Liver Failure Group, UCL Institute for Liver and Digestive Health, Royal Free Hospital, London, United Kingdom.
Liver Transpl. 2013 Jul;19(7):751-61. doi: 10.1002/lt.23655.
Strategies for the prevention of multiorgan dysfunction (MOD) in acetaminophen (APAP)-induced acute liver failure (ALF) are an unmet need. Our study tested the hypothesis that sterile inflammation induced by APAP in a mouse model would activate toll-like receptor 4 (TLR4) in the liver and extrahepatic organs and lead to the progression of ALF and MOD and that the administration of the novel TLR4 antagonist STM28 (a peptide formed of 17 amino-acids) would prevent liver injury and associated MOD. ALF and, subsequently, MOD were induced in TLR4-knockout (KO) mice (B6.B10ScN-Tlr4 (lpsdel) /JthJ) and wild-type (WT) mice (C57BL/6) with APAP (500 mg/kg). A second set of experiments was conducted to evaluate the effects of a pretreatment with a novel TLR4 antagonist, STM28, on APAP-induced MOD in CD1 mice. Animals were sacrificed at the coma stage, and plasma, peripheral blood cells, liver, kidneys, and brain were collected. Biochemistry values and cytokines were measured. Liver and kidneys were studied histologically and were stained for TLR4 and activated Kupffer cells, and the expression of nuclear factor kappa B-p65 was quantified with western blotting. Brain water was measured in the frontal cortex. After APAP administration, TLR4-KO (NFkBp65) mice were relatively protected from liver necrosis and end-organ dysfunction and had significantly better survival than WT controls (P < 0.01). STM28 attenuated liver injury and necrosis, reduced creatinine levels, and delayed the time to a coma significantly. The increases in cytokines in the plasma and liver, including TLR4 expression and the activation of Kupffer cells, after APAP administration were reduced significantly in the STM28-treated animals. The increased number of circulating myeloid cells was reduced significantly after STM28 treatment. In conclusion, these data provide evidence for an important role of the TLR4 antagonist in the prevention of the progression of APAP-induced ALF and MOD.
策略，以防止多器官功能障碍（MOD）在对乙酰氨基酚（APAP）诱导的急性肝衰竭（ALF）是一个未满足的需要。我们的研究检验了这样一个假设，即 APAP 在小鼠模型中诱导的无菌性炎症将激活肝和肝外器官中的 Toll 样受体 4（TLR4），并导致 ALF 和 MOD 的进展，而新型 TLR4 拮抗剂 STM28（由 17 个氨基酸组成的肽）的给药将预防肝损伤和相关的 MOD。用 APAP（500mg/kg）在 TLR4 敲除（KO）小鼠（B6.B10ScN-Tlr4（lpsdel）/JthJ）和野生型（WT）小鼠（C57BL/6）中诱导 ALF 和随后的 MOD。进行了第二组实验，以评估新型 TLR4 拮抗剂 STM28 预处理对 CD1 小鼠 APAP 诱导的 MOD 的影响。动物在昏迷阶段被处死，收集血浆、外周血细胞、肝、肾和脑。测量生化值和细胞因子。对肝和肾进行组织学研究，并对 TLR4 和活化的枯否细胞进行染色，并用 Western 印迹定量核因子 kappa B-p65 的表达。测量额皮质中的脑水。在 APAP 给药后，TLR4-KO（NFkBp65）小鼠相对受到保护，免受肝坏死和终末器官功能障碍的影响，与 WT 对照相比，存活率显著提高（P<0.01）。STM28 显著减轻肝损伤和坏死，降低肌酐水平，并显著延迟昏迷时间。APAP 给药后，血浆和肝脏中细胞因子的增加，包括 TLR4 的表达和枯否细胞的激活，在 STM28 治疗的动物中显著减少。STM28 治疗后，循环髓样细胞的数量显著减少。总之，这些数据为 TLR4 拮抗剂在预防 APAP 诱导的 ALF 和 MOD 进展中的重要作用提供了证据。
