ABSTRACT
PURPOSE: Aspergillus fumigatus (A. fumigatus) keratitis is a type of infectious corneal disease that significantly impairs vision. The objective of this study is to evaluate the therapeutic potential of chelerythrine (CHE) on A. fumigatus keratitis. METHODS: The antifungal activity of CHE was assessed through various tests including the minimum inhibitory concentration test, scanning electron microscopy, transmission electron microscopy, propidium iodide uptake test and plate count. Neutrophil infiltration and activity were assessed using immunofluorescence staining and the myeloperoxidase test. RT-PCR, western blotting assay, and ELISA were performed to measure the expression levels of proinflammatory cytokines (IL-1ß and IL-6), NF-E2-related factor (Nrf2), heme oxygenase-1 (HO-1), and lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), as well as to determine the ratio of phosphorylated-p38 (p-p38) mitogen-activated protein kinase (MAPK) to p38 MAPK. RESULTS: In vitro, CHE inhibited the growth of A. fumigatus conidia, reduced fungal hyphae survival, and prevented fungal biofilm formation. In vivo, CHE reduced the severity of A. fumigatus keratitis and exhibited an excellent anti-inflammatory effect by blocking neutrophil infiltration. Furthermore, CHE decreased the expression levels of proinflammatory cytokines and LOX-1 at both mRNA and protein levels, while also decreasing the p-p38 MAPK/p38 MAPK ratio. Additionally, CHE increased the expression levels of Nrf2 and HO-1. CONCLUSION: CHE provides protection against A. fumigatus keratitis through multiple mechanisms, including reducing fungal survival, inducing anti-inflammatory effects, enhancing Nrf2 and HO-1 expression, and suppressing the signaling pathway of LOX-1/p38 MAPK.
ABSTRACT
PURPOSE: To determine the antifungal, anti-inflammatory and neuroprotective effects of resveratrol (RES) in Aspergillus fumigatus (A. fumigatus) keratitis. METHODS: Cytotoxicity assay and Draize eye assay were performed to assess the toxicity of RES. The antifungal effect of RES was assessed by minimal inhibitory concentration, scanning or transmission electron microscopy, propidium iodide uptake assay, and Calcofluor white staining. Phosphorylation of p38 MAPK, mRNA and protein levels of Dectin-1 and related inflammatory factors were measured by qRT-PCR, ELISA and Western blot in vitro and in vivo. Clinical score, HE staining, plate count, and myeloperoxidase test were used to observe the progress of fungal keratitis. IF staining, qRT-PCR, and the Von Frey test were selected to assess the neuroprotective effects of RES. RESULTS: RES suppressed A. fumigatus hyphae growth and altered hyphae morphology in vitro. RES decreased the expression of Dectin-1, IL-1ß and TNF-α, as well as p38 MAPK phosphorylation expression, and also decreased clinical scores, reduced inflammatory cell infiltration and neutrophil activity, and decreased fungal load. RES also protected corneal basal nerve fibers, down-regulated mechanosensitivity thresholds, and increased the mRNA levels of CGRP and TRPV-1.. CONCLUSION: These evidences revealed that RES could exert antifungal effects on A. fumigatus and ameliorate FK through suppressing the Dectin-1/p38 MAPK pathway to down-regulate IL-1ß, IL-6, etc. expression and play protective effect on corneal nerves.
Subject(s)
Anti-Inflammatory Agents , Aspergillus fumigatus , Keratitis , Lectins, C-Type , Neuroprotective Agents , Resveratrol , p38 Mitogen-Activated Protein Kinases , Aspergillus fumigatus/drug effects , Lectins, C-Type/metabolism , Keratitis/drug therapy , Keratitis/metabolism , Keratitis/microbiology , Resveratrol/pharmacology , p38 Mitogen-Activated Protein Kinases/metabolism , Animals , Neuroprotective Agents/pharmacology , Anti-Inflammatory Agents/pharmacology , Mice , Aspergillosis/drug therapy , Aspergillosis/metabolism , Antifungal Agents/pharmacology , Male , Signal Transduction/drug effects , MAP Kinase Signaling System/drug effects , Cornea/drug effects , Cornea/metabolismABSTRACT
Aspergillus fumigatus keratitis is a potential blinding disease associated with A. fumigatus invasion and excessive inflammatory response. Benzyl isothiocyanate (BITC) is a secondary metabolite with broad antibacterial and anti-inflammatory activity extracted from cruciferous species. However, the role of BITC in A. fumigatus keratitis has not been discovered yet. This study aims to explore the antifungal and anti-inflammatory effects and mechanisms of BITC in A. fumigatus keratitis. Our results provided evidences that BITC exerted antifungal effects against A. fumigatus by damaging cell membranes, mitochondria, adhesion, and biofilms in a concentration-dependent manner. In vivo, fungal load and inflammatory response including inflammatory cell infiltration and pro-inflammatory cytokine expression were reduced in BITC-treated A. fumigatus keratitis. Additionally, BITC significantly decreased Mincle, IL-1ß, TNF-α, and IL-6 expression in RAW264.7 cells that stimulated by A. fumigatus or Mincle ligand trehalose-6,6-dibehenate. In summary, BITC possessed fungicidal activities and could improve the prognosis of A. fumigatus keratitis by reducing fungal load and inhibiting the inflammatory response mediated by Mincle.
