Inflammation in the subcutaneous adipose tissue does not attenuate endothelial function in subjects with diabetes mellitus and subjects with dyslipidaemia and hypertension: A cross-sectional study.

Background: Obesity is associated with low-grade inflammation that may be related to vascular disease. We hypothesized that inflammation in the subcutaneous adipose tissue is associated with impaired endothelium-dependent vasodilatation.

Methods: We assessed endothelial function by measuring forearm vascular response to acetylcholine and determined inflammation in subcutaneous fat biopsies in 2 groups of subjects; 15 patients with type 2 diabetes mellitus (T2DM) and 19 subjects with dyslipidaemia combined with hypertension (DcH). The adipose tissue inflammation score was based on adipocyte size, influx of macrophages and presence of crown-like structures. We compared the vascular response to acetylcholine between subjects with and without adipose tissue inflammation.

Results: Patients with diabetes had clearly decreased vasodilatation compared to patients with DcH. In total, 23 of the 34 fulfilled the criteria of subcutaneous adipose tissue inflammation. However, there was no difference in vascular response to acetylcholine between the group with and without inflammation (changes in FBF from baseline 3.9 ± 0.8, 7.8 ± 1.0 and 13.6 ± 1.0 mL/dL/min compared to 4.3 ± 1.0, 7.9 ± 2.1 and 12.2 ± 2.4 mL/dL/min in response to acetylcholine 0.5, 2.0 and 8.0 μg/dL/min), nor was there a relationship between systemic hs-CRP levels and endothelial function.

Conclusions: We confirm that subjects with T2DM have impaired endothelial function compared to age- and BMI-matched subjects with DcH. However, endothelial function did not differ between participants with or without inflammation in the subcutaneous adipose tissue. These results suggest that fat tissue inflammation, at least in the subcutaneous compartment, does not affect vascular function.