评价萝卜硫素对脓毒症急性肺损伤大鼠氧化应激损伤及脱嘌呤/脱嘧啶核酸内切酶1（APE1）表达的影响。

按随机数字表法将60只Sprague-Dawley大鼠分成三组：假手术组、模型组和治疗组，每组各20只。假手术组仅进行剖腹和关腹操作，模型组和治疗组采用盲肠结扎穿孔术（CLP）制备大鼠脓毒症模型，治疗组大鼠在术后立即通过腹腔内注射给予50 mg/kg的萝卜硫素注射液，其余两组注入等量等渗NaCl溶液。于术后24 h右侧颈总动脉采集动脉血标本，然后处死大鼠取肺组织。光镜下观察病理学结果，测定肺组织湿/干比。同时，采用酶联免疫吸附试验（ELISA）检测肺组织匀浆标本谷胱甘肽（GSH）和超氧化物歧化酶（SOD）表达情况，采用蛋白质印迹法检测肺组织APE1的表达。

苏木素-伊红（HE）染色结果显示，假手术组肺组织结构清晰，未见明显水肿以及炎症细胞浸润；与假手术组相比，模型组大鼠肺组织病理形态学损伤严重，而治疗组肺组织损伤较模型组有所减轻。三组大鼠肺组织湿/干比（3.49 ± 0.26、5.56 ± 0.20、4.96 ± 0.15）、动脉氧合指数（453 ± 23、232 ± 22、332 ± 11）、GSH[（8.57 ± 0.26）、（4.36 ± 0.08）、（6.23 ± 0.20）mg/g]及SOD表达水平[（91.0 ± 3.0）、（55.5 ± 2.5）、（72.1 ± 2.4）NU/mg]比较差异均有统计学意义（F = 107.897、128.676、275.863、183.797，P均< 0.001）。进一步两两比较发现，模型组、治疗组大鼠肺组织湿/干比较假手术组均显著上升（P均< 0.05），治疗组肺组织湿/干比较模型组下降（P < 0.05）；而模型组、治疗组动脉氧合指数及氧化损伤指标GSH和SOD水平较假手术组均显著下降（P均< 0.05），且治疗组较模型组均上升（P均< 0.05）。蛋白质印迹法结果显示三组大鼠肺组织APE1表达水平比较差异有统计学意义（F = 453.991，P < 0.001），进一步两两比较发现模型组、治疗组大鼠肺组织APE1表达较假手术组均显著下降（P均< 0.05），但治疗组较模型组明显上升（P < 0.05）。

萝卜硫素可减轻脓毒症大鼠急性肺损伤，其机制可能与改善肺组织氧化应激反应及上调APE1表达有关。

To evaluate the effects of sulforaphane on oxidative stress injury and apurinic/apyrimidinic endonuclease 1 (APE1) expression in rats with acute lung injury induced by sepsis.

Sixty Sprague-Dawley rats were divided into three groups according to the random number table: the sham operation group, the model group and the treatment group with 20 rats in each group. In the sham operation group, only laparotomy and abdominal operation were performed, while rat sepsis models were prepared by cecal ligation and puncture (CLP) in the model and the treatment groups. Rats in the treatment group were given intraperitoneal injection of 50 mg/kg sulforaphane immediately after operation, and the remaining two groups were injected with equal normal saline. The arterial blood samples were collected from the right common carotid artery at 24 h after operation; then the lung tissues were taken out after the rats were sacrificed. The pathological results were observed under light microscope and the wet/dry ratio of lung tissues was measured. Meanwhile, the expressions of superoxide dismutase (SOD) and glutathione (GSH) in lung homogenates were detected by enzyme-linked immunosorbent assay (ELISA), and the expression of APE1 in lung tissues was examined by Western-blotting.

Hematoxylin-eosin (HE) staining showed that the lung tissues of the sham operation group were structurally clear with no obvious edema and inflammatory cell infiltration, the pathological changes in the model group were serious, and the lung injury was less in the treatment group than in the model group. There were significant differences in the wet/dry ratio (3.49 ± 0.26, 5.56 ± 0.20, 4.96 ± 0.15), arterial oxygenation index (453 ± 23, 232 ± 22, 332 ± 11), GSH expression [(8.57 ± 0.26), (4.36 ± 0.08), (6.23 ± 0.20) mg/g] and SOD expression [(91.0 ± 3.0), (55.5 ± 2.5), (72.1 ± 2.4) NU/mg] among the three groups (F = 107.897, 128.676, 275.863, 183.797; all P < 0.001). The wet/dry ratio was significantly higher in the model and the treatment groups than in the sham operation group (all P < 0.05), while it was significantly lower in the treatment group than in the model group (P < 0.05). Compared with the sham operation group, the oxygenation index, GSH and SOD decreased significantly in the other two groups (all P < 0.05), while these factors were significantly higher in the treatment group than in the model group (all P < 0.05). Western-blotting showed that the expression of APE1 in lung tissues changed significantly in all three groups (F = 453.991, P < 0.001). It decreased more significantly in the model and treatment groups than in the sham operation group (all P < 0.05), while it was significantly higher in the treatment group than in the model group (P < 0.05).

Sulforaphane can alleviate acute lung injury in septic rats, and its mechanism may be related to the improvement of oxidative stress response and up regulation of APE1 expression in lung tissues.