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Leucomycin A3, a 16-membered macrolide antibiotic, inhibits influenza A virus infection and disease progression

Ryuichi Sugamata1, Akihiro Sugawara2, Tomokazu Nagao1

  • 11] Inflammation Program, Graduate School of Medicine, Chiba University, Chiba City, Japan [2] Department of Immunology, National Institute of Infectious Diseases, Shinjuku-ku, Japan.

The Journal of Antibiotics
|February 6, 2014
PubMed

Insights

Leucomycin A3 (LM-A3) significantly improved survival rates in mice with lethal influenza A virus infection by reducing lung damage and viral load. This macrolide derivative shows promise as a novel antiviral drug candidate.

Area of Science:

  • Virology
  • Immunology
  • Pharmacology

Background:

  • Severe influenza virus infections lead to high fatality rates.
  • Neutrophil myeloperoxidase (MPO) contributes to severe influenza-induced pneumonia by releasing tissue-damaging factors.
  • Identifying novel anti-influenza compounds is crucial for effective treatment.

Purpose of the Study:

  • To screen macrolide compounds, including leucomycin A3 (LM-A3), for their ability to inhibit MPO release and combat influenza A virus infection.
  • To evaluate the therapeutic potential of LM-A3 and related macrolides in a lethal influenza virus mouse model.
  • To investigate the dissociation of antibacterial and antiviral activities in macrolide derivatives.

Main Methods:

  • Screening of LM-A3, spiramycin (SPM), erythromycin derivative EM900, and clarithromycin (CAM) for inhibition of MPO release in mouse and human neutrophils.
  • In vivo studies involving lethal A/H1N1 influenza virus (PR-8) infection in mice treated with candidate compounds.
  • In vitro assessment of antiviral activity against influenza A virus in human A549 epithelial cells.

Main Results:

  • LM-A3 demonstrated the highest survival rate (80.9%) in mice infected with lethal influenza A virus.
  • LM-A3 treatment beneficially affected lung pathology, reduced viral proliferation, and modulated MPO release, pro-inflammatory cytokines, and interferon-α production.
  • SPM and EM900 also showed positive survival effects, while CAM did not; all tested compounds inhibited virus proliferation in vitro.
  • EM900's efficacy suggests that antibacterial and antiviral activities can be pharmacologically separated in macrolide derivatives.

Conclusions:

  • LM-A3 is a promising lead compound for developing new anti-influenza drugs due to its high antiviral activity and beneficial effects on host response.
  • Novel macrolide derivatives can be developed with potent antiviral properties independent of antibacterial activity.
  • This research provides a basis for novel macrolide-based antiviral therapies against influenza.

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