TY - JOUR

T1 - Pulmozyme Ameliorates LPS-Induced Lung Fibrosis but Provokes Residual Inflammation by Modulating Cell-Free DNA Composition and Controlling Neutrophil Phenotype

AU - Alekseeva, Ludmila A.

AU - Sen’kova, Aleksandra V.

AU - Sounbuli, Khetam

AU - Savin, Innokenty A.

AU - Zenkova, Marina A.

AU - Mironova, Nadezhda L.

N1 - This research was funded by the Russian Science Foundation (grant no. 19-74-30011) and by the Russian State-funded budget project of ICBFM (grant no. 125012300659-6)

PY - 2025/2/17

Y1 - 2025/2/17

N2 - Pulmonary fibrosis, a chronic progressive lung disorder, can be the result of previous acute inflammation-associated lung injury and involves a wide variety of inflammatory cells, causing the deposition of extracellular matrix (ECM) components in the lungs. Such lung injury is often associated with excessive neutrophil function and the formation of DNA networks in the lungs, which are also some of the most important factors for fibrosis development. Acute lung injury with subsequent fibrosis was initiated in C57Bl/6 mice by a single intranasal (i.n.) administration of LPS. Starting from day 14, human recombinant DNase I in the form of Pulmozyme for topical administration was instilled i.n. twice a week at a dose of 50 U/mouse. Cell-free DNA (cfDNA), DNase activity, and cell content were analyzed in blood serum and bronchoalveolar lavage fluid (BALF). Inflammatory and fibrotic changes in lung tissue were evaluated by histological analysis. The gene expression profile in spleen-derived neutrophils was analyzed by RT-qPCR. We demonstrated that Pulmozyme significantly reduced connective tissue expansion in the lungs. However, despite the reliable antifibrotic effect, complete resolution of inflammation in the respiratory system of mice treated with Pulmozyme was not achieved, possibly due to enhanced granulocyte recruitment and changes in the nuclear/mitochondrial cfDNA balance in the BALF. Moreover, Pulmozyme introduction caused the enrichment of the spleen-derived neutrophil population by those with an unusual phenotype, combining pro-inflammatory and anti-inflammatory features, which can also maintain lung inflammation. Pulmozyme can be considered a promising drug for lung fibrosis management; however, the therapy may be accompanied by residual inflammation.

AB - Pulmonary fibrosis, a chronic progressive lung disorder, can be the result of previous acute inflammation-associated lung injury and involves a wide variety of inflammatory cells, causing the deposition of extracellular matrix (ECM) components in the lungs. Such lung injury is often associated with excessive neutrophil function and the formation of DNA networks in the lungs, which are also some of the most important factors for fibrosis development. Acute lung injury with subsequent fibrosis was initiated in C57Bl/6 mice by a single intranasal (i.n.) administration of LPS. Starting from day 14, human recombinant DNase I in the form of Pulmozyme for topical administration was instilled i.n. twice a week at a dose of 50 U/mouse. Cell-free DNA (cfDNA), DNase activity, and cell content were analyzed in blood serum and bronchoalveolar lavage fluid (BALF). Inflammatory and fibrotic changes in lung tissue were evaluated by histological analysis. The gene expression profile in spleen-derived neutrophils was analyzed by RT-qPCR. We demonstrated that Pulmozyme significantly reduced connective tissue expansion in the lungs. However, despite the reliable antifibrotic effect, complete resolution of inflammation in the respiratory system of mice treated with Pulmozyme was not achieved, possibly due to enhanced granulocyte recruitment and changes in the nuclear/mitochondrial cfDNA balance in the BALF. Moreover, Pulmozyme introduction caused the enrichment of the spleen-derived neutrophil population by those with an unusual phenotype, combining pro-inflammatory and anti-inflammatory features, which can also maintain lung inflammation. Pulmozyme can be considered a promising drug for lung fibrosis management; however, the therapy may be accompanied by residual inflammation.

KW - DNase I

KW - cell-free DNA

KW - lung fibrosis

KW - lung inflammation

KW - neutrophils

UR - https://www.mendeley.com/catalogue/8fcdca87-2103-3e88-a226-ac8c0afd09c9/

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85218876892&origin=inward&txGid=293fb69d201924b2697ca7f00ac117a1

UR - https://pubmed.ncbi.nlm.nih.gov/40001601/

UR - https://pmc.ncbi.nlm.nih.gov/articles/PMC11853346/

U2 - 10.3390/biom15020298

DO - 10.3390/biom15020298

M3 - Article

C2 - 40001601

VL - 15

JO - Biomolecules

JF - Biomolecules

SN - 2218-273X

IS - 2

M1 - 298

ER -