GTS-21 attenuates lipopolysaccharide-induced inflammatory cytokine production in vitro by modulating the Akt and NF-κB signaling pathway through the α7 nicotinic acetylcholine receptor.

Abstract

OBJECTIVE:

GTS-21, a selective α7 nicotinic acetylcholine receptor agonist, has recently been established as a promising treatment for inflammation. However, the detailed molecular mechanism of GTS-21 in suppressing pro-inflammatory cytokine production is only partially explored. The study aimed to analyze cytokine expression suppressed by GTS-21 with lipopolysaccharide (LPS)-induced inflammation in vitro and to gain insights into the role of Akt/NF-κB signaling pathway in this process.

MATERIALS AND METHODS:

Cell Counting Kit-8 (CCK-8) assay was performed to detect drug cytotoxicity. RAW 264.7 cells were stimulated with LPS and treated with GTS-21. Interleukin (IL)-1β, IL-6, or tumor necrosis factor (TNF)-α production was detected using enzyme-linked immunosorbent assay. Western blot was used to assess the expression patterns of signal transduction protein. Nuclear translocation of nuclear factor (NF)-κB was analyzed by confocal fluorescence microscopy. In addition, α7 nicotinic acetylcholine receptors (α7 nAChR) were detected on RAW264.7, and the α7 nAChR-specific antagonist was adopted to verify whether the effect of GTS-21 was mediated by α7 nAChR.

RESULTS:

The CCK-8 assay showed that GTS-21 did not significantly affect cell proliferation. The production of IL-1β, IL-6, and TNF-α decreased after being treated with GTS-21 in LPS-stimulated RAW 264.7 cells. GTS-21 also suppressed LPS-induced phosphorylation of NF-κBp65, IKKα/β, IκBα, and Akt, as well as NF-κB p65 nuclear translocation. Moreover, α7 nAChR was expressed on the surfaces of RAW264.7 cells, and the α7 nAChR-specific antagonist almost completely prohibited the inhibitory effect of GTS-21 on NF-κB activation.

CONCLUSION:

These findings indicate that GTS-21 suppresses LPS-induced inflammation by inhibiting the Akt/NF-κB signal pathway through α7 nAChR. GTS-21 has a potential application in inflammatory disease therapy.

• Authors: Ye Yue, Ruoxi Liu, Wenxiang Cheng, Yiping Hu, Jinchao Li, Xiaohua Pan, Jiang Peng, Peng Zhang
• Journal: International immunopharmacology (Int Immunopharmacol) Vol. 29 Issue 2 Pg. 504-512 (Dec 2015) ISSN: 1878-1705 [Electronic] Netherlands
• PMID: 26490221 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2015. Published by Elsevier B.V.

Chemical References

• Benzylidene Compounds
• Bungarotoxins
• Coumarins
• Cytokines
• Lipopolysaccharides
• NF-kappa B
• Nicotinic Antagonists
• Pyridines
• alpha7 Nicotinic Acetylcholine Receptor
• coumarin-alpha-bungarotoxin conjugate
• 3-(2,4-dimethoxybenzylidene)anabaseine
• Oncogene Protein v-akt

Topics

• Animals
• Benzylidene Compounds (pharmacology)
• Bungarotoxins (pharmacology)
• Coumarins (pharmacology)
• Cytokines (biosynthesis)
• Inflammation (metabolism)
• Lipopolysaccharides (pharmacology)
• Mice
• NF-kappa B (biosynthesis, genetics)
• Nicotinic Antagonists (pharmacology)
• Oncogene Protein v-akt (biosynthesis, genetics)
• Pyridines (pharmacology)
• RAW 264.7 Cells
• Signal Transduction (drug effects)
• alpha7 Nicotinic Acetylcholine Receptor (drug effects)