TY - JOUR
T1 - Major involvement of Na+-dependent multivitamin transporter (SLC5A6/SMVT) in uptake of biotin and pantothenic acid by human brain capillary endothelial cells
AU - Uchida, Yasuo
AU - Ito, Katsuaki
AU - Ohtsuki, Sumio
AU - Kubo, Yoshiyuki
AU - Suzuki, Takashi
AU - Terasaki, Tetsuya
N1 - Publisher Copyright:
© 2015 International Society for Neurochemistry.
PY - 2015/7/1
Y1 - 2015/7/1
N2 - The purpose of this study was to clarify the expression of Na+-dependent multivitamin transporter (SLC5A6/SMVT) and its contribution to the supply of biotin and pantothenic acid to the human brain via the blood-brain barrier. DNA microarray and immunohistochemical analyses confirmed that SLC5A6 is expressed in microvessels of human brain. The absolute expression levels of SLC5A6 protein in isolated human and monkey brain microvessels were 1.19 and 0.597 fmol/μg protein, respectively, as determined by a quantitative targeted absolute proteomics technique. Using an antibody-free method established by Kubo et al. (2015), we found that SLC5A6 was preferentially localized at the luminal membrane of brain capillary endothelium. Knock-down analysis using SLC5A6 siRNA showed that SLC5A6 accounts for 88.7% and 98.6% of total [3H]biotin and [3H]pantothenic acid uptakes, respectively, by human cerebral microvascular endothelial cell line hCMEC/D3. SLC5A6-mediated transport in hCMEC/D3 was markedly inhibited not only by biotin and pantothenic acid, but also by prostaglandin E2, lipoic acid, docosahexaenoic acid, indomethacin, ketoprofen, diclofenac, ibuprofen, phenylbutazone, and flurbiprofen. This study is the first to confirm expression of SLC5A6 in human brain microvessels and to provide evidence that SLC5A6 is a major contributor to luminal uptake of biotin and pantothenic acid at the human blood-brain barrier.
AB - The purpose of this study was to clarify the expression of Na+-dependent multivitamin transporter (SLC5A6/SMVT) and its contribution to the supply of biotin and pantothenic acid to the human brain via the blood-brain barrier. DNA microarray and immunohistochemical analyses confirmed that SLC5A6 is expressed in microvessels of human brain. The absolute expression levels of SLC5A6 protein in isolated human and monkey brain microvessels were 1.19 and 0.597 fmol/μg protein, respectively, as determined by a quantitative targeted absolute proteomics technique. Using an antibody-free method established by Kubo et al. (2015), we found that SLC5A6 was preferentially localized at the luminal membrane of brain capillary endothelium. Knock-down analysis using SLC5A6 siRNA showed that SLC5A6 accounts for 88.7% and 98.6% of total [3H]biotin and [3H]pantothenic acid uptakes, respectively, by human cerebral microvascular endothelial cell line hCMEC/D3. SLC5A6-mediated transport in hCMEC/D3 was markedly inhibited not only by biotin and pantothenic acid, but also by prostaglandin E2, lipoic acid, docosahexaenoic acid, indomethacin, ketoprofen, diclofenac, ibuprofen, phenylbutazone, and flurbiprofen. This study is the first to confirm expression of SLC5A6 in human brain microvessels and to provide evidence that SLC5A6 is a major contributor to luminal uptake of biotin and pantothenic acid at the human blood-brain barrier.
KW - SLC5A6
KW - biotin
KW - human blood-brain barrier
KW - luminal uptake
KW - pantothenic acid
KW - structure of inhibitor
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U2 - 10.1111/jnc.13092
DO - 10.1111/jnc.13092
M3 - Article
C2 - 25809983
AN - SCOPUS:84935891582
VL - 134
SP - 97
EP - 112
JO - Journal of Neurochemistry
JF - Journal of Neurochemistry
SN - 0022-3042
IS - 1
ER -