OCT 01, 2019 04:10 PM PDT

Neuroscientists discover gut-brain superhighway

The gut and brain communicate – typically through hormones. Throughout the day, your gut releases hormones that travel through the bloodstream and, over the course of about 10 minutes, reach the brain. These signals tell you that you are hungry, or that you should stop eating. In a recent study, researchers found that there may be a direct gut-brain link via a neural circuit.

The study reveals “a new set of pathways that use gut cells to rapidly communicate with…the brain stem,” says Dr. Daniel Drucker, a clinician-scientist who studies gut disorders at the Lunenfeld-Tanenbaum Research Institute in Toronto, Canada, who was not involved with the work. Although many questions remain before the clinical implications become clear, he says, “This is a cool new piece of the puzzle.”

In 2010, neuroscientist Dr. Diego Bohórquez of Duke University in Durham, North Carolina, discovered that hormone-producing gut cells, called enteroendocrine cells, have protrusions that resemble synapses, or connections between neurons. Based on this anatomical observation, he wondered whether or not these gut cells send signals to the brain through the vagus nerve, which travels from the gut to the brain stem.

To address this, Bohórquez and his team injected a specialized green fluorescent rabies virus – engineered to label cells that share synaptic connections – into the intestines of mice. They noticed that both the enteroendocrine cells and vagal nerves lit up green, researchers report in the journal Science. This means that the cells lining the gut directly communicate with the vagus nerve and the brain.

Next, researchers grew enteroendocrine cells and vagal neurons in a petri dish and observed that gut cells formed synapses with neurons. Then, they showed that common nutrients (sugar) are sensed by enteroendocrine cells, which transmit this sensation to vagal neurons. But how quick does this signal travel? By stimulating enteroendocrine cells, researchers found that these cells released glutamate, a chemical that excites neurons. Cells that communicate using glutamate do so quickly – on a millisecond time scale.

That’s much faster than hormones can travel from the gut to the brain through the bloodstream, Bohórquez says. Hormones’ sluggishness may be responsible for the failures of many appetite suppressants that target them, he says.

“We think these findings are going to be the biological basis of a new sense,” Bohórquez says in a statement. “One that serves as the entry point for how the brain knows when the stomach is full of food and calories. It brings legitimacy to the idea of the ‘gut feeling’ as a sixth sense.”

Source: Science Magazine, TheScientist, Duke Today

About the Author
You May Also Like
OCT 17, 2019
Drug Discovery & Development
OCT 17, 2019
Compound Found in Wine May Treat Anxiety
A study published in the journal Neuropharmacology claims that a compound found in red wine could be used as therapeutic for treating anxiety and depressio...
OCT 17, 2019
Drug Discovery & Development
OCT 17, 2019
Can LSD Treat Addiction?
Modern medicine commonly refers to addiction as a brain disease caused by drugs and other negative stimuli. However, evidence is surmounting that addiction...
OCT 17, 2019
Drug Discovery & Development
OCT 17, 2019
How Does Ecstasy Treat PTSD?
Conventionally, Post Traumatic Stress Disorder (PTSD) is treated via talk therapy, with the aim of getting patients to open up about their trauma and rewir...
OCT 17, 2019
Genetics & Genomics
OCT 17, 2019
Gaining New Insight Into ALS and Other Neurodegenerative Disorders
Scientists have now used a technique called deep mutagenesis to reveal more about amyotrophic lateral sclerosis....
OCT 17, 2019
Neuroscience
OCT 17, 2019
Paralyzed Man Walks Using Brain-Controlled Exoskeleton
Using a brain-controlled robotic suit, a tetraplegic man is able to move his arms and walk. These early results are promising - even astonishing - but authors note that the system is far from...
OCT 17, 2019
Immunology
OCT 17, 2019
Treating Alzheimer's? Target Microglia
The body’s own immune cells may be the common denominator in Alzheimer’s disease. In a new study of the relationship between microglia, tau pro...
Loading Comments...