Guar gum fiber limits inflammation and delays the onset of MS symptoms in mice

Guar gum fiber limits inflammation and delays the onset of MS symptoms in mice

A diet high in guar gum, a common food additive, and fiber limited inflammation and delayed the onset of multiple sclerosis (MS) symptoms in mice, according to a new study by members of the Department of Microbiology and Immunology at the University of British Columbia (UBC).

“The rapid increase in autoimmune and inflammatory diseases in developed countries in recent decades suggests that dietary choice is an environmental factor contributing to incidence,” said Dr. Lisa Osborne, lead researcher on the study and assistant professor at UBC Microbiology and Immunology.

"Fiber is a powerful modulator of immune responses and can control inflammation in numerous diseases, but it is a very biochemically diverse family. Our study gives us a clearer insight into the potential of different fiber sources for maintaining immune health."

Dr. Osborne and colleagues exposed groups of mice to a variety of diets - a control diet with five percent cellulose fiber, a diet completely lacking fiber, or diets enriched with fiber in resistant starch, inulin, pectin, etc. (30%). Guar gum. Quark was the only type of fiber that significantly reduced MS-like symptoms.

Guar gum – guaran – is derived from guar beans and is often used as an additive to thicken and stabilize food and feed, as well as in industrial applications. India and Pakistan are the largest producing countries of the bean.

Guar beans are not as common in the Western diet and the gum is not used as an additive in these high quantities in the West.

Experts keep saying that fiber is good for you—and a variety of sources of fiber are important for immune health—but not much critical work has been done to understand how the body responds to different types of fiber. It’s fascinating that this particular source has such an impact.”

Naomi Fettig, lead author and PhD student, Department of Microbiology and Immunology at UBC

In the USA and Canada, the average daily fiber intake is 15 grams - current recommendations are twice as high at 30 grams. The recommended values ​​do not take any specific fiber type into account. “At the doses we administered to mice, it may be difficult to integrate guar beans,” says Dr. Osborne. “But a guar gum derivative, partially hydrolyzed guar gum, is commercially available as a prebiotic.”

After the mouse microbiota breaks down gums, the resulting molecules appear to reduce the activity and proliferation of a type of CD4+ T cells, Th1 cells, which play a key role in activating the autoimmune response. It is this reaction that causes MS-like symptoms in mice. The effects of fiber on Th1 cells were largely unknown before this study, and these results suggest that the biochemical differences in fiber structures may influence different immune pathways.

Dr. Osborne and her lab now want to explore the potential benefits in humans – including developing a more detailed understanding of the molecular picture that could help develop therapeutics that provide the benefits of such a guar gum diet in a more practical form.

Source:

University of British Columbia, Faculty of Science

Reference:

Fettig, NM, et al. (2022) Inhibition of Th1 activation and differentiation by dietary guar gum ameliorates experimental autoimmune encephalomyelitis. Cell Reports. doi.org/10.1016/j.celrep.2022.111328.