ABSTRACT
Corneal alkali burns often occur in industrial production and daily life, combined with infection, and may cause severe eye disease. Oxidative stress and neovascularization (NV) are important factors leading to a poor prognosis. URP20 is an antimicrobial peptide that has been proven to treat bacterial keratitis in rats through antibacterial and anti-NV effects. Therefore, in this study, the protective effect and influence mechanism of URP20 were explored in a rat model of alkali burn together with pathogenic bacteria (Staphylococcus aureus and Escherichia coli) infection. In addition, human umbilical vein endothelial cells (HUVECs) and human corneal epithelial cells (HCECs) were selected to verify the effects of URP20 on vascularization and oxidative stress. The results showed that URP20 treatment could protect corneal tissue, reduce corneal turbidity, and reduce the NV pathological score. Furthermore, URP20 significantly inhibited the expression of the vascularization marker proteins VEGFR2 and CD31. URP20 also reduced the migration ability of HUVECs. In terms of oxidative stress, URP20 significantly upregulated SOD and GSH contents in corneal tissue and HCECs (treated with 200 µM H2O2) and promoted the expression of the antioxidant protein Nrf2/HO-1. At the same time, MDA and ROS levels were also inhibited. In conclusion, URP20 could improve corneal injury combined with bacterial infection in rats caused by alkali burns through antibacterial, anti-NV, and antioxidant activities.
Subject(s)
Bacterial Infections , Burns, Chemical , Corneal Injuries , Corneal Neovascularization , Eye Burns , Rats , Humans , Animals , Burns, Chemical/complications , Burns, Chemical/drug therapy , Burns, Chemical/metabolism , Corneal Neovascularization/metabolism , Antioxidants/pharmacology , Antioxidants/therapeutic use , Hydrogen Peroxide/pharmacology , Neovascularization, Pathologic/metabolism , Corneal Injuries/drug therapy , Human Umbilical Vein Endothelial Cells , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/pharmacology , Eye Burns/chemically induced , Eye Burns/drug therapy , Eye Burns/pathology , Disease Models, Animal , Alkalies/toxicityABSTRACT
OBJECTIVE: To investigate the effects of serine protease inhibitor 3n (SerpinA3n) in a neonatal mouse model of asthma. METHODS: The study utilized a neonatal mouse ovalbumin (OVA) sensitization model of asthma. Wild type (WT) and SerpinA3n-/- mice were randomly divided into WT/SerpinA3n-/- + saline, WT/SerpinA3n-/- + OVA, WT/SerpinA3n-/- + OVA + rSerpinA3n (recombinant mouse SerpinA3n protein), and WT/SerpinA3n-/- + OVA + DEX (dexamethasone, positive control) groups followed by hematoxylin-eosin (HE) staining, Masson's trichrome stainings, Sircol soluble collagen assay, quantitative real time polymerase chain reaction (qRT-PCR), Western Blot and enzyme linked immunosorbent assay (ELISA). RESULTS: OVA-induced neonatal mice showed the increases in airway hyper-reactivity with the up-regulated total cells, eosinophil, lymphocyte and neutrophil in bronchoalveolar lavage fluid (BALF), which was much higher in WT + OVA + rSerpinA3n group (P < 0.05). SerpinA3n-/- suppressed the serum concentrations of total immunoglobulin E (IgE) and OVA-specific IgG1 in OVA-induced asthmatic mice, and alleviated the pathological changes of lung tissues, which was reversed by rSerpinA3n injection (P < 0.05). Besides, WT + OVA group showed more severe in collagen deposition in lung tissues than SerpinA3n-/- + OVA group with increased expression of matrix metallopeptidase-2 (MMP-2), MMP-9, Eotaxin-1, Interleukin 5 (IL-5), IL-13 and IL-4 in lung tissues and deceased IL-10 and Interferon-gamma (IFN-γ) (P < 0.05). Nevertheless, the ameliorating effects of SerpinA3n knockout on OVA-induced asthmatic mice can be reversed by rSerpinA3n. CONCLUSION: SerpinA3n knockout can attenuate airway hyper-reactivity, mitigate inflammatory responses and reduce collagen deposition in lung tissues of neonatal mice with asthma.