血必净对爆炸致家兔急性肺损伤的保护作用及其机制研究

Protective effect of Xuebijing on blast-induced acute lung injury in rabbits and its mechanism

目的探讨血必净对爆炸致家兔急性肺损伤(ALI)时肺组织核转录因子-κB(NF-κB)活性的影响及其对ALI的作用机制。方法将32只清洁家兔随机分为4组,每组8只。对照组(NS)、ALI组、低剂量血必净干预组(L-XBJ)和高剂量血必净干预组(H-XBJ)。爆炸致伤家兔,复制ALI动物模型后,L-XBJ、H-XBJ组分别注射10和20 ml/kg血必净溶液,NS、ALI两组注射等量生理盐水。24 h时采集静脉血及部分肺组织,测定肺湿干重比(W/D),酶联免疫吸附法检测血清中肿瘤坏死因子-α(TNF-α)、白细胞介素6(IL-6)、白细胞介素10(IL-10)水平,Western blot检测肺组织NF-κB蛋白表达量,逆转录聚合酶链反应检测肺组织NF-κB m RNA表达水平,光镜下观察肺组织病理学改变。结果 L-XBJ、H-XBJ组W/D小于ALI组并呈浓度依赖性。与ALI组比较,血必净可以降低血清中TNF-α、IL-6含量,降低NF-κB m RNA和蛋白表达,提高IL-10含量。肺病理切片显示,ALI组肺组织严重出血、水肿及大量炎症细胞浸润,L-XBJ、H-XBJ组肺损伤程度明显减轻。结论血必净干预能显著下调促炎因子TNF-α、IL-6水平及上调抗炎因子IL-10水平,并抑制NF-κB活化,阻断其介导的炎症反应通路,减轻ALI,保护肺组织。

Objective To investigate the effect of Xuebijing on activity of nuclear transcription factor -κB in the lung tissues of rabbits with blast-induced acute lung injury （ALI）, and its mechanism. Methods A total of 32 rabbits were randomly divided into 4 groups： normal control group （NS）, ALI group, Xuebijing intervention groups of different doses （L-XBJ and H-XBJ groups）. Each group had 8 rabbits. After the establishment of blast-induced ALI model of rabbits, the rabbits in the L-XBJ and H-XBJ groups were intravenously injected with different doses of Xuebijing （10 and 20 ml/kg respectively）, while the rabbits in the NS group and the ALl group were injected with normal saline of the same volume. Part of the lung tissues and venous blood were collected at the 24th hour. The wet to dry weight ratio （W/D） was determined. The serum levels of tumor necrosis factor-α （TNF-α） and interleukins （IL-6 and IL-10） were measured by enzyme-linked immunosorbent assay （ELISA）. The expression of NF-κB protein in the lung tissues was evaluated by Western blot. The expression level of NF-KB mRNA in the lung tissues was detected by reverse transcription-polymerase chain reaction （RT-PCR）. The pathological changes of the lung tissues were observed under light microscope. Results The dry to weight ratio in the L-XBJ and H-XBJ groups was lower than that of the ALI group in a concentration-dependent manner. Compared to the ALI group, Xuebijing in the treatment groups greatly inhibited the serum levels of TNF-α and IL-6 and decreased the expression of NF-κB mRNA and protein, but increased the content of IL-10. Pathological examination of the pulmonary tissues indicated severe hemorrhage, edema and abundance of inflammatory cell infiltration in the ALI group; the degree of lung damage was obviously reduced in the L-XBJ and H-XBJ groups. Conclusions The interference of Xuebijing could significantly down-regulate the levels of proinflammatory cytokines TNF-α and IL-6, up-regulate anti- inflammatory cytokine IL-10, inhibit the activation of NF-κB; thus block the inflammatory response pathway, alleviate acute lung injury and protect lung tissues.