Gut-Lung Microbiota Interaction in COPD Patients: A Literature Review

Probiotics combined with Budesonide and Ipratropium bromide for chronic obstructive pulmonary disease: A retrospective analysis

To explore the effect of probiotics combined with budesonide and ipratropium bromide in the treatment of chronic obstructive pulmonary disease (COPD) on lung function and gut microbiota. This was a retrospective study of prospectively collected clinical data of 118 patients with COPD admitted to our hospital between January 2020 and December 2022. According to the treatment records, 59 patients received budesonide and irpratropium bromide (control group), and 59 patients received probiotics combined with budesonide and irpratropium bromide (observation group). The lung function, inflammatory factor levels, airway remodeling, and gut microbiota before and after treatment were compared between the 2 groups. After treatment, FVC, MMEF, PEF, and FEV1 in the 2 groups were higher than before treatment, and the values in the observation group were higher than those in the control group (P < .05). After treatment, the serum levels of TNF-α, IL-6, and PCT in the 2 groups were lower than before treatment, and the levels in the observation group were lower than those in the control group (P < .05). After treatment, the levels of serum MMP-9, VEGF, basic fibroblast growth factor, and NGF in the 2 groups were lower than before treatment, and the levels in the observation group were lower than those in the control group (P < .05). After treatment, the levels of lactobacilli and bifidobacteria in the 2 groups increased compared to those before treatment, and the observation group had a higher level, while the levels of Enterobacteriaceae and Enterococcus were lower in the observation group than those before treatment (P < .05). Based on budesonide and irpratropium bromide, probiotic treatment of COPD is more conducive to reducing the degree of inflammatory reactions, inhibiting airway remodeling, regulating the level of gut microbiota, and promoting the recovery of lung function.

NLRP6 controls pulmonary inflammation from cigarette smoke in a gut microbiota-dependent manner

Chronic obstructive pulmonary disease (COPD) is a major health issue primarily caused by cigarette smoke (CS) and characterized by breathlessness and repeated airway inflammation. NLRP6 is a cytosolic innate receptor controlling intestinal inflammation and orchestrating the colonic host-microbial interface. However, its roles in the lungs remain largely unexplored. Using CS exposure models, our data show that airway inflammation is strongly impaired in Nlrp6-deficient mice with drastically fewer recruited neutrophils, a key cell subset in inflammation and COPD. We found that NLRP6 expression in lung epithelial cells is important to control airway and lung tissue inflammation in an inflammasome-dependent manner. Since gut-derived metabolites regulate NLRP6 inflammasome activation in intestinal epithelial cells, we investigated the link between NLRP6, CS-driven lung inflammation, and gut microbiota composition. We report that acute CS exposure alters gut microbiota in both wild-type (WT) and Nlrp6-deficient mice and that antibiotic treatment decreases CS-induced lung inflammation. In addition, gut microbiota transfer from dysbiotic Nlrp6-deficient mice to WT mice decreased airway lung inflammation in WT mice, highlighting an NLRP6-dependent gut-to-lung axis controlling pulmonary inflammation.

Gut microbiota and chronic obstructive pulmonary disease: a Mendelian randomization study

Background

A growing number of studies implies a strong association between gut microbiota and chronic obstructive pulmonary disease (COPD). However, the causal impact between gut microbiota and COPD remains unclear. As a result, we used a two-sample Mendelian randomization (MR) method to investigate the connection between gut microbiota and COPD in this study.

Methods

The largest available genome-wide association study (GWAS) of gut microbiota was obtained from the MiBioGen consortium. Summary-level dataset for COPD were obtained from the FinnGen consortium. The main analysis method for determining the causal link between gut microbiota and COPD was inverse variance weighted (IVW). Subsequently, pleiotropy and heterogeneity tests were performed to determine the reliability of the results.

Results

IVW method identified 9 bacterial taxa nominally associated with the risk of COPD. Class Actinobacteria (p = 0.020), genus Allisonella (p = 0.024), genus Coprococcus2 (p = 0.002) and genus Oscillospira (p = 0.018) were protective against COPD. In addition, order Desulfovibrionales (p = 0.011), family Desulfovibrionaceae (p = 0.039), family Peptococcaceae (p = 0.020), family Victivallaceae (p = 0.012) and genus Marvinbryantia (p = 0.017) were associated with a higher risk of COPD. No pleiotropy or heterogeneity were found.

Conclusion

According to the findings of this MR analysis, a causal relationship exists between certain gut microbiota and COPD. New insights into the mechanisms of COPD mediated by gut microbiota are provided.