Clinical Report: Expression and Function of Amino Acid Transporters in Placenta

Overview

This systematic review evaluates the expression and activity of System A and System L amino acid transporters in placentas from pregnancies complicated by diabetes and fetal growth disorders. Findings indicate that fetal growth restriction is associated with downregulation of these transporters, while diabetes leads to their upregulation.

Background

Fetal growth disorders, including fetal growth restriction (FGR) and macrosomia, are linked to increased neonatal morbidity and long-term health issues. The placenta plays a critical role in nutrient transfer, particularly amino acids, which are vital for fetal development.

Data Highlights

No numerical data or trial data was provided in the source material.

Key Findings

• FGR and small-for-gestational age (SGA) fetuses show significant downregulation of System A and L activity.
• Pregnancies complicated by diabetes exhibit upregulated transport capacity of amino acids.
• Increased expression of SNAT1 and LAT1 isoforms correlates with higher neonatal birth weight and adiposity.
• Time-dependent variations in transporter expression are noted, particularly the downregulation of SNAT4 in early-onset FGR.
• Alterations in amino acid transporter activity may influence fetal growth trajectory and body composition.

Clinical Implications

The findings highlight the expression of amino acid transporters in the placenta in pregnancies complicated by diabetes and fetal growth disorders.

Conclusion

The review highlights the adaptive changes in placental amino acid transport capacity in response to maternal metabolic conditions.

Related Resources & Content

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21. Frontiers | 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