Investigation of constituents from Cinnamomum camphora (L.) J. Presl and evaluation of their anti-inflammatory properties in lipopolysaccharide-stimulated RAW 264.7 macrophages.

Abstract

ETHNOPHARMACOLOGY RELEVANCE:

Cinnamomum camphora (L.) J. Presl has been used for the traditional medicine as a therapeutic agent of inflammation-related diseases, including sprains, rheumatic arthritis, abdominal pain, cough and bronchitis, for a long history. The aim of the present study was to illustrate anti-inflammatory substances of C. camphora and their mechanism of action, and to establish the correlations between chemical constituents and traditional uses of this plant.

MATERIALS AND METHODS:

Chemical constituents were purified by chromatographic methods, and their structures were established based on spectroscopic analysis. Lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages was adopted for evaluating the anti-inflammatory activity in vitro. The nitric oxide (NO) production assay and nuclear factor kappa B (NF-κB) dual luciferase reporter assay were used to screen anti-inflammatory constituents. The mRNA and protein levels of inflammation-related cytokines and enzymes were determined by real-time reverse transcription-polymerase chain reaction (RT-PCR), immunoblot analysis, and enzyme linked immunosorbent assay (ELISA), respectively.

RESULTS:

Twenty-five constituents were isolated from the EtOH extract of C. camphora. Eight constituents, covering phenylpropanoid (7), lignans (10 and 22), flavonoids (16-18), coumarin (21), and terpenoid (24) significantly inhibited LPS-stimulated NO production with maximum inhibition rates (MIRs) of ≥ 80%, and thus were verified to be the anti-inflammatory substances of this ethnomedical plant. (+)-Episesaminone (SMO, 22) and 3S-(+)-9-oxonerolidol (NLD, 24) blocked NF-κB activation via inducing IκBα expression. Moreover, SMO and NLD inhibited productions of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and prostaglandin E2 (PGE2), and alleviated increased mRNA and protein levels of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX-2), and matrix metallopeptidase-9 (MMP-9) in LPS-stimulated RAW 264.7 macrophages.

CONCLUSIONS:

The ethnomedical use of C. camphora for the treatment of inflammation-related diseases was attributed to the combined in vitro anti-inflammatory activities of phenylpropanoid, lignan, flavonoid, coumarin, and terpenoid. SMO and NLD were found to be new molecules with in vitro anti-inflammatory activities, which are achieved by inhibiting NF-κB regulated inflammatory response.

• Authors: Yan-Ru Li, Chun-Sheng Fu, Wen-Jing Yang, Xiao-Ling Wang, Dan Feng, Xiao-Ning Wang, Dong-Mei Ren, Hong-Xiang Lou, Tao Shen
• Journal: Journal of ethnopharmacology (J Ethnopharmacol) Vol. 221 Pg. 37-47 (Jul 15 2018) ISSN: 1872-7573 [Electronic] Ireland
• PMID: 29660467 (Publication Type: Journal Article)
• Copyright: Copyright © 2018 Elsevier B.V. All rights reserved.

Chemical References

• Anti-Inflammatory Agents
• Cytokines
• Lipopolysaccharides
• NF-kappa B
• Phytochemicals
• Plant Extracts
• Nitric Oxide
• Nitric Oxide Synthase Type II
• Nos2 protein, mouse
• Ptgs2 protein, mouse
• Cyclooxygenase 2

Topics

• Animals
• Anti-Inflammatory Agents (analysis, pharmacology)
• Cell Survival (drug effects)
• Cinnamomum camphora
• Cyclooxygenase 2 (genetics)
• Cytokines (genetics, metabolism)
• Lipopolysaccharides (pharmacology)
• Macrophages (drug effects, metabolism)
• Mice
• NF-kappa B (metabolism)
• Nitric Oxide (metabolism)
• Nitric Oxide Synthase Type II (genetics)
• Phytochemicals (analysis, pharmacology)
• Plant Components, Aerial
• Plant Extracts (analysis)
• RAW 264.7 Cells