研究者業績

橋本 直子

Naoko Hashimoto

基本情報

所属
千葉大学 大学院医学研究院 分子病態解析学 助教

J-GLOBAL ID
201901000100241671
researchmap会員ID
B000380399

外部リンク

私は千葉大学大学院医学研究院分子病態解析学講座で、加齢疾患やがんのコントロールにつながるp53の作用機序の解明を進めることを目指して研究を行っています。

老化や加齢疾患/生活習慣病の背景には、細胞老化が深く関与していると考えられていますが、がん抑制遺伝子p53は、がん以外にも細胞内代謝調節や臓器・個体老化の制御に関わることが分かってきました。また、近年、非コードRNAの研究が進む中、長鎖非コードRNA (lncRNA)がクロマチン修飾複合体と相互作用してエピジェネティックな転写制御に関わることが見いだされてきており、私たちは老化と加齢疾患/生活習慣病における老化関連lncRNAに着目して研究を進めているところです。

研究キーワード

 4

学歴

 2

論文

 76
  • Rafaela Muniz de Queiroz, Gizem Efe, Asja Guzman, Naoko Hashimoto, Yusuke Kawashima, Tomoaki Tanaka, Anil K Rustgi, Carol Prives
    Nature communications 15(1) 7132-7132 2024年8月20日  
    Although the E3 ligase Mdm2 and its homologue and binding partner MdmX are the major regulators of the p53 tumor suppressor protein, it is now evident that Mdm2 and MdmX have multiple functions that do not involve p53. As one example, it is known that Mdm2 can regulate cell migration, although mechanistic insight into this function is still lacking. Here we show in cells lacking p53 expression that knockdown of Mdm2 or MdmX, as well as pharmacological inhibition of the Mdm2/MdmX complex, not only reduces cell migration and invasion, but also impairs cell spreading and focal adhesion formation. In addition, Mdm2 knockdown decreases metastasis in vivo. Interestingly, Mdm2 downregulates the expression of Sprouty4, which is required for the Mdm2 mediated effects on cell migration, focal adhesion formation and metastasis. Further, our findings indicate that Mdm2 dampening of Sprouty4 is a prerequisite for maintaining RhoA levels in the cancer cells that we have studied. Taken together we describe a molecular mechanism whereby the Mdm2/MdmX complex through Sprouty4 regulates cellular processes leading to increase metastatic capability independently of p53.
  • Satomi Kono, Hidekazu Nagano, Yuki Taki, Takashi Kono, Naoko Hashimoto, Yasuhiro Nakamura, Naoko Inoshita, Masayuki Ohtsuka, Tomoaki Tanaka
    Endocrine and Metabolic Science 15 2024年6月30日  
    Objective: Pancreatic neuroendocrine neoplasms (pNENs) are histologically classified as well-differentiated, poorly-differentiated, or mixed neuroendocrine-non-neuroendocrine neoplasms. There are unresectable pNENs owing to metastases or invasion in not only functional pNENs but also non-functional. However, the exact origin of pNENs has not been elucidated. This study aims to characterize the molecular biology of pNENs based on clinical information and histopathological analysis and identify prognostic biomarkers. Methods: We investigated the relationship between the biological characteristics and immunostaining of pathological tissues in 75 patients. Staining density was evaluated on a 4-point scale from 0 to 3, and the percentage of tumor cells was calculated and scored from 0 to 300 (H-score). We performed receiver operating characteristic (ROC) curve analysis of the H-score. Progression-free survival and overall survival analyses were performed based on the Kaplan–Meier curves. Results: The H-score showed that patients who died of pNEN had high Ki-67 and low somatostatin receptor (SSTR) 2 levels, and those who relapsed had high Ki-67 and low SSTR5 levels. The ROC showed that the SSTR2 H-score > 80.25 was associated with lower mortality, which was further confirmed by Kaplan–Meier curves [hazard ratio (HR): 6.039, 95 % confidence interval (CI): 1.233–29.59, P = 0.0006). SSTR5 H-score > 93.9 had less recurrence, which was confirmed using Kaplan–Meier curves (HR: 3.321, 95 % CI: 1.426–7.734, P = 0.0336). Conclusion: Ki-67 > 4.95 is associated with a significantly increased risk of death. Quantification of SSTR2 and SSTR5 immunostaining using the H-score may serve as prognostic markers.
  • 榊原 隆次, 澤井 摂, 天谷 亮介, 吉岡 さくら, 大友 利輝, 松本 紋子, 永野 秀和, 橋本 直子, 田中 知明
    千葉医学雑誌 100(2) 37-37 2024年4月  
  • Ryosuke Amagai, Riki Otomo, Sakura Yoshioka, Hidekazu Nagano, Naoko Hashimoto, Ryuji Sakakibara, Tomoaki Tanaka, Ayako Okado-Matsumoto
    Journal of biochemistry 2024年2月2日  
    α-Synuclein is a protein related to synucleinopathies with high expression in the central nervous system and erythrocytes which are a major source of peripheral α-synuclein. Recent reports have suggested the presence of α-synuclein within extracellular vesicles derived from erythrocytes, potentially contributing to the pathogenesis of synucleinopathies. While Lewy bodies, intracellular inclusions containing aggregated α-synuclein, are prominently observed within the brain, their occurrence in peripheral neurons implies the dissemination of synucleinopathy pathology throughout the body via the propagation of α-synuclein. In this study, we found erythrocytes and circulating extracellular vesicles obtained from plasma contained α-synuclein, which was separated into four major forms using high-resolution clear native-PAGE and isoelectric focusing. Notably, erythrocyte α-synuclein was classified into full-length and C-terminal truncated forms, with truncation observed between Y133 and Q134 as determined by LC-MS/MS analysis. Our finding revealed that C-terminally truncated α-synuclein, which was previously reported to exist solely within the brain, was also present in erythrocytes and circulating extracellular vesicles obtained from plasma.
  • 瀧 由樹, 河野 貴史, 河野 聡美, 藤本 真徳, 橋本 直子, 永野 秀和, 田中 知明
    日本内分泌学会雑誌 99(2) 628-628 2023年10月  
  • 中山 哲俊, 横山 真隆, 宮 英博, 石 暁彦, 永野 秀和, 山形 一行, 橋本 直子, 渕上 孝裕, 田中 知明
    日本癌学会総会記事 82回 2008-2008 2023年9月  
  • 松田 達磨, 高 躍, 堀口 健太郎, 河野 貴史, 藤本 真徳, 橋本 直子, 永野 秀和, 井下 尚子, 山田 正三, 岩立 康男, 田中 知明
    日本内分泌学会雑誌 99(Suppl.HPT) 76-79 2023年8月  
    エナメル上皮型頭蓋咽頭腫の病態については、これまでCTNNB1変異に伴うWnt signal活性など少しずつ解明が進んでいるが、まだ全容解明には至っていない。その要因の一つとして、腫瘍内部は非常にheterogeneityに富んでおり、これまでのbulk検体を対象とした検討では腫瘍細胞本来の性質が隠されてしまうことが挙げられる。今回、この問題をブレイクスルーするシングルセル解析法を用いて本症の病態解明を試みた。その結果、本症の腫瘍細胞には2つのsubtype(Immune rich typeとProliferative epithelial type)があり、それぞれ異なる分子生物学的背景が存在することが明らかになった。
