Pinellia ternata lectin exerts a pro-inflammatory effect on macrophages by inducing the release of pro-inflammatory cytokines, the activation of the nuclear factor-κB signaling pathway and the overproduction of reactive oxygen species

Pinellia ternata (PT) is a widely used traditional Chinese medicine. The raw material has a throat-irritating toxicity that is associated with the PT lectin (PTL). PTL is a monocot lectin isolated from the tubers of PT, which exhibits mouse peritoneal acute inflammatory effects in vivo. The present study aimed to investigate the pro-inflammatory effect of PTL on macrophages. PTL (50 mu g/ml)-stimulated macrophages enhanced the chemotactic activity of neutrophils. PTL (50, 100, 200 and 400 mu g/ml) significantly elevated the production of cytokines [tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1 beta and IL-6]. PTL (25, 50 and 100 mu g/ml) induced intracellular reactive oxygen species (ROS) overproduction. PTL also caused transfer of p65 from the macrophage cytoplasm to the nucleus and activated the nuclear factor-kappa B (NF-kappa B) signaling pathway. Scanning electron microscope images revealed severe cell swelling and membrane integrity defection of macrophages following PTL (100 mu g/ml) stimulation, which was also associated with inflammation. PTL had pro-inflammatory activity, involving induced neutrophil migration, cytokine release, ROS overproduction and the activation of the NF-kappa B signaling pathway, which was associated with the activation of macrophages.