Modulating Effect of Peptide Therapy on the Morphofunctional State of Bronchial Epithelium in Rats with Obstructive Lung Pathology

This experimental study investigated the effects of Bronchogen (Ala-Asp-Glu-Leu), a bioregulatory tetrapeptide from the Khavinson peptide class, on bronchial epithelium in a chronic obstructive pulmonary disease (COPD) model in rats. COPD was induced by chronic exposure to tobacco smoke and administration of bacterial lipopolysaccharides, simulating the conditions of the human disease.

Rats treated with Bronchogen showed elimination of pathological remodeling signs of the bronchial epithelium that characterize COPD: goblet cell hyperplasia (mucus-producing cells), loss of ciliated cells, and basement membrane thickening. The peptide promoted the restoration of ciliated cells of the respiratory epithelium — essential for mucociliary clearance — reversing one of the central mechanisms of COPD pathogenesis.

In the immunological assessment, Bronchogen normalized secretory IgA levels (the main immunoglobulin for respiratory mucosal defense) and reduced the concentrations of pro-inflammatory cytokines (TNF-alpha, IL-6) in bronchoalveolar lavage. This indicates local immunological modulation that promotes the resolution of chronic inflammation without immunosuppression.

The study is significant in the context of the Russian school of peptide bioregulation, demonstrating that short tissue-specific peptides can reverse pathological morphological changes in target organs. Bronchogen represents an example of how peptides of only 4 amino acids can modulate gene expression and cell differentiation in specific tissues, in this case the bronchopulmonary epithelium.