Tanycytes — cells found in part of the brain that controls energy levels — detect two key amino acids in food and tell the brain directly that we feel full, according to new research from the University of Warwick.

“Tanycytes in the brain respond to amino acids found in foods, via the same receptors that sense the flavor of amino acids (umami taste), which are found in the taste buds of the tongue,” said Professor Nicholas Dale from the University of Warwick’s School of Life Sciences and colleagues.

“Two amino acids that react most with tanycytes — and therefore are likely to make you feel fuller — are arginine and lysine.”

“These amino acids are found in high concentration in foods such as pork shoulder, beef sirloin steak, chicken, mackerel, plums, apricots, avocadoes, lentils and almonds — so eating those foods will activate the tanycytes and make you feel less hungry quicker.”

Professor Dale and co-authors made their discovery by adding concentrated amounts of arginine and lysine into brain cells, which were made fluorescent so that any microscopic reactions would be visible.

The researchers observed that within 30 seconds, the tanycytes detected and responded to the amino acids, releasing information to the part of the brain that controls appetite and body weight.

They found that signals from amino acids are directly detected by the umami taste receptors by removing or blocking these receptors and observing that the amino acids no longer reacted with tanycytes.

“Amino acid levels in blood and brain following a meal are a very important signal that imparts the sensation of feeling full,” Professor Dale said.

“Finding that tanycytes, located at the center of the brain region that controls body weight, directly sense amino acids has very significant implications for coming up with new ways to help people to control their body weight within healthy bounds.”

This discovery opens up new possibilities for creating more effective diets — and even future treatments to suppress one’s appetite by directly activating the brain’s tanycytes, bypassing food and the digestive system.

The research is published in the journal Molecular Metabolism.

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Greta Lazutkaite et al. Amino acid sensing in hypothalamic tanycytes via umami taste receptors. Molecular Metabolism, published online September 14, 2017; doi: 10.1016/j.molmet.2017.08.015