Increased soluble endoglin levels in newly-diagnosed type 2 diabetic patients are associated with endothelial dysfunction

Endothelial dysfunction (ED) contributes to the pathologic process underlying macrovascular complications, a common complication of type 2 diabetes mellitus (T2DM). Soluble endoglin (sEng) shed from the extracellular domain of the entire endoglin molecule blocks endothelial protection mediated by transforming growth factor-beta 1 (TGF-beta 1). The reactive hyperemia index (RHI), which is determined by reactive hyperemia peripheral arterial tonometry (RH-PAT), is a new index with which to evaluate ED. This study determined the changes in serum sEng levels in newly-diagnosed (untreated) T2DM patients and the correlation with the RHI. The T2DM group included 34 newly-diagnosed T2DM patients, while the control group included 53 healthy adults. The clinical data from the two groups were evaluated retrospectively. The intima-media thickness (IMT) of the common carotid artery (CCA) and the ankle-brachial index (ABI) of both legs were used to assess structural vascular changes. The serum sEng level was determined using an ELISA kit. Endothelial function was assessed using RH-PAT and the RHI was computed. The serum sEng level in the T2DM group was significantly greater than the control group, although the RHI was significantly lower in the T2DM group (p < 0.05). The serum sEng level was negatively correlated with the RHI in T2DM patents (r = 0.354, p = 0.041). The serum sEng level, CCA-IMT, and ABI were not significantly correlated with T2DM (p > 0.05). In summary, among newly-diagnosed T2DM patients, the serum sEng levels were inversely correlated with the RHI, and an elevated sEng level may be associated with ED.