Imbalance of gut microbiota is involved in the development of chronic obstructive pulmonary disease: A review

The cross-talk between the metabolome and microbiome in a double-hit neonatal rat model of bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD), a chronic lung disease in preterm infants, is associated with inflammation and high oxygen exposure. However, the effects of antenatal inflammation and postnatal extended hyperoxia on the metabolome and microbiome remain unclear. In this study, pregnant rats received lipopolysaccharide or saline injections on gestational day 20 and were exposed to either 21 % or 80 % oxygen for 4 weeks post-birth. Analysis revealed an increase in Firmicutes, Proteobacteria, and Actinobacteria, with a decrease in Bacteroidetes in BPD rats. Metabolomic analysis identified 78 altered metabolites, primarily lipids, enriched in pathways including arginine biosynthesis, sphingolipid metabolism, and primary bile acid biosynthesis in BPD rats. Integration analysis revealed strong correlations between intestinal microbiota and metabolites in BPD rats. These findings underscored the impact of antenatal inflammation and prolonged postnatal hyperoxia on gut microbiota and serum metabolome, suggesting their role in BPD pathogenesis.

Mechanisms underlying Th2-dominant pneumonia caused by plastic pollution derivatives (PPD): A molecular toxicology investigation that encompasses gut microbiomics and lung metabolomics

An investigation was conducted by researchers on how dibutyl phthalate (DBP) and polystyrene microplastics (PS-MP) influence the development of pneumonia using a mouse model. For a duration of five weeks, the mice were subjected to exposure of DBP (30 mg/kg/day) and PS-MP (0.1 mg/day). The findings indicated notable pathological alterations in airway tissues, increased oxidative stress levels, and intensified inflammation, thereby establishing a connection between plastic pollution and pneumonia. Further examination indicated the involvement of ferroptosis and oxidative stress in the progression of the disease. Administration of deferoxamine (DFO) (100 mg/kg) resulted in symptom relief and reduced pathological alterations, as validated by metabolomic investigations. Increased levels of reactive oxygen species (ROS) triggered a Th2-mediated eosinophilic inflammatory response, marked by elevated IL-4 and reduced IFN-γ via the NFκB pathway. Moreover, analyses of the gut microbiome and metabolomics demonstrated that PPD modifies microbial populations and pulmonary metabolism, linking its effects on pneumonia through the gut-lung axis. This research highlights the health hazards associated with plastic pollution and proposes a framework for tackling these issues.

The beneficial effects of Akkermansia muciniphila and its derivatives on pulmonary fibrosis

Pulmonary fibrosis (PF) is a progressive and debilitating respiratory condition characterized by excessive deposition of extracellular matrix proteins and scarring within the lung parenchyma. Despite extensive research, the pathogenesis of PF remains incompletely understood, and effective therapeutic options are limited. Emerging evidence suggests a potential link between gut microbiota dysbiosis and the development of PF, highlighting the gut-lung axis as a promising therapeutic target. Akkermansia muciniphila (A. muciniphila), a mucin-degrading bacterium residing in the gut mucosal layer, has garnered considerable interest due to its immunomodulatory and anti-inflammatory properties. This study investigates the therapeutic potential of live and pasteurized A. muciniphila, as well as its extracellular vesicles (EVs), in mitigating inflammation and fibrosis in a murine model of carbon tetrachloride (CCl4)-induced PF exacerbated by a high-fat diet (HFD). Male C57BL/6 mice were divided into groups receiving either a normal diet or an HFD, with or without CCl4 administration. The mice were then treated with live or pasteurized A. muciniphila, or its EVs. Lung tissue was analyzed for the expression of inflammatory markers and fibrosis markers using real-time PCR and ELISA. Administration of live and pasteurized A. muciniphila, as well as its EVs, significantly downregulated the expression of inflammatory and fibrosis markers in the lung tissue of CCl4-induced PF mice. Furthermore, these treatments ameliorated the increased production of IL-6 and reduced IL-10 levels observed in the HFD and CCl4-treated groups. These findings suggest that A. muciniphila and its derivatives exert protective effects against pulmonary inflammation and fibrosis, potentially through modulation of the gut-lung axis. The study highlights the therapeutic potential of A. muciniphila and its derivatives as novel interventions for the management of PF, warranting further preclinical and clinical investigations.

Air pollution, dysbiosis and diseases: pneumonia, asthma, COPD, lung cancer and irritable bowel syndrome

With substantial effects on human health, air pollution has become a major global concern. Air pollution has been linked to numerous gastrointestinal and respiratory diseases with increasing mortalities. The gut and respiratory dysbiosis brought about by air pollution has recently received much attention. This review attempts to provide an overview of the types of air pollutants, their sources, their impact on the respiratory and gut dysbiotic patterns and their correlation with five major diseases including pneumonia, asthma, COPD, lung cancer and irritable bowel syndrome. Deeper insights into the links between pollutants, dysbiosis and disease may pave the way for novel diagnostic biomarkers for prognosis and early detection of these diseases, as well as ways to ease the disease burden.

