Wang Si-Si, Xie Shuang-Shuang, Meng Yue-Xiu, Zhang Xiang-Yun, Liu Yun-Chun, Wang Ling-Ling, Wang Yan-Fei
Department of Obstetrics and Gynecology, First Hospital Affiliated to Hebei North University, Zhangjiakou, Hebei 075000, China.
Zhongguo Dang Dai Er Ke Za Zhi. 2023 Feb 15;25(2):193-201. doi: 10.7499/j.issn.1008-8830.2208010.
To study the protective effect of breviscapine against brain injury induced by intrauterine inflammation in preterm rats and its mechanism.
A preterm rat model of brain injury caused by intrauterine inflammation was prepared by intraperitoneal injections of lipopolysaccharide in pregnant rats. The pregnant rats and preterm rats were respectively randomly divided into 5 groups: control, model, low-dose breviscapine (45 mg/kg), high-dose breviscapine (90 mg/kg), and high-dose breviscapine (90 mg/kg)+ML385 [a nuclear factor erythroid 2-related factor 2 (Nrf2) inhibitor, 30 mg/kg] (=10 each). The number and body weight of the live offspring rats were measured for each group. Hematoxylin-eosin staining was used to observe the pathological morphology of the uterus and placenta of pregnant rats and the pathological morphology of the brain tissue of offspring rats. Immunofluorescent staining was used to measure the co-expression of ionized calcium binding adaptor molecule-1 (IBA-1) and nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) in the cerebral cortex of offspring rats. ELISA was used to measure the levels of interleukin-6 (IL-6), interleukin-8 (IL-8), and interleukin-1β (IL-1β) in the brain tissue of offspring rats. Western blotting was used to measure the expression of Nrf2 pathway-related proteins in the brain tissue of offspring rats.
Pathological injury was found in the uterus, and placenta tissue of the pregnant rats and the brain tissue of the offspring rats, and severe microglia pyroptosis occurred in the cerebral cortex of the offspring rats in the model group. Compared with the control group, the model group had significant reductions in the number and body weight of the live offspring rats and the protein expression levels of Nrf2 and heme oxygenase-1 (HO-1) in the brain tissue of the offspring rats (<0.05), but significant increases in the relative fluorescence intensity of the co-expression of IBA-1 and NLRP3, the levels of the inflammatory factors IL-6, IL-8, and IL-1β, and the protein expression levels of NLRP3 and caspase-1 in the brain tissue of the offspring rats (<0.05). Compared with the model group, the breviscapine administration groups showed alleviated pathological injury of the uterus and placenta tissue of the pregnant rats and the brain tissue of the offspring rats, significant increases in the number and body weight of the live offspring rats and the protein expression levels of Nrf2 and HO-1 in the brain tissue of the offspring rats (<0.05), and significant reductions in the relative fluorescence intensity of the co-expression of IBA-1 and NLRP3, the levels of the inflammatory factors IL-6, IL-8, and IL-1β, and the protein expression levels of NLRP3 and caspase-1 in the brain tissue of the offspring rats (<0.05). The high-dose breviscapine group had a significantly better effect than the low-dose breviscapine (<0.05). ML385 significantly inhibited the intervention effect of high-dose breviscapine (<0.05).
Breviscapine can inhibit inflammatory response in brain tissue of preterm rats caused by intrauterine inflammation by activating the Nrf2 pathway, and it can also inhibit microglial pyroptosis and alleviate brain injury.
研究灯盏花素对早产大鼠宫内炎症诱导的脑损伤的保护作用及其机制。
通过给孕鼠腹腔注射脂多糖制备宫内炎症所致脑损伤的早产大鼠模型。将孕鼠和早产大鼠分别随机分为5组：对照组、模型组、低剂量灯盏花素组（45 mg/kg）、高剂量灯盏花素组（90 mg/kg）、高剂量灯盏花素组（90 mg/kg）+ML385 [一种核因子红细胞2相关因子2（Nrf2）抑制剂，30 mg/kg]（每组各10只）。测量每组存活仔鼠的数量和体重。采用苏木精-伊红染色观察孕鼠子宫和胎盘的病理形态以及仔鼠脑组织的病理形态。采用免疫荧光染色检测仔鼠大脑皮质中离子钙结合衔接分子-1（IBA-1）和核苷酸结合寡聚化结构域样受体蛋白3（NLRP3）的共表达情况。采用酶联免疫吸附测定法检测仔鼠脑组织中白细胞介素-6（IL-6）、白细胞介素-8（IL-8）和白细胞介素-1β（IL-1β）的水平。采用蛋白质免疫印迹法检测仔鼠脑组织中Nrf2通路相关蛋白的表达。
孕鼠的子宫和胎盘组织以及仔鼠的脑组织均出现病理损伤，模型组仔鼠大脑皮质发生严重的小胶质细胞焦亡。与对照组相比，模型组存活仔鼠的数量和体重以及仔鼠脑组织中Nrf2和血红素加氧酶-1（HO-1）的蛋白表达水平显著降低（<0.05），但仔鼠脑组织中IBA-1和NLRP3共表达的相对荧光强度、炎症因子IL-6、IL-8和IL-1β的水平以及NLRP3和半胱天冬酶-1的蛋白表达水平显著升高（<0.05）。与模型组相比，灯盏花素给药组孕鼠子宫和胎盘组织以及仔鼠脑组织的病理损伤减轻，存活仔鼠的数量和体重以及仔鼠脑组织中Nrf2和HO-1的蛋白表达水平显著升高（<0.05），仔鼠脑组织中IBA-1和NLRP3共表达的相对荧光强度、炎症因子IL-6、IL-8和IL-1β的水平以及NLRP3和半胱天冬酶-1的蛋白表达水平显著降低（<0.05）。高剂量灯盏花素组的效果显著优于低剂量灯盏花素组（<0.05）。ML385显著抑制高剂量灯盏花素的干预效果（<0.05）。
灯盏花素可通过激活Nrf2通路抑制早产大鼠宫内炎症所致脑组织的炎症反应，还可抑制小胶质细胞焦亡并减轻脑损伤。
