Analysis of mechanism of adipose differentiation around hyperplastic parathyroids

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K08237
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 53040:Nephrology-related
• Research Institution: Tokai University
• Principal Investigator: KAKUTA TAKATOSHI 東海大学, 医学部, 教授 (50276854)
• Co-Investigator(Kenkyū-buntansha): 金井 厳太 東海大学, 医学部, 講師 (00535221) ; 澤田 佳一郎 東海大学, 医学部, 客員講師 (10420952)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 二次性副甲状腺機能亢進症

Outline of Final Research Achievements

Hyperplasia of the parathyroid glands caused by secondary hyperparathyroidism leads to the accumulation of large amounts of fat around the glands, which causes inflammation and other problems that lead to a poor prognosis. The origin of this fat and the mechanism of its accumulation were largely unknown, but we found that many parathyroid hormone-producing cell colonies are scattered in the adipose tissue attached to the gland. This suggests that the cells in the nodules and diffuse areas that were pushed out of the membrane may have differentiated into adipocytes during the process of hyperplasia, when a single large nodule eventually occupied the entire gland and formed a thick capsule around the nodule. In fact, when a small piece of excised human parathyroid gland was transplanted into the thyroid gland of immunodeficient rats, the graft differentiated into adipocytes, supporting this hypothesis.

Free Research Field

腎臓内科学

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(PTH)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、透析患者の予後に関わる異所性石灰化や血管硬化症を誘発する。また、腺の周囲に大量の脂肪を蓄積して炎症等を引き起こし予後不良の原因となる。本研究では、これまでほとんど知られていなかった、過形成腺周囲の脂肪組織の由来や蓄積の機序を検討した。その成果は、SHPTの発症の予防や治療に寄与すると考えられる。