Abstract: Inflammation and oxidative stress play a major role in the development of sepsis and its associated complications, leading to multiple organ failure and death. The lungs, liver, and kidneys are among the early affected organs correlated with mortality in sepsis. Alpha-chymotrypsin (α-ch) is a serine protease that exerts anti-inflammatory, anti-edematous, and anti-oxidant properties.
Purpose: This study was undertaken to elucidate if the anti-inflammatory and anti-oxidant effects of α-ch observed in previous studies can alleviate lung, liver, and kidney injuries in a cecal ligation and puncture (CLP)-induced sepsis model, and thus decrease mortality.
Materials and Methods: Septic animals were given α-ch 2 h post CLP procedure. Sepsis outcomes were assessed in the lungs, liver, and kidneys. Separate animal groups were investigated for a survival study.
Results: CLP resulted in 0% survival, while α-chymotrypsin post-treatment led to 50% survival at the end of the study. Administration of α-chymotrypsin resulted in a significant attenuation of sepsis-induced elevated malonaldehyde (MDA) and total nitrite/nitrate (NOx) levels. In addition, there was a significant increase in reduced glutathione (GSH) content and superoxide dismutase (SOD) activity in the lungs, liver, and kidneys. Administration of α-ch reduced elevated tissue expression of toll-like receptor-4 (TLR4), nuclear factor kappa-B (NF-κB), myeloperoxidase (MPO), and inducible nitric oxide synthase (iNOS). Alpha-chymotrypsin resulted in a significant reduction in serum levels of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6). Alpha-chymotrypsin attenuated the rise in serum creatinine, cystatin C, blood urea nitrogen (BUN), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) levels that was observed in the septic group. In addition, α-ch significantly reduced the lung wet/dry weight ratio, total protein content, and leukocytic counts in bronchoalveolar lavage fluid (BALF). Histopathological examination of the lungs, liver, and kidneys confirmed the protective effects of α-ch on those organs.
Conclusion: α-ch has protective potential against sepsis through lowering tissue expression of TLR4, NF-κB, MPO, and iNOS leading to decreased oxidative stress and inflammatory signals induced by sepsis. This effect appeared to alleviate the damage to the lungs, liver, and kidneys and increase survival in rats subjected to sepsis.

Keywords: Sepsis, CLP, TNF-α, Cytokines, ROS, TLR-4, iNOS


中文翻译：

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α-胰凝乳蛋白酶通过抑制 TLR4/NF-κB 通路保护大鼠免受急性肺、肾和肝损伤并增加 CLP 诱导的脓毒症的存活率

摘要：炎症和氧化应激在脓毒症及其相关并发症的发展中起主要作用，导致多器官衰竭和死亡。肺、肝和肾是与败血症死亡率相关的早期受累器官。α-胰凝乳蛋白酶 (α-ch) 是一种丝氨酸蛋白酶，具有抗炎、抗水肿和抗氧化特性。
目的：本研究旨在阐明先前研究中观察到的 α-ch 的抗炎和抗氧化作用是否可以减轻盲肠结扎和穿刺 (CLP) 诱导的脓毒症模型中的肺、肝和肾损伤，以及从而降低死亡率。
材料和方法：在 CLP 手术后 2 小时给予脓毒症动物 α-ch。在肺、肝和肾中评估脓毒症结果。对不同的动物组进行了生存研究。
结果：CLP 导致 0% 的存活率，而 α-胰凝乳蛋白酶后处理导致研究结束时 50% 的存活率。施用 α-糜蛋白酶可显着降低脓毒症引起的丙二醛 (MDA) 和总亚硝酸盐/硝酸盐 (NOx) 水平升高。此外，肺、肝和肾中的还原型谷胱甘肽 (GSH) 含量和超氧化物歧化酶 (SOD) 活性显着增加。给予 α-ch 可降低 toll 样受体 4 (TLR4)、核因子 kappa-B (NF-κB)、髓过氧化物酶 (MPO) 和诱导型一氧化氮合酶 (iNOS) 的组织表达升高。α-糜蛋白酶导致肿瘤坏死因子-α (TNF-α)、白细胞介素-1 β (IL-1β) 和白细胞介素-6 (IL-6) 的血清水平显着降低。α-糜蛋白酶减弱血清肌酐、胱抑素 C、在脓毒症组中观察到的血尿素氮 (BUN)、丙氨酸氨基转移酶 (ALT) 和天冬氨酸氨基转移酶 (AST) 水平。此外，α-ch 显着降低了支气管肺泡灌洗液 (BALF) 中的肺湿/干重比、总蛋白含量和白细胞计数。肺、肝和肾的组织病理学检查证实了 α-ch 对这些器官的保护作用。
结论： α-ch通过降低组织中TLR4、NF-κB、MPO和iNOS的表达，降低脓毒症诱导的氧化应激和炎症信号，对脓毒症具有保护作用。这种作用似乎减轻了对肺、肝脏和肾脏的损害，并增加了败血症大鼠的存活率。

关键词：脓毒症，CLP，TNF-α，细胞因子，活性氧，TLR-4，iNOS