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Cecropin B Represses CYP3A29 Expression through Activation of the TLR2/4-NF-κB/PXR Signaling Pathway

Xiaoqiao Zhou1, Xiaowen Li1, Xiliang Wang1

  • 1State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, P.R. China.

Scientific Reports
|June 15, 2016
PubMed

Insights

Cecropin B peptide antibiotics inhibit CYP3A29 expression by activating Toll-like receptors (TLRs) and NF-κB signaling. This pathway disrupts PXR/RXR-α complex binding, downregulating CYP3A29.

Area of Science:

  • Pharmacology
  • Molecular Biology
  • Immunology

Background:

  • Cecropins are peptide antibiotics with applications as drugs and feed additives.
  • Cecropin B is known to inhibit CYP3A29 expression, but the mechanism is not fully understood.

Purpose of the Study:

  • To elucidate the molecular mechanisms by which cecropin B affects CYP3A29 expression.
  • To investigate the roles of Toll-like receptors (TLRs) and NF-κB pathways in this process.

Main Methods:

  • Investigated the effects of cecropin B on CYP3A29 expression in pig liver cells.
  • Analyzed the involvement of pregnane X receptor (PXR), retinoid X receptor alpha (RXR-α), and NF-κB signaling.
  • Examined the interaction of cecropin B with TLRs 2 and 4.

Main Results:

  • Cecropin B dose- and time-dependently inhibited CYP3A29 expression.
  • NF-κB activation by cecropin B disrupted the PXR/RXR-α complex binding to DNA.
  • NF-κB p65 directly interacted with PXR, suppressing its transactivation and leading to CYP3A29 downregulation.
  • Cecropin B activated TLRs 2 and 4, modulating NF-κB signaling.

Conclusions:

  • Cecropin B inhibits CYP3A29 expression through a TLR/NF-κB/PXR-dependent pathway.
  • These findings are crucial for the future development of cecropins and other antimicrobial peptides.

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