Increased expression of triggering receptor expressed on myeloid cells-1 in the population with obesity and insulin resistance

Obesity (Silver Spring). 2017 Mar;25(3):527-538. doi: 10.1002/oby.21714. Epub 2017 Jan 23.

Abstract

Objective: Triggering receptor expressed on myeloid cells (TREM)-1 has recently been recognized as one of the potent amplifiers of acute and chronic inflammation. However, the exact role of TREM-1 in regard to insulin insensitivity is unknown.

Methods: mRNA transcripts and protein expression of TREM-1, TREM-2, and TREM-1/TREM-2 ratio were examined in the tissue biopsies (liver, omentum, and subcutaneous fat) and blood samples (neutrophils and monocytes) of subjects with obesity and diabetes (SO+ D+ ; n = 15), subjects with obesity but not diabetes (SO+ D- ; n = 7), and subjects without obesity (BMI < 30) and diabetes (SO- D- ; n = 5).

Results: The immunofluorescence and RT-PCR revealed significant increase in TREM-1, decrease in TREM-2, and increase in the TREM1/TREM2 ratio in SO+ D+ group compared with other groups. Overall, increased liver TREM-1 expression and soluble-TREM-1 were found in SO+ D+ group compared with SO+ D- group (100% vs. 57.14%, r = 0.582; P = 0.023). TREM-1 was significantly increased in all subjects with obesity and those with HOMA-IR index of >2.

Conclusions: TREM-1 was found to be significantly higher in tissues biopsies and blood of subjects with obesity. Greater expression and activity of TREM-1 suggest a possible role in the underlying pathophysiology of obesity and associated comorbidities.

MeSH terms

  • Adult
  • Female
  • Humans
  • Insulin Resistance / physiology*
  • Liver / metabolism
  • Male
  • Membrane Glycoproteins / metabolism*
  • Middle Aged
  • Monocytes / metabolism
  • Myeloid Cells / metabolism*
  • Neutrophils
  • Obesity / metabolism*
  • Omentum / metabolism
  • RNA, Messenger / metabolism
  • Receptors, Immunologic / metabolism*
  • Subcutaneous Fat / metabolism
  • Triggering Receptor Expressed on Myeloid Cells-1

Substances

  • Membrane Glycoproteins
  • RNA, Messenger
  • Receptors, Immunologic
  • TREM1 protein, human
  • TREM2 protein, human
  • Triggering Receptor Expressed on Myeloid Cells-1