Exploring Molecular Interactions between Human Milk Hormone Insulin and Bifidobacteria

Area of Science:

• Microbiology
• Endocrinology
• Human Biology

Background:

• Breast milk composition is optimized by evolution for infant nutrition and protection.
• Hormones in breast milk, like insulin, are bioactive compounds influencing the infant gut microbiota.
• Gestational diabetes mellitus (GDM) affects pregnant women and may alter insulin levels in breast milk.

Purpose of the Study:

• To explore molecular interactions between human milk insulin and bifidobacterial strains.
• To investigate how insulin affects the infant gut microbiota composition.
• To understand the role of insulin in early gut microbiota assembly.

Main Methods:

• Analysis of 3,620 public metagenomic datasets to correlate bifidobacterial communities with milk insulin levels.
• In vitro gut microbiota model to assess molecular interactions between insulin and bifidobacteria.
• Omics approaches to identify bacterial genes involved in adaptation and colonization.

Main Results:

• Bifidobacterial communities in the infant gut vary with breast milk insulin concentrations.
• Insulin appears to enhance the persistence of Bifidobacterium bifidum in the infant gut.
• Identified bacterial genes associated with cell adaptation and colonization in response to insulin.

Conclusions:

• Human milk insulin is a significant factor modulating the infant gut microbiota.
• Insulin influences the gut microbial community structure, favoring specific bifidobacterial taxa.
• This study elucidates a molecular crosstalk between a breast milk hormone and infant gut bacteria, impacting microbiota assembly.