Selenium-enriched oolong tea (Camellia sinensis) extract exerts anti-inflammatory potential via targeting NF-κB and MAPK pathways in macrophages
Qi Wang, Juqing Huang, Yafeng Zheng, Xuefang Guan, Chenchun Lai, Huiying Gao, Chi‐Tang Ho, Bin Lin
Abstract
Both tea polyphenols and selenium (Se) have been suggested to exert the health benefits via the regulatory capacities of chronic inflammation, which make Se-enriched oolong tea a promising beverage as an anti-inflammatory diet. The aim of this study is to investigate the anti-inflammatory effects of Se-enriched oolong tea extract (Se-TE) and underlying mechanism in lipopolysaccharide (LPS)-induced RAW264.7 cells. Se-TE treatments (50 and 150 μg/mL) significantly suppressed the over-production of nitric oxide (NO) and prostaglandin E2 (PGE2) in LPS-stimulated macrophages via downregulating the expression of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Moreover, Se-TEs also effectively inhibited the productions of inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β). Furthermore, Se-TE could block mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) signaling pathways through the inhibition of the phosphorylation of key proteins (IκB-α, p65, p38, ERK, and JNK) and the translocation of the p65 subunit into the nucleus. Collectively, our results indicated that Se-TE may have the potential to be used as a novel food ingredient for the development of various anti-inflammatory foods and the treatment and prevention of chronic inflammation-related diseases.