Xie Qiuwen, Shao Rongge, Xie Yongguo, Pan Linghui, Qin Ke, Du Xueke
Department of Anesthesiology, the Second Affiliated Hospital of Guangxi Medical University, Nanning 530007, Guangxi Zhuang Autonomous Region, China.
Guangxi Clinical Research Center for Anesthesiology, Guangxi Engineering Research Center for Tissue and Organ Injury and Repair Medicine, Guangxi Key Laboratory for Basic Science and Prevention of Perioperative Organ Disfunction, Nanning 530021, Guangxi Zhuang Autonomous Region, China. Corresponding author: Du Xueke, Email:
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue. 2022 Apr;34(4):383-387. doi: 10.3760/cma.j.cn121430-20210926-01401.
To investigate the role of vitamin D analogue paricalcitol in activating vitamin D receptor/glutathione peroxidase 4 (VDR/GPX4) pathway in ventilator-induced lung injury (VILI).
Twenty-four male C57BL/6J mice were randomly divided into control group, high tidal volume (HVT) induced VILI model group (HVT group), paricalcitol control group (P group), and paricalcitol pretreatment group (P+HVT group), with 6 mice in each group. The mice were endotracheal intubated and ventilated at 40 mL/kg tidal volume to prepare VILI model, while those in the control group were intubated without ventilation. The mice in the P+HVT group were intraperitoneally injected with paricalcitol 0.2 μg/kg once a day 1 week before modeling, while those in the P group were intraperitoneally injected paricalcitol 0.2 μg/kg once a day for 1 week before the experiment. After ventilation for 4 hours, the mice were sacrificed for lung tissue collection. Lung injury was evaluated by wet/dry (W/D) ratio, hematoxylin-eosin (HE) staining and Masson staining. The expressions of VDR and GPX4 were determined by Western blotting and immunohistochemistry. Malondialdehyde (MDA) and glutathione (GSH) contents were determined by micro method.
After HVT for 4 hours, compared with the control group, lung injury score and W/D ratio were significantly higher (lung injury score: 0.430±0.035 vs. 0.097±0.025, lung W/D ratio: 4.860±0.337 vs. 3.653±0.332, both P < 0.05), collagen fiber deposition was significantly increased, the content of MDA in lung tissue was significantly increased (nmol/g: 212.420±8.757 vs. 97.073±5.308, P < 0.05), GSH content and the protein expressions and immunoreactive score (IRS) of VDR and GPX4 were significantly decreased [GSH (μg/g): 44.229±1.690 vs. 70.840±0.781; VDR protein (VDR/GAPDH): 0.518±0.029 vs. 0.762±0.081, GPX4 protein (GPX4/GAPDH): 0.452±0.032 vs. 0.649±0.034; IRS score: VDR was 4.168±0.408 vs. 10.167±0.408, GPX4 was 4.333±1.033 vs. 10.333±0.516; all P < 0.05], which meant that the mice in HVT group showed obvious lung injury. After VDR was activated by paricalcitol, compared with the HVT group, lung injury score and W/D ratio were significantly decreased (lung injury score: 0.220±0.036 vs. 0.430±0.035, lung W/D ratio: 4.015±0.074 vs. 4.860±0.337, both P < 0.05), collagen fiber deposition was reduced, MDA content in lung tissue was decreased (nmol/g: 123.840±8.082 vs. 212.420±8.757, P < 0.05), GSH content and the protein expressions and IRS score of VDR and GPX4 were significantly up-regulated [GSH (μg/g): 63.094±0.992 vs. 44.229±1.690; VDR protein (VDR/GAPDH): 0.713±0.056 vs. 0.518±0.029, GPX4 protein (GPX4/GAPDH): 0.605±0.008 vs. 0.452±0.032; IRS score: VDR was 9.000±0.632 vs. 4.168±0.408, GPX4 was 8.833±0.408 vs. 4.333±1.033; all P < 0.05], which meant that lung injury in P+HVT group was significantly improved.
Vitamin D analogue paricalcitol ameliorates pulmonary oxidation-reduction imbalance by activating the VDR/GPX4 pathway, thereby alleviating VILI.
探讨维生素D类似物帕立骨化醇在呼吸机诱导的肺损伤（VILI）中激活维生素D受体/谷胱甘肽过氧化物酶4（VDR/GPX4）通路的作用。
将24只雄性C57BL/6J小鼠随机分为对照组、高潮气量（HVT）诱导的VILI模型组（HVT组）、帕立骨化醇对照组（P组）和帕立骨化醇预处理组（P+HVT组），每组6只。对小鼠进行气管插管，以40 mL/kg潮气量通气制备VILI模型，而对照组小鼠仅插管不通气。P+HVT组小鼠在建模前1周每天腹腔注射帕立骨化醇0.2 μg/kg，P组小鼠在实验前1周每天腹腔注射帕立骨化醇0.2 μg/kg。通气4小时后，处死小鼠收集肺组织。通过湿/干（W/D）比值、苏木精-伊红（HE）染色和Masson染色评估肺损伤。采用蛋白质印迹法和免疫组织化学法测定VDR和GPX4的表达。采用微量法测定丙二醛（MDA）和谷胱甘肽（GSH）含量。
HVT通气4小时后，与对照组相比，肺损伤评分和W/D比值显著升高（肺损伤评分：0.430±0.035比0.097±0.025，肺W/D比值：4.860±0.337比3.653±0.332，均P<0.05），胶原纤维沉积显著增加，肺组织中MDA含量显著增加（nmol/g：212.420±8.757比97.073±5.308，P<0.05），GSH含量以及VDR和GPX4的蛋白表达和免疫反应评分（IRS）显著降低[GSH（μg/g）：44.229±1.690比70.840±0.781；VDR蛋白（VDR/GAPDH）：0.518±0.029比0.762±0.081，GPX4蛋白（GPX4/GAPDH）：0.452±0.032比0.649±0.034；IRS评分：VDR为4.168±0.408比10.167±0.408，GPX4为4.333±1.033比10.333±0.516；均P<0.05]，这意味着HVT组小鼠出现明显的肺损伤。帕立骨化醇激活VDR后，与HVT组相比，肺损伤评分和W/D比值显著降低（肺损伤评分：0.220±0.036比0.430±0.035，肺W/D比值：4.015±0.074比4.860±0.337，均P<0.05），胶原纤维沉积减少，肺组织中MDA含量降低（nmol/g：123.840±8.082比212.420±8.757，P<0.05），GSH含量以及VDR和GPX4的蛋白表达和IRS评分显著上调[GSH（μg/g）：63.094±0.992比44.229±1.690；VDR蛋白（VDR/GAPDH）：0.713±0.056比0.518±0.029，GPX4蛋白（GPX4/GAPDH）：0.605±0.008比0.452±0.032；IRS评分：VDR为9.000±0.632比4.168±0.408，GPX4为8.833±0.408比4.333±1.033；均P<0.05]，这意味着P+HVT组的肺损伤得到显著改善。
维生素D类似物帕立骨化醇通过激活VDR/GPX4通路改善肺氧化还原失衡，从而减轻VILI。
