New Research Connects Gut Microbiota & Celiac Disease
by Natasha Trenev
Celiac Disease (CD), also referred to as gluten intolerance, can mean a lifetime of avoiding grains containing gluten, wheat, rye and barely. Exposure to even the smallest amount of gluten can trigger a damaging and sometimes painful gastrointestinal reaction in people who are sensitive to the stuff. Avoiding gluten altogether can be very difﬁcult, and the quest to avoid it can disrupt the lives of those suffering from the sensitivity, as well as the lives of family members. Due to the constraints of a gluten-free diet, alternative therapies for CD are being explored.
About Celiac Disease
Celiac Disease affects approximately one in 133 Americans, or around 2.18 million Americans. Symptoms can range from classic gastrointestinal disturbances like diarrhea, reﬂux, abdominal pain and bloating, to more complex symptoms such as malnutrition, weight loss, fatigue, easy bruising, skin rashes, anemia and other isolated nutrient deﬁciencies.
The gastrointestinal tract breaks down food into smaller components the body can absorb and use for various purposes. People with CD cannot break down gluten into proteins small enough for their bodies to digest. With repeated exposure to larger, unaltered proteins, the body may develop an immune response to gluten.
The Connection between Microbes in the Gut and Gluten Sensitivity
Some of the newest research shows an association between gluten sensitivities and the bacteria living in the intestinal tract known as the gut microbiota. Bacteria living in the small intestine participate in the metabolism of gluten. Scientists know that people with gluten sensitivities tend to have a different set of bacteria living in their intestines compared with those without the dietary problem.
Scientists wanted to know, though, if the bacterial communities from a person with gluten sensitivities would handle wheat proteins differently than the bacterial communities of a person without the condition. To ﬁnd out, researchers from McMaster University in Canada isolated gluten-degrading bacteria from the small intestines of participants with and without gluten sensitivities. The scientists then transferred the bacteria from both groups into germ-free lab mice, which had no intestinal bacteria at all, and then created colonies of the mice. Next, the scientists fed gluten to the mice and observed the results.
Microbes in the small intestine trigger immune reactions when they encounter gluten. The scientists determined that the microbes from a person with gluten sensitivities trigger different immune reactions than do the microbes from someone without the sensitivity. Speciﬁcally, the bacteria from those with gluten sensitivities reacted by producing peptides which talk differently to immune cells and provoke a stronger immune response.
The researchers then tested how various peptides isolated from people with gluten sensitivities reacted with blood immune cells. They found that certain peptides from gluten-sensitive individuals activated gluten-speciﬁc immune cells. The scientists also found that different bacteria isolated from healthy people were able to degrade the peptides in a way that decreases gluten-related immune reactions.
The research underscores the link between gut bacteria and the immune system during gluten metabolism. The results of the study highlight the roles bacteria play in modulating the body’s reaction to gluten. The ﬁndings are also consistent with the theory that imbalances in bacteria could contribute to the symptoms of gluten sensitivities, even though the bacteria included in the study may not be the only ones capable of modifying gluten digestion.
New Research Indicates Speciﬁc Probiotic Bacteria May Help
In another study published in the Journal of Clinical Gastroenterology, supplementation with the probiotic bacteria Biﬁdobacterium infantis NLS super strain was shown to alleviate some gastrointestinal symptoms associated with celiac disease in newly-diagnosed participants who were still consuming a gluten containing diet. In that study, researchers randomly assigned participants to either the test group receiving B. infantis probiotic capsules, or the control group receiving a placebo capsule. Participants took two capsules three times each day, 15 minutes before meals, for three weeks. The researchers gathered data on the participants on the ﬁrst day of the study, on day 10, and again 21 days later at the end of the study. Data included vital signs, safety reports, urine and blood tests, and questionnaires.
The researchers found that some gastrointestinal symptoms improved for participants who took B. infantis probiotic, speciﬁcally indigestion, constipation and gastroesophageal reﬂux. Furthermore, the scientists noted administration of the B. infantis probiotic was not associated with serious adverse effects or signiﬁcant biochemical changes. The researchers also noted that these changes took place despite the fact the participants were still consuming gluten. In the future, they hope to repeat this study to see what changes occur in a similar group already on a gluten-free diet.
Infants, B. infantis and Celiac Disease Development
In addition to the role that Biﬁdobacterium infantis has been shown to have in people with active CD, it’s also been well studied for its importance in the infant gut. Breast milk has been shown to stimulate the growth of B. infantis in the guts of healthy newborns. Researchers at the University of California, Davis, have even gone so far as to name it the “Champion Colonizer of the Infant Gut.” In one study of 164 healthy infants who have at least one ﬁrst-degree relative with celiac disease, they found reduced numbers of Biﬁdobacterium in infants who later had an increased risk for developing celiac disease. This indicates that the type of milk fed, the gut bacteria that develop early on, and genetic predisposition may all play a role in the development of Celiac Disease later in life.
Research continues to show a connection between microbes living in the gut and celiac disease. These studies are early indicators of the use of speciﬁc strains of probiotics as supportive supplements for people who suffer from celiac disease and ongoing research may someday help provide non-dietary treatments for people who suffer from celiac disease.