Identification of diagnostic biomarkers and immune cell profiles associated with COPD integrated bioinformatics and machine learning

This retrospective transcriptomic study leveraged bioinformatics and machine learning algorithms to identify novel gene biomarkers and explore immune cell infiltration profiles associated with chronic obstructive pulmonary disease (COPD). Utilizing an integrated analysis of metadata encompassing six gene expression omnibus (GEO) microarray datasets, 987 differentially expressed genes were identified. Further gene ontology and pathway enrichment analyses revealed the enrichment of these genes across various biological processes and pathways. Moreover, a systematic integration of two machine learning algorithms along with pathway-gene correlations identified six candidate biomarkers, which were validated in a separate cohort comprising six additional microarray datasets, ultimately identifying ADD3 and GNAS as diagnostic biomarkers for COPD. Subsequently, the diagnostic efficacy of ADD3 and GNAS was assessed, and the impact of their expression levels on overall survival was further evaluated and quantified in the validation cohort. Examination of immune cell subtype infiltration found increased proportions of cytotoxic CD8+ T cells, resting and activated NK cells, along with decreased M0 and M2 macrophages, in COPD versus control samples. Correlation analyses also uncovered significant associations between ADD3 and GNAS expression and infiltration of various immune cell types. In conclusion, this study elucidates crucial COPD diagnostic biomarkers and immune cell profiles which may illuminate the immunopathological drivers of COPD progression, representing personalized therapeutic targets warranting further investigation.

Gut Microbiota Modulation in the Management of Chronic Obstructive Pulmonary Disease: A Literature Review

Chronic obstructive pulmonary disease (COPD) represents a significant global health burden, characterized by progressive airflow limitation and exacerbations that significantly impact patient morbidity and mortality. Recent research has investigated the interplay between the gut and the lungs, known as the gut-lung axis, highlighting the role of the gut microbiome in COPD pathogenesis. Dysbiosis, characterized by microbial imbalance, has implications for COPD, influencing disease progression and susceptibility to exacerbations. This comprehensive review integrates current scientific literature on gut microbiota modulation as a therapeutic avenue for COPD management. Through a thorough discussion of studies investigating probiotics, prebiotics, synbiotics, antibiotics, dietary fiber, and fecal microbiota transplantation, this review summarizes the influence of these interventions on COPD via the gut-lung axis through the modulation of systemic inflammation, mucosal immunity, and metabolic processes. The interventions highlighted here show potential in preventing COPD exacerbations, preserving lung function, and improving patient quality of life. By compiling the latest scientific evidence, this review provides a comprehensive framework for physicians and researchers to deduce the effectiveness of gut microbiome modulation as an adjunctive therapeutic strategy in COPD management.

Causal relationship between gut microbiota and idiopathic pulmonary fibrosis: A two-sample Mendelian randomization

To explore the causal relationship between gut microbiota (GM) and Idiopathic pulmonary fibrosis (IPF), we performed a two-sample Mendelian randomization (MR). GM was used as an exposure factor, and instrumental variables were determined from the GWAS of 18,340 participants. GWAS of IPF (including 1028 IPF patients and 196,986 controls) from the FinnGen was used as the outcome factor. The primary analysis method is the inverse variance weighted (IVW) method, and sensitivity analysis was used to validate the reliability. Family Bacteroidaceae (OR = 1.917 95% CI = 1.083-3.393, P = .026), order Gastranaerophilales (OR = 1.441 95% CI = 1.019-2.036, P = .039), genus Senegalimassilia (OR = 2.28 95% CI = 1.174-4.427, P = .015), phylum Cyanobacteria (OR = 1.631 95% CI = 1.035-2.571, P = .035) were positively correlated with IPF. FamilyXIII(OR = 0.452 95% CI = 0.249-0.82, P = .009), order Selenomonadale (OR = 0.563 95% CI = 0.337-0.941, P = .029), genus Veillonella (OR = 0.546 95% CI = 0.304-0.982, P = .043) (OR = 0.717 95% CI = 0.527-0.976, P = .034), genus Ruminococcusgnavus (OR = 0.717 95% CI = 0.527-0.976, P = .034), genus Oscillibacter (OR = 0.571 95% CI = 0.405-0.806, P = .001) was negatively correlated with IPF. Sensitivity analysis showed no evidence of pleiotropy or heterogeneity (P > .05). The results of MR demonstrated a causal relationship between GM and IPF. Further studies are needed to investigate the intrinsic mechanisms of the GM in the pathogenesis of IPF.

