Anti-Inflammatory Effects of Chloranthalactone B in LPS-Stimulated RAW264.7 Cells

Abstract

Chloranthalactone B (CTB), a lindenane-type sesquiterpenoid, was obtained from the Chinese medicinal herb Sarcandra glabra, which is frequently used as a remedy for inflammatory diseases. However, the anti-inflammatory mechanisms of CTB have not been fully elucidated. In this study, we investigated the molecular mechanisms underlying these effects in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. CTB strongly inhibited the production of nitric oxide and pro-inflammatory mediators such as prostaglandin E2, tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and IL-6 in RAW264.7 cells stimulated with LPS. A reverse-transcription polymerase chain reaction assay and Western blot further confirmed that CTB inhibited the expression of inducible nitric oxide synthase, cyclooxygenase-2, TNF-α, and IL-1β at the transcriptional level, and decreased the luciferase activities of activator protein (AP)-1 reporter promoters. These data suggest that inhibition occurred at the transcriptional level. In addition, CTB blocked the activation of p38 mitogen-activated protein kinase (MAPK) but not c-Jun N-terminal kinase or extracellular signal-regulated kinase 1/2. Furthermore, CTB suppressed the phosphorylation of MKK3/6 by targeting the binding sites via formation of hydrogen bonds. Our findings clearly show that CTB inhibits the production of inflammatory mediators by inhibiting the AP-1 and p38 MAPK pathways. Therefore, CTB could potentially be used as an anti-inflammatory agent.

Anti-Inflammatory Potential of Carpomitra costata Ethanolic Extracts via Inhibition of NF-κB and AP-1 Activation in LPS-Stimulated RAW264.7 Macrophages

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Isoacteoside, a dihydroxyphenylethyl glycoside, exhibits anti‐inflammatory effects through blocking toll‐like receptor 4 dimerization

“…Many studies have shown that RAW264.7 cells do not produce mature IL‐1β (Chujor et al , ; Ndengele et al , ). However, numerous other authors have reported that according to ELISA, LPS stimulation of RAW264.7 cells could lead to IL‐1β release (Shin et al , ; Li et al , ; Xiang et al , ). Thus, we evaluated IL‐1β expression using Western blotting.…”

Intracellular synthesis of gold nanoparticles by Gluconacetobacter liquefaciens for delivery of peptide CopA3 and ginsenoside and anti-inflammatory effect on lipopolysaccharide-activated macrophages

“…Macrophages are the primary contributors to the initiation of potentially pathological inflammation and the progression of autoimmune and auto-inflammatory diseases including cancer, rheumatoid arthritis, cardiovascular disease, atherosclerosis, and Alzheimer's disease [41]. In the early phase of a disease, the innate immune system and Toll-like receptor (TLR) signalling can recognise and respond to diverse microbial epitope pathogen-associated molecular patterns such as LPS [42].…”