Impact of SLC6A Transporters in Physiological Taurine Transport at the Blood–Retinal Barrier and in the Liver

• Kubo Yoshiyuki

  Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama

• Akanuma Shin-ichi

  Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama

• Hosoya Ken-ichi

  Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama

Abstract

Cumulative studies showed that taurine (2-aminoethanesulfonic acid) contributes to a variety of physiological events. Transport study suggested the cellular taurine transport in an Na⁺- and Cl⁻-dependent manner, and the several members of SLC6A family have been shown as taurine transporter. At the inner blood–retinal barrier (BRB), taurine transporter (TauT/SLC6A) is involved in the transport of taurine to the retina from the circulating blood. The involvement of TauT is also suggested in γ-aminobutyric acid (GABA) transport at the inner BRB, and its role is assumed in the elimination of GABA from the retinal interstitial fluid. In the retina, taurine is thought to be a major organic osmolyte, and its influx and efflux through TauT and volume-sensitive organic osmolyte and anion channel (VSOAC) in Müller cells regulate the osmolarity in the retinal microenvironment to maintain a healthy retina. In the liver, hepatocytes take up taurine via GABA transporter 2 (GAT2/SLC6A13, the orthologue of mouse GAT3) expressed at the sinusoidal membrane of periportal hepatocytes, contributing to the metabolism of bile acid. Site-directed mutagenesis study suggests amino acid residues that are crucial in the recognition of substrates by GATs and TauT. The evidence suggests the physiological impact of taurine transporters in tissues.

Journal

• Biological and Pharmaceutical Bulletin

  Biological and Pharmaceutical Bulletin 39 (12), 1903-1911, 2016

  The Pharmaceutical Society of Japan

Keywords

• SLC6A family
• taurine transporter
• γ-aminobutyric acid transporter
• blood–retinal barrier
• liver

Details

• CRID: 1390001204633840768
• NII Article ID: 130005171493
• NII Book ID: AA10885497
• DOI: 10.1248/bpb.b16-00597
• ISSN: 13475215
• ISSN: 09186158
• NDL BIB ID: 027752343
• PubMed: 27904033
• Web Site: http://id.ndl.go.jp/bib/027752343
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I027752343
• Web Site: https://www.jstage.jst.go.jp/article/bpb/39/12/39_b16-00597/_pdf
• Web Site: https://search.jamas.or.jp/link/ui/2017193317
• Text Lang: en
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • PubMed
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed