Fasting serum free glycerol concentration is a potential surrogate marker of visceral obesity and insulin sensitivity in middle-aged Japanese men

• Published in: Journal of clinical lipidology Vol. 14; no. 4; pp. 522 - 530
• Main Authors: Hirayama, Satoshi, Hori, Atsushi, Isshiki, Miwa, Hirayama, Akiko, Ueno, Tsuyoshi, Tamura, Yoshifumi, Kaga, Hideyoshi, Watada, Hirotaka, Kawamori, Ryuzo, Miida, Takashi
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.07.2020
• Subjects: Free glycerol; Insulin resistance; Lipoprotein lipase; Metabolic syndrome; Visceral fat; Visceral fat; Insulin resistance; Lipoprotein lipase; Metabolic syndrome; Free glycerol
• ISSN: 1933-2874; 1876-4789
• DOI: 10.1016/j.jacl.2020.06.003

Triglyceride (TG) is a tri-ester composed of a glycerol and 3 fatty acids. Degradation of TG in adipose tissue is increased in the fasting state but inhibited in the postprandial state. Although insulin suppresses adipose TG degradation, patients with insulin resistance have high concentrations of insulin and free glycerol (FG) in the fasting state. We examined whether the fasting FG concentration reflects visceral obesity and insulin sensitivity in middle-aged Japanese men. We measured the fasting serum FG concentration in 72 males aged 30 to 50 years using a simple enzymatic method. The subjects were divided into tertiles according to their homeostasis model assessment of insulin resistance (HOMA-IR). Besides routine glucose- and lipid-related parameters, we determined insulin sensitivity as the rate of glucose disappearance in a 2-step hyperinsulinemic-euglycemic clamp and the abdominal visceral fat area (VFA) by magnetic resonance imaging. The highest HOMA-IR tertile group had a higher fasting FG concentration than the middle- and lowest-tertile groups (0.077 ± 0.024 vs 0.063 ± 0.017 and 0.061 ± 0.016 mmol/L, P < .05 and P < .01). The FG concentration was positively correlated with VFA (rs = 0.36; P < .01) and the HOMA-IR score (rs = 0.26, P < .05) but negatively correlated with insulin sensitivity (rs = −0.26, P < .05). Multivariate regression analysis revealed that the FG concentration is independently associated with VFA and insulin sensitivity. The fasting FG concentration reflects VFA and insulin sensitivity in middle-aged Japanese men. The fasting FG concentration may be a potential surrogate marker of visceral obesity and insulin resistance in outpatients. •We measured the fasting free glycerol (FG) levels in 72 middle-aged Japanese men.•The fasting FG level was positively correlated with visceral fat area.•The fasting FG level was negatively correlated with insulin sensitivity.•The fasting FG concentration reflects visceral obesity and insulin resistance.•The fasting FG level may be a surrogate marker of visceral fat area and insulin resistance.