Research at the MGH is interwoven throughout more than 30 departments, centers and units, and is conducted with the support and guidance of the MGH Research Institute. The Research Roundup is a monthly series highlighting studies, news and events.

This sugar substitute may not be so sweet after all

Did you make the switch to artificial sweeteners, but still have trouble taking off the pounds? Researchers at the MGH may have identified a reason why the artificial sweetener aspartame could actually be an obstacle to weight loss.

In a new study, the team demonstrated that an amino acid produced as a byproduct of aspartame digestion blocks the functioning of a digestive enzyme shown to prevent obesity.

In a series of experiments, the team demonstrated the activity of this enzyme was reduced when it was added to a solution containing aspartame, but not when added to a solution with sugar. In a second experiment, the team showed mice on a high-fat diet who received aspartame in their drinking water gained more weight than mice that were fed a similar diet but drank only water.

More research is now needed to confirm the results in humans and to identify any othermechanisms that might contribute to the weight gain.

Richard Hodin, MD, of the MGH Department of Surgery, is the study’s senior author.

Blood test may not accurately measure intestinal healing in pediatric celiac disease

In a new finding, researchers from the MassGeneral Hospital for Children (MGHfC) and Boston Children’s Hospital found that 20 percent of children with celiac disease still show intestinal damage even after strict adherence to a gluten-free diet.

The study examined 103 children with celiac disease who had been on gluten-free diets for a year and had been determined to comply well with the dietary restrictions. Biopsies revealed that approximately 20 percent of these patients continued to show intestinal damage, even though they reported feeling better and no longer had blood test results indicating celiac disease.

Findings from this study have already been translated into clinical practice at MGHfC, where most pediatric patients age 10 and older will now be tested with both endoscopy and a blood test after a year on a gluten-free diet. The previous guidelines called for endoscopy only at diagnosis,with subsequent monitoring by blood test after a year.

Although the long-term risks for children with persistent intestinal damage are not clear, such damage in adults has been linked to an increased risk of lymphoma (a cancer that affects the immune system), low bone density and more frequent bone fractures.

Maureen Leonard, MD, MSSc, and Alessio Fasano, MD, of the Center for Celiac Research and Treatment, led the study. 

Read more articles from the 12/09/16 Hotline issue.