VWF and type 2 diabetes mellitus: In another study, metformin was shown to significantly reduce the levels of sVCAM-1, von Willebrand factor (vWF), tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1) and soluble intercellular adhesion molecule-1 (sICAM-1) in patients with type 2 diabetes mellitus.