Introduction: Plasma levels of adiponectin (APN), are significantly reduced and IL-6 levels are elevated in diabetic patients, but their relations with endothelial dysfunction remains unclear.

Methods: We have observed 40 consecutive patients with type 2 diabetes mellitus (mean age 61 ± 5), with or without nephropathy. We have measured endothelial dysfunction with the Endo-PAT, that is the only FDA approved non-invasive device that reliably endothelial function. We assessed the arterial stiffness by a non-invasive new tool known as ‘‘e-tracking, Aloka, Japan’’ We have compared the data of endothelial function with the measurement of 50 healthy volunteers. Patients were divided in two groups: group A with normal endothelial index following international references (EFI>1.7) and group B with reduced endothelial function (EFI <1.7). For each patient a blood sample was collected in tubes containing EDTA as anticoagulant. Samples were centrifuged at +4°C for 15’ at 3000g and than stored at −80°C until assayed. Adipocytokines (IL-6 and APN) plasma levels were measured with commercially available ELISA kits following producer’s protocol.

Results: IL-6 and APN were negatively (r: −0.51; p<0.05) and positively (r:0.54; p<0.05) correlated respectively with endothelial index in group B. Arterial stiffness (ß parameter) was negatively correlated (r: −0.30; p<0.05) with APN levels in group B. The presence of microvascular complications such as nephropathy was also associated with older age and longer duration of the disease.

Conclusions: patients affect by type 2 diabetes mellitus, endothelial disfunction and carotid arterial stiffness are correlated with plasma levels of IL-6 and APN, independently of presence of nephropathy.