Elucidation of the role of the ubiquitin ligase KLHL3 in the pathogenesis of diabetic kidney disease

• Project/Area Number: 19K17719
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 53040:Nephrology-related
• Research Institution: Teikyo University
• Principal Investigator: Ishizawa Kenichi 帝京大学, 医学部, 講師 (10772684)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥3,380,000 (Direct Cost: ¥2,600,000、Indirect Cost: ¥780,000); Fiscal Year 2020: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000); Fiscal Year 2019: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
• Keywords: KLHL3 / リン酸化 / 糖尿病 / 糖尿病性腎症 / 高血圧 / NKCC2

Outline of Research at the Start

糖尿病性腎臓病は末期腎不全の主要な原疾患だが、有効な治療法は確立されていない。本研究では、アンジオテンシンIIの新規エフェクターとして同定されたユビキチンリガーゼ構成分子Kelch-like 3（KLHL3）による機能異常に焦点をあて、糖尿病性腎臓病における役割を尿細管構成細胞および免疫細胞を中心に解析する。また本研究で得られた知見を臨床へと展開するため、糖尿病性腎臓病を含む各種腎臓病の腎生検検体を用いたKLHL3活性の変化についても解析を計画する。本研究により糖尿病性腎症におけるKLHL3の病的役割が明らかとなれば、新たな治療標的分子の同定も期待できる。

Outline of Final Research Achievements

In this study, we focused on the phosphorylation of the ubiquitin ligase component Kelch-like 3 (KLHL3), a novel effector of angiotensin II, and analyzed its relationship with diabetic kidney disease. In addition to the distal tubules of diabetic model mice (db/db), KLHL3-Ser433 phosphorylation signals are also observed in the thick ascending limb (TAL) of Henle's loop, and the expression of NKCC2 expressed at the same site is also upregulated. We also investigated the existence of phosphorylated KLHL3 in humans and detected phosphorylated KLHL3 in human renal biopsy specimens and urine exosome fractions.

Academic Significance and Societal Importance of the Research Achievements

本研究では、糖尿病性腎臓病におけるKLHL3リン酸化の病的役割について検討し、病態の一端を解明した。また、ヒトにおいて腎臓と尿exosome分画でKLHL3リン酸化を検出したため、今後の臨床応用が期待できる。

Research Products

• [Journal Article] Characterization of pendrin in urinary extracellular vesicles in a rat model of aldosterone excess and in human primary aldosteronism. (2021)
  • Author(s): Ochiai-Homma F, Kuribayashi-Okuma E, Tsurutani Y, Ishizawa K, Fujii W, Odajima K, Kawagoe M, Tomomitsu Y, Murakawa M, Asakawa S, Hirohama D, Nagura M, Arai S, Yamazaki O, Tamura Y, Fujigaki Y, Nishikawa T, Shibata S
  • Journal Title: Hypertens Res Volume: 44 Issue: 12 Pages: 1557-1567
  • DOI: 10.1038/s41440-021-00710-5
  • Peer Reviewed / Open Access
• [Journal Article] Urinary phosphate-containing nanoparticle contributes to inflammation and kidney injury in a salt-sensitive hypertension rat model (2020)
  • Author(s): Wang Qin、Ishizawa Kenichi、Li Jinping、Fujii Wataru、Nemoto Yoshikazu、Yamazaki Osamu、Tamura Yoshifuru、Miura Yutaka、Nie Xuedan、Abe Ryo、Segawa Hiroko、Kuro-O Makoto、Shibata Shigeru
  • Journal Title: Communications Biology Volume: 3 Issue: 1 Pages: 575-575
  • DOI: 10.1038/s42003-020-01298-1
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Upregulation of renal Na/K/2Cl cotransporter 2 in obese diabetes mellitus via a vasopressin receptor 2-dependent pathway (2020)
  • Author(s): Sakai Kazuhiro、Yamazaki Osamu、Ishizawa Kenichi、Tamura Yoshifuru、Wang Qin、Ueno Masaki、Hayama Yuto、Fujigaki Yoshihide、Shibata Shigeru
  • Journal Title: Biochemical and Biophysical Research Communications Volume: 524 Issue: 3 Pages: 710-715
  • DOI: 10.1016/j.bbrc.2020.01.142
  • Peer Reviewed
• [Journal Article] Role of the Ubiquitin Proteasome System in the Regulation of Blood Pressure: A Review (2020)
  • Author(s): Yamazaki Osamu、Hirohama Daigoro、Ishizawa Kenichi、Shibata Shigeru
  • Journal Title: International Journal of Molecular Sciences Volume: 21 Issue: 15 Pages: 5358-5358
  • DOI: 10.3390/ijms21155358
  • Peer Reviewed / Open Access
• [Journal Article] Inhibition of Sodium Glucose Cotransporter 2 Attenuates the Dysregulation of Kelch-Like 3 and NaCl Cotransporter in Obese Diabetic Mice (2019)
  • Author(s): Ishizawa Kenichi、Wang Qin、Li Jinping、Xu Ning、Nemoto Yoshikazu、Morimoto Chikayuki、Fujii Wataru、Tamura Yoshifuru、Fujigaki Yoshihide、Tsukamoto Kazuhisa、Fujita Toshiro、Uchida Shunya、Shibata Shigeru
  • Journal Title: Journal of the American Society of Nephrology Volume: － Issue: 5 Pages: 782-794
  • DOI: 10.1681/asn.2018070703
  • Peer Reviewed / Open Access
• [Presentation] Creation and characterization of the ubiquitin ligase KLHL3-S433A knock-in mice (2022)
  • Author(s): Kenichi Ishizawa, Ken Kaseda, Osamu Yamazaki, Shigeru Shibata
  • Organizer: The 29th Scientific Meeting of the International Society of Hypertension
  • Int'l Joint Research
• [Presentation] ヒト尿中exosome分画と腎免疫染色におけるユビキチンリガーゼKLHL3リン酸化の検討 (2022)
  • Author(s): 石澤 健一 , 山崎 修 , 田村 好古 , 藤垣 嘉秀 , 鶴谷 悠也 , 西川 哲男 , 柴田 茂
  • Organizer: 第65回 日本腎臓学会学術総会