Real-time monitoring of inflammation status in 3T3-L1 adipocytes possessing a secretory Gaussia luciferase gene under the control of nuclear factor-kappa B response element

Abstract

We have established 3T3-L1 cells possessing a secretory Gaussia luciferase (GLuc) gene under the control of nuclear factor-kappa B (NF-κB) response element. The 3T3-L1 cells named 3T3-L1-NF-κB-RE-GLuc could differentiate into adipocyte as comparably as parental 3T3-L1 cells. Inflammatory cytokines such as tumor necrosis factor (TNF)-α and interleukin (IL)-1β induced GLuc secretion of 3T3-L1-NF-κB-RE-GLuc adipocytes in a concentration- and time-dependent manner. GLuc secretion of 3T3-L1-NF-κB-RE-GLuc adipocytes was also induced when cultured with RAW264.7 macrophages and was dramatically enhanced by lipopolysaccharide (LPS)-activated macrophages. An NF-κB activation inhibitor BAY-11-7085 and an antioxidant N-acetyl cysteine significantly suppressed GLuc secretion induced by macrophages. Finally, we found that rosemary-derived carnosic acid strongly suppressed GLuc secretion induced by macrophages and on the contrary up-regulated adiponectin secretion. Collectively, by using 3T3-L1-NF-κB-RE-GLuc adipocytes, inflammation status can be monitored in real time and inflammation-attenuating compounds can be screened more conveniently.