10.1016/j.neuint.2018.12.019