A metabolomics perspective on the effect of environmental micro and nanoplastics on living organisms: A review

The increasing trend regarding the use of plastics has arisen an exponential concern on the fate of their derived products to the environment. Among these derivatives, microplastics and nanoplastics (MNPs) have been featured for their associated environmental impact due to their low molecular size and high surface area, which has prompted their ubiquitous transference among all environmental interfaces. Due to the heterogenous chemical composition of MNPs, the study of these particles has focused a high number of studies, as a result of the myriad of associated physicochemical properties that contribute to the co-transference of a wide range of contaminants, thus becoming a major challenge for the scientific community. In this sense, both primary and secondary MNPs are well-known to be adscribed to industrial and urbanized areas, from which they are massively released to the environment through a multiscale level, involving the atmosphere, hydrosphere, and lithosphere. Consequently, much research has been conducted on the understanding of the interconnection between those interfaces, that motivate the spread of these contaminants to biological systems, being mostly represented by the biosphere, especially phytosphere and, finally, the anthroposphere. These findings have highlighted the potential hazardous risk for human health through different mechanisms from the environment, requiring a much deeper approach to define the real risk of MNPs exposure. As a result, there is a gap of knowledge regarding the environmental impact of MNPs from a high-throughput perspective. In this review, a metabolomics-based overview on the impact of MNPs to all environmental interfaces was proposed, considering this technology a highly valuable tool to decipher the real impact of MNPs on biological systems, thus opening a novel perspective on the study of these contaminants.

Therapeutic Effects of Lifei Decoction in a Murine Model of COPD Induced by LPS and Cigarette Smoke

Introduction

The Lifei Decoction (LD) is a commonly utilized Chinese medicine for the treatment of sepsis and bronchial inflammation. However, its therapeutic potential in chronic obstructive pulmonary disease (COPD) remains unknown. Therefore, the objective of this study was to investigate the therapeutic efficacy and underlying mechanism of LD in a mouse model of COPD induced by cigarette smoke (CS) combined with lipopolysaccharide (LPS).

Methods

Hematoxylin-eosin (H&E) staining was employed to observe the pathological alterations in lung tissue, while ELISA was utilized for the detection of levels of inflammatory factors in both lung tissue and bronchoalveolar lavage fluid (BALF). Additionally, Western blot analysis was conducted to assess the expression of p-NF-κB, GDF11, ZO-1, and Occludin-1 proteins. The changes in intestinal flora were evaluated using the viable bacteria count method.

Results

The administration of LD demonstrates significant efficacy in mitigating pulmonary tissue damage in a murine model, while concurrently inhibiting the activation of the inflammatory pathway NF-κB to attenuate the levels of pro-inflammatory factors. Moreover, LD exhibits the capacity to enhance the expression of intestinal functional proteins ZO-1 and Occludin-1, thereby rectifying dysbiosis within the gut microbiota.

Conclusion

The LD shows great promise as a potential treatment for COPD.

The role and mechanism of gut-lung axis mediated bidirectional communication in the occurrence and development of chronic obstructive pulmonary disease

The current studies have shown that the occurrence and development of chronic obstructive pulmonary disease (COPD) are closely related to the changes in gut health and its microenvironment, and even some gut diseases have significant clinical correlation with COPD. The dysbiosis of gut microbiota observed in COPD patients also suggests a potential bidirectional interaction between the gut and lung. Communication between the gut and lung may occur through circulating inflammatory cells, gut microbial metabolites, and circulating inflammatory mediators, but the mechanism of bidirectional communication between the gut and lung in COPD is still under study. Therefore, more research is still needed in this area. In this review, we summarize recent clinical studies and animal models on the role of the gut-lung axis in the occurrence and development of COPD and its mechanisms, so as to provide ideas for further research in this field. In addition, we also summarized the negative effects of COPD medication on gut microbiota and the gut microbiota risk factors for COPD and proposed the potential prevention and treatment strategies.

The impact of aging-induced gut microbiome dysbiosis on dendritic cells and lung diseases

Aging is an inevitable natural process that impacts every individual, and understanding its effect on the gut microbiome and dendritic cell (DC) functionality in elderly subjects is crucial. DCs are vital antigen-presenting cells (APCs) that orchestrate the immune response, maintaining immune tolerance to self-antigens and bridging innate and adaptive immunity. With aging, there is a shift toward nonspecific innate immunity, resulting in a decline in adaptive immune responses. This alteration raises significant concerns about managing the health of an elderly population. However, the precise impact of aging and microbiome changes on DC function and their implications in lung-associated diseases remain relatively understudied. To illuminate this subject, we will discuss recent advancements in understanding the connections between aging, gut dysbiosis, DCs, and lung diseases. Emphasizing the key concepts linking age-related gut microbiome changes and DC functions, we will focus on their relevance to overall health and immune response in elderly individuals. This article aims to improve our understanding of the intricate relationship between aging, gut microbiome, and DCs, potentially benefiting the management of age-associated diseases and promoting healthy aging.