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Wedelolactone, a chemical compound extracted from Wedelia calendulacea or Eclipta alba , has been reported to regulate key steps in inflammation. However, the effects of wedelolactone on fungal keratitis are not known. Hence, we aimed to characterize the impact of wedelolactone in Aspergillus fumigatus keratitis. Aspergillus fumigatus was used to establish an in vivo mouse model of fungal keratitis and an in vitro model of THP-1 macrophages. Mice and THP-1 macrophages were pre-treated with wedelolactone. Clinical evaluation, myeloperoxidase (MPO) assay, neutrophil staining, western blot and quantitative polymerase chain reaction (qRT-PCR) were used to assess the effect of wedelolactone on A. fumigatus infection. Therapeutic effect of natamycin treatment with or without wedelolactone was measured via slit lamp microscopy. We confirmed that wedelolactone attenuated the infiltration of neutrophils and decreased MPO level at earlier time points in mice with A. fumigatus keratitis. Pre-treatment with wedelolactone decreased pro-inflammatory cytokine interleukin 1 beta (IL-1β) maturation by inhibiting caspase-1 activity. Combined with natamycin, wedelolactone protected corneal transparency in mouse with fungal keratitis. Present findings indicated that wedelolactone reduced host immune responses by attenuating neutrophil recruitment and IL-1β maturation in Aspergillus fumigatus keratitis. Wedelolactone combined with an antifungal medicine could be a potential therapy for reducing lesion severity in fungal keratitis. • Wedelolactone played a protective role to cornea in mouse early fungal keratitis (FK). • Wedelolactone impaired IL-1β maturation against A. fumigatus infection by caspase-1. • Wedelolactone combined with an antifungal medicine may be a potential therapy to FK. [ABSTRACT FROM AUTHOR]

Abstract Purpose Maresin1, a lipid mediator derived from polyunsaturated fatty acids, has been shown to suppress the inflammatory response in various inflammatory diseases. However, its effects in fungal keratitis are still uncertain. In this study, we investigated the role of maresin1 (MaR1) in Aspergillus fumigatus keratitis of the eye in a mouse model. Methods Mouse corneas were infected with A. fumigatus by corneal intrastromal injection. Two hours after infection, maresin1 (5 ng/5 μl) was delivered by subconjunctival injection. Then, topical administration of maresin1 (5 ng/3 μl) was applied to mouse corneas twice a day from day 1 to day 5. The development of FK lesions, the production of chemokines, the production of inflammation cytokines and the levels of p-GSK3β were measured via slit-lamp biomicroscope, quantitative polymerase chain reaction (qRT-PCR) and western blot. The presence of neutrophils in the cornea was detected by immunofluorescence staining and myeloperoxidase. The effect of maresin1 on A. fumigatus stimulated mouse macrophage RAW264.7 cells was assessed via PCR and Western blot. Results In our study, administration of maresin1 reduced the severity of fungal keratitis with infiltration of fewer neutrophils and reduced levels of the chemokine CXCL1, while the anti-inflammatory cytokines such as IL-10 were enhanced compared with the PBS group. Additionally, in vitro studies showed that treatment with maresin1 inhibited the production of the chemokine CXCL1 and enhanced IL-10 levels in A. fumigatus stimulated RAW264.7 mouse macrophages. Moreover, levels of p-GSK3β increased after maresin1 treatment in A. fumigatus stimulated RAW264.7 cells. Conclusion Taken together, these findings demonstrate that treatment with maresin1 moderates corneal inflammation through reducing neutrophil recruitment and levels of the chemokine CXCL1 and enhancing the anti-inflammatory cytokine IL-10 in A. fumigatus keratitis. Additionally, maresin1 alters levels of GSK3β phosphorylation to regulate CXCL1 and IL-10 expression in response to A. fumigatus infection. Topical administration of maresin1 may emerge as a novel anti-inflammatory molecule and has a protective role in A. fumigatus keratitis. Highlights • Maresin1 alleviates corneal lesions caused by Aspergillus fumigatus in C57BL/6 mouse. • Maresin1 increases p-GSK3β levels to regulate CXCL1 and IL-10 expression in response to Aspergillus fumigatus infection. • Maresin1 inhibits neutrophil recruitment into corneal stroma in mouse Aspergillus fumigatus keratitis. [ABSTRACT FROM AUTHOR]

• Nerolidol protected the corneas from infection by inhibiting the growth of Aspergillus fumigatus. • Nerolidol played a protective role to corneal transparency in mouse A. fumigatus keratitis. • Nerolidol impaired LOX-1/IL-1β signaling in mice corneas and HCECs infected by A. fumigatus. Nerolidol, a naturally occurring sesquiterpene has both anti-microbial and anti-inflammatory properties. The current study aims to investigate the antifungal and the anti-inflammatory effects of nerolidol against mouse Aspergillus fumigatus (A. fumigatus) keratitis. The minimum inhibitory concentration (MIC) and cytotoxicity tests were used to study the antifungal ability. For in vivo and in vitro studies, the mouse corneas and the human corneal epithelial cells (HCECs) infected with A. fumigatus spores were intervented with nerolidol or phosphate buffer saline (PBS). Thereafter, the effect of the nerolidol on the response against inflammation was analyzed using the following parameters: recruitment of the neutrophils or macrophages and the expression of the lectin-type oxidized low density lipoprotein receptor-1 (LOX-1) and interleukin 1β (IL-1β). Techniques used were the slit lamp, immunofluorescence, myeloperoxidase (MPO) detection, quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. Nerolidol directly inhibits the growth of A. fumigatus. The administration of nerolidol reduced the severity of fungal keratitis with infiltration of fewer inflammatory cells and reduced levels of the LOX-1, as well the anti-inflammatory cytokines such as IL-1β were reduced compared with the PBS group. Additionally, in vitro studies showed that treatment with nerolidol inhibited the production of the LOX-1 / IL-1β levels in A. fumigatus stimulated HCECs. Nerolidol attenuated the A. fumigatus keratitis inflammatory response by inhibiting the growth of A. fumigatus , reducing the recruitment of the neutrophils and the macrophages, and inhibiting the LOX-1/ IL-1β signaling. [ABSTRACT FROM AUTHOR]