2023/03/20

Potential for personalized dietary treatment of irritable bowel syndrome

A new study, led by researchers at CIC bioGUNE, suggests specific DNA changes may affect the response to carbohydrate-focused diets.

Researchers at CIC bioGUNE, a member of the Basque Research & Technology Alliance (BRTA), report that DNA variations in the gene coding for sucrase-isomaltase (an enzyme involved in the digestion of carbohydrates), are important for the response to a sucrose- and starch-restricted diet used to treat patients with irritable bowel syndrome (IBS).

IBS is the most common gastrointestinal disorder, affecting more than 10% of people worldwide with symptoms including abdominal pain, gas, diarrhoea and constipation. What causes IBS is largely unknown, which hampers the development of effective treatment for many patients. However, patients often experience symptoms after eating certain foods, and a role for dietary carbohydrates as triggers of IBS with diarrhea (IBS-D) has been demonstrated in some patients, who may be treated with diets restricting the intake of specific carbohydrates.

In their work published as a Letter in the journal Gut, an international team led by Ikerbasque Research Professor Mauro D’Amato at CIC bioGUNE, together with Dr Luis Bujanda at Biodonostia, researchers from the Basque Culinary Center and other collaborators from Sweden and Germany, studied the genetic profile of Spanish and Swedish IBS-D patients who had been treated with a diet restricting the intake of sucrose and starch (SSRD). Based on D’Amato’s previous research, they sought for DNA changes (polymorphisms) in the SI gene that produces the sucrase-isomaltase, an intestinal enzyme that is key to the digestion of carbohydrates, especially sucrose and starch. They found that IBS-D patients with defective forms of the SI enzyme (thus unable to properly digest sucrose and starch) were more likely to benefit from the SSRD diet than other patients. This adds up to previous results from the same team showing that SI polymorphisms affect people’s risk of IBS, as well their likelihood to respond (less) to another carbohydrate-focused diet, restricting the intake of FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides and polyols).

“While the genetic make-up of people’s SI gene appears to be important for their predisposition to IBS, we also see that this may affect the possibility to successfully treat them with specific carbohydrate-restricted diets” commented Prof D’Amato “and this holds potential for a personalized (dietary) management of a subgroup of patients based on their genetic profiles”.

Publication
https://gut.bmj.com/content/early/2023/03/05/gutjnl-2023-329695

CIC bioGUNE, miembro del Basque Research & Technology Alliance, BRTA

Spanish version