Protective role of endothelial calpain knockout in lipopolysaccharide-induced acute kidney injury via attenuation of the p38-iNOS pathway and NO/ROS production
Protective role of endothelial calpain knockout in lipopolysaccharide-induced acute kidney injury via attenuation of the p38-iNOS pathway and NO/ROS production
复制标题
内皮钙蛋白酶敲除通过减弱 p38-iNOS 途径和 NO/ROS 产生对脂多糖诱导的急性肾损伤的保护作用
DOI：
10.1038/s12276-020-0426-9
复制
发表时间：
2020-04-28
影响因子：
12.8
通讯作者：
Tang, Jing
中科院分区：
文献类型：
--
作者：
Liu, Zhifeng;Ji, Jingjing;Tang, Jing
为了探讨calpain及其信号通路在脂多糖（LPS）诱导的急性肾损伤（AKI）中的作用，通过LPS对内皮特异性Capn4敲除小鼠（TEK/Capn4(-/-)）、内源性calpain抑制剂calpastatin过表达小鼠（Tg-CAST）和骨髓特异性Capn4敲除小鼠（LYZ/Capn4(-/-)）建立内毒素血症动物模型。以小鼠肺微血管内皮细胞（pmec）为模型，采用LPS对其进行刺激。检测肾功能、肾诱导型一氧化氮合酶（iNOS）和内皮型一氧化氮合酶（eNOS）表达、细胞凋亡、血浆和肾脏NO和活性氧（ROS）水平以及丝裂原活化蛋白激酶（MAPK）家族成员（p38、ERK1/2和JNK1/2）磷酸化水平。此外，还使用了calpain抑制剂、calpastatin过表达腺病毒和MAPK抑制剂。LPS刺激引起明显的肾功能障碍，TEK/Capn4（-/-）和Tg-CAST小鼠肾功能恢复，LYZ/Capn4（-/-）小鼠肾功能恢复。内皮细胞Capn4敲除也消除了lps诱导的肾脏iNOS表达、caspase-3活性、凋亡以及血浆和肾脏NO和ROS水平的升高，但对肾脏eNOS表达没有明显影响。此外，LPS增加了calpain和caspase-3活性，pmec中只有iNOS的表达伴随着p38和JNK磷酸化的增加。抑制calpain活性或p38磷酸化可减轻LPS诱导的iNOS表达升高、NO/ROS生成和细胞凋亡。这些结果表明，内皮calpain通过抑制p38磷酸化在lps诱导的AKI中发挥保护作用，从而减弱iNOS的表达，进一步减少NO和ROS过度产生诱导的内皮细胞凋亡。急性肾损伤：酶阻滞可以对抗衰竭根据中国和加拿大的研究人员的研究，抑制钙蛋白酶的治疗可以减轻急性肾损伤的影响。急性肾损伤是由内毒素血症引起的，在内毒素血症中，肠道通透性的改变允许脂多糖（LPS）从肠道细菌进入血液。已知Calpain在这一过程中是活跃的。广州军区总医院刘志峰等通过注射LPS诱导多种模型小鼠内毒素血症。LPS诱导了显著的肾功能障碍和细胞死亡，但在经过基因修饰以阻断血管内膜钙蛋白酶活性的小鼠和过度表达钙蛋白酶抑制剂钙pastatin的小鼠中，这些症状得到了缓解。阻断钙蛋白酶可降低损伤内皮细胞的一氧化氮合酶的表达。
To explore the role of calpain and its signaling pathway in lipopolysaccharide (LPS)-induced acute kidney injury (AKI), animal models of endotoxemia were established by administration of LPS to mice with endothelial-specific Capn4 knockout (TEK/Capn4(-/-)), mice with calpastatin (an endogenous calpain inhibitor) overexpression (Tg-CAST) and mice with myeloid-specific Capn4 knockout (LYZ/Capn4(-/-)). Mouse pulmonary microvascular endothelial cells (PMECs) were used as a model of the microvascular endothelium and were stimulated with LPS. Renal function, renal inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS) expression, cellular apoptosis, plasma and renal levels of NO and reactive oxygen species (ROS), and phosphorylation of mitogen-activated protein kinase (MAPK) family members (p38, ERK1/2, and JNK1/2) were examined. Moreover, a calpain inhibitor, calpastatin overexpression adenoviruses and MAPK inhibitors were used. Significant renal dysfunction was induced by LPS stimulation, and recovery was observed in TEK/Capn4(-/-) and Tg-CAST mice but not in LYZ/Capn4(-/-) mice. Endothelial Capn4 knockout also abrogated the LPS-induced increases in renal iNOS expression, caspase-3 activity and apoptosis and plasma and renal NO and ROS levels but did not obviously affect renal eNOS expression. Moreover, LPS increased both calpain and caspase-3 activity, and only the expression of iNOS in PMECs was accompanied by increased phosphorylation of p38 and JNK. Inhibiting calpain activity or p38 phosphorylation alleviated the increased iNOS expression, NO/ROS production, and cellular apoptosis induced by LPS. These results suggest that endothelial calpain plays a protective role in LPS-induced AKI by inhibiting p38 phosphorylation, thus attenuating iNOS expression and further decreasing NO and ROS overproduction-induced endothelial apoptosis.Acute kidney injury: enzyme block could combat failure Therapies that inhibit the enzyme calpain could alleviate the effects of acute kidney injury according to researchers in China and Canada. Acute kidney injury is induced by endotoxemia, in which changes in the permeability of the intestine allow lipopolysaccharides (LPS) to pass from gut bacteria into the bloodstream. Calpain is known to be active during this process. Zhifeng Liu at the General Hospital of Guangzhou Military Command and co-workers induced endotoxemia in various mouse models by injecting them with LPS. The LPS induced significant kidney dysfunction and cell death, but these were alleviated in mice that were genetically modified to block calpain activity in the blood vessel lining, and in mice that overexpressed calpastatin, a calpain inhibitor. Blocking calpain reduces the expression of nitric oxide synthases that damage endothelial cells.