Analysis of plasma extracellular vesicles in normal-weight and overweight type 2 diabetes mellitus using multimodal SERS and RNA-Seq.

AIMS: To characterize subtype-associated heterogeneity in type 2 diabetes mellitus (T2DM), particularly normal-weight diabetes, using extracellular vesicle (EV)-associated molecular features in a clinically stratified cohort.

METHODS

EV-enriched isolates were obtained from plasma using ExoTIC and validated by transmission electron microscopy, nanoparticle tracking analysis, flow cytometry, and Western blotting. EV-enriched isolates from Asian normal-weight (A-NWD), Asian overweight (A-OWD), Non-Hispanic White normal-weight (W-NWD), and Non-Hispanic White overweight (W-OWD) T2DM patients were analyzed by multimodal surface-enhanced Raman spectroscopy (SERS; n = 65) and EV-RNA sequencing (n = 39).

RESULTS

SERS identified subgroup-associated spectral variation across BMI- and race/ethnicity-stratified groups in this cohort. EV-RNA sequencing identified exploratory differential microRNA (miRNA) expression patterns, with higher miR-208a and miR-132 in A-OWD and higher miR-484 in A-NWD, representing prioritized candidates for future validation. Unsupervised analyses also showed partially overlapping EV-associated molecular features between A-NWD and W-OWD, suggesting that uniform BMI thresholds may not fully capture EV-associated molecular heterogeneity across populations.

CONCLUSIONS

Multimodal EV profiling identified subgroup-associated spectral and exploratory miRNA features in clinically stratified T2DM and provides a framework for studying diabetes heterogeneity, including molecular patterns associated with normal-weight diabetes.