  • Ikki Sakuma, Hidekazu Nagano, Naoko Hashimoto, Masanori Fujimoto, Akitoshi Nakayama, Takahiro Fuchigami, Yuki Taki, Tatsuma Matsuda, Hiroyuki Akamine, Satomi Kono, Takashi Kono, Masataka Yokoyama, Motoi Nishimura, Koutaro Yokote, Tatsuki Ogasawara, Yoichi Fujii, Seishi Ogawa, Eunyoung Lee, Takashi Miki, Tomoaki Tanaka
    Communications biology 6(1) 787-787 2023年7月28日  査読有り
    Fructose-1,6-bisphosphatase (FBPase) deficiency, caused by an FBP1 mutation, is an autosomal recessive disorder characterized by hypoglycemic lactic acidosis. Due to the rarity of FBPase deficiency, the mechanism by which the mutations cause enzyme activity loss still remains unclear. Here we identify compound heterozygous missense mutations of FBP1, c.491G>A (p.G164D) and c.581T>C (p.F194S), in an adult patient with hypoglycemic lactic acidosis. The G164D and F194S FBP1 mutants exhibit decreased FBP1 protein expression and a loss of FBPase enzyme activity. The biochemical phenotypes of all previously reported FBP1 missense mutations in addition to G164D and F194S are classified into three functional categories. Type 1 mutations are located at pivotal residues in enzyme activity motifs and have no effects on protein expression. Type 2 mutations structurally cluster around the substrate binding pocket and are associated with decreased protein expression due to protein misfolding. Type 3 mutations are likely nonpathogenic. These findings demonstrate a key role of protein misfolding in mediating the pathogenesis of FBPase deficiency, particularly for Type 2 mutations. This study provides important insights that certain patients with Type 2 mutations may respond to chaperone molecules.
  • 神津 隆之介, 藤本 真徳, 横山 真隆, 河野 貴史, 瀧 由樹, 永野 秀和, 橋本 直子, 田中 知明
    日本内分泌学会雑誌 99(1) 303-303 2023年5月  
  • 中山 哲俊, 横山 真隆, 永野 秀和, 山形 一行, 橋本 直子, 田中 知明
    日本内分泌学会雑誌 99(1) 339-339 2023年5月  
  • 石 暁彦, 橋本 直子, 山形 一行, 横山 真隆, 関 直彦, 田中 知明
    日本内分泌学会雑誌 99(1) 339-339 2023年5月  
  • 松田 達磨, 高 躍, 河野 貴史, 藤本 真徳, 橋本 直子, 永野 秀和, 井下 尚子, 山田 正三, 岩立 康男, 田中 知明
    日本内分泌学会雑誌 99(1) 347-347 2023年5月  
  • 河野 貴史, 瀧 由樹, 河野 聡美, 藤本 真徳, 永野 秀和, 橋本 直子, 田中 知明
    日本内分泌学会雑誌 99(1) 348-348 2023年5月  
  • 橋本 直子, 山形 一行, 石 暁彦, 藤本 真徳, 中山 哲俊, 横山 真隆, 田中 知明
    日本内分泌学会雑誌 99(1) 413-413 2023年5月  
  • 河野 聡美, 永野 秀和, 瀧 由樹, 藤本 真徳, 河野 貴史, 橋本 直子, 井下 尚子, 田中 知明
    日本内分泌学会雑誌 99(1) 416-416 2023年5月  
  • 瀧 由樹, 河野 貴史, 照山 杏子, 一城 貴政, 河野 聡美, 高 躍, 藤本 真徳, 橋本 直子, 佐久間 一基, 永野 秀和, 田中 知明
    日本内分泌学会雑誌 99(1) 398-398 2023年5月  
  • Motoi Nishimura, Tomoaki Tanaka, Syota Murata, Akiko Miyabe, Takayuki Ishige, Kenji Kawasaki, Masataka Yokoyama, Naoko Hashimoto, Kazuyuki Yamagata, Hidekazu Nagano, Satomi Tojo-Nishimura, Kazuyuki Matsushita
    Scientific reports 13(1) 5731-5731 2023年4月7日  査読有り
    Although polymerase chain reaction (PCR) amplification and sequencing of the bacterial 16S rDNA region has numerous scientific applications, it does not provide DNA methylation information. Herein, we propose a simple extension for bisulfite sequencing to investigate 5-methylcytosine residues in the bacterial 16S rDNA region from clinical isolates or flora. Multiple displacement amplification without DNA denaturation was used to preferentially pre-amplify single-stranded bacterial DNA after bisulfite conversion. Following the pre-amplification, the 16S rDNA region was analyzed using nested bisulfite PCR and sequencing, enabling the simultaneous identification of DNA methylation status and sequence data. We used this approach (termed sm16S rDNA PCR/sequencing) to identify novel methylation sites and a methyltransferase (M. MmnI) in Morganella morganii and different methylation motifs among Enterococcus faecalis strains from small volumes of clinical specimens. Further, our analysis suggested that M. MmnI may be correlated to erythromycin resistance. Thus, sm16S rDNA PCR/sequencing is a useful extension method for analyzing the DNA methylation of 16S rDNA regions in a microflora, providing additional information not provided by conventional PCR. Given the relationship between DNA methylation status and drug resistance in bacteria, we believe this technique can be effectively applied in clinical sample testing.
  • Ryosuke Amagai, Sakura Yoshioka, Riki Otomo, Hidekazu Nagano, Naoko Hashimoto, Ryuji Sakakibara, Tomoaki Tanaka, Ayako Okado-Matsumoto
    Journal of biochemistry 173(3) 177-184 2023年3月7日  査読有り
    α-Synuclein is a protein linked to various synuclein-associated diseases ('synucleinopathies'), including Parkinson's disease, dementia with Lewy Bodies and multiple system atrophy, and is highly expressed in the central nervous system and in erythrocytes. Moreover, α-synuclein-containing erythrocyte-derived extracellular vesicles may be involved in the pathogenesis of synucleinopathies and their progression across the blood-brain barrier. Several post-translational modifications of α-synuclein have been reported in brain inclusions, including S129 phosphorylation, but fewer have been found in erythrocytes. In this study, we analysed the post-translational modifications of erythrocyte α-synuclein using liquid chromatography-mass spectrometry. We found that all lysine residues in the α-synuclein protein could be modified by acetylation, glycation, ubiquitination or SUMOylation but that phosphorylation, nitration and acylation were uncommon minor post-translational modifications in erythrocytes. Since the post-translational modification of lysine residues has been implicated in both membrane association and protein clearance, our findings provide new insight into how synucleinopathies may progress and suggest possible therapeutic strategies designed to target α-synuclein.
  • 倉田 理華, 河野 貴史, 河野 聡美, 橋本 直子, 永野 秀和, 桑原 憲一, 田中 知明
    日本内分泌学会雑誌 98(4) 867-867 2023年2月  
