Gut Microbiome Composition and Serum Metabolome Profile Among Individuals With Spinal Cord Injury and Normal Glucose Tolerance or Prediabetes/Type 2 Diabetes

Objective: To compare the gut microbiome composition and serum metabolome profile among individuals with spinal cord injury (SCI) and nor-mal glucose tolerance (NGT) or prediabetes/type 2 diabetes (preDM/T2D).Design: Cross-sectional design.Setting: Research university.Participants: A total of 25 adults (N=25) with SCI were included in the analysis and categorized as NGT (n=16) or preDM/T2D (n=9) based on their glucose concentration at minute 120 during a 75-g oral glucose tolerance test. The American Diabetes Association diagnosis guideline was used for grouping participants.Interventions: Not applicable.Main Outcome Measures: A stool sample was collected and used to assess the gut microbiome composition (alpha and beta diversity, microbial abundance) via the 16s ribosomal RNA sequencing technique. A fasting serum sample was used for liquid chromatography-mass spectrometry -based untargeted metabolomics analysis, the results from which reflect the relative quantity of metabolites detected and identified. Gut micro-biome and metabolomics data were analyzed by the Quantitative Insights into Microbial Ecology 2 and Metaboanalyst platforms, respectively.Results: Gut microbiome alpha diversity (Pielou's evenness index, Shannon's index) and beta diversity (weighted UniFrac distances) differed between groups. Compared with participants with NGT, participants with preDM/T2D had less evenness in microbial communities. In particular, those with preDM/T2D had a lower abundance of the Clostridiales order and higher abundance of the Akkermansia genus, as well as higher serum levels of gut-derived metabolites, including indoxyl sulfate and phenylacetylglutamine (P < .05 for all).Conclusions: Our results provide evidence for altered gut microbiome composition and dysregulation of gut-derived metabolites in participants with SCI and preDM/T2D. Both indoxyl sulfate and phenylacetylglutamine have been implicated in the development of cardiovascular diseases in the able-bodied population. These findings may inform future investigations in the field of SCI and cardiometabolic health. Archives of Physical Medicine and Rehabilitation 2022;103:702-10 (c) 2021 The American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.