[Impact of sera from children with active Henoch-Schönlein purpura on human umbilical venous endothelial cells (HUVECs) and protective effects of methylprednisolone against HUVECs injury].

Abstract

To observe the changes of human umbilical venous endothelial cells (HUVECs) induced by the sera from children with active Henoch-Sch-nlein purpura (HSP) and the protective effects of methylprednisolone against HUVECs injury.
HUVECs were divided into four groups based on the culture conditions: blank control group, normal serum group, HSP serum group, and HSP serum plus methylprednisolone group. The levels of tumor necrosis factor (TNF)-α and interleukin (IL)-8 in the supernatants of each group were detected using ELISA and the nitric oxide (NO) level by nitrate reductase determination. Moreover, the expressions of nuclear factor-kappa B (NF-κB) and Fractalkine in HUVECs were examined by semiquantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot, respectively.
The levels of IL-8, TNF-α, and NO in the HSP serum group were significantly higher than those in the blank control and normal serum groups (P<0.05). Compared with the HSP serum group, the levels of IL-8, TNF-α, and NO in the HSP serum plus methylprednisolone group decreased significantly (P<0.05). The mRNA expression levels of NF-κB and Fractalkine in the HSP serum group were significantly higher than those in the blank control group (P<0.05). The protein expression levels of NF-κB and Fractalkine in the HSP serum group were significantly higher than those in the blank control and normal control group (P<0.05). Compared with the HSP serum group, the mRNA and protein expression levels of NF-κB and Fractalkine in the HSP serum plus methylprednisolone group decreased significantly (P<0.05).
The sera from children with active HSP can induce the in vitro cultured HUVECs to become activated and excrete cytokines. Methylprednisolone may inhibit NF-κB expression, reduce the production of inflammatory factors, and thus alleviate vascular inflamation.