Flavonoids derived from Exocarpium Citri Grandis inhibit LPS-induced inflammatory response via suppressing MAPK and NF-κB signalling pathways

Abstract

Pan (2019) Flavonoids derived from ExocarpiumCitriGrandis inhibit LPS-induced inflammatory response via suppressing MAPK and NF-κB signalling pathways, Food and Agricultural Immunology, 30:1, 564-580, ABSTRACT Exocarpium Citri Grandis (ECG) is used as an antitussive and antiinflammatory agent in traditional Chinese medicine. However, the mechanism of its anti-inflammatory effect remains unknown. In this study, flavonoids of ECG (FECG) were extracted to investigate the anti-inflammatory effect using a RAW264.7 macrophage model. The results suggested that FECG could remarkably inhibit the production of nitric oxide (NO). Meanwhile, FECG decreased the mRNA and protein expression of inflammatory cytokines including tumour necrosis factor alpha (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6), while showed an opposite effect on interleukin-10 (IL-10). Furthermore, FECG suppressed the phosphorylation of p38 (p38 kinase), JNK (c-Jun N-terminal kinase), ERK (extracellular signal-regulated kinase) and NF-κB. Taken together, our results indicated that FECG might regulate the activation of MAPK and NF-κB signalling pathways to exert anti-inflammatory effects. This study provides some insights into the mechanism underlying the anti-inflammatory activity of ECG, which may facilitate a better application of ECG. ARTICLE HISTORY

Bisbenzylisoquinoline alkaloids of lotus ( Nelumbo nucifera Gaertn.) seed embryo inhibit lipopolysaccharide-induced macrophage activation via suppression of Ca 2+ -CaM/CaMKII pathway

“…Nuclear factor (NF)-κB plays a prominent role in inflammation. Activation of NF-κB depends on IκB phosphorylation and subsequent separation from NF-κB (Peng et al, 2019). The liberated NF-κB is considered to regulate the transcription of inducible enzymes and inflammatory cytokines, such as inducible nitric oxide synthase (iNOS), IL-1β, IL-6 and TNF-α (Baeuerle & Henkel, 1994).…”

Bilberry anthocyanin-rich extract protects against retinal photooxidative damage via activation of HO-1 and inhibition of NF-κB

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Research Progress on Chemical Composition and Pharmacological Action of Exocarpium Citri Grandis

“…The main active ingredients of ECG are flavonoids, the most important of which are naringin and rhoifolin, the sum of which accounts for more than 84% of the total flavonoids in ECG. It has antioxidant, anti-inflammatory, anti-cancer, liver protection, regulation of cardiovascular and cerebrovascular diseases and fat metabolism effects [3][4][5][6][7]. Liu Qundi et al attributed several flavonoids such as naringin, rhoifolin, naringienin and apigenin by HPLC-DAD-MS/MS analysis.…”