Thymol Protects against Aspergillus Fumigatus Keratitis by Inhibiting the LOX-1/IL-1ß Signaling Pathway.

OBJECTIVE: To explore the anti-inflammatory effects and mechanisms of action of thymol in Aspergillus fumigatus (A. fumigatus) keratitis. METHODS: The minimum inhibitory concentration of thymol against A. fumigatus was detected. To characterize the anti-inflammatory effects of thymol, mouse corneas and human corneal epithelial cells were pretreated with thymol or dimethyl sulfoxide (DMSO) before infection with A. fumigatus spores. Slit-lamp microscopy, immunohistochemistry, myeloperoxidase detection, quantitative real-time polymerase chain reaction, and Western blotting were used to assess infection. Neutrophil and macrophage recruitment, in addition to the secretion of LOX-1 and IL-1ß, were quantified to evaluate the relative contribution of thymol to the inflammatory response. RESULTS: We confirmed that the growth of A. fumigatus was directly inhibited by thymol. In contrast with the DMSO group, there was a lower degree of inflammation in the mouse corneas of the thymol-pretreated group. This was characterized by significantly lower clinical scores, less inflammatory cell infiltration, and lower expression of LOX-1 and IL-1ß. Similarly, in vitro experiments indicated that the production of LOX-1 and IL-1ß was significantly inhibited after thymol treatment, in contrast with the DMSO-pretreated group. CONCLUSION: Our findings demonstrate that thymol exerted a direct fungistatic activity on A. fumigatus. Furthermore, thymol played a protective role in fungal keratitis by inhibiting LOX-1/IL-1ß signaling pathway and reducing the recruitment of neutrophils and macrophages.

Oxidative stress induced by carboplatin promotes apoptosis and inhibits migration of HN-3 cells.

Laryngeal squamous cell carcinoma (LSCC) is currently a serious public health problem in China; thus, it is urgent to identify effective treatment strategies for this disease. Previous studies demonstrated that reactive oxygen species (ROS) serve important roles in the apoptosis of LSCC cells. It has also been indicated that carboplatin (CBDCA), a second-generation platinum compound with broad antineoplastic properties, is able to induce oxidative stress to produce ROS, which in turn promotes apoptosis. Thus, the present study investigated if CBDCA is cytotoxic in LSCC cells due to the oxidative stress caused by ROS. Therefore, an MTT assay was performed to determine the cell viability of HN-3 LSCC cells following treatment with different doses of CBDCA. Subsequently, the expression levels of ROS and the rate of apoptosis/necrosis were evaluated in the cells. Following this, the HN-3 cells were co-treated with CBDCA and glutathione (GSH) or H2O2, followed by an MTT assay, a cell migration assay and western blot analysis. The results demonstrated that CBDCA reduced the viability of HN-3 cells in a time- and dose-dependent manner and promoted the production of ROS and apoptosis at certain doses. Additionally, the combination treatment of CBDCA and H2O2 enhanced the inhibitory effects of CBDCA on cell viability and migration ability, and promoted apoptosis in HN-3 cells; whereas the combined treatment of CBDCA and GSH exerted opposite effects. The results of the present study demonstrated that CBDCA promotes the apoptosis of HN-3 cells through accumulation of ROS, which may provide a novel treatment strategy for treating LSCC.

Sulforaphene Enhances The Efficacy of Photodynamic Therapy In Anaplastic Thyroid Cancer Through Ras/RAF/MEK/ERK Pathway Suppression.

Sulforaphene (SFE), a natural isothiocyanate from cruciferous vegetables has shown a potential anticancer effect against cervical and lung cancer. Palliative treatments like photodynamic therapy (PDT) are being implemented for a long time however, the results are still not promising in case of aggressive cancers like anaplastic thyroid cancer. The objective of this work is to establish an alternative method with the combination of photofrin-PDT and sulforaphene, a natural isothiocyanate from cruciferous vegetables, against human anaplastic thyroid cancer to enhance the efficacy of PDT. In this study, cell viability of FRO cells due to combination treatment was analyzed by MTT assay, Cell cycle arrest, MMP depolarization and ROS generation, analyzed by flow cytometry. Western blot analysis of various proliferative proteins was performed to assess the activity of combination treatment against FRO cells. From the results, sulforaphene alone showed no cytotoxicity against normal cells, however, combination of sulforaphene and photofrin mediated PDT showed a noticeable decrease in cell proliferation against FRO cells. Combination treatment synergistically caused cell cycle arrest via ROS generation and MMP depolarization. The expressions of Ras, MEK, ERK, B-Raf proteins significantly modulated due to combination treatment. PDT and SFE can induce apoptosis in anaplastic thyroid cancer cells individually but while treated in combination, it enhanced the apoptotic and anti-proliferative effect, much higher than the individual doses. In summary, our work designates sulforaphene as a unique natural enhancer of efficacy with PDT against anaplastic thyroid cancer.