Analysis of parathyroid hormone producing cells in adipose tissues surrounding hyperplasia parathyroid glands

Research Project

Project/Area Number	18K16009
Research Category	Grant-in-Aid for Early-Career Scientists
Allocation Type	Multi-year Fund
Review Section	Basic Section 53040:Nephrology-related
Research Institution	Tokai University
Principal Investigator	TATSUMI Ryoko 東海大学, 医学部, 助教 (60631819)
Project Period (FY)	2018-04-01 – 2020-03-31
Project Status	Completed (Fiscal Year 2019)
Budget Amount *help	¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000) Fiscal Year 2019: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000) Fiscal Year 2018: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
Keywords	二次性副甲状腺機能亢進症 / 副甲状腺ホルモン / 脂肪分化 / 異所的PTH産生細胞
Outline of Final Research Achievements	I investigated hyperplasia parathyroid glands and the neighboring organs which were removed from patients with secondary hyperparathyroidism and found the colony of the ectopic parathyroid hormone (PTH) -producing cell which lay scattered in adipose tissue which surrounded the parathyroid gland in 23 of 31 (74.2%) patients. After transplanting the piece of the human parathyroid gland under the thyroid gland of the renal failure immunodeficiency rat to clarify origins of the ectopic PTH-producing cell and adipose tissue, it detected expression of differentiation marker PPARγ and Perilipin of the adipose cell in grafts 1-3 months later. The parathyroid gland cell was available for the transdifferentiation to a adipose cell, and it was thought that the adipose tissue which accumulated around parathyroid glands came from a parathyroid cells pushed out from glands.
Academic Significance and Societal Importance of the Research Achievements	二次性副甲状腺機能亢進症（SHPT）は慢性腎不全の過程で進行する血中のカルシウムやリン、ビタミンDの濃度調整不良に反応した適応症として発症し、副甲状腺細胞の増殖と過形成、副甲状腺ホルモンの過剰な産生と分泌を特徴とする。進行したSHPTは高カルシウム血症や高リン血症を促進させ、異所性石灰化や血管硬化症などを誘発して透析患者の予後に関わるが、SHPTの発症と進行については不明な点が多い。本研究はSHPTの発症と進行を周辺組織を含めて総合的に理解するために、過形成副甲状腺への脂肪蓄積のメカニズムについて調査する。その成果により高い有効性を持つ新たな治療法の開発基盤を提供することが期待される。