Metabolites distinguishing visceral fat obesity and atherogenic traits in individuals with overweight

Objective: To screen the metabolomes of both overweight subjects with low visceral fat area (LFO) and high visceral fat area (HFO) to identify potential metabolites that are associated with the different metabolic characteristics. Methods: The metabolic characteristics of 112 overweight (25 kg/m² ≤ BMI < 30 kg/m²) Korean individuals aged 30 to 65 years were examined. Plasma metabolomic profiling of HFO [visceral fat area (VFA) at L4 ≥ 100 cm²] and LFO (L4 VFA <100 cm²) individuals matched for age, gender, and BMI was performed. Results: HFO subjects showed higher VFA at L1 and L4 than LFO subjects. The HFO group showed higher blood pressure, lipid profile, high-sensitivity C-reactive protein, malondialdehyde, oxidized low-density lipoprotein (LDL), and homeostasis model assessment-insulin resistance and lower high-density lipoprotein-cholesterol levels. In plasma metabolite identification, the HFO group showed significantly higher levels of long-chain (C14:1, C16:1, C16) acylcarnitines (ACs), medium-chain (C12:1, C12) ACs, urobilinogen, docosahexaenoic acid (C22:6ω3), lysoPE (22:6), lysoPC (22:6), lysoPC (22:5), methoxybenzenepropanoic acid, and isodesmosine. All five ACs correlated positively with VFA and oxidized LDL levels and negatively with high-density lipoprotein-cholesterol levels and LDL particle size. Conclusions: Twelve major metabolites, including three long-chain fatty acids and two medium-chain ACs, are important for distinguishing HFO and LFO. Chronic lipid surplus from visceral fat in HFO is likely associated with substantial increases in plasma medium-chain ACs and long-chain fatty acids, which are closely related to atherogenic traits.