内皮祖细胞对急性损伤肺组织的抗炎作用

Anti-inflammatory effect of endothelial progenitor cell transplantation in rats with acute lung injury

目的观察内皮祖细胞移植对急性损伤肺组织的抗炎作用。方法清洁级同遗传背景SD大鼠36只,按随机数字表法分为PBS组、LPS组、内皮祖细胞(endothelial progenitor cells,EPC)组(n=12)。采用密度梯度离心法分离、培养EPCs。LPS组、EPC组大鼠经尾静脉注射脂多糖建立急性肺损伤模型;PBS组仅给予等量的PBS溶液。造模30 min后,PBS组、EPC组大鼠经尾静脉注入EPCs悬液;LPS组大鼠同法注入等量的PBS溶液。7 d后取动物血清及肺组织,分别检测各组肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞介素-1β(interleukin-1β,IL-1β)、中性粒细胞弹性蛋白酶(neutrophil elastase,NE)及髓过氧化物酶(myeloperoxidase,MPO)的表达。结果与PBS组比较,LPS组中SD大鼠的肺损伤评分、肺组织W/D比值增加(P<0.01,P<0.05),血清中TNF-α、IL-1β的含量增加[(195.88±10.08)vs(39.40±2.11)pg/m L,(143.33±10.19)vs(49.18±2.52)pg/m L,P<0.05],肺组织NE、MPO的含量也较PBS组增加[(3.88±0.02)vs(0.65±0.03)ng/m L,(7.11±0.41)vs(1.32±0.09)U/g,P<0.05];而EPC组中SD大鼠的肺损伤评分、肺组织W/D比值较LPS组降低(P<0.05),血清中TNF-α、IL-1β的含量较LPS组减少[(103.52±10.07)vs(195.88±10.08)pg/m L,(78.04±3.98)vs(143.33±10.19)pg/m L,P<0.05],肺组织NE、MPO的含量也较LPS组降低[(1.98±0.05)vs(3.88±0.02)ng/m L,(4.63±0.37)vs(7.11±0.41)U/g,P<0.05]。结论内皮祖细胞移植后能抑制炎症介质的表达,缓解肺损伤。

Objective To investigate the anti-inflammatory effect of transplantation of endothelial progenitor cells （EPCs） in rats with acute lung injury. Methods Thirty-six clean Sprague Dawley rats with the same genetic background were randomly divided into 3 groups （n=12）： phosphate buffer solution （PBS） group, lipopolysaccharide （LPS） group, and EPCs group. The EPCs were isolated and cultured with density gradient centrifugation. The rats in the LPS and EPC groups were intravenously injected with 5 mg/kg LPS to induce lung injury. The rats in the PBS group were treated with only PBS at the same dose. Half an hour later, the rats in the EPC and PBS groups were injected with bone marrow-derived EPCs （2.0×106/0.5 mL） through the tail vein, and the rats in the LPS group were treated with the same dose of PBS. The amount of tumor necrosis factor-α （TNF-α）, interleukin-1β （IL-1β）, neutrophil elastase （NE） and myeloperoxidase （MPO） in the 3 groups were detected on the 7th day after EPCs transplantation. Results Compared with the PBS group, the lung injury score and the lung wet-to-dry ratio were increased in the LPS group, and the amount of TNF-α （195.88±10.08 vs 39.40±2.11 pg/mL）, IL-1β （143.33±10.19 vs 49.18±2.52 pg/mL）, NE （3.88±0.02 vs 0.65±0.03 ng/mL）, and MPO （7.11±0.41 vs 1.32±0.09 U/g） were significantly increased （all P〈0.05）. Compared with the LPS group, the lung injury score and lung wet-to-dry ratio were decreased in the EPC group, and the amount of TNF-α （103.52±10.07 vs 195.88±10.08 pg/mL）, IL-1β （78.04±3.98 vs 143.33±10.19 pg/mL）, NE （1.98±0.05 vs 3.88±0.02 ng/mL）, and MPO （4.63±0.37 vs 7.11±0.41 U/g） were significantly reduced （P〈0.05）. Conclusion Transplantation of EPCs can reduce the inflammatory mediators and improve the injured lung tissues in rats with acute lung injury.