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

Abstract

ObjectiveTriggering receptor expressed on myeloid cells (TREM)-1 has recently been recognized as one of the potent amplifiers of acute and chronic inflammation. However, exact role of TREM-1 in regard to insulin insensitivity is unknown.MethodsWe examined the mRNA transcripts and protein expression of TREM-1, TREM-2 and TREM-1/TREM-2 ratio 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 compared with the subjects without obesity (BMI < 30) and diabetes (SO−D−; n=5).ResultsThe 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 to other groups. Overall, increased liver TREM-1 expression and soluble-TREM-1 were found in SO+D+ group compared to SO+D− group (100% vs 57.14%, r=0.582; P=0.023). TREM-1 was significantly increased in all subjects with obesity, those had HOMA-IR index of >2.ConclusionsTREM-1 was found to be significantly higher in tissues biopsies and blood of subjects with obesity. Greater expression and activity of TREM-1 suggests a possible role in the underlying pathophysiology of obesity and associated co-morbidities.