Eugenol protects against Aspergillus fumigatus keratitis by inhibiting inflammatory response and reducing fungal load.

Abstract

Fungal keratitis is a corneal infection, which severely impairs vision. The fungal pathogen provokes host immune response, but the excessive inflammatory response causes significant collateral damage to the cornea. Eugenol, the main component of clove oil, has been found to have a broad range of pharmacological activities including anti-microbial, antioxidation and anti-inflammation. However, the role of eugenol in Aspergillus fumigatus (A. fumigatus) keratitis is unknown. In this study, we demonstrated that eugenol reduced mice keratitis severity, inflammatory cells infiltration, pro-inflammatory cytokine expression, and the fungal load. Eugenol also decreased the expressions of pro-inflammatory cytokines in human corneal epithelial cells (HCECs). We confirmed that the anti-inflammatory effects of eugenol were related to activating nuclear factor erythroid 2-related factor 2/Heme Oxygenase-1 (Nrf2/HO-1) signaling pathway. Moreover, we demonstrated that eugenol could inhibit the A. fumigatus growth and adhesion to host cells, as well as damage the fungal biofilm. The antifungal mechanism seemed to be disrupting the integrity of the fungal membrane and reducing the biosynthesis of ergosterol. Taken together, our research suggested that eugenol exerted protective effects on mouse A. fumigatus keratitis, due to its anti-inflammatory and antifungal activity.

• Authors: Bing Yu, Cui Li, Lingwen Gu, Lina Zhang, Qian Wang, Yan Zhang, Jing Lin, Liting Hu, Yiyi Jia, Min Yin, Guiqiu Zhao
• Journal: European journal of pharmacology (Eur J Pharmacol) Vol. 924 Pg. 174955 (Jun 05 2022) ISSN: 1879-0712 [Electronic] Netherlands
• PMID: 35436473 (Publication Type: Journal Article)
• Copyright: Copyright © 2022 Elsevier B.V. All rights reserved.

Chemical References

• Anti-Inflammatory Agents
• Antifungal Agents
• Cytokines
• Eugenol

Topics

• Animals
• Anti-Inflammatory Agents (pharmacology, therapeutic use)
• Antifungal Agents (pharmacology, therapeutic use)
• Aspergillosis (drug therapy, metabolism, microbiology)
• Aspergillus fumigatus (physiology)
• Cytokines (metabolism)
• Eugenol (pharmacology, therapeutic use)
• Keratitis (drug therapy, metabolism, microbiology)
• Mice
• Mice, Inbred C57BL