Effects of insulin-like growth factor-1 and vitamin D on age-related olfactory dysfunction

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K09841
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 56050:Otorhinolaryngology-related
• Research Institution: The University of Tokyo
• Principal Investigator: Ueha Rumi 東京大学, 医学部附属病院, 准教授 (10597131)
• Co-Investigator(Kenkyū-buntansha): 上羽 悟史 東京理科大学, 研究推進機構生命医科学研究所, 准教授 (00447385) ; 近藤 健二 東京大学, 医学部附属病院, 教授 (40334370)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: 嗅覚障害 / 加齢 / IGF-1 / Vit D / 嗅神経上皮

Outline of Final Research Achievements

Administering low doses of IGF-1 has demonstrated effectiveness in reducing age-related olfactory nerve cell damage. Long-term administration showed no adverse effects on the hematopoietic and immune systems in the bone marrow, spleen, and thymus, ensuring the safety of low-dose IGF-1. However, the effectiveness of IGF-1 in reducing olfactory epithelium damage differs depending on its concentration, and further research is needed to determine the optimal dose and administration schedule. Conversely, Vitamin D had neither a positive nor negative impact on the olfactory nerve cell system.
It is thought that IGF-1 administration alleviates age-related damage to the olfactory nerve cell system by reducing inflammatory cytokines and enhancing the extracellular matrix. Conversely, Vitamin D does not appear to have a promising therapeutic effect on olfactory impairment.

Free Research Field

耳鼻咽喉科

Academic Significance and Societal Importance of the Research Achievements

現在治療方法のない加齢性嗅覚障害への新規治療へのターゲットとしてIGF-1が重要であることが明らかになった．一方、加齢性嗅覚障害へのビタミンDの経口摂取による効果は認められなかった。今後IGF-1による嗅覚障害への臨床応用に向けた研究が必要である.