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Nicola, T.

Publications and source records attributed to Nicola, T..

3 recordsLinked to original sources

Antimicrobial peptides modulate pulmonary inflammation by altering the intestinal microbiota

Mammalian mucosal barriers secrete antimicrobial peptides (AMPs) as critical host-derived regulators of the microbiota. However, mechanisms that support homeostasis of the microbiota in response to inflammatory stimuli such as supraphysiologic oxygen remain unclear. Here, we show that neonatal mice breathing supraphysiologic oxygen or direct exposure of intestinal organoids to supraphysiologic oxygen suppress the intestinal expression of AMPs and alters the composition of the intestinal microbiota. Oral supplementation of the prototypical AMP lysozyme to hyperoxia exposed neonatal mice reduced hyperoxia-induced alterations in their microbiota and was associated with decreased lung injury. Our results identify a gut-lung axis driven by intestinal AMP expression and mediated by the intestinal microbiota that is linked to lung injury. Together, these data support that intestinal AMPs modulate lung injury and repair. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=185 SRC="FIGDIR/small/529700v2_ufig1.gif" ALT="Figure 1"> View larger version (66K): org.highwire.dtl.DTLVardef@800123org.highwire.dtl.DTLVardef@1caac5forg.highwire.dtl.DTLVardef@faa875org.highwire.dtl.DTLVardef@49c4e9_HPS_FORMAT_FIGEXP M_FIG C_FIG In BriefUsing a combination of murine models and organoids, Abdelgawad and Nicola et al. find that suppression of antimicrobial peptide release by the neonatal intestine in response to supra-physiological oxygen influences the progression of lung injury likely via modulation of the ileal microbiota. HighlightsO_LISupraphysiologic oxygen exposure alters intestinal antimicrobial peptides (AMPs). C_LIO_LIIntestinal AMP expression has an inverse relationship with the severity of lung injury. C_LIO_LIAMP-driven alterations in the intestinal microbiota form a gut-lung axis that modulates lung injury. C_LIO_LIAMPs may mediate a gut-lung axis that modulates lung injury. C_LI

microbiology↗

Platelet Activating Factor Activity Modulates Hyperoxic Neonatal Lung Injury Severity

Hyperoxia-induced inflammation contributes significantly to developmental lung injury and bronchopulmonary dysplasia (BPD) in preterm infants. Platelet activating factor (PAF) is known to be a major driver of inflammation in lung diseases such as asthma and pulmonary fibrosis, but its role in BPD has not been previously investigated. Therefore, to determine whether PAF signaling independently modulates neonatal hyperoxic lung injury and BPD pathogenesis, lung structure was assessed in 14 day-old C57BL/6 wild-type (WT) and PAF receptor knockout (PTAFR KO) mice that were exposed to 21% (normoxia) or 85% O2 (hyperoxia) from postnatal day 4. Lung morphometry showed that PTAFR KO mice had attenuated hyperoxia-induced alveolar simplification when compared to WT mice. Functional analysis of gene expression data from hyperoxia-exposed vs. normoxia-exposed lungs of WT and PTAFR KO showed that the most upregulated pathways were the hypercytokinemia/hyperchemokinemia pathway in WT mice, NAD signaling pathway in PTAFR KO mice, and agranulocyte adhesion and diapedesis as well as other pro-fibrotic pathways such as tumor microenvironment and oncostatin-M signaling in both mice strains, indicating that PAF signaling may contribute to inflammation but may not be a significant mediator of fibrotic processes during hyperoxic neonatal lung injury. Gene expression analysis also indicated increased expression of pro-inflammatory genes such as CXCL1, CCL2 and IL-6 in the lungs of hyperoxia-exposed WT mice and metabolic regulators such as HMGCS2 and SIRT3 in the lungs of PTAFR KO mice, suggesting that PAF signaling may modulate BPD risk through changes in pulmonary inflammation and/or metabolic reprogramming in preterm infants.

pathology↗

Neutrophilic Inflammation in Models of Bronchopulmonary Dysplasia and Chronic Obstructive Pulmonary Disease is Rescued by a Lactobacilli Based Live Biotherapeutic

Bronchopulmonary dysplasia (BPD) is a chronic lung disease of prematurity. Exposure to noxious stimuli such as hyperoxia, volutrauma, and infection in infancy can have long-reaching impacts on lung health and predispose towards the development of conditions such as chronic obstructive pulmonary disease (COPD) in adulthood. BPD and COPD are both marked by lung tissue degradation, neutrophil influx, and decreased lung function. Both diseases also express a change in microbial signature dominated by Proteobacteria abundance and Lactobacillus scarcity. However, the relationship between pulmonary microbial dysbiosis and the mechanisms of downstream disease development has yet to be elucidated. We hypothesized that a double-hit hyperoxia and LPS murine model of BPD would show heightened Ac-PGP pathway and neutrophil activity. Through gain- and loss-of-function studies in the same model we showed that Ac-PGP plays a critical role in driving BPD development. We tested a novel inhaled live biotherapeutic using active Lactobacillus strains to counteract lung dysbiosis in in vitro and in vivo models of BPD and COPD. The Lactobacillus LBP is effective in improving lung structure and function, reducing neutrophil influx, and reducing a broad swath of pro-inflammatory markers in these models of chronic pulmonary disease. Live inhaled microbiome-based therapeutics show promise in addressing common pathways of disease progression that in the future can be targeted in a variety of chronic lung diseases.

microbiology↗