ABCG5 and ABCG8 Are Involved in Vitamin K Transport
| Autor: | Michinori Matsuo, Yutaka Ogata, Yoshihide Yamanashi, Tappei Takada |
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| Rok vydání: | 2023 |
| Předmět: | |
| Zdroj: | Nutrients Volume 15 Issue 4 Pages: 998 |
| ISSN: | 2072-6643 |
| DOI: | 10.3390/nu15040998 |
| Popis: | ATP-binding cassette protein G5 (ABCG5)/ABCG8 heterodimer exports cholesterol from cells, while Niemann–Pick C1-like 1 (NPC1L1) imports cholesterol and vitamin K. We examined whether ABCG5/ABCG8 transports vitamin K similar to NPC1L1. Since high concentrations of vitamin K3 show cytotoxicity, the cytoprotective effects of ABCG5/ABCG8 were examined. BHK cells expressing ABCG5/ABCG8 were more resistant to vitamin K3 cytotoxicity than control cells, suggesting that ABCG5/ABCG8 transports vitamin K3 out of cells. The addition of vitamin K1 reversed the effects of ABCG5/ABCG8, suggesting that vitamin K1 competitively inhibits the transport of vitamin K3. To examine the transport of vitamin K1 by ABCG5/ABCG8, vitamin K1 levels in the medium and cells were measured. Vitamin K1 levels in cells expressing ABCG5/ABCG8 were lower than those in control cells, while vitamin K1 efflux increased in cells expressing ABCG5/ABCG8. Furthermore, the biliary vitamin K1 concentration in Abcg5/Abcg8-deficient mice was lower than that in wild-type mice, although serum vitamin K1 levels were not affected by the presence of Abcg5/Abcg8. These findings suggest that ABCG5 and ABCG8 are involved in the transport of sterols and vitamin K. ABCG5/ABCG8 and NPC1L1 might play important roles in the regulation of vitamin K absorption and excretion. |
| Databáze: | OpenAIRE |
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