  • 松田 達磨, 高 躍, 堀口 健太郎, 河野 貴史, 藤本 真徳, 橋本 直子, 永野 秀和, 岩立 康男, 田中 知明
    日本内分泌学会雑誌 98(4) 907-907 2023年2月  
  • 高 躍, 松田 達磨, 藤本 真徳, 中山 哲俊, 橋本 直子, 山形 一行, 横山 真隆, 堀口 健太郎, 岩立 康男, 田中 知明
    日本内分泌学会雑誌 98(4) 908-908 2023年2月  
  • 瀧 由樹, 河野 貴史, 照山 杏子, 一城 貴政, 河野 聡美, 高 躍, 藤本 真徳, 橋本 直子, 佐久間 一基, 永野 秀和, 田中 知明
    日本内分泌学会雑誌 98(4) 912-912 2023年2月  
  • Azusa Yamato, Hidekazu Nagano, Yue Gao, Tatsuma Matsuda, Naoko Hashimoto, Akitoshi Nakayama, Kazuyuki Yamagata, Masataka Yokoyama, Yingbo Gong, Xiaoyan Shi, Siti Nurul Zhahara, Takashi Kono, Yuki Taki, Naoto Furuki, Motoi Nishimura, Kentaro Horiguchi, Yasuo Iwadate, Masaki Fukuyo, Bahityar Rahmutulla, Atsushi Kaneda, Yoshinori Hasegawa, Yusuke Kawashima, Osamu Ohara, Tetsuo Ishikawa, Eiryo Kawakami, Yasuhiro Nakamura, Naoko Inoshita, Shozo Yamada, Noriaki Fukuhara, Hiroshi Nishioka, Tomoaki Tanaka
    Communications biology 5(1) 1304-1304 2022年11月27日  査読有り
  • Alimasi Aersilan, Naoko Hashimoto, Kazuyuki Yamagata, Masataka Yokoyama, Akitoshi Nakayama, Xiaoyan Shi, Hidekazu Nagano, Ikki Sakuma, Nijiro Nohata, Takashi Kinoshita, Naohiko Seki, Bahityar Rahmutulla, Atsushi Kaneda, Siti Nurul Zhahara, Yingbo Gong, Motoi Nishimura, Shoichiro Kawauchi, Eiryo Kawakami, Tomoaki Tanaka
    Scientific reports 12(1) 18443-18443 2022年11月2日  査読有り筆頭著者
    The microRNA (miR) miR-874, a potential tumour suppressor, causes cell death via target gene suppression in various cancer types. Mevalonate pathway inhibition also causes cell death in breast cancer. However, the relationship between the mevalonate pathway and miR-874-induced apoptosis or its association with the tumour suppressor p53 has not been elucidated. We identified phosphomevalonate kinase (PMVK), a key mevalonate pathway enzyme, and sterol regulatory element-binding factor 2 (SREBF2), the master cholesterol biosynthesis regulator, as direct miR‑874 targets. Next-generation sequencing analysis revealed a significant miR-874-mediated downregulation of PMVK and SREBF2 gene expression and p53 pathway enrichment. Luciferase reporter assays showed that miR-874 directly regulated PMVK and SREBF2. miR-874-induced apoptosis was p53 dependent, and single-cell RNA sequencing analysis demonstrated that miR-874 transfection resulted in apoptosis and p53 pathway activation. Downregulation of PMVK expression also caused cell cycle arrest and p53 pathway activation, which was rescued by geranylgeranyl pyrophosphate (GGPP) supplementation. Analysis of The Cancer Genome Atlas (TCGA) database indicated a negative correlation between miR-874 and PMVK expression and between miR-874 and SREBF2 expression. These findings suggest that miR-874 suppresses the mevalonate pathway by targeting SREBF2 and PMVK, resulting in GGPP depletion, which activates the p53 pathway and promotes cycle arrest or apoptosis.
  • Masanori Fujimoto, Masataka Yokoyama, Masahiro Kiuchi, Hiroyuki Hosokawa, Akitoshi Nakayama, Naoko Hashimoto, Ikki Sakuma, Hidekazu Nagano, Kazuyuki Yamagata, Fujimi Kudo, Ichiro Manabe, Eunyoung Lee, Ryo Hatano, Atsushi Onodera, Kiyoshi Hirahara, Koutaro Yokote, Takashi Miki, Toshinori Nakayama, Tomoaki Tanaka
    Nature communications 13(1) 5408-5408 2022年9月15日  査読有り
    The liver stores glycogen and releases glucose into the blood upon increased energy demand. Group 2 innate lymphoid cells (ILC2) in adipose and pancreatic tissues are known for their involvement in glucose homeostasis, but the metabolic contribution of liver ILC2s has not been studied in detail. Here we show that liver ILC2s are directly involved in the regulation of blood glucose levels. Mechanistically, interleukin (IL)-33 treatment induces IL-13 production in liver ILC2s, while directly suppressing gluconeogenesis in a specific Hnf4a/G6pc-high primary hepatocyte cluster via Stat3. These hepatocytes significantly interact with liver ILC2s via IL-13/IL-13 receptor signaling. The results of transcriptional complex analysis and GATA3-ChIP-seq, ATAC-seq, and scRNA-seq trajectory analyses establish a positive regulatory role for the transcription factor GATA3 in IL-13 production by liver ILC2s, while AP-1 family members are shown to suppress IL-13 release. Thus, we identify a regulatory role and molecular mechanism by which liver ILC2s contribute to glucose homeostasis.
  • 橋本 直子, 山形 一行, 横山 真隆, 石 曉彦, 村田 和貴, 関 直彦, 田中 知明
    日本内分泌学会雑誌 98(1) 403-403 2022年4月  
  • 中山 哲俊, 横山 真隆, 永野 秀和, 橋本 直子, 山形 一行, 村田 和貴, 田中 知明
    日本癌学会総会記事 80回 [P4-3] 2021年9月  
  • 山形 一行, 田村 愛, 長濱 博章, 藤本 真徳, 中山 哲俊, 横山 真隆, 橋本 直子, 村田 和貴, 西村 基, 田中 知明
    日本内分泌学会雑誌 97(3) 642-642 2021年7月  
  • Akitoshi Nakayama, Masataka Yokoyama, Hidekazu Nagano, Naoko Hashimoto, Kazuyuki Yamagata, Kazutaka Murata, Tomoaki Tanaka
    Journal of the Endocrine Society 5(Supplement_1) A1026-A1026 2021年5月3日  
    <title>Abstract</title> In many cancers, including hormone sensitive tumors such as breast cancer, the “gain of function” caused by mutations in the tumor suppressor gene p53 plays an important role in the acquisition of malignant phenotypes and the regulation of cancer stem cell characteristics. However, its action of molecular mechanisms, particularly in vivo conditions, has not been fully clarified. Therefore, we focused on the “gain of function” of mutant p53 and the cholesterol biosynthesis pathway, especially the mevalonate(MVA) pathway, using breast cancer cells, and clarified the interaction between them and the relationship with cancer malignancy using 3D-culture. Here, we generated knock out and knock in breast cancer cell lines for p53 using CRISPR-Cas9 system, and then confirmed malignant morphological changes by 3D-culture model. We found that the introduction of mutant p53 was solely able to mediate the malignant transformation of cancer. Next, focusing on the relationship between cancer malignant transformation and lipid metabolism pathway, we investigated the role of the MVA pathway in malignant transformation by mutation p53. When investigating the effects of the addition of HMG-CoA inhibitors and isoprenoids, intermediate metabolites were important for malignant transformation during 3D culture. Furthermore, knockdown of SREBP2, which controls the MVA pathway, suppressed malignant phenotypes, so we proceeded with analysis of the interaction between mutant p53 and SREBP2. As the result, we found that mutant p53 and SREBP2 co-localize in the nucleus and consistently mutant p53 was associated with mevalonate pathway genes in parallel with binding pattern of SREBP2. Thus, our results provide the novel insight into the potential therapeutic targets for breast cancer with poor prognosis.
