Regeneration capability of neonatal lung-derived decellularized extracellular matrix in an emphysema model.

Impaired and limited alveolar regeneration upon injury advances pulmonary disorders and irreversibly affects millions of people worldwide. Adult mammals do not have a strong potential to regenerate functional lung tissues, while neonatal lungs robustly proliferate and regenerate the functional tissue within a week of birth upon injury. The differential composition of the extracellular matrix (ECM) of neonatal tissues favors cellular proliferation and migration, fostering lung regeneration. Regardless, conventional ECM therapies employ adult-derived tissues. Therefore, the potential differences in regenerative properties of adult and neonatal lung ECM were investigated using in vitro and in vivo lung emphysema model. Decellularization of the neonatal and adult lungs was performed using freeze-thaw cycle method. Decellularization process was structurally characterized using SEM and immunostaining. In vitro treatment of neonatal lung-derived ECM (NECM) significantly enhanced the cellular migration and proliferation compared to adult-lung derived ECM (AECM) treated cigarette smoke-extract (CSE)-stimulated A549 cells. Following the administration of AECM and NECM, we observed a significant decline in emphysematous features and an improvement in lung functions in NECM group. NECM treatment increased the ratio of HOPX+/SpC+ cells with an active proliferation in SpC+ cells shown by colocalization of SpC+/Ki67+ and SpC+/Brdu+ cells. Moreover, NECM treatment activated the Neureguline-1/Erbb2 signaling and fostered a regenerative environment by upregulating the expression of regenerative genes including FGF, WNTs and AXIN-2 as compared to AECM treatment. Our findings suggested the potential utilization of NECM as novel therapeutics in regenerative medicine, deviating from the conventional application of adult-derived ECM treatments in pre-clinical and clinical research.

Aurintricarboxylic acid mitigates cigarette smoke extract induced oxidative stress and pulmonary inflammation via inhibition of NF-Ò¡B/p65 signaling.

Cigarette smoke (CS) induced emphysema and chronic pulmonary inflammation are major comorbidities of chronic obstructive pulmonary disease (COPD), a major cause of morbidity and mortality worldwide. CS exposure exacerbates pulmonary inflammation and compromises immunity to various infections. Aurintricarboxylic acid (ATA) is a polyanionic aromatic compound especially recognized for its anti-inflammatory, nucleic acid, and protein interaction inhibition properties. The study was designed to investigate the anti-inflammatory role of ATA against cigarette smoke extract (CSE) induced pulmonary inflammation. Nicotine concentration was quantified in CSE by UPLC/MS technique. In vitro, fluorescence microscopy, and flow cytometry was performed in CSE stimulated alveolar epithelial cells to determine the effect of ATA on oxidative stress-mediated cellular apoptosis. In vivo, pulmonary inflammation was induced in male Wistar rats via a modified non-invasive intratracheal instillation of cigarette smoke extract (100 µl/animal) twice a week for 8 weeks and post-treated with ATA (10 mg/kg) intraperitoneally for 15 days. Lung homogenates were assessed for MDA and GSH. Lung tissues were subjected to western blotting and histopathological analysis. As result, ATA reduced CSE-induced chromatin condensation, fragmentation, cellular apoptosis in alveolar epithelial cells, and apoptotic biomarkers expression including BAX and Caspase-3 in the lungs. ATA reduced inflammation by normalizing redox balance reflected by MDA/GSH levels. ATA obviated airspace enlargement, fiber deposition, and immune cell infiltration. Reduced inflammation was accompanied by inhibition of inflammatory biomarkers TNF-α, TNFR1, TWEAK, and NF-Ò¡B/p65 activation and nuclear translocation. ATA efficaciously diminished the oxidative stress and pulmonary inflammation associated with lung pathogenesis through TNF-α/TNFR1/NF-Ò¡B/p65 signaling pathway. HIGHLIGHTSATA treatment attenuates CSE-stimulated chromatin condensation, fragmentation, and cellular apoptosis in alveolar epithelial cells.ATA treatment inhibits CSE stimulated activation and nuclear translocation of NF-Ò¡B/p65.ATA treatment diminishes CSE-induced oxidant injury, apoptosis, and emphysema-like phenotypic changes in the lungs.ATA inhibits lung inflammation via suppression of the NF-Ò¡B/p65 signaling pathway.

Cigarette smoke extract triggers neoplastic change in lungs and impairs locomotor activity through wnt3a-ß-catenin signaling in aged COPD rodent model.

BACKGROUND: Chronic cigarette smoking primes immense decline in lung functions and retardation of motor functions with increase in age. This raise the question of whether age status overwhelm the susceptibility to smoking induced lung inflammatory diseases and neuro-motor dysfunctions. METHODS: To study the hypothesis 11-12 month old aged wistar rats (n = 6) were administered cigarette smoke extract (CSE) through intraperitoneal route (0.5 ml/rat) twice a week for 2 months. Respiratory lung functions were measured through whole body plethysmography. Lung histopathological evaluation and neuronal degeneration were observed by using H&E, picrosirius red and nissl staining respectively. Motor function tests were done through panel of neuro-behavioral tests and protein expressions were performed in lung and brain tissue homogenates through western blotting. RESULTS: Sub-chronic CSE exposure worsened the lung functions including decreased tidal volume (p < 0.05), peak inspiratory flow (p < 0.05) and enhanced pause (p < 0.05). Grossly, solid neoplastic lesions were visible on the supra-lateral surface of the lungs of the CSE treated animals. Histopathological examination revealed immune cell infiltration, dominated with macrophages and alveolar type II cells stained positive for PCNA. Increased expression of BAX, PCNA, Wnt-3a, p-ß-catenin (p < 0.05) was seen in the lungs of CSE treated aged animals. Elevated expression of inflammatory markers including NF-ϏB, TNF-α, TNF-R1, p-AKT was found in CSE treated lung tissues. Moreover, our result showed increased MCP-1, VEGF and IL-6 levels in BALF and plasma (p < 0.01) which might lead to neo-vascularization and excessive cell proliferation in lungs of CSE induced rats. Sub-chronic cigarette smoke exposure retarded the motor activity with suppression of D1 and D2 receptor expression in brain tissues. Brain tissue revealed the abundance of hyperchromatic and pyknotic nuclei suggesting neuronal degeneration. CONCLUSION: So in conclusion, chronic cigarette smoking in old age creates susceptibility to fast onset of lung inflammatory diseases and neuro-motor retardation than their nonsmoker counterparts.