Fecal Microbiota Transplantation Improves Blood Glucose Homeostasis in Patients with Brittle Type 1 Diabetes

Background: Patients with brittle type 1 diabetes are more prone to extreme swings in blood glucose levels, resulting in frequent bouts of hyper- or hypo-glycemia. The intestinal microbiota plays an important role in regulating glucose homeostasis. We therefore investigated the effect of fecal microbiota transplantation (FMT) from healthy donors on glycemic stability in recipients with brittle type 1 diabetes.

Methods: A total of 12 patients with brittle type 1 diabetes participated in this clinical trial and received FMT treatment for three consecutive days. Profiles of blood glucose, blood lipids, serum metabolites and fecal metabolites were all examined at baseline and at 1 week, 1 month, 3 months, 6 months post-FMT intervention. We also analyzed compositions of subjects’ gut microbiota at the same timepoints.

Results: Compared with baseline, FMT intervention significantly improved blood glucose homeostasis in those recipients, an effect that could be maintained for up to 3 months. The most striking observation was reduced glycemic fluctuations and a decreased incidence of asymptomatic hypoglycemia. We also observed dramatic changes in serum metabolites after FMT, including decreased levels of branched-chain fatty acids and aromatic amino acids. Furthermore, levels of fecal short chain fatty acids (SCFAs), especially that of butyrate, were significantly increased at 1 week and 1 month post-FMT treatment, in keep with increased butyrate-producing bacteria.

Conclusions: FMT significantly improved glucose homeostasis in patients with brittle type 1 diabetes. The beneficial effects of FMT on glycemic stability are associated with changes in intestinal microbiota and serum/fecal metabolites.