The link between ferroptosis and airway inflammatory diseases: A novel target for treatment.

Ferroptosis is an iron-dependent mode of cell death characterized by intracellular lipid peroxide accumulation and a redox reaction imbalance. Compared with other modes of cell death, ferroptosis has specific biological and morphological features. The iron-dependent lipid peroxidation accumulation is manifested explicitly in the abnormal metabolism of intracellular lipid oxides catalyzed by excessive iron ions with the production of many reactive oxygen species and over-oxidization of polyunsaturated fatty acids. Recent studies have shown that various diseases, which include intestinal diseases and cancer, are associated with ferroptosis, but few studies are related to airway inflammatory diseases. This review provides a comprehensive analysis of the primary damage mechanisms of ferroptosis and summarizes the relationship between ferroptosis and airway inflammatory diseases. In addition to common acute and chronic airway inflammatory diseases, we also focus on the progress of research on COVID-19 in relation to ferroptosis. New therapeutic approaches and current issues to be addressed in the treatment of inflammatory airway diseases using ferroptosis are further proposed.

Seven ferroptosis-specific expressed genes are considered as potential biomarkers for the diagnosis and treatment of cigarette smoke-induced chronic obstructive pulmonary disease.

Background: Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease characterized by incomplete reversible airway obstruction, with high mortality and disability rates, and smoking is the primary risk factor for COPD. Studies performed to date have confirmed that iron and ferroptosis play crucial roles in the development of cigarette smoke-induced COPD, but the exact mechanisms have not been fully elucidated. Methods: The microarray datasets GSE10006, GSE11784, and GSE20257 were downloaded from the Gene Expression Omnibus (GEO) database to identify differentially expressed genes (DEGs) between COPD smokers and non-smokers airway epithelial. Protein-protein interaction (PPI) and hub gene networks were constructed using the STRING database and Cytoscape software. At the same time, the 3 datasets were screened for ferroptosis-related genes that were co-differentially expressed. The ferroptosis-related hub genes (FRHGs) that overlapped with the ferroptosis-related genes and hub genes were then identified. Next, the mRNA-miRNA network was constructed, and Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis for target genes were performed. Finally, GSE19407, GSE994, and GSE27973 were used to evaluate the expression of hub genes. Results: We identified 7 potential FRHGs (NQO1, AKR1C3, AKR1C1, GPX2, TXNRD1, SRXN1, SLC7A11), which showed good diagnostic properties. The molecular functions (MFs) of FRHGs mainly influence biological processes (BPs) responding to oxidative stress. Nrf2 pathways may be the key pathways regulating ferroptosis in cigarette smoke-induced COPD. Meanwhile, co-expressed mRNAs and miRNAs were selected to construct mRNA-miRNA interaction networks. Furthermore, based on the 7 FRHGs mentioned above, we found that benzoic acid showed high drug targeting relevance. Conclusions: This work identified 7 FRHGs as potential biomarkers for the diagnosis and treatment of COPD and provided insights into the mechanisms of disease development in cigarette smoke-induced COPD at the transcriptome level.

Isorhamnetin Alleviates Airway Inflammation by Regulating the Nrf2/Keap1 Pathway in a Mouse Model of COPD.

Chronic obstructive pulmonary disease (COPD) is a severely disabling chronic lung disease characterized by persistent airway inflammation, which leads to limited expiratory airflow that deteriorates over time. Isorhamnetin (Iso) is one of the most important active components in the fruit of Hippophae rhamnoides L. and leaves of Ginkgo biloba L, which is widely used in many pulmonary disease studies because of its anti-inflammatory effects. Here, we investigated the pharmacological action of Iso in CS-induced airway inflammation and dissected the anti-inflammation mechanisms of Iso in COPD mice. A mouse model of COPD was established by exposure to cigarette smoke (CS) and intratracheal inhalation of lipopolysaccharide (LPS). Our results illustrated that Iso treatment significantly reduced leukocyte recruitment and excessive secretion of interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), and regulated upon activation, normal T-cell expressed and secreted (RANTES) in BALF of CS-induced COPD mice in a dose-dependent manner. This improved airway collagen deposition and emphysema, and further alleviated the decline in lung functions and systemic symptoms of hypoxia and weight loss. Additionally, Iso treatment obviously improves the T lymphocyte dysregualtion in peripheral blood of COPD mice. Mechanistically, Iso may degrade Keap1 through ubiquitination of p62, thereby activating the nuclear factor erythroid 2-related factor (Nrf2) pathway to increase the expression of protective factors, such as heme oxygenase-1 (HO-1), superoxide dismutase (SOD) 1, and SOD2, in lungs of CS-exposed mice, which plays an anti-inflammatory role in COPD. In conclusion, our study indicates that Iso significantly alleviates the inflammatory response in CS-induced COPD mice mainly by affecting the Nrf2/Keap1 pathway. More importantly, Iso exhibited anti-inflammatory effects comparable with Dex in COPD and we did not observe discernible side effects of Iso. The high safety profile of Iso may make it a potential drug candidate for COPD.