  • Hanna Deguchi-Horiuchi, Hisashi Koide, Ikki Sakuma, Yue Gao, Seiichiro Higuchi, Hidekazu Nagano, Naoko Hashimoto, Kentaro Horiguchi, Yasuo Iwadate, Naoko Inoshita, Koutaro Yokote, Tomoaki Tanaka
    Endocrine journal 68(3) 269-279 2021年3月28日  査読有り
    Rathke's cleft cyst (RCC) is a common incidental tumor in the hypothalamic-pituitary region. Some reports have shown that the clinical symptoms and endocrine functions of symptomatic RCCs are temporarily improved by glucocorticoid administration. However, it is still unknown whether glucocorticoid treatment is effective for symptomatic RCCs according to long-term observations. In this study, we describe the long-term clinical outcomes of two cases of glucocorticoid-treated biopsy-proven secondary hypophysitis caused by RCCs. We summarize the symptoms, imaging findings, and endocrine evaluations of two symptomatic RCC patients with concomitant hypophysitis before and after prednisolone treatment. In both evaluated cases, visual impairments and altered endocrine parameters were present due to chiasm and stalk compression; these outcomes improved after shrinkage of RCCs in response to prednisolone administration, and partial recovery of anterior pituitary hormone secretion was observed. However, in both cases, the deficits in anterior pituitary hormone secretion recurred, possibly due to persistent inflammatory infiltration in the RCCs and pituitary glands. After relapse of hypophysitis, anterior hormone secretion did not fully recover. In our cases of secondary hypophysitis caused by RCCs, prednisolone administration had an early effect of cyst shrinkage, followed by partial improvements in clinical symptoms and pituitary functions. However, long-term observation showed that prednisolone treatment did not contribute to complete improvement in anterior pituitary hormone dysfunction.
  • Ochiiwa H, Ailiken G, Yokoyama M, Yamagata K, Nagano H, Yoshimura C, Muraoka H, Ishida K, Haruma T, Nakayama A, Hashimoto N, Murata K, Nishimura M, Kawashima, Y, Ohara O, Okubo S, Tanaka T
    Oncogene 2020年11月  査読有り
  • 大和 梓, 永野 秀和, 橋本 直子, 山形 一行, 福世 真樹, 金田 篤志, 小原 収, 長谷川 嘉則, 福原 紀明, 西岡 宏, 山田 正三, 田中 知明
    日本内分泌学会雑誌 96(2) 502-502 2020年10月  
  • 樋口 誠一郎, 高 躍, 姚 躍, 大和 梓, 橋本 直子, 永野 秀和, 中山 哲俊, 西村 基, 山形 一行, 横山 真隆, 藤井 陽一, 小川 誠司, 田中 知明
    日本内分泌学会雑誌 96(1) 283-283 2020年8月  
  • 大和 梓, 永野 秀和, 山形 一行, 橋本 直子, 高 躍, 岩立 康男, 福世 真樹, 金田 篤志, 井下 尚子, 福原 紀章, 西岡 宏, 山田 正三, 田中 知明
    日本内分泌学会雑誌 96(1) 249-249 2020年8月  
  • Akitoshi Nakayama, Masataka Yokoyama, Hidekazu Nagano, Ikki Sakuma, Naoko Hashimoto, Seiichiro Higuchi, Kazuyuki Yamagata, Tomoaki Tanaka
    Journal of the Endocrine Society 4(Supplement_1) 2020年5月8日  
    <title>Abstract</title> p53 is mutated more than half of human cancers, and mutant p53, a gain of function, can actively have functional consequences with tumorigenesis. However, its action of molecular mechanisms, particularly in vivo conditions, has not been fully are clarified. Here, we generated KO and KI (R280K) breast cancer cell lines for p53 using CRISPR/Cas9 system, and then performed a three-dimensional culture model. We found that the introduction of mutant p53 was solely able to mediate the transformation to poor architectural structure. Interestingly, our findings in statin-effect along with cholesterol synthesis pathway, especially isoprenoid dependency, revealed that this pathway is necessary and sufficient for the regulation of malignant architecture in SREBP2-dependent manner with cooperatively being controlled by mutant p53 on 3D-cultured breast cancer. Furthermore, in accordance with the malignancy progresses, SREBP2 was accumulated in nuclear and nuclear membrane portion with enhancement in malignant formation. In addition, we found that mutant p53 interacts with SREBP2, and consistently mutant p53 was associated with DHCR7 promoter in parallel with binding pattern of SREBP2. Thus, our results provide the novel insight into the mutant p53, a gain of function, and its linkage to poor architectural structure in 3D-cultured breast cancer cells via SREBP2-dependent isoprenoids regulation as potential therapeutic targets.
  • Ikki Sakuma, Masataka Yokoyama, Kazuyuki Yamagata, Naoko Hashimoto, Akitoshi Nakayama, Gerald I Shulman, Tomoaki Tanaka
    Journal of the Endocrine Society 4(Supplement_1) 2020年5月8日  
