医学部 精神神経科学

saito takeo

  (齋藤 竹生)

Profile Information

Affiliation
School of Medicine Faculty of Medicine, Fujita Health University
Degree
医学博士(藤田医科大学)

J-GLOBAL ID
201501001954870181
researchmap Member ID
7000013117

Research History

 3

Papers

 46
  • Takuma Ashizawa, Takeo Saito, Tomo Okochi, Kohei Ninomiya, Kenta Ito, Rei Aoki, Masashi Ikeda, Nakao Iwata
    Translational Psychiatry, 14(1), Oct 14, 2024  
    Abstract Recent genome-wide association studies (GWASs) have identified fatty acid desaturase (FADS) genes, which code key enzymes involved in polyunsaturated fatty acid (PUFA) desaturation as susceptibility genes for bipolar disorder (BD). Several quantitative changes in PUFAs suggest their involvement in BD pathogenesis. Therefore, this study aimed to clarify the relationship between BD and PUFAs by conducting lipidomics covariating with the FADS gene variant (rs174550), which is associated with PUFA levels and BD susceptibility. The concentrations of 23 fatty acids were measured using plasma samples from the BD group (n = 535) and the control group (n = 107). Differences in each PUFA concentration ratio were compared between the two groups. Also, differences in each PUFA concentration ratio were compared for each genotype in rs174550. Our results showed that the BD group had significantly lower concentrations of linoleic acid (LA) (β = −0.36, p = 0.023) and arachidonic acid (AA) (β = −0.18, p = 0.013) than the control group. Concerning the effect of FADS on the PUFA concentration ratio, carriers of C-allele at rs174550 had significantly decreased γ-linolenic acid and AA concentration ratios. A previous GWAS reported that the presence of a C-allele at rs174550 increased the BD risk. This direction is consistent with the lipidomic results of the present study. In conclusion, both the FADS and BD were considered to regulate the AA concentration. Thus, as the FADS gene variant is crucial for conducting lipidomics of BD we believe that the allele frequency of FADS must be analyzed.
  • Masakazu Hatano, Haruna Araki, Takeo Saito, Shigeki Yamada
    Clinical psychopharmacology and neuroscience : the official scientific journal of the Korean College of Neuropsychopharmacology, 22(3) 442-450, Aug 31, 2024  
    OBJECTIVE: This pharmacovigilance study evaluated the profile of clozapine-related adverse events by region using the Food and Drug Administration Adverse Event Reporting System (FAERS). METHODS: We categorized each case into five regions (America, Europe/West Asia, Oceania, Asia, and Africa) based on the reporting country information in the FAERS database. The number of clozapine-related adverse events reported in each region was aggregated according to the preferred term (PT) and the Standardized Medical Dictionary for Regulatory Activities (MedDRA) Query (SMQ). RESULTS: A total of 101,872 clozapine-related adverse events were registered in the FAERS database. In America and Europe, leukocyte or neutrophil count abnormalities accounted for half of the top 10 PTs by relative reporting rate. However, Asia had higher relative reporting rates of pyrexia and salivary hypersecretion (13.91% and 10.85%, respectively). Regarding the SMQ, the relative reporting rates of infective pneumonia, convulsions, extrapyramidal syndrome, gastrointestinal obstruction, and hyperglycaemia/new onset diabetes mellitus were higher in Asia than in other regions (5.26%, 9.72%, 12.65%, 5.13%, and 8.26%, respectively), with significant differences even after adjusting for confounding factors using multivariate logistic regression analysis. CONCLUSION: Spontaneous reports of adverse events associated with clozapine show regional disparities, particularly in Asia, where concentration-dependent adverse events are more frequently reported. However, the spontaneous reporting system has several limitations, requiring further research for validation.
  • Hirona Yamamoto, Hyeon-Cheol Lee-Okada, Masashi Ikeda, Takumi Nakamura, Takeo Saito, Atsushi Takata, Takehiko Yokomizo, Nakao Iwata, Tadafumi Kato, Takaoki Kasahara
    Molecular Psychiatry, 28(7) 2848-2856, Feb 21, 2023  Peer-reviewed
    Abstract Large-scale genome-wide association studies (GWASs) on bipolar disorder (BD) have implicated the involvement of the fatty acid desaturase (FADS) locus. These enzymes (FADS1 and FADS2) are involved in the metabolism of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are thought to potentially benefit patients with mood disorders. To model reductions in the activity of FADS1/2 affected by the susceptibility alleles, we generated mutant mice heterozygously lacking both Fads1/2 genes. We measured wheel-running activity over six months and observed bipolar swings in activity, including hyperactivity and hypoactivity. The hyperactivity episodes, in which activity was far above the norm, usually lasted half a day; mice manifested significantly shorter