scholarly journals Extracellular ATP and P2Y Receptor Activation Induce a Proinflammatory Host Response in the Human Urinary Tract

2010 ◽  
Vol 78 (8) ◽  
pp. 3609-3615 ◽  
Author(s):  
Susanne Säve ◽  
Katarina Persson
Keyword(s):  
Urinary Tract ◽  
Cell Line ◽  
Atp Release ◽  
Receptor Activation ◽  
Extracellular Atp ◽  
Luciferase Assay ◽  
Enzyme Linked Immunosorbent Assay ◽  
Epithelial Cell Line ◽  
P2y Receptor ◽  
Uroepithelial Cells

ABSTRACT Extracellular ATP can be released by many cell types under conditions of cellular stress and signals through activation of purinergic receptors. Bladder uroepithelial cells grown in vitro have previously been shown to release ATP in response to stretch. In the present study, we investigated ATP release from uroepithelial cells infected with bacteria and the effect of ATP on the host cell proinflammatory interleukin 8 (IL-8) response. The human kidney epithelial cell line A498 and the human uroepithelial cell line UROtsa were grown in culture and stimulated by the uropathogenic Escherichia coli (UPEC) IA2 strain or the stable ATP analogue ATP-γ-S. ATP and IL-8 levels were measured in cell culture medium with a luciferin-luciferase assay and enzyme-linked immunosorbent assay (ELISA), respectively. The results showed that UPEC infection of uroepithelial cells for 1 h significantly increased (P < 0.01) the extracellular ATP levels. ATP-γ-S (10 and 100 μM) stimulated release of IL-8 from UROtsa and A498 cells after 6 and 24 h. Experiments with different purinoceptor agonists suggested that P2Y receptors, and not P2X receptors, were responsible for the ATP-γ-S-induced IL-8 release. The potency profile further suggested involvement of P2Y1, P2Y2, and/or P2Y11 receptors, and reverse transcription-PCR (RT-PCR) studies confirmed that the cells expressed these receptors. The amount of IL-8 released increased 12-fold in UPEC-infected cells, and apyrase, an enzyme that degrades ATP, reduced this increase by approximately 50%. The present study suggests that enhanced ATP release and P2Y receptor activation during urinary tract infection may represent a novel, non-TLR4-mediated mechanism for production of proinflammatory IL-8 in human urinary tract epithelial cells.

Extracellular ATP Modulates Ion Transport via P2Y Purinoceptors in a Middle-Ear Epithelial Cell Line

ORL ◽  
1997 ◽  
Vol 59 (3) ◽  
pp. 170-175 ◽  
Author(s):  
P.-T. Yen ◽  
P. Herman ◽  
T. van den Abbeele ◽  
C.-T. Tan ◽  
P. Bordure ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Ion Transport ◽  
Cell Line ◽  
Middle Ear ◽  
Extracellular Atp ◽  
Epithelial Cell Line

Sustained depolarization-induced propagation of [Ca2+]i oscillations in cultured DRG neurons: The involvement of extracellular ATP and P2Y receptor activation

2008 ◽  
Vol 1239 ◽  
pp. 12-23 ◽  
Author(s):  
Yan Zeng ◽  
Xiao-hua Lv ◽  
Shao-qun Zeng ◽  
Shun-lian Tian ◽  
Man Li ◽  
...  
Keyword(s):  
Receptor Activation ◽  
Extracellular Atp ◽  
P2y Receptor ◽  
Drg Neurons

Blocking ATP releasing channels prevents high extracellular ATP levels and airway hyperreactivity in an asthmatic mouse model

2021 ◽  
Author(s):  
Llilian Arzola Martínez ◽  
Rebeca Benavente ◽  
Génesis Vega ◽  
Mariana Ríos ◽  
Wendy Fonseca ◽  
...  
Keyword(s):  
Mouse Model ◽  
Airway Inflammation ◽  
Airway Epithelium ◽  
Atp Release ◽  
Specific Inhibitor ◽  
Extracellular Atp ◽  
Airway Hyperreactivity ◽  
Luciferase Assay ◽  
Asthmatic Patients ◽  
Allergic Mouse

