ヒグチ　ケイ   Higuchi Kei   樋口　慧    所属   東邦大学  薬学部 薬学科    職種   准教授
論文種別	原著
言語種別	英語
査読の有無	査読あり
表題	Transport Mechanisms for the Nutritional Supplement β-Hydroxy-β-Methylbutyrate (HMB) in Mammalian Cells.
掲載誌名	正式名：Pharmaceutical research
掲載区分	国外
巻・号・頁	36(6),pp.84-84
著者・共著者	Jiro Ogura,Toshihiro Sato,Kei Higuchi,Yangzom D Bhutia,Ellappan Babu,Masayuki Masuda,Seiji Miyauchi,Ricardo Rueda,Suzette L Pereira,Vadivel Ganapathy
発行年月	2019/04/17
概要	PURPOSE: β-Hydroxy-β-methylbutyrate (HMB), a nutritional supplement, elicits anabolic activity in muscle. Here we investigated the mechanism of HMB uptake in muscle cells. METHODS: Murine muscle cells (C2C12) and human mammary epithelial cells (MCF7) were used for uptake. As HMB is a monocarboxylate, focus was on monocarboxylate transporters, monitoring interaction of HMB with H+-coupled lactate uptake, and influence of H+ directly on HMB uptake. Involvement of MCT1-4 was studied using selective inhibitors and gene silencing. Involvement of human Na+/monocarboxylate transporter SMCT1 was also assessed using Xenopus oocytes. RESULTS: H+-coupled lactate uptake was inhibited by HMB in both mammalian cells. HMB uptake was H+-coupled and inhibited by lactate. C2C12 cells expressed MCT1 and MCT4; MCF7 cells expressed MCT1-4; undifferentiated C2C12 cells expressed SMCT1. SMCT1 mediated Na+-coupled HMB transport. Inhibitors of MCT1/4, siRNA-mediated gene silencing, and expression pattern showed that MCT1-4 were responsible only for a small portion of HMB uptake in these cells. CONCLUSION: HMB uptake in C2C12 and MCF7 cells is primarily H+-coupled and inhibited by lactate, but MCT1-4 are only partly responsible for HMB uptake. SMCT1 also transports HMB, but in a Na+-coupled manner. Other, yet unidentified, transporters mediate the major portion of HMB uptake in C2C12 and MCF7 cells.
DOI	10.1007/s11095-019-2626-3
PMID	30997560