Objective To detect the effects of cytokines on the expression of early growth response gene-1 (Egr-1) in cultured human retinal pigment epithelial (RPE) cells. Methods Immunofluorescence staining, Western blotting and reverse transcription polymerase chain reaction (RT-PCR) were used to detect and quantitatively analyze the expression of Egr-1 protein and mRNA in cultured human RPE cells which were exposed to stimulants, including 20 mu;g/ml lipopolysaccharide (LPS), 40 ng/ml tumor necrosis factor (TNF)-alpha;, 10 U/ml interferon (IFN)gamma;, 30% supernatant of monocyte/macrophage strain (THP1 cells) and the vitreous humor from healthy human eyeballs, for 0, 10, 20, 30, 40 and 60 minutes, respectively. Results The RPE cells stimulated for 0 minute revealed faint green fluorescence of Egr-1 in the cytoplasm. With exposure to the stimulants, the expressionof Egr-1 increased obviously and b green fluorescence was found in cytoplasm in some nuclei of RPE cells. Compared with the untreated RPE cells, after stimulated by 20 mu;g/ml LPS, 40 ng/ml TNFalpha;, 10 U/ml IFNgamma;, 30% supernatant of THP-1 cells and the vitreous humor, the approximate ultimate amplitudes of Egr-1 mRNA enhanced 1.9, 1.3, 14, 1.2, and 1.4 times, respectively; the greatest amplitudes of Egr-1 protein increased 3.4, 1.2, 1.7, 32, and 1.3 times, respectively. Conclusion LPS, TNF-alpha;, IFN-gamma;, supernatant of THP-1 cells and the vitreous humor can upregulate the expression of Egr-1 mRNA and protein in cultured human RPE cells, and induce its nuclear transposition, which suggests the activation of Egr-1.
ObjectiveTo investigate the effects of interleukin (IL)-26 on the late phase of lipopolysaccharides (LPS)-induced lung inflammation in mouse model.MethodsThirty-two mice were equally and randomly divided into four groups: blank control group, IL-26 control group, LPS model group, and IL-26 intervention group. The blank control group was given intranasal administration of phosphate buffered solution (PBS, 40 μl) and PBS (40 μl) 10 minutes apart. The IL-26 control group was given recombinant human interleukin-26 (rhIL-26; 50 μg/kg, dissolved in 40 μg PBS) and PBS successively. The LPS model group was given intranasal administration of PBS (40 μl) and LPS (10 mg/kg, dissolved in 40 μl PBS) at 10 minutes interval. The IL-26 intervention group was given intranasal administration of rhIL-26 and LPS at 10 minutes interval. Seventy-two hours later after treatment, bronchoalveolar lavage fluid (BALF) cell count, cytokine assay and pathological staining of lung tissue were performed in each group. The gene expression of inflammatory pathway in lung tissue was detected by RT-PCR. One-way ANOVA was used for comparison between groups. ResultsCompared with the blank control group, the expression of tumor necrosis factor-α and activating transcription factor 3 in IL-26 control group increased significantly (all P < 0.05). The number of peripheral blood mononuclear cells, total BALF cells, lymphocytes and neutrophils, and the content of macrophage inflammatory protein-1a in BALF were significantly increased in IL-26 intervention group comparing with LPS model group (all P < 0.05). IL-26 intervention group had more inflammatory subsidence in interstitial, perivascular, peribronchial and mean values than LPS model group (all P < 0.05). The expressions of Toll-like receptor 4, Toll-like receptor 2 and interferon γ induced protein 10 in IL-26 intervention group were significantly higher than those in LPS model group (all P < 0.05).ConclusionIL-26 can significantly alleviate the late inflammatory reaction of lung tissue in LPS-induced mouse inflammation model.