scholarly journals Glycated Albumin Triggers an Inflammatory Response in the Human Airway Epithelium and Causes an Increase in Ciliary Beat Frequency

2021 ◽  
Vol 12 ◽  
Author(s):  
Moira L. Aitken ◽  
Ranjani Somayaji ◽  
Thomas R. Hinds ◽  
Maricela Pier ◽  
Karla Droguett ◽  
...  

The role of inflammation in airway epithelial cells and its regulation are important in several respiratory diseases. When disease is present, the barrier between the pulmonary circulation and the airway epithelium is damaged, allowing serum proteins to enter the airways. We identified that human glycated albumin (GA) is a molecule in human serum that triggers an inflammatory response in human airway epithelial cultures. We observed that single-donor human serum induced IL-8 secretion from primary human airway epithelial cells and from a cystic fibrosis airway cell line (CF1-16) in a dose-dependent manner. IL-8 secretion from airway epithelial cells was time dependent and rapidly increased in the first 4 h of incubation. Stimulation with GA promoted epithelial cells to secrete IL-8, and this increase was blocked by the anti-GA antibody. The IL-8 secretion induced by serum GA was 10–50-fold more potent than TNFα or LPS stimulation. GA also has a functional effect on airway epithelial cells in vitro, increasing ciliary beat frequency. Our results demonstrate that the serum molecule GA is pro-inflammatory and triggers host defense responses including increases in IL-8 secretion and ciliary beat frequency in the human airway epithelium. Although the binding site of GA has not yet been described, it is possible that GA could bind to the receptor for advanced glycated end products (RAGE), known to be expressed in the airway epithelium; however, further experiments are needed to identify the mechanism involved. We highlight a possible role for GA in airway inflammation.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nadzeya Marozkina ◽  
Laura Smith ◽  
Yi Zhao ◽  
Joe Zein ◽  
James F. Chmiel ◽  
...  

AbstractEndothelial hemoglobin (Hb)α regulates endothelial nitric oxide synthase (eNOS) biochemistry. We hypothesized that Hb could also be expressed and biochemically active in the ciliated human airway epithelium. Primary human airway epithelial cells, cultured at air–liquid interface (ALI), were obtained by clinical airway brushings or from explanted lungs. Human airway Hb mRNA data were from publically available databases; or from RT-PCR. Hb proteins were identified by immunoprecipitation, immunoblot, immunohistochemistry, immunofluorescence and liquid chromatography- mass spectrometry. Viral vectors were used to alter Hbβ expression. Heme and nitrogen oxides were measured colorimetrically. Hb mRNA was expressed in human ciliated epithelial cells. Heme proteins (Hbα, β, and δ) were detected in ALI cultures by several methods. Higher levels of airway epithelial Hbβ gene expression were associated with lower FEV1 in asthma. Both Hbβ knockdown and overexpression affected cell morphology. Hbβ and eNOS were apically colocalized. Binding heme with CO decreased extracellular accumulation of nitrogen oxides. Human airway epithelial cells express Hb. Higher levels of Hbβ gene expression were associated with airflow obstruction. Hbβ and eNOS were colocalized in ciliated cells, and heme affected oxidation of the NOS product. Epithelial Hb expression may be relevant to human airways diseases.


1998 ◽  
Vol 274 (6) ◽  
pp. L893-L900 ◽  
Author(s):  
Gerene M. Denning ◽  
Michelle A. Railsback ◽  
George T. Rasmussen ◽  
Charles D. Cox ◽  
Bradley E. Britigan

Pseudomonas aeruginosa, an opportunistic human pathogen, causes both acute and chronic lung disease. P. aeruginosa exerts many of its pathophysiological effects by secreting virulence factors, including pyocyanine, a redox-active compound that increases intracellular oxidant stress. Because oxidant stress has been shown to affect cytosolic Ca2+concentration ([Ca2+]c) in other cell types, we studied the effect of pyocyanine on [Ca2+]cin human airway epithelial cells (A549 and HBE). At lower concentrations, pyocyanine inhibits inositol 1,4,5-trisphosphate formation and [Ca2+]cincreases in response to G protein-coupled receptor agonists. Conversely, at higher concentrations, pyocyanine itself increases [Ca2+]c. The pyocyanine-dependent [Ca2+]cincrease appears to be oxidant dependent and to result from increased inositol trisphosphate and release of Ca2+from intracellular stores. Ca2+plays a central role in epithelial cell function, including regulation of ion transport, mucus secretion, and ciliary beat frequency. By disrupting Ca2+homeostasis, pyocyanine could interfere with these critical functions and contribute to the pathophysiological effects observed in Pseudomonas-associated lung disease.


1995 ◽  
Vol 268 (4) ◽  
pp. L596-L600 ◽  
Author(s):  
J. H. Sisson

The mucociliary apparatus of the lung provides an important host-defense function by clearing the upper airway of inhaled particles and infectious microorganisms. Because lung host defenses are impaired in alcoholics, we hypothesized that ethanol would decrease ciliary motility in airway epithelium. Ciliary beat frequency (CBF) was measured by videomicroscopy in primary cultures of ciliated bovine bronchial epithelial cells (BBECs). Ethanol rapidly stimulated ciliary motility in a time-dependent fashion with concentrations as low as 10 mM. No detectable decreases in ciliary motility were noted until ethanol concentrations exceeded 1,000 mM. Because many substances stimulate ciliary motility by releasing nitric oxide (NO) via upregulation of nitric oxide synthase (NOS), we preincubated ciliated BBECs with a stereospecific NOS inhibitor, NG-monomethyl-L-arginine (L-NMMA). L-NMMA completely blocked ethanol-induced stimulation of CBF, which could be subsequently restored by adding either L-arginine or sodium nitroprusside, which is a direct NO donor. These results indicate that ethanol, at clinically relevant concentrations, stimulates the release of NO by airway epithelium that upregulates ciliary motility. The rapidity of this response suggests upregulation of the constitutive NOS, known to be present in airway epithelium, and may explain the increases in mucociliary clearance observed in previous studies of ethanol ingestion in animals and in humans. These data also suggest a novel signal transduction pathway, the NO/NOS system, by which ethanol may exert some of its diverse biologic effects.


