Anti-Inflammatory and Antioxidant Effects of Anthocyanins of(Red Clover) in Lipopolysaccharide-Stimulated RAW-267.4 Macrophages.
Nutrients. 2020 Apr 15 ;12(4). Epub 2020 Apr 15. PMID: 32326385
Sang Gil Lee
Red clover () possesses various dietary compounds that improve human health. However, the functions of anthocyanins in red clover remain unclear. Here we examined anti-inflammatory and antioxidant effects of red clover extract (RC) and red clover anthocyanins fraction (RCA) using lipopolysaccharide (LPS)-treated RAW 264.7 macrophages and identified dietary compounds. RC and RCA suppressed LPS-induced expression of genes such as tumor necrosis factor (), interleukin (), inducible nitric oxide synthase (), monocyte chemoattractant protein ()1, and cyclooxygenase (). LPS-stimulated intracellular reactive oxygen species (ROS) production also was prevented by both RC and RCA. NADPH oxidase 1 (NOX1) gene and phosphorylation of p47of NOX1 that were increased by LPS were inhibited in the cells treated with RCA. LPS-stimulated nuclear factor erythroid 2-related factor 2 () gene expression and nuclear translocation of nuclear factor kappa B (NF-kB) subunit p65 were suppressed together with reduced iNOS and COX2 proteins by RCA. Additionally, 27 polyphenols and 7 anthocyanins from RC were identified and quantified. In conclusion, RC, especially RCA, exerted anti-inflammatory and anti-oxidative activities in vitro by regulating NF-κB and NRF2 signaling pathways, suggesting that anthocyanins in red clover are the potential candidates to reduce inflammation and oxidative stress.