Allergic asthma is a chronic airway inflammatory response to different triggers like inhaled allergens. Excessive ATP in fluids from asthmatic patients is considered an inflammatory signal and an important autocrine/paracrine modulator of airway physiology. Here we investigated the deleterious effect of increased extracellular ATP (eATP) concentration on the mucociliary clearance (MCC) effectiveness and determined the role of ATP releasing channels during airway inflammation in an ovalbumin (OVA)-sensitized mouse model. Our allergic mouse model exhibited high levels of eATP measured in the tracheal fluid with a luciferin-luciferase assay and reduced MCC velocity determined by microspheres tracking in the trachea ex vivo. Addition of ATP had a dual effect on MCC, where lower ATP concentration (µM) increased microspheres velocity, while higher concentration (mM) transiently stopped microspheres movement. Also, an augmented ethidium bromide uptake by the allergic tracheal airway epithelium suggests an increase in ATP release channel functionality during inflammatory conditions. The use of carbenoxolone, a non-specific inhibitor of connexin and pannexin1channels reduced the eATP concentration in the allergic mouse tracheal fluid and dye uptake by the airway epithelium, providing evidence that these ATP release channels are facilitating the net flux of ATP to the lumen during airway inflammation. However, only the specific inhibition of pannexin1 with 10Panx peptide significantly reduced eATP in bronchoalveolar lavage and decreased airway hyperresponsiveness in OVA-allergic mouse model. These data provide evidence that blocking eATP may be a pharmacological alternative to be explored in rescue therapy during episodes of airflow restriction in asthmatic patients.

scholarly journals P2X1 receptor activation in HL60 cells

Blood ◽  
1996 ◽  
Vol 87 (7) ◽  
pp. 2659-2664 ◽  
Author(s):  
G Buell ◽  
AD Michel ◽  
C Lewis ◽  
G Collo ◽  
PP Humphrey ◽  
...  
Keyword(s):  
Messenger Rna ◽  
Radioligand Binding ◽  
Atp Release ◽  
Receptor Activation ◽  
P2x Receptor ◽  
Luciferase Assay ◽  
Receptor Protein ◽  
Hl60 Cells ◽  
P2x1 Receptor ◽  
Alpha Beta

Recent cloning of the human P2X1 receptor revealed high levels of its messenger RNA in differentiated promyelocytes (HL60 cells). We found expression of P2X1 receptor protein in HL60 cells by radioligand binding, by immunohistochemistry, using a receptor specific antibody, and by electrophysiology. The currents elicited by adenosine triphosphate (ATP) had the expected properties of P2X1 receptors (rapid desensitization, mimicked by alpha,beta-methylene-ATP). However, these currents were only observed in cells that were pretreated with apyrase, which destroys extracellular ATP, or with suramin, a P2X receptor antagonist. This implies that HL60 cells release ATP, which chronically desensitizes the receptor. ATP release was detected by direct measurement, using the luciferin-luciferase assay. It is concluded that functional P2X1 receptors are present in the membrane of differentiated HL60 cells.

scholarly journals Modulation of Porcine β-Defensins 1 and 2 upon Individual and Combined Fusarium Toxin Exposure in a Swine Jejunal Epithelial Cell Line

2013 ◽  
Vol 79 (7) ◽  
pp. 2225-2232 ◽  
Author(s):  
Murphy Lam-Yim Wan ◽  
Chit-Shing Jackson Woo ◽  
Kevin J. Allen ◽  
Paul C. Turner ◽  
Hani El-Nezami
Keyword(s):  
Epithelial Cell ◽  
Mrna Expression ◽  
Cell Line ◽  
Defense Mechanisms ◽  
Fumonisin B1 ◽  
Enzyme Linked Immunosorbent Assay ◽  
Epithelial Cell Line ◽  
Content Type ◽  
Antimicrobial Effects ◽  
Food And Feed

ABSTRACTDefensins are small antimicrobial peptides (AMPs) that play an important role in the innate immune system of mammals. Since the effect of mycotoxin contamination of food and feed on the secretion of intestinal AMPs is poorly understood, the aim of this study was to elucidate the individual and combined effects of four commonFusariumtoxins, deoxynivalenol (DON), nivalenol (NIV), zearalenone (ZEA), and fumonisin B1 (FB1), on the mRNA expression, protein secretion, and corresponding antimicrobial effects of porcine β-defensins 1 and 2 (pBD-1 and pBD-2) using a porcine jejunal epithelial cell line, IPEC-J2. In general, upregulation of pBD-1 and pBD-2 mRNA expression occurred following exposure toFusariumtoxins, individually and in mixtures (P< 0.05). However, no significant increase in secreted pBD-1 and pBD-2 protein levels was observed, as measured by enzyme-linked immunosorbent assay (ELISA). Supernatants from IPEC-J2 cells exposed to toxins, singly or in combination, however, possessed significantly less antimicrobial activity againstEscherichia colithan untreated supernatants. When single toxins and two-toxin combinations were assessed, toxicity effects were shown to be nonadditive (including synergism, potentiation, and antagonism), suggesting interactive toxin effects when cells are exposed to mycotoxin combinations. The results show thatFusariumtoxins, individually and in mixtures, activate distinct antimicrobial defense mechanisms possessing the potential to alter the intestinal microbiota through diminished antimicrobial effects. Moreover, by evaluating toxin mixtures, this improved understanding of toxin effects will enable more effective risk assessments for common mycotoxin combinations observed in contaminated food and feed.

