Extracellular vesicle signature is associated with cardio-metabolic improvement after bariatric surgery.

Aims: Bariatric surgery (BS) reduces obesity-associated systemic inflammation leading to multiple cardiovascular (CV) and metabolic benefits. Here, we tested whether measuring vaso-inflammatory cytokines, gut hormones, and circulating extracellular vesicles (EV) provide vaso-inflammatory-metabolic signatures that better correlate to CV-metabolic outcomes after BS, compared to a standard clinical assessment including body weight (BW) loss and traditional CV risk factors.

Methods: In 111 patients with severe obesity, conventional clinical-biochemical parameters and non-conventional vaso-inflammatory-metabolic markers were analyzed at baseline, after 1- (T12) and 3-years (T36) post-BS and were associated to post-surgical BW loss and improvement of patients' CV-metabolic profile.

Results: BW decreased from a median of 111 to 77 Kg at T36 (30 Kg and 32.8% BMI cumulative reduction), and all traditional CV risk factors improved after BS. However, the baseline evaluation of these parameters was unable to discriminate patients according to their CV-metabolic outcome, after BS. This objective was achieved combining the decrease in circulating serum amyloid associated protein, IL-6, TNF-α, and insulin after BS, together with the increase of GLP-1, ghrelin, PYY and bile acids, and changes in EV profiling. Of note, a specific signature given by the reduced expression of several surface antigens carried by EVs and specific single EV markers (i.e., derived from endothelium, platelets, inflammatory cells), successfully discriminated patients at baseline according to their CV-metabolic post-surgical outcome.

Conclusions: Non-conventionally measured vaso-inflammatory-metabolic signatures, and in particular EV profiling, are associated with CV-metabolic outcome after BS and may be integrated to conventional parameters to improve the management and risk stratification of these patients.