    <title>Abstract</title> Iron is an essential cofactor for many proteins that function in electron transport or oxygen transport as heme or iron-sulfur cluster. On the contrary, iron also has the potential to cause oxidative damage if not carefully regulated and when in labial iron excess. Clinical studies show that elevated serum ferritin levels are observed in most patients with type 2 diabetes and non-alcoholic fatty liver disease (NAFLD). In this context, p53 is shown to induces some mitochondrial iron regulatory genes. The role of crosstalk between p53 and iron metabolism has not been sufficiently examined in the pathogenesis of diabetes and NAFLD. Here, we examined the role of ferredoxin reductase (FDXR), a key mitochondrial regulator for iron metabolism, as p53-inducible gene with focusing on the hepatocyte and liver. We confirmed that p53 induced FDXR expression in HepG2 cells and SKEHP1 cells. Biochemical analysis demonstrated that FDXR regulated ROS levels via iron metabolism. In vivo analysis, high-fat diet activated the p53-FDXR pathway in mice liver. We generated transgene expression in mice liver using adenovirus infection carrying shRNA or CRISPR Cas9 system. Treatment with the FDXR knockdown increased hepatic iron content and aggravated glucose intolerance. Besides, forkhead box protein O1 (FOXO1), a key transcriptional factor that induces phosphoenolpyruvate carboxylase and glucose-6-phosphatase increased ratio of nuclear localization, indicating hepatic gluconeogenesis activation. Consistently, biochemical analysis in HepG2 cells demonstrated that FDXR regulated insulin-dependent FOXO1 nuclear exclusion through oxidative stress. In conclusion, p53-inducible FDXR regulates iron metabolism and oxidative stress. FDXR inhibits iron accumulation and oxidative stress in liver and links to suppression of hepatic gluconeogenesis via insulin-dependent FOXO1 nuclear exclusion. The results of this study provide important new insights into relationship between iron metabolism and glucose metabolism as well as potentially identify novel therapeutic targets for the treatment of diabetes and NAFLD.
  • Yue Gao, Hidekazu Nagano, Kentaro Horiguchi, Naoko Hashimoto, Akitoshi Nakayama, Seiichiro Higuchi, Kazuyuki Yamagata, Masataka Yokoyama, Yasuo Iwadate, Tomoaki Tanaka
    Journal of the Endocrine Society 4(Supplement_1) 2020年5月8日  
    <title>Abstract</title> Objective: To clarify the relationship between proteomic expression and clinical feature of pituitary adenoma. Methods: We have previously developed non-target proteomics analysis, which enables to detect and quantify approximately 7,000 to 9,000 kinds of protein weave, in parallel with RNA-seq analysis, and then subjected to 14 cases of pituitary adenoma surgically removed at Chiba University Hospital. Bioinformatic evaluation including DEGs, heatmap and PCA analyses was performed to reveal underlying their molecular pathogenesis. Results: We successfully identified 789 differentially expressed proteins and 593 DEGs in non-target proteomics and RNA-seq, respectively. Intriguingly, PCA analysis demonstrated that tumors were clearly divided into 3 groups based on protein expression profile; functional pituitary adenomas consisting of two subtypes depending on Pit1 and T-pit linage, and non-functional tumors consisting of two distinct subtypes, with properties close to functional tumors and unique characteristics of hard tumor difficult to remove by endoscopic surgery. To address the underlying molecular biological functions in each group clustering analysis and heat-map were performed and we found that 3 groups were separated clearly with their own both gene and protein expression profile. Indeed, for instance, GO term of plasma membrane part was significantly enriched in hard tumor group, pathways of GH receptor signaling, GH hormone synthesis as in GH-positive group. Conclusions: We herein demonstrate that pituitary adenoma can be uniquely separated into certain categories through our novel non-target proteomics with coupling to RNA-seq, particularly providing novel group of hard tumor characteristics with enriched expression of both protein and mRNA in plasma membrane part. Thus our method would be beneficial and useful to elucidate underlying molecular pathogenesis for pituitary tumors, while further analysis is required.
  • Hidekazu Nagano, Takashi Kono, Atsushi Saiga, Yoshihiro Kubota, Masanori Fujimoto, Saulo J A Felizola, Kazuki Ishiwata, Ai Tamura, Seiichiro Higuchi, Ikki Sakuma, Naoko Hashimoto, Sawako Suzuki, Hisashi Koide, Nobushige Takeshita, Shinichi Sakamoto, Toshiaki Ban, Koutaro Yokote, Yasuhiro Nakamura, Tomohiko Ichikawa, Takashi Uno, Tomoaki Tanaka
    The Journal of clinical endocrinology and metabolism 105(3) 2020年3月1日  査読有り
    OBJECTIVE: Accurate assessment and localization of aldosterone-producing adenomas (APAs) are essential for the treatment of primary aldosteronism (PA). Although adrenal venous sampling (AVS) is the standard method of reference for subtype diagnosis in PA, controversy exists concerning the criteria for its interpretation. This study aims to determine better indicators that can reliably predict subtypes of PA. METHOD: Retrospective, single-cohort analysis including 209 patients with PA who were subjected to AVS. Eighty-two patients whose plasma aldosterone concentrations (PAC) were normalized after surgery were histopathologically or genetically diagnosed with APA. The accuracy of image findings was compared to AVS results. Receiver operating characteristic (ROC) curve analysis between the operated and the no-apparent laterality groups was performed using AVS parameters and loading test for diagnosis of PA. RESULT: Agreement between image findings and AVS results was 56.3%. ROC curve analysis revealed that the lateralization index (LI) after adrenocorticotropin stimulation cutoff was 2.40, with 98.8% sensitivity and 97.1% specificity. The contralateral suppression index (CSI) cutoff value was 1.19, with 98.0% sensitivity and 93.9% specificity. All patients over the LI and CSI cutoff values exhibited unilateral subtypes. Among the loading test, the best classification accuracy was achieved using the PAC reduction rate after a saline infusion test (SIT) >33.8%, which yielded 87.2% sensitivity or a PAC after a SIT <87.9 pg/mL with 86.2% specificity for predicting bilateral PA. CONCLUSION: The combined criteria of the PAC reduction rate and PAC after the SIT can determine which subset of patients with APA who should be performed AVS for validation.
