Nuclear Factor-κB Increases Intracellular Calcium by Upregulation of Na+-Ca2+ Exchanger 1 in Cerulein-Induced Acute Pancreatitis

Objectives: The mechanisms underlying pathogenesis of acute pancreatitis (AP) are still not completely understood. An early, critical feature of AP is aberrant calcium (Ca) signaling, termed Ca overload, within pancreatic acinar cells. This study aimed to develop a model system in rats for AP induction to study the contribution of the Na-Ca exchanger 1 (NCX1) ion channel in AP pathogenesis.

Methods: To establish a rat model of AP induction, cerulein or L-arginine were intraperitoneally injected and tissue was histologically analyzed by hematoxylin and eosin staining. A cell culture-based model for AP induction was similarly created through cerulein treatment of AR42J cells. Induction of AP was also examined following exposure to the NXC1-targeted inhibitor KB-R7943. The expression of each gene was detected by Western blotting, immunofluorescence, immunohistochemistry, or quantitative reverse transcription polymerase chain reaction. Transcriptional regulation by nuclear factor (NF)-κB was detected using an NCX1 promoter-fusion dual luciferase reporter system. Cytosolic Ca was measured using a fluorescent calcium indicator.

Results: We found that cerulein induced NCX1 expression via activation of nuclear factor NF-κB, which potentially binds to the NCX1 promoter to induce its transcription.

Conclusions: Our findings reveal a regulatory pathway through NF-κB/NCX1 governing Ca overload in AP development, thus providing potential targets for AP treatment.