叔丁基对苯二酚对急性肺损伤小鼠的保护作用

Protective effect of tert-butylhydroquinone on mice with acute lung injury

关键词:  急性肺损伤  急性呼吸窘迫综合征  叔丁基对苯二酚  核外转录因子NF-E2相关因子  炎症反应

Key words:  acute lung injury  acute respiratory distress syndrome  tert-butylhydroquinone  nuclear factor E2-related factor 2  immune response

摘要:

目的 探究叔丁基对苯二酚（tBHQ）在急性肺损伤（acute lung injury, ALI）中调节炎症反应的作用和机制。方法 通过腹腔注射脂多糖（LPS）建立C57BL/6J小鼠ALI模型，将C57BL/6J雄性小鼠随机分组。LPS组小鼠按两种剂量（10mg/kg和20mg/kg）腹腔注射,高剂量组观察小鼠生存率，低剂量组观察炎症反应；磷酸盐缓冲液（PBS）组小鼠给予等体积PBS腹腔注射；tBHQ+LPS/tBHQ组小鼠预先24h腹腔给予tBHQ并在LPS处理的同时给予tBHQ；LPS/tBHQ组小鼠在LPS处理的同时给予tBHQ。监测7d生存率；LPS诱导3h后病理组织学观察评估其肺组织损伤程度，实时定量PCR（RT-qPCR）和多重液相蛋白定量技术分别检测小鼠肺组织和血清中IL-6、TNF-α和IL-10的水平，Western印迹法和RT-qPCR检测各组小鼠肺组织中核外转录因子NF-E2相关因子（Nrf2）的表达。结果 与LPS组相比,LPS/tBHQ组和tBHQ+LPS/tBHQ组小鼠的死亡率均明显降低（P分别为0.0005和0.0001），并且小鼠肺组织损伤程度明显减轻，小鼠肺组织和血清中促炎症介质IL-6和TNF-α的表达降低，抗炎介质IL-10的表达增加；同时与LPS组相比，tBHQ可明显增加肺组织中Nrf2的mRNA水平以及核内蛋白水平。结论 tBHQ能够通过调节小鼠肺组织中促炎、抑炎反应平衡发挥对ALI的保护作用，其机制可能与促进Nrf2核转位有关。

Abstract:

Objective To investigate the effect of tert-butylhydroquinone(tBHQ) on immune response of mice with acute lung injury(ALI). Methods The mouse model of acute lung injury was established by intraperitoneal injection of lipopolysaccharide(LPS). C57BL/6J male mice were randomly divided into 4 groups. The mice in LPS group were injected intraperitoneally with two doses of LPS(10mg/kg and 20mg/kg); the mice in PBS group were given intraperitoneal injection with equal volume of PBS; the mice in tBHQ+LPS/tBHQ group were given tBHQ intraperitoneally 24h in advance and at the same time with LPS induction; the LPS/tBHQ mice were given tBHQ with LPS induction. The 7-d survival rate was monitored. The lung injury in mice was assessed 3h after LPS induction. Real-time quantitative PCR(RT-qPCR) and cytometric beads array(CBA) were used to detect the levels of IL-6, TNF-α and IL-10 in the lung tissues and serum of mice, respectively. Western blotting and real-time quantitative PCR were used to detect the expression of transcription factor NF-E2-related factor(Nrf2) in lung tissues. Results Compared with the LPS group, the mortality of the LPS/tBHQ group and the tBHQ+LPS/tBHQ group were significantly lower(P=0.0005 and 0.0001, respectively), and the lung tissue damage was drastically alleviated. The expression of pro-inflammatory mediators IL-6 and TNF-α was decreased in the lung tissues and serum, and the expression of anti-inflammatory mediators IL-10 was increased. Compared with the LPS single treatment group, tBHQ significantly increased Nrf2 mRNA levels and nuclear protein levels in the lung tissue. Conclusion Tert-butylhydroquinone can protect mice against the acute lung injury by regulating the balance of pro-inflammatory and anti-inflammatory responses. The mechanism may be related to the promotion of nuclear translocation of Nrf2.