Exposure to b-LED Light While Exerting Antimicrobial Activity on Gram-Negative and -Positive Bacteria Promotes Transient EMT-like Changes and Growth Arrest in Keratinocytes

Blue light promotes conjunctival epithelial-mesenchymal transition and collagen deposition through ITGB4

The increasing prevalence of LED technology heightened blue light (BL) exposure, raising concerns about its long-term effects on ocular health. This study investigated the transcriptomic response of conjunctiva to BL exposure, highlighting potential biomarkers for conjunctival injury. We exposed human conjunctival epithelial cells and C57BL/6 mice to BL to establish in vitro and in vivo models and identified the responsive genes in mice's conjunctiva to BL exposure by RNA sequencing transcriptome analysis. Western blotting, wound healing assays, transwell assay, and phalloidin staining assessed phenotypes of epithelial-mesenchymal transition (EMT). BL disrupted cell conjunction and regulated EMT-related proteins. RNA sequencing analysis revealed upregulation of ITGB4 and enrichment of cell migration and adhesion pathways. Reactive oxygen species-mediated damage caused by BL upregulated ITGB4 expression, promoting cell migration and EMT through the extracellular signal-regulated kinase /Snail pathway.

KDEON WK-11: A short antipseudomonal peptide with promising potential

The plight of antimicrobial resistance continues to limit the availability of antibiotic treatment effective in combating resistant bacterial infections. Despite efforts made to rectify this issue and minimise its effects on both patients and the wider community, progress in this area remains minimal. Here, we de-novo designed a peptide named KDEON WK-11, building on previous work establishing effective residues and structures active in distinguished antimicrobial peptides such as lactoferrin. We assessed its antimicrobial activity against an array of bacterial strains and identified its most potent effect, against Pseudomonas aeruginosa with an MIC value of 3.12 μM, lower than its counterparts developed with similar residues and chain lengths. We then determined its anti-biofilm properties, potential mechanism of action and in vitro cytotoxicity. We identified that KDEON WK-11 had a broad range of antimicrobial activity and specific capabilities to fight Pseudomonas aeruginosa with low in vitro cytotoxicity and promising potential to express anti-lipopolysaccharide qualities, which could be exploited to expand its properties into an anti-sepsis agent.