scholarly journals Ticlopidine in Its Prodrug Form Is a Selective Inhibitor of Human NTPDase1

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Joanna Lecka ◽  
Michel Fausther ◽  
Beat Künzli ◽  
Jean Sévigny
Keyword(s):  
Enzyme Histochemistry ◽  
Physiological Responses ◽  
Specific Inhibitor ◽  
Selective Inhibitor ◽  
Nucleoside Triphosphate ◽  
P2 Receptor ◽  
Extracellular Nucleotide ◽  
Nucleoside Triphosphate Diphosphohydrolase ◽  
Liver And Pancreas

Nucleoside triphosphate diphosphohydrolase-1 (NTPDase1), like other ectonucleotidases, controls extracellular nucleotide levels and consequently their (patho)physiological responses such as in thrombosis, inflammation, and cancer. Selective NTPDase1 inhibitors would therefore be very useful. We previously observed that ticlopidine in its prodrug form, which does not affect P2 receptor activity, inhibited the recombinant form of human NTPDase1 (Ki=14 μM). Here we tested whether ticlopidine can be used as a selective inhibitor of NTPDase1. We confirmed that ticlopidine inhibits NTPDase1 in different forms and in different assays. The ADPase activity of intact HUVEC as well as of COS-7 cells transfected with human NTPDase1 was strongly inhibited by 100 µM ticlopidine, 99 and 86%, respectively. Ticlopidine (100 µM) completely inhibited the ATPase activity of NTPDase1in situas shown by enzyme histochemistry with human liver and pancreas sections. Ticlopidine also inhibited the activity of rat and mouse NTPDase1 and of potato apyrase. At 100 µM ticlopidine did not affect the activity of human NTPDase2, NTPDase3, and NTPDase8, nor of NPP1 and NPP3. Weak inhibition (10–20%) of NTPDase3 and -8 was observed at 1 mM ticlopidine. These results show that ticlopidine is a specific inhibitor of NTPDase1 that can be used in enzymatic and histochemistry assays.

scholarly journals Osmotic surveillance mediates rapid wound closure through nucleotide release

2014 ◽  
Vol 207 (6) ◽  
pp. 767-782 ◽  
Author(s):  
William J. Gault ◽  
Balázs Enyedi ◽  
Philipp Niethammer
Keyword(s):  
Wound Repair ◽  
Interstitial Fluid ◽  
Wound Closure ◽  
External Environment ◽  
Atp Release ◽  
Nucleoside Triphosphate ◽  
Extracellular Nucleotide ◽  
Nucleoside Triphosphate Diphosphohydrolase ◽  
Larval Zebrafish ◽  
Zebrafish Larvae

Osmotic cues from the environment mediate rapid detection of epithelial breaches by leukocytes in larval zebrafish tail fins. Using intravital luminescence and fluorescence microscopy, we now show that osmolarity differences between the interstitial fluid and the external environment trigger ATP release at tail fin wounds to initiate rapid wound closure through long-range activation of basal epithelial cell motility. Extracellular nucleotide breakdown, at least in part mediated by ecto-nucleoside triphosphate diphosphohydrolase 3 (Entpd3), restricts the range and duration of osmotically induced cell migration after injury. Thus, in zebrafish larvae, wound repair is driven by an autoregulatory circuit that generates pro-migratory tissue signals as a function of environmental exposure of the inside of the tissue.

Beneficial effects of CD39/ecto-nucleoside triphosphate diphosphohydrolase-1 in murine intestinal ischemia-reperfusion injury

2004 ◽  
Vol 91 (03) ◽  
pp. 576-586 ◽  
Author(s):  
Olaf Guckelberger ◽  
Xiao Sun ◽  
Jean Sévigny ◽  
Masato Imai ◽  
Elzbieta Kaczmarek ◽  
...  
Keyword(s):  
Reperfusion Injury ◽  
Intestinal Ischemia ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Nucleoside Triphosphate ◽  
Wild Type ◽  
Extracellular Nucleotide ◽  
Vascular Integrity ◽  
Nucleoside Triphosphate Diphosphohydrolase ◽  
Intestinal Ischemia Reperfusion

SummaryCD39 (ecto-nucleoside triphosphate diphosphohydrolase-1; E-NTPDase-1), is highly expressed on quiescent vascular endothelial cells and efficiently hydrolyzes extracellular ATP and ADP to AMP and ultimately adenosine. This action blocks extracellular nucleotide-dependent platelet aggregation and abrogates endothelial cell activation. However, CD39 enzymatic activity is rapidly lost following exposure to oxidant stress. Modulation of extracellular nucleotide levels may therefore play an important role in the pathogenesis of vascular injury. Acute ischemic injury of the bowel is a serious medical condition characterized by high mortality rates with limited therapeutic options. Here we evaluate the effects of cd39-deletion in mutant mice and the use of supplemental NTPDase or adenosine in influencing the outcomes of intestinal ischemia-reperfusion. Wild-type, cd39null, or hemizygous cd39-deficient mice were subjected to intestinal ischemia. In selected animals, 0.2 U/g apyrase (soluble NTPDase) was administered prior to re-establishment of blood-flow. In parallel experiments adenosine/amrinone was infused over 60 min during reperfusion periods. Survival rates were determined, serum and tissue samples were taken. Intravital videomicroscopy and studies of vascular permeability were used to study platelet-endothelial cell interactions and determine capillary leakage. In wild-type animals, ischemia reperfusion injury resulted in 60% mortality within 48 hours. In mutant mice null or deficient for cd39, ischemia reperfusionrelated death occurred in 80% of animals. Apyrase supplementation protected all wild-type animals from death due to intestinal ischemia but did not fully protect cd39-null and cd39-hemizygote mice. Adenosine/amrinone treatment failed to improve survival figures. In wild type mice, platelet adherence to postcapillary venules was significantly decreased and vascular integrity was well preserved following apyrase administration. In cd39- null mice, ischemia-reperfusion induced marked albumin leakage indicative of heightened vascular permaeability when compared to wild-type animals (p=0.04). Treatment with NTPDase or adenosine supplementation abrogated the increased vascular permeability in ischemic jejunal specimens of both wild-type mice and cd39-null. CD39 activity modulates platelet activation and vascular leak during intestinal ischemia reperfusion injury in vivo. The potential of NTPDases to maintain vascular integrity suggests potential pharmacological benefit of these agents in mesenteric ischemic injury.

