Olea europaea L. leaf extract mitigates pulmonary inflammation and tissue destruction in Wistar rats induced by concurrent exposure to noise and toluene

Abstract

This study aimed to investigate the effects of combined exposure to noise (85 dB(A)) and inhaled Toluene (300 ± 10 ppm) on rat lung health. It also aimed to assess the potential therapeutic effects of Olea europaea L. leaves extract (OLE) (40 mg/kg/day) using biochemical, histopathological, and immunohistochemical (IHC) analyses, as well as determination of pro-inflammatory cytokines (TNF-α and IL-1β), and in silico Docking studies. The experiment involved forty-two male Wistar rats divided into seven groups, each exposed to a 6-week/6-hour/day regimen of noise and Toluene. The groups included a control group, rats co-exposed to noise and Toluene, and rats co-exposed to noise and Toluene treated with OLE for different durations. The results indicated that noise and Toluene exposure led to structural damage in lung tissue, oxidative harm, and increased levels of pro-inflammatory cytokines (TNF-α and IL-1β). However, the administration of OLE extract demonstrated positive effects in mitigating these adverse outcomes. OLE treatment reduced lipid peroxidation and enhanced the activities of catalase and superoxide dismutase, indicating its anti-oxidant properties. Furthermore, OLE significantly decreased the levels of pro-inflammatory cytokines compared to the groups exposed to noise and Toluene without OLE treatment. Moreover, the in silico investigation substantiated a robust affinity between COX-2 and OLE components, affirming the anti-inflammatory activity. Overall, our findings suggest that OLE possesses anti-inflammatory and anti-oxidative properties that mitigate the adverse effects of concurrent exposure to noise and Toluene.

Graphical abstract

Keywords:

• Noise and toluene
• lung tissue
• Olea Europaea L. leaf extract
• rat
• anti-oxidant activity
• cytokine

Acknowledgement

We gratefully acknowledge support from the quality control laboratory of the Herbs of Tunisia Company in El Mansoura, Siliana, and Dr. Sana BAHRI for providing the Olea europea L. leaf extract.

We thank the Department of Pathology, Charles Nicolle Hospital, Tunis, Tunisia.

We would also like to acknowledge the support and cooperation of the experimental medicine unit’s Faculty of Medicine of Tunis team in carrying out this work.

Disclosure statement

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

Data availability statement

All data and materials essential for supporting the conclusions of this study are incorporated within the article and can be made available upon request.

Additional information

Funding

The authors declare that no funds, grants, or other support were received during the preparation of this manuscript.