酸环境对过敏性紫癜患儿血清IgA1诱导血管内皮细胞ASIC1a表达的影响及机制

Effect of low pH on acid-sensing ion channel 1a expression in vascular endothelial cell induced by serum IgA1 from Henoch-Schnlein purpura children and its mechanism

目的初步探讨酸性环境对过敏性紫癜(HSP)患儿血清Ig A1诱导血管内皮细胞酸敏感离子通道1a(ASIC1a)表达的影响及ASIC1a的调控作用。方法体外培养的人皮肤微血管内皮细胞经过处理后,荧光定量PCR检测血管内皮细胞ASIC1a、destrin及α-SM mRNA表达;ELISA测定血管内皮细胞细胞因子;同时采用荧光定量PCR和Western blot检测细胞骨架destrin及α-SM蛋白表达。结果酸化环境中HSP患儿血清Ig A1作用血管内皮细胞后,ASIC1a mRNA表达明显上调(P<0.01);细胞因子IL-8、NO和TM分泌明显增加(P<0.01);ASICs阻滞剂可以显著降低酸化诱导的细胞因子的分泌(P<0.01)。细胞外酸化下,HSP患儿血清Ig A1导致细胞骨架蛋白destrin及α-SM mRNA和蛋白表达明显下调(P<0.01);而ASICs阻断剂组destrin及α-SM mRNA和蛋白表达明显上调(P<0.01)。结论ASIC1a在HSP患儿血管炎的发生中起着重要作用,阻断细胞外ASIC1a能显著改善HSP患儿血管内皮细胞损伤。

Objective To investigate the effect of low p H on acid-sensing ion channel 1 a（ ASIC1 a） expression in vascular endothelial cells induced by serum Ig A1 from Henoch-Schnlein purpura（ HSP） children and regulatory role of ASIC1 a in it. Methods Human dermal microvascular endothelial cells（ HDMECs） treated by serum Ig A1 from children with HSP were incubated in different p H medium. ASIC1 a,destrin and α-SM mRNA expressions in HDMECs were evaluated by real-time quantitative polymerase chain reaction（ q-PCR）. The level of inflammatory cytokines released by vascular endothelial cells was detected by ELISA. Moreover destrin and α-SM protein expression in HDMECs was evaluated by Western blot. Results The results showed that in low p H condition,Ig A1 from HSP children could induce the upregulation of ASIC1 a mRNA expression,stimulate IL-8,NO and TM release of vascular endothelial cells of HSP children. And blockers of ASICs could reduce acid-induced cytokine release of vascular endothelial cells. Moreover destrin and α-SM mRNA and protein expression in HDMECs of HSP children significantly decreased when exposure to extracellular acidosis. However blockers of ASICs increased destrin andα-SM mRNA and protein expression in vascular endothelial cells of HSP children. Conclusions These findings showed that activation of ASIC1 a could be involved in the vascular endothelial cell injury of HSP children. Blocking ASIC1 a may have a significant protective effect on the inflammatory injury of vascular endothelial cells.