Department of Respiratory Diseases, Clinical School of Nanjing University, Nanjing General Hospital of Nanjing Military Command, Nanjing, Jiangsu 210002, China.
Chin Med J (Engl). 2009 Oct 20;122(20):2466-71.
Antithrombin-III (AT-III), the major inhibitor of thrombin in plasma, also has anti-inflammation property and might have positive effect on sepsis. The present study aimed to investigate the effects of AT-III on inflammatory reaction and pulmonary protection in endotoxin-induced acute lung injury (ALI) rat.
Sixty male Sprague-Dawley rats were randomly assigned equally to normal control group, ALI group, AT-III treatment group, AT-III + heparin treatment group, and heparin treatment group. The pulmonary vascular permeability index (PVPI) was measured by single nuclide tracer technique. The activity of AT-III in plasma was determined by the method of synthetic chromogenic substrata. Tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) levels in serum were determined by enzyme-linked immunosorbent assay. The expressions of lung tissue mitogen-activated protein kinases (ERK1/2, P38 and JNK MAPK) were determined by Western blotting.
Rats had significantly improved lung histopathology in the AT-III treatment group and heparin treatment group compared with the ALI group. The PVPI of the ALI group was 0.38 + or - 0.04, significantly higher than that of the normal control group (0.20 + or - 0.02, P < 0.01), AT-III treatment group (0.30 + or - 0.04, P < 0.01) and heparin treatment group (0.28 + or - 0.04, P < 0.01) respectively. There were no significant differences of PVPI in the ALI group and AT-III + heparin treatment group. The activity of AT-III in plasma in the ALI group was (76 + or - 8)%, significantly lower than that of the normal control group ((96 + or - 11)%, P < 0.05) and AT-III treatment group ((105 + or - 17)%, P < 0.05) respectively. The serum levels of TNF-alpha and IL-6 of the ALI group were (2.770 + or - 0.373) microg/L and (1.615 + or - 0.128) ng/ml respectively, significantly higher than those of the normal control group ((0.506 + or - 0.093) microg/L and (0.233 + or - 0.047) ng/ml respectively, all P < 0.01), AT-III treatment group ((1.774 + or - 0.218) microg/L and (1.140 + or - 0145) ng/ml respectively, all P < 0.01) and heparin treatment group ((1.924 + or - 0.349) microg/L and (1.223 + or - 0.127) ng/ml respectively, all P < 0.01). The lung tissue levels of phospho-ERK1/2 and phospho-P38 MAPK expressions were markedly higher in the ALI group than in the normal control group, AT-III treatment group and heparin treatment group respectively.
AT-III without concomitant heparin inhibited the activation of ERK1/2 and P38 MAPK, down-regulated the levels of downstream cytokines TNF-alpha and IL-6, relieved endothelial permeability, and improved the ALI in endotoxin-induced rats. It might be helpful to administrate AT-III alone, not with concomitant heparin, to those patients with ALI and sepsis.
抗凝血酶-III（AT-III）是血浆中凝血酶的主要抑制剂，它也具有抗炎作用，可能对脓毒症有积极影响。本研究旨在探讨 AT-III 对内毒素诱导的急性肺损伤（ALI）大鼠炎症反应和肺保护的作用。
60 只雄性 Sprague-Dawley 大鼠随机均分为正常对照组、ALI 组、AT-III 治疗组、AT-III+肝素治疗组和肝素治疗组。采用单核素示踪技术测量肺血管通透性指数（PVPI）。采用合成显色基质法测定血浆中 AT-III 的活性。采用酶联免疫吸附法测定血清中肿瘤坏死因子-α（TNF-α）和白细胞介素-6（IL-6）水平。采用 Western blot 法测定肺组织丝裂原活化蛋白激酶（ERK1/2、P38 和 JNK MAPK）的表达。
与 ALI 组相比，AT-III 治疗组和肝素治疗组大鼠的肺组织病理明显改善。ALI 组的 PVPI 为 0.38+0.04，明显高于正常对照组（0.20+0.02，P<0.01）、AT-III 治疗组（0.30+0.04，P<0.01）和肝素治疗组（0.28+0.04，P<0.01）。ALI 组和 AT-III+肝素治疗组的 PVPI 无显著差异。ALI 组血浆 AT-III 活性为（76+8）%，明显低于正常对照组（96+11）%（P<0.05）和 AT-III 治疗组（105+17）%（P<0.05）。ALI 组血清 TNF-α和 IL-6 水平分别为（2.770+0.373）μg/L和（1.615+0.128）ng/ml，明显高于正常对照组（0.506+0.093）μg/L和（0.233+0.047）ng/ml（均 P<0.01）、AT-III 治疗组（1.774+0.218）μg/L和（1.140+0.145）ng/ml（均 P<0.01）和肝素治疗组（1.924+0.349）μg/L和（1.223+0.127）ng/ml（均 P<0.01）。ALI 组肺组织磷酸化 ERK1/2 和磷酸化 P38 MAPK 表达水平明显高于正常对照组、AT-III 治疗组和肝素治疗组。
无肝素的 AT-III 抑制了 ERK1/2 和 P38 MAPK 的激活，下调了下游细胞因子 TNF-α和 IL-6 的水平，减轻了内皮通透性，改善了内毒素诱导的 ALI。对于 ALI 和脓毒症患者，单独给予 AT-III 而不给予肝素可能会有所帮助。
