Skin aging and phosphate

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K17325
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 53050:Dermatology-related
• Research Institution: Jichi Medical University
• Principal Investigator: Kamiya Koji 自治医科大学, 医学部, 准教授 (90790668)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 皮膚老化 / Klotho欠損マウス / 17型コラーゲン

Outline of Final Research Achievements

The klotho mouse shows multiple phenotypes resembling human aging caused by a defect in klotho gene expression. In the homozygous mutant klotho mice (KL-/-), epidermal and dermal atrophy and hair loss were observed by histopathological analysis. Calciprotein particles were not detected in the skin by von Kossa staining. Immunofluorescence showed the decreased level of type 17 collagen in the epidermal stem cells and type 5 collagen in the papillary dermis. The relative mRNA expression of matrixmetalloproteinase 9, a disintegrin and metalloproteinase 9 (ADAM9), ADAM10, and tissue inhibitor of metalloproteinase 1 was decreased by quantitative PCR. The relative mRNA expression of epidermal growth factor receptor was not decreased, while that of heparin-binding epidermal growth factor-like growth factor and transforming growth factor-α was decreased. Immunofluorescence showed that the expression level of type 17 collagen was maintained in KL-/- mice fed by low phosphate diet.

Free Research Field

皮膚老化

Academic Significance and Societal Importance of the Research Achievements

ミネラル代謝異常などの内因性ストレスによる皮膚老化の病態は未解明で、これまで皮膚老化に対する有効な治療法はない。本研究では、老化モデルマウスを用いて、体内リン貯留による表皮幹細胞における17型コラーゲンの発現低下を確認した。また、体内リン貯留を抑えることで、表皮幹細胞における17型コラーゲンの発現が維持されることを確認した。ヒトの皮膚老化でも同様の病態が明らかになれば、新たな治療法の開発につながる。