Summary: A mouse study shows that the probiotic Bifidobacterium breve given to mothers during pregnancy can influence fetal brain development by enhancing nutrient transport and cellular growth pathways. These results point to the maternal gut microbiome as a potential non-pharmaceutical target for supporting healthy fetal growth, though human studies are required to confirm the effects and safety.
Researchers compared fetal brain development in three groups of mice: mothers with no gut bacteria (germ-free), mothers colonized only with Bifidobacterium breve during pregnancy, and conventionally colonized controls. Fetuses of mothers that received B. breve showed increased nutrient transport to the brain and changes in metabolic and growth-related cellular processes, suggesting a beneficial influence on fetal brain metabolism and development.
Key facts:
- Maternal colonization with Bifidobacterium breve enhanced transport mechanisms for glucose and certain amino acids into the fetal brain.
- Probiotic supplementation could offer a non-pharmacological approach to support fetal growth and brain development, particularly in pregnancies at risk for fetal growth restriction.
- Further research is needed to determine whether these findings translate to human pregnancy and how B. breve interacts with the wider maternal gut microbiome.
Source: University of Cambridge
Study overview
In this controlled experimental study, germ-free pregnant mice were colonized with the probiotic strain Bifidobacterium breve UCC2003 during gestation. The researchers then analyzed metabolic profiles in fetal brains, measured transporter abundance, and assessed expression of signaling pathways linked to metabolism, growth and neural development.
Bifidobacterium breve is a naturally occurring “good” bacterium in the human gut and is commonly available in probiotic foods and supplements. The new mouse data show that when this bacterium is present in the maternal gut during pregnancy it can influence the fetal brain’s metabolic environment and the molecular pathways that support growth and neural development.
Conditions such as maternal obesity and chronic stress can alter the maternal gut microbiome and are associated with higher rates of fetal growth abnormalities. Globally, up to about 10% of first-time mothers have infants with low birth weight or fetal growth restriction. Poor growth in the womb increases the risk of neonatal complications and is linked to long-term neurodevelopmental conditions such as cerebral palsy, anxiety, depression and other neuropsychiatric disorders.
The Cambridge team reports that maternal B. breve modified fetal brain metabolites and increased the abundance of transporters for glucose and branched-chain amino acids. They also observed elevated activity in signaling pathways including PI3K-AKT, AMPK, STAT5 and Wnt–β-catenin, along with changes in genes and proteins related to axon formation and mitochondrial function. Together, these changes are consistent with improved nutrient supply and cellular processes that support brain growth.
Previous work from the same group found that maternal treatment with B. breve improves placental structure and function, further promoting nutrient transfer to the fetus. The current findings add that the maternal gut microbiome can also shape fetal brain metabolism directly, suggesting a broader role for maternal microbes in gestational health.
Lead author Dr Jorge Lopez-Tello (Centre for Trophoblast Research, University of Cambridge) said the results indicate that supplying beneficial bacteria to pregnant mothers may support fetal development. Senior author Professor Amanda Sferruzzi-Perri noted that these results encourage a shift in focus toward maternal gut health as part of strategies to address fetal growth restriction, rather than relying solely on interventions that target maternal blood flow or pharmaceutical approaches.
The authors emphasize that this research was performed in mice under tightly controlled conditions, which allowed them to isolate the effects of a single bacterial species. While the findings are promising, confirmation in human studies is essential, as the human gut microbiome is more complex and individual responses may vary. The team plans additional experiments monitoring offspring brain development after birth and examining how B. breve interacts with naturally occurring gut microbiota.
About this probiotics and neurodevelopment research news
Author: Sarah Collins
Source: University of Cambridge
Contact: Sarah Collins – University of Cambridge
Image: The image is credited to Neuroscience News
Original research (open access): “Maternal gut Bifidobacterium breve modifies fetal brain metabolism in germ-free mice” by Jorge Lopez-Tello et al., published in Molecular Metabolism (DOI: 10.1016/j.molmet.2024.102004).
Abstract
Maternal gut Bifidobacterium breve modifies fetal brain metabolism in germ-free mice
Background
Advances in microbiome science have revealed strong connections between gut microbes and host metabolism, yet the specific roles of individual species during pregnancy and fetal development remain underexplored.
Objective
This study examines how maternal colonization with Bifidobacterium breve UCC2003 affects fetal brain metabolism and related pathways when introduced during pregnancy.
Methods
Germ-free pregnant mice were colonized with or without B. breve UCC2003 during gestation. The researchers profiled fetal brain metabolites and assessed the expression of transporters and signaling pathways linked to metabolism, growth and neural development.
Results
Maternal B. breve colonization altered fetal brain metabolism, including reductions in ten specific metabolites (such as citrate, 3‑hydroxyisobutyrate and carnitine) and increased abundance of transporters for glucose and branched-chain amino acids. The probiotic exposure was also associated with higher activity of PI3K‑AKT, AMPK, STAT5 and Wnt–β‑catenin signaling, stabilization of HIF‑2 protein, and changes in genes and proteins involved in cell growth, axon formation and mitochondrial function.
Conclusions
Maternal B. breve during pregnancy can modulate fetal brain metabolism and growth-related pathways in mice. These findings highlight the potential for microbiota-targeted strategies to support gestational health and fetal brain development, pending further investigation in human studies.