This study explored the effects of postbiotic Trifolium pratense L. on inflammatory responses in a rat model of asthma induced by lipopolysaccharide (LPS) and fumigation, with a particular focus on the dynamics of the TLR4/NF-κB signaling pathway. The experimental design involved administering LPS to the airways alongside ovalbumin sensitization to replicate chronic inflammation, followed by supplementation with postbiotics and Trifolium pratense L. leaves extract (TPLE). Quantitative analyses demonstrated that postbiotics and TPLE exerted dual regulatory effects: it downregulated systemic inflammation markers (serum IL-6, TNF-α, IL-1β) and lung-specific mucin MUC5AC, while upregulating the intestinal barrier integrity marker MUC2 in colon tissues. Mechanistic investigations indicated that postbiotics and TPLE suppressed the expression of TLR4 and NF-κB proteins in both lung and colon tissues, suggesting a comprehensive inhibition of the pathway. Furthermore, postbiotics and TPLE restored the structural integrity of alveoli and reduced the infiltration of inflammatory cells in lung parenchyma. These results imply that postbiotics and TPLE can mitigate inflammation associated with asthma through inter-organ communication, targeting shared molecular pathways within the lung- gut axis. The observed suppression of TLR4/NF-κB correlates with decreased cytokine storm activity, emphasizing the potential of postbiotics and TPLE. to interrupt pro-inflammatory signaling cascades. Additionally, the distinct regulation of mucins (MUC5AC versus MUC2) highlights tissue-specific therapeutic effects, balancing airway hypersecretion with the fortification of the intestinal barrier. This research advances the understanding of postbiotics and TPLE. as versatile agents in managing chronic respiratory diseases, presenting a novel approach to addressing systemic inflammation beyond traditional bronchodilator therapies.
KEY WORDS: Trifolium pratense L.; Postbiotic, Lung-gut axis; Asthma; TLR4; NF-κB; Inflammatory.
LI, Q. Synergistic effects of postbiotics and Trifolium pratense L. on asthmatic symptoms: Insights into the gut-lung axis and TLR4/NF-κB Pathway. Int. J. Morphol., 44(4):1205-1219, 2026.