  • Tomohiko Yoshida, Akitoshi Nakayama, Ai Tamura, Seiichiro Higuchi, Ikki Sakuma, Hidekazu Nagano, Saulo Ja Felizola, Naoko Hashimoto, Minoru Takemoto, Ichiro Tatsuno, Hisashi Koide, Koutaro Yokote, Tomoaki Tanaka
    The Journal of clinical endocrinology and metabolism 105(2) 2020年2月1日  査読有り
    CONTEXT: Hashimoto's thyroiditis is the most common cause of hypothyroidism. Patients usually respond well to oral synthetic thyroxine (levothyroxine); however, for unknown reasons some individuals present with treatment-resistant Hashimoto thyroiditis. In cases of cancer and certain infectious diseases, the ATP binding cassette (ABC) transporters have been implicated in multidrug resistance, and we hypothesized and investigated a role of ABC transporters in drug-resistant Hashimoto's thyroiditis. CASE DESCRIPTION: The patient whose case we report had a history of Hashimoto's thyroiditis, immune thrombocytopenia, and refractory hypertension, with varying treatment resistance to the oral medications prescribed for each condition. In order to establish or exclude a genetic basis for her illness, we examined the patient's gene expression profiles using peripheral blood leukocytes, and found that ABCG2/BCRPexpression was significantly high compared with healthy volunteers. Also, the increased daunomycin efflux capacity of our patient's lymphocytes was successfully inhibited by fumitremorgin C, a specific ABCG2/BCRP inhibitor, and the patient's level of thyroid-stimulating hormone increased by 248.6% after administration of intact levothyroxine tablets but decreased by 45.1% when tablets were crushed. Her average blood pressure decreased from 166.3/108.5 mmHg to 125.9/78.8 mmHg when switching from intact to crushed losartan tablets. CONCLUSIONS: High expression and accelerated efflux transporter activity of ABCG2/BCRP in the small intestine are expected to contribute to the ineffectiveness of orally administered intact tablets in cases with treatment-resistant Hashimoto's thyroiditis, and crushed tablets can be more effective for some of these patients.
  • Yoshida, T., Nakayama, A., Tamura, A., Higuchi, S., Sakuma, I., Nagano, H., Felizola, S.J.A., Hashimoto, N., Takemoto, M., Tatsuno, I., Koide, H., Yokote, K., Tanaka, T.
    Journal of Clinical Endocrinology and Metabolism 105(4) 2020年  
  • Naoko Hashimoto, Hidekazu Nagano, Tomoaki Tanaka
    Endocrine journal 66(6) 485-496 2019年6月28日  査読有り筆頭著者
    The tumor suppressor gene p53 is mutated in approximately more than 50% of human cancers. p53 is also referred to as the "cellular gatekeeper" or "guardian of the genome" because it protects the body from spreading mutated genome induced by various stress. When the cells receives stimuli such as DNA damage, oncogene activation, oxidative stress or undernutrition, p53 gives rise to a number of cellular responses, including cell cycle arrest, apoptosis, cellular senescence and metabolic adaptation. Related to energy metabolisms, it has been reported that p53 reduces glycolysis and enhances mitochondrial respiration. p53 is also involved in the regulation of other cellular metabolism and energy production systems: amino acid metabolism, fatty acid metabolism, nucleic acid metabolism, anti-oxidation, mitochondrial quality control, and autophagy. Moreover, recent studies have shown that p53 gene polymorphisms affect life expectancy and lifestyle-related disease such as type 2 diabetes, suggesting that there is a certain relationship between p53 function and metabolic disorders. In addition, mutant p53 protein does not only lose the tumor suppressor function, but it also gains novel oncogenic function and contributes to tumor development, involving cellular metabolism modification. Therefore, the importance of multifunctionality of p53, particularly with regard to intracellular metabolisms, arouses therapeutic interest and calls attention as the key molecule among cancer, lifestyle-related diseases and life expectancy.
  • 石田 晶子, 姚 躍, 宮林 佑衣, 中山 哲俊, 永野 秀和, 橋本 直子, 鈴木 佐和子, 西村 基, 小出 尚史, 木村 伯子, 小笠原 辰樹, 藤井 陽一, 小川 誠司, 田中 知明, 横手 幸太郎
    日本内分泌学会雑誌 94(2) 703-703 2018年9月  
  • Hidekazu Nagano, Naoko Hashimoto, Akitoshi Nakayama, Sawako Suzuki, Yui Miyabayashi, Azusa Yamato, Seiichiro Higuchi, Masanori Fujimoto, Ikki Sakuma, Minako Beppu, Masataka Yokoyama, Yutaka Suzuki, Sumio Sugano, Kazuhiro Ikeda, Ichiro Tatsuno, Ichiro Manabe, Koutaro Yokote, Satoshi Inoue, Tomoaki Tanaka
    Proceedings of the National Academy of Sciences of the United States of America 115(33) 8370-8375 2018年8月14日  査読有り
    The tumor suppressor p53 regulates multiple cellular functions, including energy metabolism. Metabolic deregulation is implicated in the pathogenesis of some cancers and in metabolic disorders and may result from the inactivation of p53 functions. Using RNA sequencing and ChIP sequencing of cancer cells and preadipocytes, we demonstrate that p53 modulates several metabolic processes via the transactivation of energy metabolism genes including dihydropyrimidinase-like 4 (DPYSL4). DPYSL4 is a member of the collapsin response mediator protein family, which is involved in cancer invasion and progression. Intriguingly, DPYSL4 overexpression in cancer cells and preadipocytes up-regulated ATP production and oxygen consumption, while DPYSL4 knockdown using siRNA or CRISPR/Cas9 down-regulated energy production. Furthermore, DPYSL4 was associated with mitochondrial supercomplexes, and deletion of its dihydropyrimidinase-like domain abolished its association and its ability to stimulate ATP production and suppress the cancer cell invasion. Mouse-xenograft and lung-metastasis models indicated that DPYSL4 expression compromised tumor growth and metastasis in vivo. Consistently, database analyses demonstrated that low DPYSL4 expression was significantly associated with poor survival of breast and ovarian cancers in accordance with its reduced expression in certain types of cancer tissues. Moreover, immunohistochemical analysis using the adipose tissue of obese patients revealed that DPYSL4 expression was positively correlated with INFg and body mass index in accordance with p53 activation. Together, these results suggest that DPYSL4 plays a key role in the tumor-suppressor function of p53 by regulating oxidative phosphorylation and the cellular energy supply via its association with mitochondrial supercomplexes, possibly linking to the pathophysiology of both cancer and obesity.
