ArticleThe Journal of physiology2009
The SNAT4 isoform of the system A amino acid transporter is functional in human placental microvillous plasma membrane.
Article in The Journal of physiology, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 33 papers, 1 of them a synthesis that pooled it.
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Who cites it
33 citing papers in PubMed, 1 synthesis or guideline pooled it, 84 citations in OpenAlex.
- Placental expression and activity of system A and system L amino acid transporters in pregnancies complicated by diabetes mellitus and fetal growth disorders: a systematic review.Frontiers in endocrinology · 2026Pooled it
- The SLC-ome of membrane transport: from molecular discovery to physiology and clinical applications.Physiological reviews · 2026Review
- Comparative Impact of Alternate-Day Fasting and Time-Restricted Feeding on Placental Function and Fetal Development in Maternal Obesity.Nutrients · 2024Article
- Regulation of placental amino acid transport in health and disease.Acta physiologica (Oxford, England) · 2024Review
- Assessment of Placental Sodium-Independent Leucine Uptake and Transfer in Trophoblast Cells.Methods in molecular biology (Clifton, N.J.) · 2024Article
- The impact of early pregnancy metabolic disorders on pregnancy outcome and the specific mechanism.European journal of medical research · 2023Review
- Human Placental Adaptive Changes in Response to Maternal Obesity: Sex Specificities.International journal of molecular sciences · 2023Review
- Placenta-specific Slc38a2/SNAT2 knockdown causes fetal growth restriction in mice.Clinical science (London, England : 1979) · 2021Article
- Human placental uptake of glutamine and glutamate is reduced in fetal growth restriction.Scientific reports · 2020Article
- L-carnitine increases cell proliferation and amino acid transporter expression via the activation of insulin-like growth factor I signaling pathway in rat trophoblast cells.Food science & nutrition · 2020Article
- Amino Acids and Developmental Origins of Hypertension.Nutrients · 2020Review
- A systems perspective on placental amino acid transport.The Journal of physiology · 2018Review
- Article
- Placental dysfunction is associated with altered microRNA expression in pregnant women with low folate status.Molecular nutrition & food research · 2017Article
- siRNA Transfection and EMSA Analyses on Freshly Isolated Human Villous Cytotrophoblasts.Journal of visualized experiments : JoVE · 2016Article
- Blastomere removal from cleavage-stage mouse embryos alters placental function, which is associated with placental oxidative stress and inflammation.Scientific reports · 2016Article
- Developmental origins of metabolic disorders: The need for biomarker candidates and therapeutic targets from adequate preclinical models.EuPA open proteomics · 2016Article
- TNF-α stimulates System A amino acid transport in primary human trophoblast cells mediated by p38 MAPK signaling.Physiological reports · 2015Article
- Maternal-fetal nutrient transport in pregnancy pathologies: the role of the placenta.International journal of molecular sciences · 2014Review
- The SLC38 family of sodium-amino acid co-transporters.Pflugers Archiv : European journal of physiology · 2014Review
Corrections and comments
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Authors and funding
7 authors at 1 institution in 1 country.
Funding
Abstract
Placental system A activity is important for the supply of neutral amino acids needed for fetal growth. There are three system A isoforms: SNAT1, SNAT2 and SNAT4, but the contribution of each to system A-mediated transport is unknown. Here, we have used immunohistochemistry to demonstrate that all three isoforms are present in the syncytiotrophoblast suggesting each plays a role in amino acid transport across the placenta. We next tested the hypothesis that the SNAT4 isoform is functional in microvillous plasma membrane vesicles (MVM) from normal human placenta using a method which exploits the unique property of SNAT4 to transport both cationic amino acids as well as the system A-specific substrate MeAIB. The data show that SNAT4 contribution to system A-specific amino acid transport across MVM is higher in first trimester placenta compared to term (approx. 70% and 33%, respectively, P < 0.01). Further experiments performed under more physiological conditions using intact placental villous fragments suggest a contribution of SNAT4 to system A activity in first trimester placenta but minimal contribution at term. In agreement, Western blotting revealed that SNAT4 protein expression is higher in first trimester MVM compared to term (P < 0.05). This study provides the first evidence of SNAT4 activity in human placenta and demonstrates the contribution of SNAT4 to system A-mediated transport decreases between first trimester and term: our data lead us to speculate that at later stages of gestation SNAT1 and/or SNAT2 are more important for the supply of amino acids required for normal fetal growth.
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Registered trials
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