Dynamic Gut Microbiome Changes in Response to Low-Iron Challenge.

Area of Science:

• Microbiome research
• Nutritional science
• Mammalian physiology

Background:

• Iron is vital for all cells, and its dysregulation contributes to disease.
• Dietary iron absorption occurs mainly in the small intestine.
• The gut microbiome's response to dietary iron levels is not well understood.

Purpose of the Study:

• To investigate the impact of dietary iron on gut microbiome structure and function.
• To establish a mouse model for studying low-iron challenges.
• To identify specific bacterial taxa sensitive to iron deficiency.

Main Methods:

• A low-iron diet challenge was implemented in C57BL/6 mice.
• Intestinal and fecal biomarkers were monitored for iron stress.
• Serum iron and behavioral markers assessed host iron homeostasis.
• Microbiome taxonomic structure was analyzed using operational taxonomic units (OTUs).

Main Results:

• Low-iron diet dramatically altered gut microbiome diversity within two weeks.
• Microbiome changes persisted long-term, with poor recovery after iron reintroduction.
• Specific bacterial groups, including Prevotellaceae, Porphyromonadaceae, and Bacteroidales, were highly sensitive to low iron.
• Some OTUs appeared to be extirpated from the gut entirely.

Conclusions:

• Dietary iron levels critically influence gut microbiome composition.
• Certain gut bacteria exhibit significant iron sensitivity, leading to potential loss.
• This study identifies key bacterial taxa affected by dietary iron, advancing understanding of mammalian iron cycling.