Anti-inflammatory Effect of Full-Length Adiponectin and Proinflammatory Effect of Globular Adiponectin in Esophageal Adenocarcinoma Cells

Abstract

Adiponectin, an adipocyte-derived hormone with anti-inflammatory and antitumor activity, inhibits esophageal adenocarcinoma (EAC) cell proliferation and induces apoptosis. Chronic inflammation is a key process involved in initiation and progression of EAC, but the roles and mechanisms of adiponectin in inflammation have not been fully understood in EAC. We aimed to analyze the effects of two types of adiponectin, full-length adiponectin (f-Ad) and globular adiponectin (g-Ad), on inflammatory factors' expression and explore the roles of ROS/NF-κB signaling pathway in adiponectin-regulated inflammation in EAC cells. It was found that f-Ad and g-Ad differently regulated both mRNA and protein levels of TNF-α, IL-8, and IL-6 in a dose-dependent manner in OE19 cells. g-Ad apparently induced TNF-α, IL-8, and IL-6 production, which was inhibited by PDTC or NAC, and increased intracellular ROS levels and NF-κB p65 activation, whereas f-Ad significantly suppressed production of inflammatory factors and NF-κB p65 activation and also decreased the intracellular ROS levels. In conclusion, the study demonstrated that g-Ad exerts a proinflammatory effect whereas f-Ad appears to induce an anti-inflammatory effect in a ROS/NF-κB-dependent manner in OE19 cells.