Effects of Soluble Epoxide Hydrolase Deficiency on Acute Pancreatitis in Mice

BACKGROUND: Acute pancreatitis (AP) is a frequent gastrointestinal disorder that causes significant morbidity, and its incidence has been progressively increasing. AP starts as a local inflammation in the pancreas that often leads to systemic inflammatory response and complications. Soluble epoxide hydrolase (sEH) is a cytosolic enzyme whose inhibition in murine models has beneficial effects in inflammatory diseases, but its significance in AP remains unexplored. METHODOLOGY/PRINCIPAL FINDINGS: To investigate whether sEH may have a causal role in AP we utilized Ephx2 knockout (KO) mice to determine the effects of sEH deficiency on cerulein- and arginine-induced AP. sEH expression increased at the protein and messenger RNA levels, as well as enzymatic activity in the early phase of cerulein- and arginine-induced AP in mice. In addition, amylase and lipase levels were lower in cerulein-treated Ephx2 KO mice compared with controls. Moreover, pancreatic mRNA and serum concentrations of the inflammatory cytokines IL-1B and IL-6 were lower in cerulein-treated Ephx2 KO mice compared with controls. Further, Ephx2 KO mice exhibited decreased cerulein- and arginine-induced NF-κB inflammatory response, MAPKs activation and decreased cell death. Conclusions -These findings demonstrate a novel role for sEH in the progression of cerulein- and arginine-induced AP.