ABSTRACT
Fungal keratitis (FK) is a blinding ocular disease, which mainly results from fungal damage and excessive inflammation. Pentoxifylline, a kind of methylxanthine, has been discovered to have anti-inflammatory properties in various infectious diseases, hinting a potential therapeutic effect on treating corneal fungal infection. Whereas, the therapeutic impact of pentoxifylline on fungal keratitis is still uncertain. This study investigated the antifungal capability against Aspergillus fumigatus and the anti-inflammatory role of pentoxifylline by activating nuclear factor, erythroid 2 like 2 (Nrf2)/heme oxygenase1 (HO1) pathway in the process of FK. In our research, we demonstrated that pentoxifylline could effectively inhibit fungal growth and inflammatory reaction. Pentoxifylline reduced the production of pro-inflammatory factors by stimulating the Nrf2/HO1 pathway. Although there was no statistical difference between the curative efficacy of pentoxifylline and natamycin application to FK, pentoxifylline could promote corneal epithelial repair and was less toxicity to the ocular surface than natamycin. In conclusion, pentoxifylline performs antifungal and anti-inflammatory effects by lessening the fungus burden and activating the Nrf2/HO1 pathway, hinting that it has the potential to be a new therapeutic medication for Aspergillus fumigatus keratitis.
Subject(s)
Aspergillosis , Eye Infections, Fungal , Keratitis , Pentoxifylline , Humans , Animals , Mice , Aspergillus fumigatus , Natamycin/therapeutic use , Pentoxifylline/pharmacology , Pentoxifylline/therapeutic use , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , NF-E2-Related Factor 2 , Aspergillosis/drug therapy , Aspergillosis/metabolism , Keratitis/metabolism , Inflammation/drug therapy , Eye Infections, Fungal/drug therapy , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Mice, Inbred C57BLABSTRACT
Fungal keratitis is an infectious vision-threatening disease that has a poor prognosis, and the clinical therapeutic drugs have multiple limitations, such as epithelial toxicity and low bioavailability. Therefore, new antifungal treatment strategies must be developed. 4-Methoxycinnamic acid (MCA) is a widely occurring natural phenolic acid that has been proven to have multiple effects, such as antibacterial, antifungal, anti-inflammatory, neuroprotective, and inhibiting cancer. In this research, we explored the effects and underlying mechanisms of MCA on A. fumigatus keratitis and the antifungal effects of the combination of MCA and natamycin (NATA) on A. fumigatus. We found that MCA exerts antifungal effects by inhibiting the synthesis of the fungal cell wall, changing the permeability of fungal cell membranes. Moreover, the MCA-NATA combination exhibited synergy for A. fumigatus. In addition, MCA exerted an anti-inflammatory effect by downregulating the inflammatory factors (IL-1ß, TNF-α, IL-6, and iNOS) in C57BL/6 mice and RAW264.7 cells. The anti-inflammatory mechanism of MCA was associated with the Mincle signal pathway. In summary, MCA acts as a potential therapeutic drug for fungal keratitis and a potential antifungal sensitizer for natamycin. MCA inhibits fungal cell wall synthesis, destroys the permeability of fungal cell membranes, and mediates the anti-inflammatory, immune response of the host.
Subject(s)
Aspergillosis , Eye Infections, Fungal , Keratitis , Animals , Mice , Natamycin/pharmacology , Natamycin/therapeutic use , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Aspergillus fumigatus , Mice, Inbred C57BL , Eye Infections, Fungal/drug therapyABSTRACT
OBJECTIVE: To discover the anatomical basis of retroperitoneal laparoscopic surgery. METHODS: Twenty Chinese adult cadavers including 12 and 8 woman were anatomized. The relationship between nerves, vessels of the lateral abdominal wall, retroperitoneal structures and the path of retroperitoneal laparoscopic surgery were measured. RESULTS: In male cadavers, the distance between the iliac crest and lumbar trigonum was 4.02 +/- 1.26 cm on the left, and 3.83 +/- 0.90 cm an the right. The distance between the iliac crest and ilio-hypogastric nerve was 0.82 +/- 0.13 cm on the left and 0.84 +/- 0.08 cm on the right. The distance between the subcostal nerve and XII rib in the posterior axillary line and midaxilla line was 0.79 +/- 0.26 cm, 1.65 +/- 1.12 cm on the left and 0.78 +/- 0.30 cm, 1.59 +/- 1.07 cm on the right respectively. The distance between the ureter of inferior pole of kidney and extra-border of psoas was 2.24 +/- 0.67 cm on the left and 2.19 +/- 0.73 cm on the right. The distance between crossing of the ureter and iliac vessels and extra-border of psoas was 3.91 +/- 0.59 cm on the left and 3.76 +/- 0.53 cm on the right. In female cadavers, the distance between the iliac crest and trigonum lumbale was 3.90 +/- 0.37 cm on the left and 3.87 +/- 0.37 cm on the right. The distance between the iliac crest and ilio-hypogastric nerve was 0.94 +/- 0.06 cm on the left and 0.93 +/- 0.10 cm on the right. The distance between the subcostal nerve and XII rib in the posterior axillary line and midaxilla line was 0.61 +/- 0.14 cm and 1.37 +/- 0.89 cm on the left and 0.64 +/- 0.13 cm, 1.32 +/- 0.95 cm on the right respectively. The distance between the ureter of inferior pole of kidney and extra-border of psoas was 2.00 +/- 0.23 cm on the left and 1.91 +/- 0.13 cm on the right. The distance between crossing of the ureter and iliac vessels and extra-border of psoas was 3.43 +/- 0.31 cm on the left and 3.85 +/- 0.43 cm on the right. CONCLUSIONS: The top of the lumbar trigonum which is 2 cm above the iliac crest selected as the first point and 2 cm inferior to the XII rib in the posterior axillary line selected as the second point is the anatomical basis for retroperitoneal laparoscopic surgery. It can reduce the opportunity to injury nerves, vessels and retroperitoneal structures while making retroperitoneal laparoscopic surgery easy.