Department of Medicine, Programa de Pós-graduação em Medicina Translacional, Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.
Institute of Science and Technology, Programa de Pós-graduação em Engenharia Biomédica, Universidade Federal de São Paulo (UNIFESP), São José dos Campos, SP, Brazil.
Clinics (Sao Paulo). 2022 Mar 15;77:100021. doi: 10.1016/j.clinsp.2022.100021. eCollection 2022.
The present study investigated the anti-inflammatory effect of the probiotic Lacticaseibacillus rhamnosus (Lr) on lung inflammation induced by Lipopolysaccharide (LPS) of Escherichia coli in C57BL/6 mice.
C57BL/6 mice were divided into four groups: control, LPS, Lr (1 day) + LPS, and Lr (14 days) + LPS. Total and differential cells from Bronchoalveolar Lavage Fluid (BALF) were counted in a Neubauer 40X chamber, and pro-and anti-inflammatory cytokines (IL-1β, IL-6, CXCL-1, TNF-α, TGF-β, and IL-10) were measured by ELISA assay. The analysis of whole leukocytes in blood was performed using the automated system Sysmex 800i. Morphometry of pulmonary tissue evaluated alveolar hemorrhage, alveolar collapse, and inflammatory cells. Pulmonary vascular permeability was assessed by Evans blue dye extravasation, and bronchoconstriction was evaluated in a tissue bath station. The transcription factor NF-kB was evaluated by ELISA, and its gene expression and TLR-2, TLR-4, MMP-9, MMP-12, and TIMP by PCR.
The probiotic Lr had a protective effect against the inflammatory responses induced by LPS. Lr significantly reduced pro-inflammatory cells in the airways, lung parenchyma, and blood leukocytes. Furthermore, Lr reduced the production of pro-inflammatory cytokines and chemokines in BALF and the expression of TLRs, MMPs, and NF-kB in lung tissue and maintained the expression of TIMP in treated animals promoting a protective effect on lung tissue.
The results of the study indicate that pre-treatment with the probiotic Lr may be a promising way to mitigate lung inflammation in endotoxemia.
本研究旨在探讨益生菌鼠李糖乳杆菌（Lr）对大肠杆菌脂多糖（LPS）诱导的 C57BL/6 小鼠肺部炎症的抗炎作用。
将 C57BL/6 小鼠分为四组：对照组、LPS 组、Lr（1 天）+LPS 组和 Lr（14 天）+LPS 组。用 Neubauer 40X 室计数支气管肺泡灌洗液（BALF）中的总细胞和分类细胞，并通过 ELISA 测定促炎和抗炎细胞因子（IL-1β、IL-6、CXCL-1、TNF-α、TGF-β和 IL-10）。使用自动系统 Sysmex 800i 分析血液中的全白细胞。通过 Evans 蓝染料渗出评估肺组织的形态计量学，评估肺泡出血、肺泡塌陷和炎症细胞。通过组织浴台评估肺血管通透性和支气管收缩。通过 ELISA 评估转录因子 NF-kB，通过 PCR 评估 TLR-2、TLR-4、MMP-9、MMP-12 和 TIMP 的基因表达。
益生菌 Lr 对 LPS 诱导的炎症反应具有保护作用。Lr 显著减少气道、肺实质和血液白细胞中的促炎细胞。此外，Lr 减少了 BALF 中促炎细胞因子和趋化因子的产生，以及 TLRs、MMPs 和 NF-kB 在肺组织中的表达，并在治疗动物中维持 TIMP 的表达，从而对肺组织起到保护作用。
研究结果表明，益生菌 Lr 的预处理可能是减轻内毒素血症中肺炎症的一种有前途的方法。
