Effective-Component Compatibility of Bufei Yishen Formula Ⅲ Ameliorated COPD By Improving Airway Epithelial Cell Senescence Via Promoting Mitophagy By Nrf2/PINK1 Pathway

Background: Effective-component compatibility of Bufei Yishen formula Ⅲ (ECC-BYF Ⅲ) shows positive effects on stable chronic obstructive pulmonary disease (COPD).Purpose: To investigate the mechanisms of ECC-BYF Ⅲ on COPD rats from the aspect of airway epithelial cell senescence.Methods: COPD model rats were treated with ECC-BYF Ⅲ for 8 weeks and the efficacy was evaluated. Cigarette smoke extract (CSE) induced senescence model of airway epithelial cells were treated with ECC-BYF Ⅲ, the related enzymes and proteins involved in oxidative stress and mitophagy were detected.Results: ECC-BYF Ⅲ markedly rescued pulmonary function and histopathological changes, which might be associated with the amelioration of lung senescence, including reduction of malondialdehyde (MDA) and tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and matrix metalloproteinase (MMP)-9, increase of the level of total superoxide dismutase (T-SOD), and decease of p21 level in airway. Furthermore, ECC-BYF Ⅲ suppressed p16, p21 expressions and senescence-associated β-galactosidase (SA-β-Gal) in CSE-induced airway epithelial cells. Moreover, ECC-BYF Ⅲ upregulated the mitophagy-related proteins, including co-localization of TOM20 and LC3B, PINK1, PARK2, and improved mitochondrial function with upregulating mitochondrial mitofusin (Mfn)2 and reducing dynamin-related protein 1 (Drp1) expression. ECC-BYF Ⅲ enhanced the activities of T-SOD and GSH-PX by up-regulating Nrf2, thus inhibiting oxidative stress. After intervention with Nrf2 inhibitor, the regulation effects of ECC-BYF Ⅲ on oxidative stress, mitophagy and senescence in airway epithelial cells were significantly suppressed.Conclusions: ECC-BYF Ⅲ exerts beneficial effects on COPD rats by ameliorating airway epithelial cell senescence, which is mediated by inhibiting oxidative stress and subsequently enhancing mitophagy through activation of Nrf2 signaling.

Establishment of well-differentiated camelid airway cultures to study Middle East respiratory syndrome coronavirus

In 2012, Middle East respiratory syndrome coronavirus (MERS-CoV) emerged in Saudi Arabia and was mostly associated with severe respiratory illness in humans. Dromedary camels are the zoonotic reservoir for MERS-CoV. To investigate the biology of MERS-CoV in camelids, we developed a well-differentiated airway epithelial cell (AEC) culture model for Llama glama and Camelus bactrianus. Histological characterization revealed progressive epithelial cellular differentiation with well-resemblance to autologous ex vivo tissues. We demonstrate that MERS-CoV displays a divergent cell tropism and replication kinetics profile in both AEC models. Furthermore, we observed that in the camelid AEC models MERS-CoV replication can be inhibited by both type I and III interferons (IFNs). In conclusion, we successfully established camelid AEC cultures that recapitulate the in vivo airway epithelium and reflect MERS-CoV infection in vivo. In combination with human AEC cultures, this system allows detailed characterization of the molecular basis of MERS-CoV cross-species transmission in respiratory epithelium.

The antimicrobial peptide S100A8/A9 produced by airway epithelium functions as a potent and direct regulator of macrophage phenotype and function

Elevated counts of alveolar macrophages and attenuated phagocytic capacity are associated with COPD. Factors governing macrophage phagocytosis are poorly understood. In this study we aimed to compare the influence of airway epithelial cell secretions from COPD and nonCOPD subjects on macrophage phagocytic activity, and the role of antimicrobial peptides (AMPs).Supernatants from nonCOPD and COPD small airway epithelial cell (SAEC) cultures exposed to Haemophilus influenzae (NTHi), were applied to human monocyte-derived macrophages (MDM) for assessment of their influence on phagocytosis. SAECs were analysed for changes in AMP expression by qRT-PCR and the influence of select AMPs on macrophage phenotype and function was assessed by flow cytometry and metabolic activity assay.Secretions from the apical and basolateral surface of NTHi-exposed SAECs from nonCOPD donors elicited superior phagocytic capacity of MDMs. Moreover, NTHi exposure led to a rapid increase in expression of a range of AMPs by nonCOPD SAECs, but this response was delayed in COPD SAECs. We demonstrate that treatment with AMPs β-defensin 2 and S100A8/A9 improved the phagocytic capacity of MDMs. In depth analysis of S100A8/A9 influence of MDMs revealed a role of this AMP in macrophage phenotype and function. Furthermore, we show that the expression of S100A8 and S100A9 is directly regulated by WNT/β-catenin signalling activity, a known deregulated pathway in COPD.In conclusion, for the first time, we demonstrate that airway epithelium from COPD subjects has a reduced capacity to support the phagocytic function of macrophages in response to acute NTHi exposure, and we identify the WNT/β-catenin signalling-modulated and epithelium-derived S100A8/A9 as a potent regulator of macrophage phenotype and function.

Impaired Ciliary Beat Frequency and Ciliogenesis Alteration during Airway Epithelial Cell Differentiation in COPD

Chronic obstructive pulmonary disease (COPD) is a frequent respiratory disease. However, its pathophysiology remains partially elucidated. Epithelial remodeling including alteration of the cilium is a major hallmark of COPD, but specific assessments of the cilium have been rarely investigated as a diagnostic tool in COPD. Here we explore the dysregulation of the ciliary function (ciliary beat frequency (CBF)) and differentiation (multiciliated cells formation in air-liquid interface cultures) of bronchial epithelial cells from COPD (n = 17) and non-COPD patients (n = 15). CBF was decreased by 30% in COPD (11.15 +/− 3.37 Hz vs. 7.89 +/− 3.39 Hz, p = 0.037). Ciliary differentiation was altered during airway epithelial cell differentiation from COPD patients. While the number of multiciliated cells decreased (p < 0.005), the number of primary ciliated cells increased (p < 0.05) and primary cilia were shorter (p < 0.05). Altogether, we demonstrate that COPD can be considered as a ciliopathy through both primary non-motile cilia modifications (related to airway epithelial cell repair and remodeling) and motile cilia function impairment (associated with decrease sputum clearance and clinical respiratory symptoms). These observations encourage considering cilia-associated features in the complex COPD physiopathology and highlight the potential of cilia-derived biomarkers for diagnosis.

Cystic Fibrosis and the Cells of the Airway Epithelium: What Are Ionocytes and What Do They Do?

Cystic fibrosis (CF) is caused by defects in an anion channel, the cystic fibrosis transmembrane conductance regulator (CFTR). Recently, a new airway epithelial cell type has been discovered and dubbed the pulmonary ionocyte. Unexpectedly, these ionocytes express higher levels of CFTR than any other airway epithelial cell type. However, ionocytes are not the sole CFTR-expressing airway epithelial cells, and CF-associated disease genes are in fact expressed in multiple airway epithelial cell types. The experimental depletion of ionocytes perturbs epithelial physiology in the mouse trachea, but the role of these rare cells in the pathogenesis of human CF remains mysterious. Ionocytes have been described in diverse tissues (kidney and inner ear) and species (frog and fish). We draw on these prior studies to suggest potential roles of airway ionocytes in health and disease. A complete understanding of ionocytes in the mammalian airway will ultimately depend on cell type–specific genetic manipulation Expected final online publication date for the Annual Review of Pathology: Mechanisms of Disease, Volume 17 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.