Gut's taste for the sweet life revealed

A sugar-sensing receptor in the intestine could explain why drinking diet cola may hinder obese people who hope to lose weight^1,2 and lead to new ways of treating obesity and diabetes. 

A joint team of scientists from the University of Liverpool, UK, and from New York’s Mount Sinai School of Medicine, US, discovered that the receptor, also found in the tongue, controls how much sugar the body absorbs from food in the gut. 

Scientists have previously shown that a transporter protein in the gut called SGLT1 moves sugar from the gut into the body. Cells lining the gut produce more SGLT1 in response to sugar-rich food, but until now, how the cells detected sugar was unclear. 

To see if the gut’s sugar receptor was involved, the team knocked out the gene for the receptor in mice and found they lost the ability to regulate the production of SGLT1. The researchers were also surprised to discover that the receptor detected the artificial sweeteners present in ’diet’ foods and drinks. 

’This explains why humans and animals fail to lose weight with low-calorie artificial sweeteners: they stimulate increased glucose absorption from carbohydrate breakdown in the gut,’ said Soraya Shirazi-Beechey, who led the Liverpool team. 

The team is now looking at how the receptor might be tweaked to help the obese or diabetic. ’Diabetes for example, is where the body’s blood sugar level is higher than normal; if we could use the . receptor like a dimmer switch, we could set it so that the appropriate amount of sugar is absorbed in the body,’ Shirazi-Beechey said. 

Lionel Milgrom