Aurintricarboxylic acid mitigates cigarette smoke extract induced oxidative stress and pulmonary inflammation via inhibition of NF-ҡB/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-ҡB/p65 activation and nuclear translocation. ATA efficaciously diminished the oxidative stress and pulmonary inflammation associated with lung pathogenesis through TNF-α/TNFR1/NF-ҡB/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-ҡB/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-ҡB/p65 signaling pathway.

Paradoxical effects of aurintricarboxylic acid and RG-13577: acute thrombosis and in-stent stenosis in a passive-coated stent

PURPOSE

To investigate if a platelet inhibitor (aurintricarboxylic acid [ATA]) and a heparin-mimicking antagonist (RG-13577) of basic fibroblast growth factor 2 (bFGF2) could be combined as a stable compound and attached to conventional bare metal stents to hinder thrombus formation and inflammatory reactions of stenting.

METHODS

Fifteen domestic pigs were stented with RG-13577/ATA-coated (n=6), ATA-coated (n=12), and bare metal stents (n=12) in the left anterior descending (LAD) and left circumflex (LCX) coronary arteries. All surviving pigs were evaluated with contrast angiography and intravascular ultrasonography (IVUS) after 4 weeks. Histological analysis of the stented arteries was performed after hematoxylin-eosin staining. Tissue factor (TF) staining and scanning electron microscopy (SEM) were performed in animals with acute stent thrombosis.

RESULTS

Five of the 6 animals receiving an RG-13577/ATA-coated stent experienced acute stent thrombosis, while no adverse events occurred in the animals of the other 2 groups. Follow-up angiography did not show significant in-stent stenosis in either bare or ATA-coated stents. However, histomorphometry revealed larger neointimal area (3.54+/-0.69 mm2 versus 1.82+/-0.27 mm2, p<0.05) and outward plaque area (1.56+/-0.34 mm2 versus 0.61+/-0.12 mm2, p<0.05) in ATA-coated stents. Three-dimensional IVUS analysis showed analogous results, with significantly larger neointimal volume and outward plaque volume in ATA-coated stents. There was a slight increase in TF staining around the stent struts, while SEM showed increased platelet adhesion and activity in RG-13577/ATA-coated stents versus the ATA-coated and bare metal stents.

CONCLUSION

RG-13577/ATA-coated stents lead to acute stent thrombosis. The ATA coating alone did not lead to acute events, but resulted in higher neointimal hyperplasia and expansive remodeling. These results underline the importance of preclinical studies before using new coated stents in human arteries.

IL3-dependent cells die by apoptosis on removal of their growth factor

The IL3-dependent cell line FDCP-2 dies within 32 h of removal of IL3. Electron microscope studies indicate that 22 h after IL3 removal the nuclei are condensed, but the morphology of mitochondria and ribosomes is preserved. This pattern is characteristic of apoptosis. IL3 removal also results in the fragmentation of DNA into nucleosome-sized pieces, suggesting that an endonuclease is activated. The protein synthesis inhibitor, cycloheximide, enhances survival on IL3 removal, suggesting that death is an active process. The nuclease inhibitor, aurintricarboxylic acid, also enhances survival, suggesting a causal role for DNA fragmentation in apoptosis.

Aurintricarboxylic acid and Evans Blue represent two different classes of anionic compounds which selectively inhibit the cytopathogenicity of human T-cell lymphotropic virus type III/lymphadenopathy-associated virus

Aurintricarboxylic acid, an anionic triphenylmethane dye, and Evans Blue, an anionic compound structurally related to suramin, are, like suramin itself, inhibitors of human T-cell lymphotropic virus type III (HTLV-III)/-lymphadenopathy-associated virus (LAV) in vitro. These compounds may be targeted, at least in part, at the HTLV-III/LAV reverse transcriptase. The lack of any appreciable cytostatic action of aurintricarboxylic acid, Evans Blue and suramin against several murine and human cell lines, their inability to inhibit cellular DNA, RNA and protein synthesis, and their high lethal dose-50 (greater than or equal to 0.340 g/kg) for NMRI mice point to the selectivity of the compounds as inhibitors of HTLV-III/LAV.