Feasibility and reproducibility of free fatty acid profiling in abdominal adipose tissue with 1H-magnetic resonance spectroscopy at 3 T: differences between lean and obese individuals.

Abstract

To evaluate the feasibility and reproducibility of free fatty acid (FFA) measurement for diagnosing adipose tissue dysfunction by (1)H-magnetic resonance spectroscopy ((1)H-MRS) in different abdominal adipose tissue depots in healthy obese and lean subjects. Polyunsaturated fatty acids (PUFA), total unsaturated fatty acids (TUFA), triglycerides (TG), and their ratios were determined in three adipose tissue depots of 12 obese and 13 lean subjects. Subjects underwent two separate examinations to assess reproducibility. In lean subjects, 44% of measurements failed due to inclusion of nonadipose tissue in the spectroscopy voxel, as opposed to 23% in obese subjects. Reproducibility of PUFA, TUFA, and TG was moderate to good in obese subjects (intraclass correlation coefficients [ICCs] 0.18-0.75), and poor to moderate in lean subjects (ICCs -1.04-0.55) in subcutaneous and omental adipose tissue. In the perirenal adipose tissue, ICCs were poor in both lean and obese subjects (-0.794-0.013). PUFA/TUFA and PUFA/TG were higher in omental adipose tissue in obese vs. lean subjects (35*10(-3) vs. 0.16*10(-3), P = 0.01 and 2.05*10(-3) vs. 0.01*10(-3), P = 0.02, respectively). (1)H-MRS is a feasible and reproducible method for FFA profiling in abdominal adipose tissue in abdominally obese individuals. (1)H-MRS has potential as diagnostic tool for noninvasive identification of adipose tissue dysfunction.