A Switch in Iron Delivery Is Critical for Postnatal Kidney Development

Area of Science:

• Developmental Biology
• Iron Metabolism
• Renal Physiology

Background:

• Periconceptual maternal iron deficiency (FeD) is a global cause of adverse pregnancy outcomes.
• The differential impact of FeD on developing tissues and the roles of specific iron species (transferrin-bound vs. non-transferrin-bound iron - NTBI) in organogenesis remain unclear.

Purpose of the Study:

• To investigate the role of transferrin receptor 1 (TfR1) in kidney development.
• To differentiate the contributions of transferrin-bound and NTBI to embryonic kidney organogenesis.
• To explore the reversibility of iron deficiency-induced kidney disease.

Main Methods:

• Generated TfR1-deficient mice and cell lines.
• Utilized global iron deficiency models via iron-poor diets.
• Examined cell-autonomous TfR1 deletions in specific kidney cell lineages.
• Assessed kidney development at mid-gestation and postnatal stages.

Main Results:

• TfR1 deletion alone had minimal impact on embryonic kidney development.
• Nutritional iron deficiency severely impaired kidney development.
• Postnatal TfR1 function became critical, with its absence leading to polycystic kidney disease.
• Iron supplementation reversed kidney malformations and restored function.

Conclusions:

• TfR1 is essential for postnatal kidney tubulogenesis.
• Alternative iron species (NTBI) are crucial for embryonic kidney development, complementing TfR1.
• Iron deficiency-induced kidney disease is reversible with postnatal iron treatment.