Plasma Fatty Acid Profiles Modulate PPARγ Expression in Adipose Tissue: A Lipidomic Insight Into Obesity-Related Metabolic Dysregulation

Abstract

Aim

This study aimed to investigate the relationship between plasma fatty acids (FAs), FA-derived factors and PPARγ expression in visceral and subcutaneous adipose tissues (VAT and SAT) of obese and nonobese adults.

Methods

This cross-sectional study involved 167 adults aged 19 to 65. Samples of VAT and SAT were obtained during elective abdominal surgeries. Participants were divided into two groups: nonobese (BMI < 30 kg/m²) and obese (BMI ≥ 30 kg/m²). Anthropometric and biochemical measurements were taken, and plasma fatty acids (FAs) were analysed using gas chromatography flame ionisation detection (GC/FID). PPARγ mRNA levels were measured through real-time RT-qPCR.

Results

Obese individuals had higher PPARγ gene expression in both VAT and SAT compared to nonobese participants (p < 0.001). Eighteen FFAs and three new FA-derived factors were identified in both groups, accounting for 69% of the variance in nonobese individuals and 71% in obese individuals. After adjusting for confounding factors, saturated FA (SFA) was associated with PPARγ expression in the SAT of the nonobese group (β = −0.12, p = 0.019). Additionally, total FAs (β = −0.02, p = 0.017), SFA (β = −0.06, p = 0.048), monounsaturated FA (MUFA) (β = −0.08, p = 0.020), polyunsaturated FA (PUFA) (β = −0.03, p = 0.039) and omega-6 FA (β = −0.03, p = 0.040) were associated with VAT PPARγ expression among obese individuals. Conversely, an inverse correlation was observed between factor I of FAs and SAT PPARγ expression in nonobese individuals (β = −0.15; p = 0.027).

Conclusion

These findings suggest that alterations in plasma FA profiles are associated with PPARγ gene expression, particularly in obese individuals. This fact highlights the potential role of dietary FAs in metabolic regulation and health issues related to obesity.