Increased expression of triggering receptor expressed on myeloid cells-1 in the population with obesity and insulin resistance.
Level 4 - case-series / case-control
Cross-sectional comparative study with human tissue and blood samples
PubMed 28111922 · doi:10.1002/oby.21714
What was done
mRNA transcripts and protein expression of TREM-1, TREM-2, and the TREM-1/TREM-2 ratio were measured using RT-PCR and immunofluorescence in tissue biopsies (liver, omentum, subcutaneous fat) and blood (neutrophils, monocytes). The study compared three groups: subjects with obesity and diabetes (n = 15), subjects with obesity without diabetes (n = 7), and non-obese non-diabetic controls (BMI < 30 kg/m², n = 5).
What was found
Subjects with obesity and diabetes had significantly increased TREM-1, decreased TREM-2, and an increased TREM-1/TREM-2 ratio compared to other groups. Increased liver TREM-1 and soluble TREM-1 were found in 100% of the obese diabetic group versus 57.14% of the obese non-diabetic group (r = 0.582, P = 0.023). TREM-1 was also significantly higher in all subjects with obesity and in those with HOMA-IR > 2.
Why it matters
This study provides human tissue evidence that TREM-1 upregulation is linked to obesity and insulin resistance, indicating a potential role in obesity-associated chronic inflammation.
Limits
The sample size is very small (total n = 27, with only 5 control subjects). The cross-sectional design cannot establish causality between TREM-1 activation and the development of insulin resistance, and detailed quantitative expression values were not provided in the abstract.
Cited by
- partial Obesity and diabetes significantly increase the ratio of TREM1 to TREM2 receptors in microglia, favoring pro-inflammatory activity.