Experimental study on the inhibition of excessive inflammation of macrophages by postnatal elements of Lactobacillus reuteri

Objective: To investigate the therapeutic effect of extracellular vesicles on the inflammatory response mediated by macrophages RAW264.7. Method (1) Orthogonal combination of Zhibai Formula (ZBZF) and Lactobacillus reuteri (LR) co culture was used to prepare extracellular vesicles. (2) CCK-8 detects the toxicity of different concentrations of extracellular vesicles on macrophages. (3) Low (Drug-L), medium (Drug-M), and high (Drug-H) concentrations were used to intervene in macrophage inflammation models. Biochemical assay kits were used to detect NO content, qRT PCR was used to detect TNF - α, IL-6, IL-1 β, and miRlet-7c-5p expression, and ELISA was used to detect TNF - α and IL-6 secretion in cell culture media. Result (1): The prebiotic activity and synergistic LR antibacterial activity of ZBZF No. 6 were significant. (2) CCK-8 suggests that after treating macrophages with Drug-L, Drug-M, and Drug-H, the survival rates were 92.68%, 91.04%, and 82.86%, respectively. (3) After intervention of macrophages with Drug-L, Drug-M, and Drug-H, the expression of TNF - α, IL-6, and IL-1 β was downregulated, miRlet-7c-5p expression was upregulated, TNF - α and IL-6 secretion in cell culture medium decreased, NO content decreased, and Drug-H was significantly reduced. Conclusion (1) ZBZF No. 6 has prebiotic activity and synergizes with LR antibacterial activity. (2) The combination of ZBZF and LR in the preparation of extracellular vesicles can improve macrophage inflammatory response.