Anti-inflammatory effects of calcium citrate in RAW 264.7 cells via suppression of NF-κB activation

•Calcium citrate suppressed the activation of NF-κB.•Calcium citrate decreased expression of iNOS and COX-2.•Calcium citrate inhibited expression of pro-inflammatory cytokines.•Thus, Calcium citrate could be useful as a good anti-inflammatory agent.

Here we aimed to investigate the anti-inflammatory effects of calcium citrate in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. The anti-inflammatory effects of calcium citrate were investigated by assessing pro-inflammatory factors (NO, ROS, NF-κB, iNOS, and COX-2) and pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α). Treatment of cells with calcium citrate (10–100 μM) significantly reduced the generation of intracellular reactive oxygen species and increased the activities of the antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase in LPS-stimulated macrophages. Calcium citrate was further shown to inhibit NO production in LPS-stimulated RAW 264.7 cells. The expression levels of iNOS, COX-2, and NF-κB were also suppressed by treatment with calcium citrate. Calcium citrate was furthermore found to significantly inhibit the production of IL-1β, IL-6, and TNF-α in response to LPS-stimulation. These findings demonstrate that calcium citrate may be an effective anti-inflammatory agent.