  • Ai Tamura, Tatsuki Ogasawara, Yoichi Fujii, Hiyori Kaneko, Akitoshi Nakayama, Seiichiro Higuchi, Naoko Hashimoto, Yui Miyabayashi, Masanori Fujimoto, Eri Komai, Takashi Kono, Ikki Sakuma, Hidekazu Nagano, Sawako Suzuki, Hisashi Koide, Koutaro Yokote, Kozue Iseki, Rena Oguma, Hiroyuki Matsue, Hiroyuki Nojima, Kensuke Sugiura, Hideyuki Yoshitomi, Masayuki Ohtsuka, Bahityar Rahmutulla, Atsushi Kaneda, Naoko Inoshita, Seishi Ogawa, Tomoaki Tanaka
    The Journal of clinical endocrinology and metabolism 103(7) 2417-2423 2018年7月1日  査読有り
    Context: Necrolytic migratory erythema (NME) occurs in approximately 70% of patients with glucagonoma syndrome. Excessive stimulation of metabolic pathways by hyperglucagonemia, which leads to hypoaminoacidemia, contributes to NME pathogenesis. However, the molecular pathogenesis of glucagonoma and relationships between metabolic abnormalities and clinical symptoms remain unclear. Patient: A 53-year-old woman was referred to our hospital with a generalized rash and weight loss. NME was diagnosed by histopathological examination of skin biopsy tissue. Laboratory tests revealed diabetes, hyperglucagonemia, marked insulin resistance, severe hypoaminoacidemia, ketosis, and anemia. Enhanced computed tomography scans detected a 29-mm pancreatic hypervascular tumor, which was eventually diagnosed as glucagonoma. Preoperative treatment with octreotide long-acting release reduced the glucagon level, improved the amino acid profile, and produced NME remission. Surgical tumor excision normalized the metabolic status and led to remission of symptoms, including NME. Interventions: Whole-exome sequencing (WES) and subsequent targeted capture sequencing, followed by Sanger sequencing and pyrosequencing, identified biallelic alteration of death-domain associated protein (DAXX) with a combination of loss of heterozygosity and frameshift mutations (c.553_554del:p.R185fs and c.1884dupC:p.C629fs) in the glucagonoma. Consistently, immunohistochemistry confirmed near-absence of DAXX staining in the tumor cells. Tumor expression of glucagon and somatostatin receptor subtype 2 and 3 messenger RNA was markedly upregulated. Conclusions: This is a report of glucagonoma with biallelic inactivation of DAXX determined by WES. The tumor manifested as glucagonoma syndrome with generalized NME. This case showed the relationship between hypoaminoacidemia and NME status. Further investigations are required to elucidate the underlying mechanisms of NME onset and glucagonoma tumorigenesis.
  • Hisashi Koide, Akina Shiga, Eri Komai, Azusa Yamato, Masanori Fujimoto, Ai Tamura, Takashi Kono, Akitoshi Nakayama, Tomoko Takiguchi, Seiichiro Higuchi, Ikki Sakuma, Hidekazu Nagano, Naoko Hashimoto, Sawako Suzuki, Yasuaki Takeda, Makoto Shibuya, Hiroshi Nishioka, Shozo Yamada, Naoko Inoshita, Norio Ishiwatari, Kentaro Horiguchi, Koutaro Yokote, Tomoaki Tanaka
    Internal Medicine 57(3) 367-375 2018年  査読有り
    We herein report the case of a 25-year-old woman who presented with severe headache and visual field defects after childbirth. Magnetic resonance imaging revealed marked swelling of the pituitary gland, and an endocrinological examination revealed panhypopituitarism and diabetes insipidus. An immunohistological analysis of a transsphenoidal biopsy sample of the pituitary gland showed the significant accumulation of an immunogloblin G4 (IgG4)-positive population, leading to the diagnosis of IgG4-related hypophysitis. The patient was treated with prednisolone, which markedly reduced the swelling of the pituitary gland, in association with recovery of the pituitary function. This is a rare case of biopsy-proven IgG4-related hypophysitis with a postpartum onset.
  • Masanori Hirose, Hiroyuki Takano, Hiroshi Hasegawa, Hiroyuki Tadokoro, Naoko Hashimoto, Genzo Takemura, Yoshio Kobayashi
    JOURNAL OF PHARMACOLOGICAL SCIENCES 135(4) 164-173 2017年12月  査読有り
    Dipeptidyl peptidase-4 (DPP-4) inhibitors are hypoglycemic agents. DPP-4 inhibitor has cardioprotective effects after transverse aortic constriction (TAC), but role of DPP-4 on cardiac fibrosis after TAC is not well known. Our aim was to determine the effects of DPP-4 on cardiac fibrosis in murine TAC model. Wildtype mice and DPP-4 knockout mice were subjected to TAC. Wild-type mice were then treated with vehicle or DPP-4 inhibitor. DPP-4 activities in serum and heart tissue were significantly increased at 2 weeks after TAC, but they were significantly decreased by DPP-4 inhibitor treatment. The inhibition of DPP-4 did not affect left ventricular hypertrophy, but improved cardiac function and decreased myocardial and perivascular fibrosis after TAC. The inhibition of DPP-4 decreased the collagen type III/I ratio in myocardium. These results suggest that DPP-4 inhibition ameliorates the progression of heart failure after TAC by changing the quality and quantity of cardiac fibrosis. (c) 2017 The Authors. Production and hosting by Elsevier B.V.
  • Hidekazu Nagano, Yoshinori Nakagawa, Naofumi Ishikawa, Hiroya Watanabe, Yui Miyabayashi, Akitoshi Nakayama, Masanori Fujimoto, Eri Komai, Akina Shiga, Ai Tamura, Takashi Kono, Tomoko Takiguchi, Seiichiro Higuchi, Ikki Sakuma, Naoko Hashimoto, Sawako Suzuki, Hisashi Koide, Koutaro Yokote, Tomoaki Tanaka
