VANCOUVER, BC—The beneficial effects of oral propionate, an approved food additive, have been demonstrated in humans for the first time, according to a study presented at the 68th Annual AAN Meeting.  

The study sought to examine the effects of oral propionate, a short chain fatty acid, on regulatory T (Treg) cells, which can suppress the potential deleterious activities of T helper cells, an immune response in multiple sclerosis. Prof Dr med. Aiden Haghikia, of the Department of Neurology at Ruhr-University Bochum and St. Josef-Hospital, Bochum, Germany, and colleagues assessed the effects of oral propionate 1g daily in healthy and MS patients, for a period of 14 to 60 days, including washout intervals.

Results showed that the propionate capsules were well tolerated by all volunteers, with no side effects noted. Treg frequencies in all treated individuals increased significantly to between 25% to 30%, accompanied by a decrease of Th17 cells. The increased Treg frequencies were maintained for 2 to 3 weeks after withdrawal of propionate, although frequencies returned to pretreatment levels after 2 months of washout.

The findings are noteworthy in that they contrast previous findings on the effects of long chain fatty acids, which have been shown to be detrimental to the course of experimental autoimmune encephalomyelitis (EAE), a model of MS. Short chain fatty acids, on the other hand, can improve EAE by promoting Treg differentiation.

“Our results underline the influence of short chain fatty acid propionate on the systemic immune response and may be included in an add-on regimen in addition to established first line MS drugs,” the study investigators concluded.