scholarly journals P2Y Receptor Modulation of ATP Release in the Urothelium

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Kylie J. Mansfield ◽  
Jessica R. Hughes
Keyword(s):  
Atp Release ◽  
Receptor Activation ◽  
P2y Receptor ◽  
P2 Receptor ◽  
Urothelial Cells ◽  
Receptor Agonists ◽  
Receptor Signalling ◽  
Receptor Modulation ◽  
High Concentrations ◽  
Stimulation Of

The release of ATP from the urothelium in response to stretch during filling demonstrates the importance of the purinergic system for the physiological functioning of the bladder. This study examined the effect of P2 receptor agonists on ATP release from two urothelial cell lines (RT4 and UROtsa cells). Hypotonic Krebs was used as a stretch stimulus. Incubation of urothelial cells with high concentrations of the P2Y agonist ADP induced ATP release to a level that was 40-fold greater than hypotonic-stimulated ATP release (P< 0.0011, ADP EC50 1.8 µM). Similarly, an increase in ATP release was also observed with the P2Y agonist, UTP, up to a maximum of 70% of the hypotonic response (EC50 0.62 µM). Selective P2 receptor agonists,αβ-methylene-ATP, ATP-γ-S, and 2-methylthio-ADP had minimal effects on ATP release. ADP-stimulated ATP release was significantly inhibited by suramin (100 µM,P= 0.002). RT4 urothelial cells break down nucleotides (100 µM) including ATP, ADP, and UTP to liberate phosphate. Phosphate liberation was also demonstrated from endogenous nucleotides with approximately 10% of the released ATP broken down during the incubation. These studies demonstrate a role for P2Y receptor activation in stimulation of ATP release and emphasize the complexity of urothelial P2 receptor signalling.

scholarly journals ATF2 partly mediated the expressions of proliferative factors and inhibited pro-inflammatory factors’ secretion in arsenite-treated human uroepithelial cells

2017 ◽  
Vol 6 (4) ◽  
pp. 468-476
Author(s):  
Shengnan Liu ◽  
Fei Wang ◽  
Jieyu Liu ◽  
Peiyu Jin ◽  
Xiaoyan Wang ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Epithelial Cell ◽  
Urinary Bladder ◽  
Cell Line ◽  
Inflammatory Factors ◽  
Epithelial Cell Line ◽  
Bladder Epithelial Cell ◽  
Human Urinary Bladder ◽  
Uroepithelial Cells ◽  
Activating Transcription Factor

Activating transcription factor 2 (ATF2) was involved in the expressions of proliferative factors in arsenite treated human urinary bladder epithelial cell line (SV-HUC-1 cells).

Augmented extracellular ATP signaling in bladder urothelial cells from patients with interstitial cystitis

2006 ◽  
Vol 290 (1) ◽  
pp. C27-C34 ◽  
Author(s):  
Yan Sun ◽  
Toby C. Chai
Keyword(s):  
Interstitial Cystitis ◽  
Purinergic Signaling ◽  
Atp Release ◽  
Extracellular Atp ◽  
Luciferase Assay ◽  
Heparin Binding ◽  
Urothelial Cells ◽  
Atp Levels ◽  
And Control ◽  
Atp Signaling

Interstitial cystitis (IC) is an idiopathic hypersensory condition of the bladder associated with increased urinary ATP and increased stretch-activated ATP release by bladder urothelial cells (BUCs), suggesting augmented purinergic signaling in the bladder. To test this theory further, monolayers of cultured BUCs derived from bladder biopsies obtained from patients with IC and control patients were stimulated with 10–30 μM ATP with subsequent measurement of extracellular ATP levels using the luciferin-luciferase assay. Stimulation with 30 μM ATP resulted in IC supernatant containing several-fold more ATP than control BUCs initially, followed by a slower decrease in ATP levels. This difference in ATP levels was not completely due to activity of cellular ecto-ATPase, because blockade with ARL67156 did not normalize the difference. Exposure to hypotonic solutions resulted in similar extracellular ATP concentrations in IC and control BUCs, but there was a slower decrease in ATP levels in IC supernatants. Treatment of IC BUCs with 10–40 μM suramin, a nonspecific P2 receptor antagonist, significantly attenuated the IC BUC response to extracellular ATP, restoring IC BUCs to a control phenotype. Pretreatment of IC BUCs with 20 ng/ml of heparin-binding EGF-like growth factor (HB-EGF), which previously has been shown to be decreased in IC urine specimens, also restored IC BUCs to a control phenotype with respect to response to ATP stimulation. In conclusion, IC BUCs have augmented extracellular ATP signaling that could be blocked by suramin and HB-EGF. These findings suggest the possible development of future novel therapeutic techniques.

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