PM20D1 is a circulating biomarker closely associated with obesity, insulin resistance and metabolic syndrome

Eur J Endocrinol. 2021 Dec 10;186(2):151-161. doi: 10.1530/EJE-21-0847.


Objective: Peptidase M20 domain containing 1 (PM20D1), a secreted enzyme catalysing condensation of fatty acids and amino acids into the bioactive lipids N-acyl amino acids (NAAA), induces uncoupling protein 1 (UCP1)-independent adaptive thermogenesis in brown/beige adipocytes in mice. This study aimed to explore the associations of the circulating levels of PM20D1 and major NAAA with obesity-related metabolic complications in humans.

Design and methods: Serum concentrations of PM20D1 and NAAA (C18:1-Leu and C18:1-Phe) in 256 Chinese subjects, including 78 lean and 178 overweight/obese individuals with or without diabetes, were measured with immunoassays and liquid chromatography-mass spectrometry, respectively. The impact of sulfonylurea and rosiglitazone on their circulating levels was examined in 62 patients with type 2 diabetes.

Results: Serum PM20D1 level was significantly elevated in overweight/obese individuals and was closely associated with circulating levels of C18:1-Leu and C18:1-Phe. Furthermore, serum PM20D1, C18:1-Leu and C18:1-Phe concentrations correlated positively with several parameters of adiposity as well as fasting and 2 h postprandial glucose, HbA1c, fasting insulin and HOMA-IR independent of BMI and age. Moreover, a significant elevation in PM20D1, C18:1-Leu and C18:1-Phe concentrations corresponding with increases in the number of components of the metabolic syndrome (MetS) was observed. Treatment with sulfonylurea significantly decreased circulating PM20D1, C18:1-Leu and C18:1-Phe in patients with type 2 diabetes.

Conclusions: Increased serum levels of PM20D1 and its catalytic products NAAA are closely associated with obesity-related glucose dysregulation, insulin resistance and MetS and can be potentially used as clinical biomarkers for diagnosing and monitoring these disorders.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Aged
  • Amidohydrolases / blood*
  • Biomarkers / blood
  • Cross-Sectional Studies
  • Female
  • HEK293 Cells
  • Humans
  • Insulin Resistance / physiology*
  • Male
  • Metabolic Syndrome / blood*
  • Metabolic Syndrome / diagnosis
  • Middle Aged
  • Obesity / blood*
  • Obesity / diagnosis


  • Biomarkers
  • Amidohydrolases
  • PM20D1 protein, human