immobility times on the behavioral despair test performed during these episodes. The hypoactivity episodes, which lasted for several weeks, were accompanied by abnormal circadian rhythms and a marked decrease in wheel running, a spontaneous behavior associated with motivation and reward systems. We comprehensively examined lipid composition in the brain and found that levels of certain lipids were significantly altered between wild-type and the heterozygous mutant mice, but no changes were consistent with both sexes and either DHA or EPA was not altered. However, supplementation with DHA or a mixture of DHA and EPA prevented these episodic behavioral changes. Here we propose that heterozygous Fads1/2 knockout mice are a model of BD with robust constitutive, face, and predictive validity, as administration of the mood stabilizer lithium was also effective. This GWAS-based model helps to clarify how lipids and their metabolisms are involved in the pathogenesis and treatment of BD.
  • Masakazu Hatano, Kaho Yamada, Haruna Matsuzaki, Rina Yokoi, Takeo Saito, Shigeki Yamada
    PloS one, 18(6) e0287122, 2023  
    Among antipsychotics, clozapine is associated with a high risk of seizures. This study aimed to generate novel hypotheses regarding trends in the onset of clozapine-induced seizures using the JADER (Japanese Adverse Drug Event Report) database. Seizures were defined according to the Standardized MedDRA Queries (SMQ) for convulsions (SMQ20000079). Trends in the onset of clozapine-induced seizures were assessed using multivariate logistic regression analysis with covariates of sex, age, clozapine dose, antipsychotic polypharmacy, concomitant medications, and history of convulsive disorder. In addition, we assessed the time-to-onset of clozapine-induced seizures using the median time, interquartile range, and Weibull shape parameter. The JADER database registered 2,745 cases of adverse events with clozapine, and 1,784 cases were included in the analysis after excluding cases for which clinical information was not available. Medium (200-400 mg) and high (> 400 mg) doses of clozapine had a significantly higher reporting rate of seizures than low doses (< 200 mg) (adjusted reporting odds ratio [aROR] = 3.05, 95% confidence interval [CI]: 1.86-4.99 and aROR = 9.81, 95% CI: 6.06-15.89, respectively). Younger age, antipsychotic polypharmacy, and concomitant use of lithium were also significantly associated with reports of seizures. The time-to-onset analysis of 222 cases of clozapine-induced seizures showed that the median time was 134 (interquartile range, 72-295) days. The 95% CI of the WSP β-value for clozapine-induced seizures included 1 and was classified as a random failure type. In conclusion, the results suggest that clozapine-induced seizures are dose-dependent adverse events that should be monitored with consideration of the effects of age and concomitant medications. Further epidemiological research is needed to strengthen and validate our hypotheses.
  • Haruna Matsuzaki, Masakazu Hatano, Miko Iwata, Takeo Saito, Shigeki Yamada
    Neuropsychiatric disease and treatment, 19 615-622, 2023  
    PURPOSE: Clozapine is more effective than other antipsychotics and is the only antipsychotic approved for treatment-resistant schizophrenia. The objective of this study is to reveal the effect of clozapine on employment using a bidirectional mirror-image model. PATIENTS AND METHODS: This design was a retrospective observational study that investigated the employment status of patients with treatment-resistant schizophrenia based on medical records. The bidirectional mirror-image model consisted of 1) switching from other antipsychotics to clozapine and 2) switching from clozapine to other antipsychotics. The observation period was 1 year for each pre- and post-clozapine initiation and discontinuation. RESULTS: We included 36 patients in the bidirectional mirror-image model. The regular employment plus employment support rate was significantly higher in the clozapine phase than in the other antipsychotic phase in the bidirectional mirror-image model (30.6% vs 11.1%, P = 0.039). The days of regular employment plus employment support were also significantly longer in the clozapine phase (61.3 ± 106.2 vs 24.7 ± 82.7 days, P = 0.032). As per the unidirectional mirror-image model, switching to clozapine resulted in significantly higher regular employment plus employment support rates in the clozapine phase than those in the other antipsychotic phase (33.3% vs 10.0%, P = 0.039). Switching from clozapine to other antipsychotics did not exhibit significant differences in any outcomes. CONCLUSION: The results suggest that clozapine is superior to other antipsychotics with respect to achieving employment in patients with treatment-resistant schizophrenia. However, biases specific to the mirror-image model need to be considered.

Misc.

