Ciliogenesis is intrinsically altered in COPD small airways

Using Zebrafish to Study Multiciliated Cell Development and Disease States

Multiciliated cells (MCCs) serve many important functions, including fluid propulsion and chemo- and mechanosensing. Diseases ranging from rare conditions to the recent COVID-19 global health pandemic have been linked to MCC defects. In recent years, the zebrafish has emerged as a model to investigate the biology of MCCs. Here, we review the major events in MCC formation including centriole biogenesis and basal body docking. Then, we discuss studies on the role of MCCs in diseases of the brain, respiratory, kidney and reproductive systems, as well as recent findings about the link between MCCs and SARS-CoV-2. Next, we explore why the zebrafish is a useful model to study MCCs and provide a comprehensive overview of previous studies of genetic components essential for MCC development and motility across three major tissues in the zebrafish: the pronephros, brain ependymal cells and nasal placode. Taken together, here we provide a cohesive summary of MCC research using the zebrafish and its future potential for expanding our understanding of MCC-related disease states.

Association Between Urinary Phthalate Metabolites and Chronic Obstructive Pulmonary Disease: A Cross-Sectional Study

Objective

To determine the association of urinary phthalate metabolites with chronic obstructive pulmonary disease (COPD), airflow obstruction, lung function and respiratory symptoms.

Methods

Our study included a total of 2023 individuals aged ≥ 40 years old in the National Health and Nutrition Examination Survey (NHANES). Multivariate logistic regression was conducted to explore the correlation of eleven urinary phthalate metabolites (MCNP, MCOP, MECPP, MnBP, MCPP, MEP, MEHHP, MEHP, MiBP, MEOHP, and MBzP) with COPD, airflow obstruction and respiratory symptoms. Linear regression analyses were used to evaluate the relationship between urinary phthalate metabolites and lung function.

Results

When compared to the first tertile, the third tertile of MEHHP was associated with the risk of COPD [OR: 2.779; 95% confidence interval (CI): 1.129-6.840; P = 0.026]. Stratified analysis showed that MEHHP increased the risk of COPD by 7.080 times in male participants. Both MCPP and MBzP were positively correlated with the risk of airflow obstruction. The third tertile of MBzP increased the risk of cough by 1.545 (95% CI: 1.030-2.317; P = 0.035) times. Both FEV1 and FVC were negatively associated with MEHHP, MECPP, MnBP, MEP, MiBP and MEOHP.

Conclusion

Higher levels of MEHHP are associated with increased risk of COPD, and lower measures of FEV1 and FVC. MBzP is positively related to airflow obstruction and cough.

Airway ciliated cells in adult lung homeostasis and COPD

Cilia are organelles emanating from the cell surface, consisting of an axoneme of microtubules that extends from a basal body derived from the centrioles. They are either isolated and nonmotile (primary cilia), or grouped and motile (motile cilia). Cilia are at the centre of fundamental sensory processes and are involved in a wide range of human disorders. Pulmonary cilia include motile cilia lining the epithelial cells of the conductive airways to orchestrate mucociliary clearance, and primary cilia found on nondifferentiated epithelial and mesenchymal cells acting as sensors and cell cycle keepers. Whereas cilia are essential along the airways, their regulatory molecular mechanisms remain poorly understood, resulting in a lack of therapeutic strategies targeting their structure or functions. This review summarises the current knowledge on cilia in the context of lung homeostasis and COPD to provide a comprehensive overview of the (patho)biology of cilia in respiratory medicine with a particular emphasis on COPD.