Clinical efficacy and adverse events of baricitinib treatment for coronavirus disease-2019 (COVID-19): A systematic review and meta-analysis.

The benefits of baricitinib in coronavirus disease-2019 are inadequately defined. We performed a systematic review and meta-analysis of studies of baricitinib to determine its clinical efficacy and adverse events in patients with COVID-19. Databases were searched from their inception to September 5, 2021. The primary outcome was the coefficient of mortality. We also compared secondary indicators and adverse events between baricitinib treatment and placebo or other treatments. Twelve studies of 3564 patients were included and assessed qualitatively (modified Jadad and Newcastle-Ottawa Scale scores). Baricitinib effectively improved the mortality rate (relative risk of mortality = 0.56; 95% confidence interval: 0.46-0.69; p < 0.001; I2 = 2%), and this result was unchanged by subgroup analysis. Baricitinib improved intensive care unit admission, the requirement for invasive mechanical ventilation, and improved the oxygenation index. Data from these studies also showed that baricitinib slightly reduced the risk of adverse events. Regarding the choice of the drug dosage of baricitinib, the high-dose group appeared to have additional benefits for clinical efficacy. Our study shows that baricitinib may be a promising, safe, and effective anti-severe acute respiratory syndrome-coronavirus-2 drug candidate, with the advantages of low cost, easy production, and convenient storage.

[Expression and activity of polymorphisms in the 67-kDa protein of the NADPH oxidase system]. / Expresión y actividad de posibles polimorfismos provenientes de individuos normales en la proteína de 67 kd del sistema NADPH oxidasa utilizando el sistema COSphox.

The NADPH oxidase system plays a central role in the antimicrobial activity of phagocytes. This system is initiated by the translocation of cytosolic proteins p67phox, p47phox and p40phox to be in close contact with membrane flavocytochrome b558. This event begins the electron transfer from cytosolic NADPH to molecular oxygen to produce superoxide anions. Herein, a functional analysis is presented of p67phox polymorphisms identified from healthy humans. Mutations were generated in the p67phox cDNA by site-directed mutagenesis and then transiently expressed in COS7 cells that also expressed gp91phox, p22phox, and p47phox from stable transgenes. The changes Va1166lle, Pro329Ser and His389Gln correspond to possible polymorphisms identified in healthy individuals revealed a functional activity similar to COSphox cells transiently transfected with WT p67phox; therefore, these modifications are not associated with genetic deficiencies in NADPH oxidase. In conclusion, the COSphox system represents an easily transfectable model for analysis of NADPH oxidase function in intact cells. The analysis of mutant derivatives of p67phox provides insight into molecular mechanisms by which this subunit regulates the NADPH oxidase.

Expresión y actividad de posibles polimorfismos provenientes de individuos normales en la proteína de 67 kd del sistema NADPH oxidasa utilizando el sistema COS phox / Expression and activity of polymorphisms in the 67-kDa protein of the NADPH oxidase system

El sistema NADPH oxidasa de las células fagocíticas cumple una función importante durante la respuesta antimicrobiana del organismo. La activación de este sistema está precedida por la translocación de las proteínas citosólicas p67 phox , p47 phox y p40 phox hacia la membrana para ponerse en contacto con el flavocitocromo b 558 , lo que induce la generación del anión superóxido, un precursor de agentes microbicidas oxidantes. El presente trabajo presenta un análisis funcional del sistema NADPH oxidasa basado en los hallazgos de polimorfismos encontrados en el gen de p67 phox de individuos sanos. Para esto se generaron mutaciones en el cADN que codifica la p67 phox y se expresaron en el sistema de células COS phox . Los datos obtenidos en el presente trabajo indican que los cambios Val 166 .Ile, Pro 329 .Ser y His 389 .Gln no generan alteraciones en el funcionamiento de la p67 phox cuando su función se analizó en el sistema transgénico basado en células COS-7. Por lo tanto, estos polimorfismos no generan ningún riesgo genético de producir deficiencias en la activación del sistema NADPH oxidasa. Además, se demuestra que el modelo de células COS phox representa un nuevo sistema celular, fácilmente transfectable que permite estudiar la función del sistema NADPH oxidasa de las células fagocíticas y sus particularidades genéticas. Finalmente, los hallazgos con estos polimorfismos nos permiten avanzar en el conocimiento sobre los mecanismos moleculares involucrados en la activación del sistema NADPH oxidasa células fagocíticas