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  3. The flavonoid-enriched extract from the root of Smilax china L. inhibits inflammatory responses via the TLR-4-mediated signaling pathway

The flavonoid-enriched extract from the root of Smilax china L. inhibits inflammatory responses via the TLR-4-mediated signaling pathway

  • J Ethnopharmacol. 2020 Jun 28;256:112785. doi: 10.1016/j.jep.2020.112785.
Haixing Feng 1,  Yanling He 2,  Lei La 3,  Chuqi Hou 4,  Luyao Song 5,  Qin Yang 6,  Fuling Wu 7,  Wenqin Liu 8,  Lianbing Hou 9,  Yan Li 10,  Chunxia Wang 11,  Yuhao Li 12
Affiliations

Affiliations

  • 1 Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China. Electronic address: [email protected].
  • 2 Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China; Department of Pharmacy, Guangzhou Women and Children's Medical Center, Guangzhou, 510623, China. Electronic address: [email protected].
  • 3 Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China. Electronic address: [email protected].
  • 4 School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, 510515, China. Electronic address: [email protected].
  • 5 Department of Pharmacy, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China. Electronic address: [email protected].
  • 6 Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China. Electronic address: [email protected].
  • 7 Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China. Electronic address: [email protected].
  • 8 Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China. Electronic address: [email protected].
  • 9 Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China; Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, 510515, China. Electronic address: [email protected].
  • 10 Endocrinology and Metabolism Group, Sydney Institute of Health Sciences/Sydney Institute of Traditional Chinese Medicine, Sydney, NSW, 2000, Australia. Electronic address: [email protected].
  • 11 Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China; Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, 510515, China. Electronic address: [email protected].
  • 12 Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China; Endocrinology and Metabolism Group, Sydney Institute of Health Sciences/Sydney Institute of Traditional Chinese Medicine, Sydney, NSW, 2000, Australia. Electronic address: [email protected].
PMID: 32222576 DOI: 10.1016/j.jep.2020.112785
Abstract

Ethnopharmacological relevance: Smilax china L. has been used clinically to treat various inflammatory disorders with a long history.

Aim of the study: To investigate the mechanisms underlying anti-inflammatory action of the extract from the herb.

Materials and methods: The extract was identified and quantified using the Ultra Performance Liquid Chromatography-Photo Diode Array-Mass Spectrometer method. The anti-inflammatory activities were examined in xylene-induced mouse ear edema and cotton ball-induced rat granuloma. The inflammatory mediators, pro-inflammatory cytokines and TLR-4-mediated signals in LPS-stimulated RAW264.7 macrophages were determined using ELISA, Real-Time PCR, Western blot and/or immunofluorescence, respectively.

Results: The extract was found to enrich Flavonoids (44.3%, mainly astilbin, engeletin, isoastilbin, cinchonain Ia, quercetin-3-O-a-L-rhamnopyranoside and chlorogenic acid). The flavonoid-enriched extract (FEE) inhibited xylene-induced mouse ear edema and cotton ball-induced rat granuloma, and suppressed LPS-induced over-release and/or overexpression of tumor necrosis factor-α, cyclooxygenase-2, inducible nitric oxide synthase, interleukin-1β and interleukin-6 in RAW264.7 macrophages. Mechanistically, FEE suppressed protein overexpression of TLR-4 and its downstream signals, MyD88 protein, phosphorylated inhibitory κB-α, NF-κB-P65 and MAPK p38, as well as phosphorylation of phosphoinositide 3-kinase (PI3K) p85α at Tyr607 and Akt at Ser473 in LPS-stimulated macrophages. The mode of the anti-inflammatory action of FEE was similar to that of TAK-242 (a selective TLR-4 inhibitor).

Conclusions: The present results demonstrate that FEE inhibit inflammatory responses via the TLR-4-mediated signaling pathway. Our findings go a new insight into the mechanisms underlying anti-inflammatory action of the herb, and provide a better understanding of its use for inflammatory diseases.

Keywords

Flavonoids; Inflammation; Smilax china L.; TLR-4.

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