From Microbes to Neurons: Cellular Neuroscience of the Gut–Brain Axis

The gut–brain axis is a dynamic, bidirectional network integrating microbial ecology with neural, immune, and endocrine signaling to shape brain function and behavior. While systemic frameworks are increasingly appreciated, the cellular and subcellular mechanisms translating microbial signals into neural outcomes remain incompletely defined. This Research Topic invites mechanistic, multimodal, and translational studies that uncover how microbial communities and their metabolites interface with neuronal, glial, immune, and epithelial systems across development, health, and disease.

Associations between microbiota states and behavior abound, yet the mechanistic routes—from bioelectrical modulation in the gut epithelium and enteric circuits to glial and neuronal responses in the brain—remain fragmented. Key gaps include: how microbial cues are encoded as bioelectrical and synaptic signals across the gut–vagus–brain axis; how enteric, immune, and endocrine cells coordinate with CNS neurons and glia at single-cell resolution; which microbial metabolites and extracellular vesicles reach neural targets and through what receptors and transporters; and when during development, aging, or disease these processes are most consequential.
This Research Topic addresses these gaps by prioritizing cellular and subcellular mechanisms that translate microbial inputs into neural outputs, integrating electrophysiology, imaging, single-cell/spatial -omics, and behavior, and by emphasizing rigor, reproducibility, and translational relevance to brain health and disease.

We welcome research on the following subtopics:

• Bioelectrical signaling and communication across the gut–brain axis.
• Enteric–central nervous system interactions and cellular crosstalk.
• Microbiota-derived neuroactive molecules and host signaling.
• Microbiota–neuroimmune–neuroendocrine interactions in brain function and behavior.
• Diet, probiotics, and psychobiotics: translational pathways from gut microbes to mental health
• Innovative in vitro and in vivo models of gut–brain connectivity.
• Neurodevelopmental and neurodegenerative outcomes of gut–brain communication.
• Microbiota and neural plasticity and regeneration.