 28
  • 芦澤 琢磨, 伊藤 健太, 二宮 光平, 齋藤 竹生, 池田 匡志, 岩田 仲生
    精神科臨床Legato, 7(3) 140-144, Dec, 2021  
    統合失調症の病態は依然として不明のままであり、現在に至るまでさまざまな切り口から多くの研究がなされてきた。近年、全ゲノム関連研究(genome-wide association study;GWAS)は疾患感受性遺伝子同定に大きく寄与し、病態研究の新たなヒントを与えている。本稿では統合失調症GWASの成果について触れる。(著者抄録)
  • 池田 匡志, 高橋 篤, 鎌谷 洋一郎, 桃沢 幸秀, 齋藤 竹生, 近藤 健治, 島崎 愛夕, 川瀬 康平, 作佐部 太也, 岩山 佳美, 豊田 倫子, 和久田 智靖, 菊池 充, 金原 信久, 山森 英長, 安田 由華, 渡部 雄一郎, 保谷 智史, アレクシッチ ブランコ, 久島 周, 新井 平伊, 高木 学, 服部 功太郎, 功刀 浩, 岡久 祐子, 大沼 徹, 尾崎 紀夫, 染矢 俊幸, 橋本 亮太, 吉川 武男, 久保 充明, 岩田 仲生
    日本臨床精神神経薬理学会・日本神経精神薬理学会合同年会プログラム・抄録集, 29回・49回 124-124, Oct, 2019  
  • 島崎 愛夕, 齋藤 竹生, 大河内 智, 谷口 賢, 二宮 光平, 橋本 亮太, 池田 匡志, 岩田 仲生, CPC-J日本クロザピン薬理ゲノム学コンソーシアム
    精神神経学雑誌, (2019特別号) S467-S467, Jun, 2019  
  • 菅原 裕子, 村田 唯, 池亀 天平, 嶋永 翔太, 竹岡 優将, 齋藤 竹生, 池田 匡志, 吉川 茜, 西村 文親, 河村 代志也, 垣内 千尋, 佐々木 司, 岩田 仲生, 橋本 衛, 笠井 清登, 加藤 忠史, 文東 美紀, 岩本 和也
    精神神経学雑誌, 121(4) 251-258, Apr, 2019  
    統合失調症(SZ)と双極性障害(BD)は遺伝要因と環境要因を共有することが知られており,複雑な遺伝環境相互作用が発症に関与すると考えられている.ゲノムワイド関連解析の結果,主要な精神疾患のなかでもSZとBDは遺伝要因の重なりが特に大きいことが知られているが,エピゲノム要因の重なりについては十分な検討がなされていない.本研究では,SZで行われた大規模なゲノムワイドメチル化関連解析(MWAS)で同定された上位5ヶ所の候補領域について,BD試料を用いた検討を行った.5ヶ所の候補領域のうち2ヶ所[FAM63B,染色体16番intergenic領域(IR in chr 16)]では,SZと同様に,BDにおいても有意な低メチル化状態が認められ,SZとBDに共通なエピゲノム要因である可能性が示唆された.また,1ヶ所(TBC1D22A)の領域では,SZとは異なり,BDでは健常者に比して有意な高メチル化状態が認められた.今後,BDを対象とした大規模なMWASによって,両疾患におけるエピゲノム要因の類似性や独自性の詳細がさらに明らかとなるであろう.(著者抄録)
  • 菅原 裕子, 村田 唯, 池亀 天平, 嶋永 翔太, 竹岡 優将, 齋藤 竹生, 池田 匡志, 吉川 茜, 西村 文親, 河村 代志也, 垣内 千尋, 佐々木 司, 岩田 仲生, 橋本 衛, 笠井 清登, 加藤 忠史, 文東 美紀, 岩本 和也
    精神神経学雑誌, 121(4) 251-258, Apr, 2019  
    統合失調症(SZ)と双極性障害(BD)は遺伝要因と環境要因を共有することが知られており,複雑な遺伝環境相互作用が発症に関与すると考えられている.ゲノムワイド関連解析の結果,主要な精神疾患のなかでもSZとBDは遺伝要因の重なりが特に大きいことが知られているが,エピゲノム要因の重なりについては十分な検討がなされていない.本研究では,SZで行われた大規模なゲノムワイドメチル化関連解析(MWAS)で同定された上位5ヶ所の候補領域について,BD試料を用いた検討を行った.5ヶ所の候補領域のうち2ヶ所[FAM63B,染色体16番intergenic領域(IR in chr 16)]では,SZと同様に,BDにおいても有意な低メチル化状態が認められ,SZとBDに共通なエピゲノム要因である可能性が示唆された.また,1ヶ所(TBC1D22A)の領域では,SZとは異なり,BDでは健常者に比して有意な高メチル化状態が認められた.今後,BDを対象とした大規模なMWASによって,両疾患におけるエピゲノム要因の類似性や独自性の詳細がさらに明らかとなるであろう.(著者抄録)

Research Projects

 3