Microbiota Transplantation in Individuals with Type 2 Diabetes and a High Degree of Insulin Resistance

The objective of this study was to determine the results of fecal microbiota transplantation (FMT) from healthy lean subjects in patients with type 2 diabetes (T2D); Methods: We designed a phase II, randomized, single-blind, parallel-arm clinical trial. Twenty-one subjects (12 men [57.1%] and 9 women [42.9%]), who had previously signed an informed consent were randomized to FMT from lean donors, a probiotic (Lactobacillus delbrueckii spp. bulgaricus LB-14), or placebo. Mean age at baseline was 62.5 ± 5.8 years and mean body mass index (BMI) at baseline was approximately 32.4 ± 2.4 kg/m². Anthropometric measures, biochemical variables, oral glucose tolerance test (OGTT), and a stool microbiota analysis were performed (baseline, 4 and 12 weeks). The trial was conducted following the Declaration of Helsinki, Good Clinical Practice Guides (CPMP/ICH/135/95) and the current Spanish legislation regarding clinical trials (RD 223/2004).; Results: FMT changes occurred at the expense of the species found in the donor. No differences in weight, body mass index, HbA1c, or the results of the OGTT for glucose and insulin were found between groups after the intervention, although a decrease in uric acid was observed in the probiotic group (-0.5 mg/dL; p = 0.037) and a mild increase in HbA1c in the FMT group (+0.25%; p = 0.041); Conclusions: In our sample, neither FMT from healthy and lean donors nor a probiotic were effective in improving insulin sensitivity and HbA1c in patients with T2D.