The effects of nuclear factor-kappa B in pancreatic stellate cells on inflammation and fibrosis of chronic pancreatitis

Abstract

The activation of pancreatic stellate cells (PSCs) plays a critical role in the progression of pancreatic fibrosis. Nuclear factor-kappa B (NF-κB) is associated with chronic pancreatitis (CP). Previous evidence indicated that NF-κB in acinar cells played a double-edged role upon pancreatic injury, whereas NF-κB in inflammatory cells promoted the progression of CP. However, the effects of NF-κB in PSCs have not been studied. In the present study, using two CP models and RNAi strategy of p65 in cultured PSCs, we found that the macrophage infiltration and MCP-1 expression were increased, and the NF-κBp65 protein level was elevated. NF-κBp65 was co-expressed with PSCs. In vitro, TGF-β1 induced overexpression of the TGF-β receptor 1, phosphorylated TGF-β1–activated kinase 1 (p-TAK1) and NF-κB in the PSCs. Moreover, the concentration of MCP-1 in the supernatant of activated PSCs was elevated. The migration of BMDMs was promoted by the supernatant of activated PSCs. Further knockdown of NF-κBp65 in PSCs resulted in a decline of BMDM migration, accompanied by a lower production of MCP-1. These findings indicate that TGF-β1 can induce the activation of NF-κB pathway in PSCs by regulating p-TAK1, and the NF-κB pathway in PSCs may be a target of chronic inflammation and fibrosis.