title: Ginsenoside Rh2 Downregulates LPS-Induced NF- κ B Activation through Inhibition of TAK1 Phosphorylation in RAW 264.7 Murine Macrophage.
abstract: The present study was carried out to evaluate the inhibitory effects of ginsenoside Rh2 on nuclear-factor- (NF-) κ B in lipopolysaccharide- (LPS-) activated RAW 264.7 murine macrophages. RAW 264.7 cells were pretreated with indicated concentrations of ginsenoside Rh2 for 1 h prior to the incubation of LPS (1  μ g/mL) for indicated time period. Ginsenoside Rh2 reduced CD14 and Toll-like receptor 4 (TLR4) expressions 24 h after LPS stimulation. Furthermore, ginsenoside Rh2 significantly inhibited TGF-beta-activated kinase 1 (TAK1) phosphorylation 30 min after LPS stimulation. Ginsenoside Rh2 was further shown to inhibit NF- κ B p65 translocation into the nucleus by suppressing I κ B- α degradation. Also, LPS increased mRNA expression of TNF- α and IL-1 α time-dependently, while TQ reduced TNF- α within 3 h and IL-1 α within 1 h. And we firstly found that pretreatment of ginsenoside Rh2 successively inhibited hypoxia-inducible factor- (HIF-) 1 α expression increased by LPS. In conclusion, ginsenoside Rh2 may inhibit LPS-induced NF- κ B activation and reduce HIF-1 α accumulation, suggesting that ginsenoside Rh2 may be considered as a potential therapeutic candidate for chronic inflammatory diseases.
authors.affiliation: Key Laboratory of Natural Resource of Changbai Mountain and Functional Molecules, College of Pharmacy, Yanbian University, Ministry of Education, Yanji, Jilin 133002, China.
authors.forename: Li-Hua
authors.initials: LH
authors.lastname: Lian
authors.forename: Quan
authors.initials: Q
authors.lastname: Jin
authors.forename: Shun-Zong
authors.initials: SZ
authors.lastname: Song
authors.forename: Yan-Ling
authors.initials: YL
authors.lastname: Wu
authors.forename: Ting
authors.initials: T
authors.lastname: Bai
authors.forename: Shuang
authors.initials: S
authors.lastname: Jiang
authors.forename: Qian
authors.initials: Q
authors.lastname: Li
authors.forename: Ning
authors.initials: N
authors.lastname: Yang
authors.forename: Ji-Xing
authors.initials: JX
authors.lastname: Nan