Gold nanoflowers synthesized using Acanthopanacis cortex extract inhibit inflammatory mediators in LPS-induced RAW264.7 macrophages via NF-κB and AP-1 pathways

Abstract

We reported the rapid synthesis (<8s) of gold nanoparticles at room temperature using Acanthopanacis cortex extract (A-AuNPs). We characterized the A-AuNPs using several analytical techniques and found that nano-flower type A-AuNPs, which are known to possess a coarse surface with a high surface to volume ratio, conferring these particles with high binding capacity for various biological molecules. After confirming the stability of the nanoparticles, we investigated the anti-inflammatory effect of A-AuNPs in LPS-stimulated RAW264.7 cells. These nanoparticles inhibited LPS-induced iNOS and COX-2 protein as well as gene expression level, along with reduction of NO and PGE₂ production. Furthermore, we observed that the A-AuNPs inhibited translocation of NF-κB and AP-1 through phosphorylation of MAPK signaling by western blot analysis. In summary, we synthesized gold nanoflowers in an economical and eco-friendly way using Acanthopanacis cortex extract and the resultant flower-like A-AuNPs had anti-inflammatory activity, highlighting their potential as therapeutic candidates for suppression of inflammatory-mediated diseases.

Keywords: Acanthopanacis cortex; Gold nanoflowers; Green synthesis; Inflammation.