Wan Jia, Yu Xi, Niu Jia-Qi, Qiu Le, Wang Fei, Chen Xu-Lin
Department of Burns, The First Affiliated Hospital of Anhui Medical University, Hefei, China.
Front Med (Lausanne). 2022 Feb 24;9:809289. doi: 10.3389/fmed.2022.809289. eCollection 2022.
This study aimed to investigate the role and molecular mechanisms of Bruton's tyrosine kinase (BTK), a member of the Tec family in burn sepsis-induced intestinal injury. Eighty C57BL/6 mice were randomly divided into four groups: the sham group, the burn group, the burn + sepsis group, and the burn + sepsis + LFM-A13 (a selective BTK inhibitor) group. The dynamic expression profiles of BTK and p-BTK in the intestine were measured by Western blot analysis. Intestinal histopathological changes and cellular apoptosis were determined. Inflammatory cytokines in serum and intestinal tissue were examined through enzyme-linked immunosorbent assay. Myeloperoxidase (MPO) activity was determined a colorimetric assay. Intestinal p-BTK expression in the burn+sepsis group was significantly increased compared with that in the sham and burn groups. In the burn + sepsis group, the p-BTK expression level increased over time, peaked at 12, and then decreased at 24 h. LFM-A13 administration significantly inhibited p-BTK expression in the intestine. In contrast to the sham and burn groups, the burn + sepsis group exhibited obvious histopathological changes, which gradually aggravated over time. LFM-A13 also reduced the histopathological changes and cellular apoptosis in intestinal tissues, inhibited the inflammatory cytokines IL-4, IL-6, and TNF-α in serum and intestinal tissues, and significantly inhibited the increase in intestinal MPO activity induced by burn sepsis. BTK activation is one important aspect of the signaling event that may mediate the release of the anti-inflammatory cytokine IL-4 and the pro-inflammatory cytokines IL-6 and TNF-α; oxidative stress; and intestinal cell apoptosis. Thus, it contributes to burn sepsis-induced intestinal injury.
本研究旨在探讨Tec家族成员布鲁顿酪氨酸激酶（BTK）在烧伤脓毒症诱导的肠道损伤中的作用及分子机制。80只C57BL/6小鼠随机分为四组：假手术组、烧伤组、烧伤+脓毒症组和烧伤+脓毒症+LFM-A13（一种选择性BTK抑制剂）组。通过蛋白质免疫印迹分析测定肠道中BTK和磷酸化BTK（p-BTK）的动态表达谱。确定肠道组织病理学变化和细胞凋亡情况。通过酶联免疫吸附测定法检测血清和肠道组织中的炎性细胞因子。采用比色法测定髓过氧化物酶（MPO）活性。与假手术组和烧伤组相比，烧伤+脓毒症组肠道p-BTK表达显著增加。在烧伤+脓毒症组中，p-BTK表达水平随时间升高，在12小时达到峰值，随后在24小时下降。给予LFM-A13可显著抑制肠道中p-BTK的表达。与假手术组和烧伤组相比，烧伤+脓毒症组呈现明显的组织病理学变化，且随时间逐渐加重。LFM-A13还减轻了肠道组织的组织病理学变化和细胞凋亡，抑制了血清和肠道组织中炎性细胞因子白细胞介素-4（IL-4）、白细胞介素-6（IL-6）和肿瘤坏死因子-α（TNF-α）的产生，并显著抑制了烧伤脓毒症诱导的肠道MPO活性升高。BTK激活是信号转导事件的一个重要方面，可能介导抗炎细胞因子IL-4和促炎细胞因子IL-6及TNF-α的释放、氧化应激和肠道细胞凋亡。因此，它促成了烧伤脓毒症诱导的肠道损伤。
