Department of Critical Care Medicine, Rizhao People Hospital, Rizhao, People's Republic of China.
Department of Emergency, Jinan Medical Emergency Center, Jinan, People's Republic of China.
J Invest Surg. 2021 Mar;34(3):284-296. doi: 10.1080/08941939.2019.1634165. Epub 2019 Jul 5.
The aim of the current investigation was to study the role of 3-amino-2-hydroxy-4-phenyl-valyl-isoleucine (LYRM03) in lipopolysaccharide (LPS)-induced acute lung injury (ALI) and investigate its potential pathogenesis. An LPS-induced ALI model was produced with LPS (5 mg/kg) followed by 24 h of injury. Rats were randomly assigned to 6 groups for experiments: (1) Sham, (2) LYRM03 (20 mg/kg), (3) LPS, (4) LPS plus LYRM03 (5 mg/kg), (5) LPS plus LYRM03 (10 mg/kg), and (6) LPS plus LYRM03 (20 mg/kg). The rat alveolar macrophage cell line (NR8383) cells were divided into 6 groups for experiments: (1) Sham, (2) LYRM03 (200 μmol/L), (3) LPS (100 ng/mL), (4) LPS plus LYRM03 (50 μmol/L), (5) LPS plus LYRM03 (100 μmol/L), and (6) LPS plus LYRM03 (200 μmol/L). Further study about siRNA targeting NF-κB p65, TLR4, and NLRP3 to explore the potential mechanism of LYRM03 in the LPS-induced ALI models have been done. Therefore, LYRM03 decreased LPS-induced ALI and NR8383 activation as demonstrated through hematoxylin-eosin staining and western blot analysis and . LYRM03 ameliorated the content of protein in bronchoalveolar lavage fluid, myeloperoxidase in the lung and malondialdehyde (MDA) in serum. In addition, LYRM03 ameliorated the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-18 (IL-18) in the serum of rats and the supernatant of NR8383 cells. Moreover, LYRM03 significantly inhibited the activities of nuclear factor kappa B (NF-κB), myeloid differentiation factor 88 (MyD88), and toll-like receptor 4 (TLR4). LYRM03 also reduced the increase in the inflammasome, including apoptosis-related speck-like protein containing CARD (ASC), and NOD-like receptor 3 (NLRP3), in LPS-stimulated rats and NR8383 cells. The extent of injury and lung injury scores in the LYRM03 (20 mg/kg) + siRNA targeting NF-κB p65, TLR4, or NLRP3 + LPS-treated rats were higher than that in the LYRM03 (20 mg/kg) + LPS-treated rats. In summary, LYRM03 conferred an intensely lung defensive action on LPS-induced ALI and , which could be associated with the abatement of TLR4-induced NLRP3/NF-κB.
研究 3-氨基-2-羟基-4-苯基-缬氨酰-异亮氨酸（LYRM03）在脂多糖（LPS）诱导的急性肺损伤（ALI）中的作用，并探讨其潜在的发病机制。
采用 LPS（5mg/kg）诱导 24 小时损伤建立 LPS 诱导的 ALI 模型。将大鼠随机分为 6 组进行实验：（1）Sham，（2）LYRM03（20mg/kg），（3）LPS，（4）LPS+LYRM03（5mg/kg），（5）LPS+LYRM03（10mg/kg），（6）LPS+LYRM03（20mg/kg）。
将大鼠肺泡巨噬细胞系（NR8383）细胞分为 6 组进行实验：（1）Sham，（2）LYRM03（200μmol/L），（3）LPS（100ng/mL），（4）LPS+LYRM03（50μmol/L），（5）LPS+LYRM03（100μmol/L），（6）LPS+LYRM03（200μmol/L）。进一步研究靶向 NF-κB p65、TLR4 和 NLRP3 的 siRNA，以探讨 LYRM03 在 LPS 诱导的 ALI 模型中的潜在机制。
LYRM03 降低了 LPS 诱导的 ALI 和 NR8383 的激活，通过苏木精-伊红染色和 Western blot 分析得到证实。LYRM03 改善了支气管肺泡灌洗液中蛋白的含量、肺组织中髓过氧化物酶和血清中丙二醛（MDA）的含量。此外，LYRM03 改善了大鼠血清中肿瘤坏死因子-α（TNF-α）、白细胞介素-1β（IL-1β）和白细胞介素-18（IL-18）的水平，以及 NR8383 细胞上清液中的水平。
此外，LYRM03 显著抑制了核因子 kappa B（NF-κB）、髓样分化因子 88（MyD88）和 Toll 样受体 4（TLR4）的活性。LYRM03 还降低了 LPS 刺激的大鼠和 NR8383 细胞中炎症小体（包括凋亡相关斑点样蛋白含有 CARD（ASC）和 NOD 样受体 3（NLRP3））的增加。
LYRM03（20mg/kg）+靶向 NF-κB p65、TLR4 或 NLRP3 的 siRNA+LPS 处理大鼠的损伤程度和肺损伤评分均高于 LYRM03（20mg/kg）+LPS 处理大鼠。
LYRM03 对 LPS 诱导的 ALI 具有强烈的肺保护作用，这可能与 TLR4 诱导的 NLRP3/NF-κB 的减轻有关。
