Antibacterial potential of Euphorbia canariensis against Pseudomonas aeruginosa bacteria causing respiratory tract infections

Abstract

The widespread dissemination of bacterial resistance has led to great attention being paid to finding substitutes for traditionally used antibiotics. Plants are rich in various phytochemicals that could be used as antibacterial therapies. Here, we elucidate the phytochemical profile of Euphorbia canariensis ethanol extract (EMEE) and then elucidate the antibacterial potential of ECEE against Pseudomonas aeruginosa clinical isolates. ECEE showed minimum inhibitory concentrations ranging from 128 to 512 µg/mL. The impact of ECEE on the biofilm-forming ability of the tested isolates was elucidated using crystal violet assay and qRT-PCR to study its effect on the gene expression level. ECEE exhibited antibiofilm potential, which resulted in a downregulation of the expression of the biofilm genes (algD, pelF, and pslD) in 39.13% of the tested isolates. The antibacterial potential of ECEE was studied in vivo using a lung infection model in mice. A remarkable improvement was observed in the ECEE-treated group, as revealed by the histological and immunohistochemical studies. Also, ELISA showed a noticeable decrease in the oxidative stress markers (nitric oxide and malondialdehyde). The gene expression of the proinflammatory marker (interleukin-6) was downregulated, while the anti-inflammatory biomarker was upregulated (interleukin-10). Thus, clinical trials should be performed soon to explore the potential antibacterial activity of ECEE, which could help in our battle against resistant pathogenic bacteria.

Graphical Abstract

Keywords:

• Lung infection
• biofilm
• qRT-PCR
• inflammatory markers
• LC/ms
• oxidative stress

Acknowledgments

This work was funded by the Deanship of Scientific Research at Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia, through the Research Groups Program Grant no. (RGP-1443-0044). The authors, therefore, gratefully acknowledge the DSR technical and financial support.

Informed consent statement

Not applicable.

Institutional review board statement

All standard procedures of handling of laboratory animals were followed and the experiment protocol was approved by the research ethical committee of faculty of pharmacy, Tanta University, Egypt (TP/RE/5/23 p-0024).

Author’s contribution

BA: conceptualisation, data curation, methodology, and formal analysis, EE: conceptualisation, data curation, formal analysis, methodology, writing original draft, and editing. TAE: methodology, writing original draft and revision and editing, AS: methodology, writing original draft and revision and editing, MEA: investigation, methodology, and writing original draft, KNA: data curation, methodology, writing original draft, and formal analysis, WAN: conceptualisation, data curation, formal analysis, methodology, writing original draft, and editing. All authors have read and agreed to the published version of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

All data that support the finding displayed in our study are included in the manuscript. Any further data is available upon request.

Additional information

Funding

This work was funded by the Deanship of Scientific Research at Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia, through the Research Groups Program Grant no. (RGP-1443-0044). The authors, therefore, gratefully acknowledge the DSR technical and financial support.