1998 ◽  
Vol 275 (4) ◽  
pp. L827-L835 ◽  
Author(s):  
T. A. Wyatt ◽  
J. R. Spurzem ◽  
K. May ◽  
J. H. Sisson

Ciliary beating is required for the maintenance of lung mucociliary transport. We investigated the role of cyclic nucleotide-dependent protein kinases in stimulating ciliary beat frequency (CBF) in bovine bronchial epithelial cells (BBECs). cAMP-dependent protein kinase (PKA) activity and cGMP-dependent protein kinase (PKG) activity were distinguished after DEAE-Sephacel chromatography of BBEC extracts. cAMP levels and PKA activity are increased in BBECs stimulated with 0.01–1 mM isoproterenol, with a corresponding increase in CBF. cGMP levels and PKG activity are increased in BBECs stimulated with 0.1–10 μM sodium nitroprusside, with a corresponding increase in CBF. Direct protein kinase-activating analogs of cAMP and cGMP (dibutyryl cAMP and 8-bromo-cGMP, respectively) also activate their specific kinases and stimulate CBF. Preincubation of BBECs with inhibitors of PKA or PKG [KT-5720 or Rp-8-( p-chlorophenylthio)-guanosine 3′,5′-cyclic monophosphothioate] results in the inhibition of specific kinase activity as well as in the inhibition of CBF. These studies suggest that the activation of either PKA or PKG can lead to the stimulation of CBF in bovine airway epithelium.


2020 ◽  
Vol 319 (1) ◽  
pp. L126-L136
Author(s):  
Alekh Paranjapye ◽  
Michael J. Mutolo ◽  
Jey Sabith Ebron ◽  
Shih-Hsing Leir ◽  
Ann Harris

The differentiated functions of the human airway epithelium are coordinated by a complex network of transcription factors. These include the pioneer factors Forkhead box A1 and A2 (FOXA1 and FOXA2), which are well studied in several tissues, but their role in airway epithelial cells is poorly characterized. Here, we define the cistrome of FOXA1 and FOXA2 in primary human bronchial epithelial (HBE) cells by chromatin immunoprecipitation with deep-sequencing (ChIP-seq). Next, siRNA-mediated depletion of each factor is used to investigate their transcriptome by RNA-seq. We found that, as predicted from their DNA-binding motifs, genome-wide occupancy of the two factors showed substantial overlap; however, their global impact on gene expression differed. FOXA1 is an abundant transcript in HBE cells, while FOXA2 is expressed at low levels, and both these factors likely exhibit autoregulation and cross-regulation. FOXA1 regulated loci are involved in cell adhesion and the maintenance of epithelial cell identity, particularly through repression of genes associated with epithelial to mesenchymal transition (EMT). FOXA1 also directly targets other transcription factors with a known role in the airway epithelium such as SAM-pointed domain-containing Ets-like factor (SPDEF). The intersection of the cistrome and transcriptome for FOXA1 revealed enrichment of genes involved in epithelial development and tissue morphogenesis. Moreover, depletion of FOXA1 was shown to reduce the transepithelial resistance of HBE cells, confirming the role of this factor in maintaining epithelial barrier integrity.


1995 ◽  
Vol 268 (6) ◽  
pp. L911-L917 ◽  
Author(s):  
B. Jain ◽  
I. Rubinstein ◽  
R. A. Robbins ◽  
J. H. Sisson

Airway epithelial cells can be modulated by cytokines such as tumor necrosis factor (TNF)-alpha and interleukin (IL)-1 beta that are released from inflammatory cells. Since ciliary motility is an important host defense function of airway epithelium, we hypothesized that cytokines, released from lung macrophages, upregulate ciliary motility. To test this hypothesis, ciliary beat frequency (CBF) was measured by video microscopy in cultured ciliated bovine bronchial epithelial cells (BBECs) incubated for 24 h with bovine alveolar macrophage-conditioned medium (AM-CM). Exposure to AM-CM resulted in a delayed (> or = 2 h) increase in CBF that was maximal after 24 h exposure (13.70 +/- 0.43 for AM-CM vs. 9.44 +/- 0.24 Hz for medium; P < 0.0001) and which was largely blocked by either anti-TNF-alpha or anti-IL-1 beta antibodies. rTNF-alpha or rIL-1 beta similarly increased CBF, which could be blocked by preincubation with either anti-rTNF-alpha or anti-rIL-1 beta antibodies. Preincubation of BBECs with actinomycin D or dexamethasone also blocked rTNF-alpha- and rIL-1 beta-induced cilia stimulation, suggesting that new protein synthesis is required for cytokine-induced upregulation of CBF. Since NO is known to upregulate ciliary motility and cytokines can induce NO synthase (NOS), we hypothesized that TNF-alpha and IL-1 beta increase CBF by inducing NOS in BBECs. The cilia stimulatory effects of TNF-alpha or IL-1 beta were inhibited by NG-monomethyl-L-arginine, a competitive NOS inhibitor, and restored by the addition of either L-arginine, an NOS substrate, or sodium nitroprusside, an NO donor.(ABSTRACT TRUNCATED AT 250 WORDS)


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