Effects of emodin on expression of cytokines induced by lipopolysaccharide in corneal fibroblasts / 中国医学科学院学报

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the effects of emodin on expression of cytokines induced by lipopolysaccharide (LPS) in cultured human corneal fibroblasts in vitro.</p><p><b>METHODS</b>Primary human corneal fibroblasts of passages 4 were used in this research. Cells were treated with 10 microg/L LPS for 1, 2, 4, or 8 hours, which were pretreated with or without emodin for 30 minutes before LPS challenge. The degeneration of inhibitor of kappaB-alpha (I kappaB-alpha) and the effect of emodin on it were analyzed by Western blot analysis with a specific antibody. The cellular abundance of the mRNA of interleukin (IL)-6 and IL-8 from corneal fibroblasts under different conditions was determined by reverse transcriptase polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>Compared with cells without LPS treatment, I kappaB-alpha level significantly decreased in every time point after LPS challenge (P < 0.01). Emodin inhibited the LPS-induced degeneration of I kappaB-alpha by corneal fibroblasts in a dose-dependent manner (P < 0.05). Compared with cells without LPS treatment, the expressions of IL-6 and IL-8 mRNA significantly increased in every time point after LPS challenge (P < 0.01). At the same time, the expressions of the mRNA of IL-6 and IL-8 induced by LPS in corneal fibroblasts were also inhibited by emodin in a dose-dependent manner (P < 0.05).</p><p><b>CONCLUSION</b>Emodin can inhibit the expressions of IL-6 and IL-8 mRNA induced by LPS in corneal fibroblasts, which maybe via inhibiting the degeneration of I kappaB-alpha and suppressing the activation of nuclear factor-kappaB.</p>