Role of hepcidin in iron metabolism in calves: regulatory expression of hepcidin

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K08044
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Animal production science
• Research Institution: Kyoto University
• Principal Investigator: Funaba Masayuki 京都大学, 農学研究科, 准教授 (40238655)
• Co-Investigator(Kenkyū-buntansha): 松井 徹 京都大学, 農学研究科, 教授 (40181680)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 畜産学 / 栄養学 / シグナル伝達

Outline of Final Research Achievements

Hepcidin is a liver-derived hormone that regulates plasma iron level negatively. The present study explored relationship between systemic iron status and bovine hepcidin. The levels of plasma iron, blood hemoglobin and hematocrit were lower in calves aged 1-4 weeks, and increased thereafter. In contrast, plasma levels of hepcidin and ferritin were relatively constant in calves, except for newborn calves that showed higher hepcidin and ferritin levels. Previous studies reveal that iron overload stimulates murine and human hepcidin transcription that is mediated by Smad1/Smad4 through induction of BMP6 gene. The present study revealed that transcriptional activity of bovine Smad4 was lower than that of murine Smad4, which could not be explained by differences of amino acid sequence between bovine Smad4 and murine Smad4.

Free Research Field

家畜栄養学

Academic Significance and Societal Importance of the Research Achievements

鉄恒常性は健康を維持する上で重要である。ヘプシジンは血中鉄濃度を負に制御する上で中心的に働くホルモンである。黒毛和種子牛は1週齢から4週齢まで貧血状態であったが、これはヘプシジンの過剰分泌が原因ではなかった。マウスやヒトでは鉄負荷によるヘプシジン転写はSmad1/Smad4を介して起こることが知られているが、ウシSmad4のヘプシジン転写能はマウスSmad4よりも低いこと、この原因として、両者のアミノ酸配列の相違では説明できないことが明らかになった。これらの基礎知見は、より健康な子牛飼養法の開発に寄与し得る。