    ENDOCRINE PRACTICE 23(11) 1325-1332 2017年11月  査読有り
    Objective: Familial dysalbuminemic hyperthyroxinemia (FDH) is caused by abnormal human serum albumin (HSA) with an increased thyroxine (T4) affinity leading to euthyroid hyperthyroxinemia. One-and 2-step immunoassays of serum samples from FDH patients (e.g., Japanese patients) with the HSA R218P mutation can yield false-positive free thyroxine (FT4) results. Therefore, it is difficult to distinguish FDH from syndrome of inappropriate secretion of thyroid-stimulating hormone (TSH) (e.g., syndrome of resistance to thyroid hormone, TSH-producing pituitary adenoma), even when multiple assays are used. To investigate T4 to HSA binding, we examined serum samples from 7 patients from 3 Japanese families with FDH. Clinically, abnormal thyroid function tests were noted in pregnant Patient 1. Patients 2 and 3 had histories of inappropriate treatment with antithyroid drugs and surgery. Methods: All patients and affected family members were diagnosed with FDH using direct sequencing analysis. Gel filtration high-performance liquid chromatography was used for the biochemical analyses. Results: The genomic analysis revealed a heterozygous missense mutation in HSA (R218P). In FDH patient sera, the albumin effluent corresponded to the peaks for total T4 (TT4); approximately 60% of the T4 in the effluent was detected as FT4. The results for the albumin effluent from healthy volunteer and TSHoma patient sera showed no corresponding TT4 peak. Conclusion: In the FDH patients, a relatively larger quantity of T4 was bound to abnormal HSA. This bound T4 was measured as FT4 during the analysis.
  • Tomoko Takiguchi, Hisashi Koide, Hidekazu Nagano, Akitoshi Nakayama, Masanori Fujimoto, Ai Tamura, Eri Komai, Akina Shiga, Takashi Kono, Seiichiro Higuchi, Ikki Sakuma, Naoko Hashimoto, Sawako Suzuki, Yui Miyabayashi, Norio Ishiwatari, Kentaro Horiguchi, Yukio Nakatani, Koutaro Yokote, Tomoaki Tanaka
    BMC ENDOCRINE DISORDERS 17(1) 54 2017年9月  査読有り
    Background: A functional pituitary adenoma can produce multiple anterior-pituitary hormones, such as growth hormone (GH) producing adenomas (GHoma) with prolactin or thyrotropin stimulating hormone production in the same lineage. However, it is very rare that acromegaly shows subclinical Cushing's disease (SCD) beyond the lineage. Here we describe the involvement of intratumoral coexistence with 2 types of hormone-producing cells associated with different lineage in acromegaly concomitant with SCD. Case presentation: In our study, we performed clinical evaluation of the patient showing acromegaly with SCD. To elucidate the mechanisms of this pathology, we analyzed immunohistochemistry and gene expression of anterior-pituitary hormones and transcriptional factors in the resected pituitary tumor. On immunohistochemical staining, most of the tumor cells were strongly stained for GH antibody, while some cells were strongly positive for adrenocorticotropic hormone (ACTH). Gene expression analysis of a transsphenoidal surgery sample of the pituitary gland revealed that ACTH-related genes, such as POMC, Tpit, and NeuroD1 mRNA, had higher expression in the tumor tissue than the nonfunctional adenoma but lower expression compared to an adenoma of typical Cushing's disease. Further, double-labeling detection methods with a fluorescent stain for ACTH and GH demonstrated the coexistence of ACTH-positive cells (GH-negative) among the GH-positive cells in the tumor. Additionally, Pit-1 expression was reduced in the ACTH-positive cells from tumor tissue primary culture. Conclusion: Here we described a case of a pituitary tumor diagnosed with acromegaly associated with SCD. We performed quantitative-expression analyses of transcriptional factors of the tumor tissue and immunohistochemistry analysis of tumor-derived primary culture cells, which suggested that the multihormonal pituitary adenoma concomitant with Pit-1 and Tpit lineage cells caused acromegaly associated with SCD.
  • Naoko Hashimoto, Kento Ikuma, Yui Konno, Masanori Hirose, Hiroyuki Tadokoro, Hiroshi Hasegawa, Yoshio Kobayashi, Hiroyuki Takano
    JOURNAL OF PHARMACOLOGICAL SCIENCES 135(1) 29-36 2017年9月  査読有り筆頭著者
    Dipeptidyl peptidase-4 (DPP-4) inhibitors are relatively new class of anti-diabetic drugs. Some protective effects of DPP-4 on cardiovascular disease have been described independently from glucose-lowering effect. However, the detailed mechanisms by which DPP-4 inhibitors exert on endothelial cells remain elusive. The purpose of this research was to determine the effects of DPP-4 inhibitor on endothelial barrier function. Human umbilical vein endothelial cells (HUVECs) were cultured and exposed to hypoxia in the presence or absence of Diprotin A, a DPP-4 inhibitor. Immunocytochemistry of vascular endothelial (VE-) cadherin showed that jagged VE-cadherin staining pattern induced by hypoxia was restored by treatment with Diprotin A. The increased level of cleaved beta-catenin in response to hypoxia was significantly attenuated by Diprotin A, suggesting that DPP-4 inhibition protects endothelial adherens junctions from hypoxia. Subsequently, we found that Diprotin A inhibited hypoxia-induced translocation of NF-kappa B from cytoplasm to nucleus through decreasing TNF-alpha expression level. Furthermore, the tube formation assay showed that Diprotin A significantly restored hypoxia-induced decrease in number of tubes by HUVECs. These results suggest that DPP-4 inhibitior protects HUVECs from hypoxia-induced barrier impairment. (C) 2017 The Authors. Production and hosting by Elsevier B.V. on behalf of Japanese Pharmacological Society.

MISC

 315

講演・口頭発表等

 350

共同研究・競争的資金等の研究課題

 9