The study of markers of endothelial dysfunction in metabolic syndrome

BACKGROUND: Metabolic syndrome (MetS) consists of a constellation of metabolic abnormalities that confer increased risk of cardiovascular disease (CVD) and diabetes mellitus (DM). Endothelial dysfunction is one of the key components of MetS which is caused by imbalance between vasodilatory substances like nitric oxide (NO) and vaso-constrictive substances like endothelin and prothrombotic factors like plasminogen activator inhibitor-1 (PAI-1). OBJECTIVE: To study the markers of endothelial dysfunction (NO and endothelin) and prothrombotic markers (PAI-1) among the study subjects. MATERIALS AND METHODS: We enrolled 50 diagnosed cases of MetS as per International Diabetes Federation (IDF) criteria and 50 healthy volunteers as controls. Clinical evaluation included anthropometric, routine biochemical, hematological, serum insulin, NO, endothelin and PAI-1 measurements. RESULTS: Subjects with MetS had higher insulin, endothelin and PAI-1 levels and low NO levels as compared to controls and the difference was found to be significant. The serum insulin levels were positively correlated with PAI-1 and endothelin, and negatively correlated with NO. CONCLUSION: Endothelial functional status as reflected by decreased NO and increased serum endothelin levels along with insulin resistance is seen in MetS. Moreover, higher serum level of PAI-1 also tilts towards a more prothrombotic milieu in the vascular endothelium. Hence endothelial dysfunction and prothrombotic markers may be used to guide for early diagnosis of cardiovascular disease and type 2 diabetes in patients with MetS.