This study was conducted to investigate the effects of glycerol monolaurate (GML) on lipopolysaccharide (LPS)-induced immunological stress and intestinal mucosal injury in broilers and its underlying mechanisms. A total of 144 one-d-old Arbor Acres broilers were allocated to a 2 × 2 factorial arrangement involving dietary treatment (0 or 1,200 mg/kg dietary GML) and LPS challenge (injected with saline or Escherichia coli LPS on d 16, 18, and 20). Samples were collected on d 21. The results revealed that dietary GML augmented serum immunoglobulin A (P = 0.009) and immunoglobulin G (P < 0.001) levels in challenged birds. Dietary GML normalized LPS-induced variations in serum interleukin-6, interferon-gamma, and LPS levels (P < 0.05), jejunal villus height (P = 0.030), and gene expression of interleukin-6, macrophage inflammatory protein-3 alpha, Toll-like receptor 4, nuclear factor kappa-B, caspase-1, tight junction proteins, adenosine monophosphate-activated protein kinase alpha 1 (AMPKα1), nuclear factor-erythroid 2-related factor 2 (Nrf2), and superoxide dismutase-1 (P < 0.05). GML supplementation ameliorated LPS-induced peroxidation by reducing malondialdehyde content and increasing antioxidant enzyme activity (P < 0.05). Dietary GML enhanced the abundances of Anaerostipes, Pseudoflavonifractor, and Gordonibacter and reduced the proportion of Phascolarctobacterium in challenged birds. Dietary GML was positively correlated with alterations in antioxidant enzyme activities and AMPKα1, Nrf2, and zonula occludens-1 expressions. The genera Anaerostipes, Lachnospira, Gordonibacter, Lachnospira, Marvinbryantia, Peptococcus, and Pseudoflavonifractor were linked to attenuated inflammation and improved antioxidant capacity of challenged birds. In conclusion, dietary GML alleviated LPS-induced immunological stress and intestinal injury of broilers by suppressing inflammation and oxidative stress. Dietary GML regulated cecal microbiota and activated the AMPK/Nrf2 pathway in LPS-challenged broilers.

本研究旨在探讨单月桂酸甘油酯 (GML) 对脂多糖 (LPS) 诱导的肉鸡免疫应激和肠黏膜损伤的影响及其潜在机制。总共 144 只 1 日龄 Arbor Acres 肉鸡被分配到 2 × 2 因子排列，包括日粮处理（0 或 1,200 mg/kg 日粮 GML）和 LPS 攻击（在第 16 天、第 18 天注射盐水或大肠杆菌LPS , 和 20)。在第 21 天收集样品。结果显示，日粮 GML 提高了受攻击鸡只的血清免疫球蛋白 A ( P  = 0.009) 和免疫球蛋白 G ( P  < 0.001) 水平。膳食 GML 使 LPS 诱导的血清白细胞介素 6、干扰素 γ 和 LPS 水平的变化正常化（P < 0.05)、空肠绒毛高度 ( P  = 0.030)、白细胞介素 6、巨噬细胞炎症蛋白 3 α、Toll 样受体 4、核因子 kappa-B、caspase-1、紧密连接蛋白、一磷酸腺苷的基因表达活化蛋白激酶 α1 ( AMPKα1 )、核因子-红细胞 2 相关因子 2 ( Nrf2 ) 和超氧化物歧化酶-1 ( P  < 0.05)。GML 补充剂通过降低丙二醛含量和增加抗氧化酶活性来改善 LPS 诱导的过氧化反应（P  < 0.05）。日粮 GML 提高了Anaerostipes、Pseudoflavonifractor和Gordonibacter的丰度并降低了受攻击鸟类中的芽孢杆菌属。膳食 GML 与抗氧化酶活性和AMPKα1、Nrf2和 zonula occludens -1 表达的变化呈正相关。Anaerostipes属, Lachnospira , Gordonibacter , Lachnospira , Marvinbryantia , Peptococcus ,和Pseudoflavonifractor与减轻炎症和提高受攻击鸟类的抗氧化能力有关。总之，日粮 GML 通过抑制炎症和氧化应激来减轻 LPS 诱导的肉鸡免疫应激和肠道损伤。日粮 GML 调节盲肠微生物群并激活 LPS 攻击肉鸡中的 AMPK/Nrf2 通路。