In short, we still lack mechanistic understanding of the roles of vagal sensory neurons in the microbiota-gut-brain axis, calling for more cell-type specific ablation studies in the future

In particular, serotonin can activate vagal afferents via serotonin receptor HTR3A [7], and therefore, may serve as a major signaling molecule between gut microbiota and the vagus nerve

Accumulating evidence is suggesting that the vagus nerve is one of the major routes in the microbiome-gut-brain axis

it has been shown that numerous brain regions are impacted by vagus nerve stimulation, and this connectivity has been termed the “vagus afferent network”.

about two-thirds of enteroendocrine cells are able to make synapses with adjacent nerves

The gastrointestinal (GI) tract is home to ~500 million enteric neurons, ~70% of the body’s immune cells, and over 100 trillion microbes