Untargeted Metabolomic Approach Shows No Differences in Subcutaneous Adipose Tissue of Diabetic and Non-Diabetic Subjects Undergoing Bariatric Surgery: An Exploratory Study.

BACKGROUND: Obesity plays a major role in the development of insulin resistance (IR) and diabetes (T2DM). Increased adipose tissue (AT) is particularly of interest because it activates a chronic inflammatory response in adipocytes and other tissues. AT plays key endocrine and metabolic functions, acting in the regulation of insulin sensitivity and energy homeostasis. Additionally, it can be easily collected during bariatric surgery. The purpose of this pilot study was to explore the potential differences in AT metabolism, through comparing the untargeted metabolomic profiles of diabetic and non-diabetic obese patients undergoing bariatric surgery.

METHODS: For this exploratory study, samples were collected from 17 subjects. Subcutaneous AT (SAT) samples from obese-diabetic (n = 8) and Obese-non-Diabetic (n = 9) subjects were obtained from the Human Metabolic Tissue Bank. Untargeted metabolomic profiling was performed by Metabolon® Inc. Statistical analysis was performed using the MetaboAnalyst 4.0 platform.

RESULTS: Among the 421 metabolites identified and analyzed there were no significant differences between the Obese-Diabetics and the Obese-non-Diabetics. Small changes were observed by fold change analysis mainly in lipid (n = 12; e.g. NEFAs) and amino acid (n = 8; e.g. BCAAs) metabolic pathways. Dysregulation of these metabolites has been associated with IR and other T2DM-related pathophysiological processes.

CONCLUSION: Obesity may influence SAT metabolism masking T2DM-dependent dysregulation. Better understanding the metabolic differences within SAT in diabetic populations may help identify potential biomarkers for diagnosis and monitoring of T2DM in patients undergoing bariatric surgery.