Anti-inflammatory Activity of Baicalein in LPS-Stimulated RAW264.7 Macrophages via Estrogen Receptor and NF-κB-Dependent Pathways

• DOI: 10.1007/s10753-013-9703-2
• Publication Date: 2013-07-27T08:40:15Z
• Authors: Guan-Wei Fan; Yuan Zhang; Xiaorui Jiang; Yan Zhu; Bingyao Wang; Lina Su; Wenjie Cao; Han Zhang; Xiumei Gao
• Keywords: Lipopolysaccharides; 0303 health sciences; Macrophages; Interleukin-1beta; Anti-Inflammatory Agents; NF-kappa B; Nitric Oxide Synthase Type II; Nitric Oxide; Dinoprostone; Cell Line; 3. Good health; Mice; 03 medical and health sciences; NF-KappaB Inhibitor alpha; Cyclooxygenase 2; Flavanones; Animals; Humans; I-kappa B Proteins; RNA, Messenger; Medicine, Chinese Traditional; Phosphorylation; HeLa Cells

Baicalein has been used for many years as a popular antiviral and antibacterial in China. Recent investigations revealed that baicalein also has anti-inflammatory activities. Our results indicated that baicalein increases ERE-luciferase activity in an estrogen receptor (ER)-dependent manner when either ERα or ERβ were coexpressed in Hela cells. This study examined whether baicalein exerts an anti-inflammatory effect in RAW264.7 cells through an estrogen receptor-dependent pathway and through regulation of NF-ĸB activation. In lipopolysaccharide (LPS)-induced RAW264.7 cells, baicalein exerts anti-inflammatory effects by inhibiting iNOS, COX-2, and TNF-α mRNA expression; NO production; as well as inflammatory cytokine (IL-1β, PGE2, and TNF-α) production through an ER-dependent pathway. These effects are accompanied with the inhibition of the transcription factor NF-ĸB activation and IκBα phosphorylation. We therefore conclude that baicalein inhibits LPS-induced inflammatory cytokine production via regulation of the NF-ĸB pathway and estrogen-like activity, suggesting that it may be useful for preventing inflammation-related diseases.