sFasL-mediated induction of neutrophil activation in patients with type 2 diabetes mellitus

Fas/Fas ligand system was shown to be related to insulin resistance and type 2 diabetes mellitus (T2DM). However, the role of soluble Fas ligand (sFasL) in functioning of immune cells in type 2 diabetes mellitus (T2DM) has not been studied yet. The aim of the present study was to determine in vitro effects of sFasL on neutrophil activation and apoptosis. We demonstrate here that sFasL exhibited proinflammatory effect and induced mRNA levels of caspase-1, NF-κB, IL-1β and CD18 expression. At the same time, sFasL induced reactive oxygen species (ROS) production. Activation of caspase-1 activity abolished sFasL-dependent apoptosis, and suppressed Fas expression and mRNA levels of caspase-3 in neutrophils from T2DM patients. Collectively, our findings identify a novel proinflammatory role of sFasL in T2DM neutrophils that is dependent of caspase activity. Thus, sFasL enhances inflammatory response of neutrophils from T2DM patients without increasing apoptosis suggesting its triggering role in T2DM inflammation.