Zhu Xuejiao, Zou Yun, Wang Bing, Zhu Jiali, Chen Yi, Wang Lei, Li Jinbao, Deng Xiaoming
Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, Jiangsu, China; Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou, Jiangsu, China; Department of Anesthesiology and Intensive Care, Changhai Hospital, Second Military Medical University, Shanghai, China.
Department of Anesthesiology and Intensive Care, Changhai Hospital, Second Military Medical University, Shanghai, China.
J Surg Res. 2016 Aug;204(2):288-296. doi: 10.1016/j.jss.2016.04.067. Epub 2016 May 6.
CXCR3, a G-protein coupled chemokine receptor, has been shown to play a critical role in recruiting inflammatory cells into lungs in several studies. However, its roles in polymicrobial septic acute lung injury (ALI) is yet unknown. Therefore, the purpose of this study was to elucidate the protective effects of CXCR3 blockade on pulmonary microvascular endothelial cells (PMVECs) in septic ALI and explore potential mechanisms.
ALI was induced by polymicrobial sepsis through cecal ligation and puncture surgery. The expression of CXCR3 on pulmonary microvascular endothelial cells was measured 24 h after cecal ligation and puncture surgery. In addition, the protective effects of neutralizing antibody were detected, including protein concentration, inflammation cell counts, lung wet-to-dry ratio, and lung damages. In human umbilical vein endothelial cells (HUVECs) culture condition, CXCR3 expression was measured after exposure to tumor necrosis factor-α. The permeability and apoptosis ratio were detected through CXCR3 gene silencing on HUVECs. The p38 mitogen-activated protein kinase (MAPK) was analyzed with Western blot.
CXCR3 expression was upregulated both in vivo and in vitro. After CXCR3 neutralizing antibody administrated intraperitoneally, the protein concentration, inflammatory cell counts in BALF and lung wet-to-dry ratio were decreased significantly, as well as the lung tissue damages. In vitro, CXCR3 gene silencing inhibited tumor necrosis factor-α and CXCL10-induced hyperpermeability and apoptosis in HUVECs. In addition, p38 mitogen-activated protein kinase activation was essential for CXCR3-mediated apoptosis.
CXCR3 blockade exerts protective effects on ALI at least partly by inhibiting endothelial cells apoptosis and decreasing the leakage of protein-rich fluid and inflammatory cells. Blockade of CXCR3 may be a promising therapeutic strategy for severe sepsis-induced ALI.
CXCR3是一种G蛋白偶联趋化因子受体，多项研究表明其在炎症细胞募集至肺脏过程中发挥关键作用。然而，其在多微生物脓毒症急性肺损伤（ALI）中的作用尚不清楚。因此，本研究旨在阐明CXCR3阻断对脓毒症ALI肺微血管内皮细胞（PMVECs）的保护作用，并探索潜在机制。
通过盲肠结扎和穿刺手术诱导多微生物脓毒症致ALI。在盲肠结扎和穿刺手术后24小时测量肺微血管内皮细胞上CXCR3的表达。此外，检测中和抗体的保护作用，包括蛋白浓度、炎症细胞计数、肺湿干比和肺损伤情况。在人脐静脉内皮细胞（HUVECs）培养条件下，暴露于肿瘤坏死因子-α后测量CXCR3表达。通过对HUVECs进行CXCR3基因沉默检测通透性和凋亡率。用蛋白质印迹法分析p38丝裂原活化蛋白激酶（MAPK）。
CXCR3在体内和体外均上调表达。腹腔注射CXCR3中和抗体后，蛋白浓度、支气管肺泡灌洗液中的炎症细胞计数和肺湿干比显著降低，肺组织损伤也减轻。在体外，CXCR3基因沉默抑制肿瘤坏死因子-α和CXCL10诱导的HUVECs高通透性和凋亡。此外，p38丝裂原活化蛋白激酶激活对CXCR3介导的凋亡至关重要。
CXCR3阻断至少部分通过抑制内皮细胞凋亡以及减少富含蛋白质液体和炎症细胞的渗漏对ALI发挥保护作用。阻断CXCR3可能是治疗严重脓毒症诱导的ALI的一种有前景的治疗策略。
