C-phycocyanin reduces inflammation by inhibiting NF-κB activity through downregulating PDCD5 in lipopolysaccharide-induced RAW 264.7 macrophages

C-phycocyanin (C-PC), a type of functional food colourant, plays a significant role in regulating inflammatory responses. However, its underlying anti-inflammatory mechanism remains unknown. Previously, we have established a S-35 in vivo/vitro labelling analysis for dynamic proteomic (SiLAD) technology. Unlike traditional proteomic methods, SiLAD exclusively detects synthesis rates instead of accumulated amounts through 35S pulse labelling of newly synthesized proteins, providing a high sensitive way for analysing protein alterations. In this work, we applied SiLAD to explore the anti-inflammatory mechanism of C-PC. We found that the protein synthesis rates were specifically detected and visualised. Strikingly, network analysis suggested programmed cell death 5 protein (PDCD5) was involved in C-PC mediated anti-inflammatory process. Phenotyping experiments demonstrated that C-PC could reduce inflammation through down-regulating PDCD5-NF-kappa B signaling. These results provided important information for the regulation of C-PC, and offered a novel perspective for regulatory mechanism of functional food.