Differential catalytic properties and vascular topography of murine nucleoside triphosphate diphosphohydrolase 1 (NTPDase1) and NTPDase2 have implications for thromboregulation

Blood ◽  
2002 ◽  
Vol 99 (8) ◽  
pp. 2801-2809 ◽  
Author(s):  
Jean Sévigny ◽  
Christian Sundberg ◽  
Norbert Braun ◽  
Olaf Guckelberger ◽  
Eva Csizmadia ◽  
...  
Keyword(s):  
Platelet Aggregation ◽  
Adenosine Monophosphate ◽  
Adenosine Diphosphate ◽  
Receptor Activation ◽  
Extracellular Nucleotides ◽  
Nucleoside Triphosphate ◽  
Uridine Diphosphate ◽  
P2 Receptor ◽  
Nucleoside Triphosphate Diphosphohydrolase ◽  
Vessel Injury

Abstract Nucleoside triphosphate diphosphohydrolases (NTPDases) are a recently described family of ectonucleotidases that differentially hydrolyze the γ and β phosphate residues of extracellular nucleotides. Expression of this enzymatic activity has the potential to influence nucleotide P2 receptor signaling within the vasculature. We and others have documented that NTPDase1 (CD39, 78 kd) hydrolyzes both triphosphonucleosides and diphosphonucleosides and thereby terminates platelet aggregation responses to adenosine diphosphate (ADP). In contrast, we now show that NTPDase2 (CD39L1, 75 kd), a preferential nucleoside triphosphatase, activates platelet aggregation by converting adenosine triphosphate (ATP) to ADP, the specific agonist of P2Y1 and P2Y12 receptors. We developed specific antibodies to murine NTPDase1 and NTPDase2 and observed that both enzymes are present in the cardiac vasculature; NTPDase1 is expressed by endothelium, endocardium, and to a lesser extent by vascular smooth muscle, while NTPDase2 is associated with the adventitia of muscularized vessels, microvascular pericytes, and other cell populations in the subendocardial space. Moreover, NTPDase2 represents a novel marker for microvascular pericytes. Differential expression of NTPDases in the vasculature suggests spatial regulation of nucleotide-mediated signaling. In this context, NTPDase1 should abrogate platelet aggregation and recruitment in intact vessels by the conversion of ADP to adenosine monophosphate, while NTPDase2 expression would promote platelet microthrombus formation at sites of extravasation following vessel injury. Our data suggest that specific NTPDases, in tandem with ecto-5′-nucleotidase, not only terminate P2 receptor activation and trigger adenosine receptors but may also allow preferential activation of specific subsets of P2 receptors sensitive to ADP (eg, P2Y1, P2Y3, P2Y12) and uridine diphosphate (P2Y6).

Modulation of extracellular nucleotide-mediated signaling by CD39/nucleoside triphosphate diphosphohydrolase-1

2001 ◽  
Vol 53 (2-3) ◽  
pp. 193-207 ◽  
Author(s):  
Simon C. Robson ◽  
Keiichi Enjyoji ◽  
Christian Goepfert ◽  
Masato Imai ◽  
Elzbieta Kaczmarek ◽  
...  
Keyword(s):  
Nucleoside Triphosphate ◽  
Extracellular Nucleotide ◽  
Nucleoside Triphosphate Diphosphohydrolase

scholarly journals NTPDase1 Modulates Smooth Muscle Contraction in Mice Bladder by Regulating Nucleotide Receptor Activation Distinctly in Male and Female

Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 147
Author(s):  
Romuald Brice Babou Kammoe ◽  
Gilles Kauffenstein ◽  
Julie Pelletier ◽  
Bernard Robaye ◽  
Jean Sévigny
Keyword(s):  
Smooth Muscle ◽  
Ex Vivo ◽  
Smooth Muscle Contraction ◽  
Receptor Activation ◽  
Nucleoside Triphosphate ◽  
Nucleotide Receptors ◽  
Nerve Terminals ◽  
Wild Type ◽  
Nucleoside Triphosphate Diphosphohydrolase ◽  
Bladder Contraction

Nucleotides released by smooth muscle cells (SMCs) and by innervating nerve terminals activate specific P2 receptors and modulate bladder contraction. We hypothesized that cell surface enzymes regulate SMC contraction in mice bladder by controlling the concentration of nucleotides. We showed by immunohistochemistry, enzymatic histochemistry, and biochemical activities that nucleoside triphosphate diphosphohydrolase-1 (NTPDase1) and ecto-5′-nucleotidase were the major ectonucleotidases expressed by SMCs in the bladder. RT-qPCR revealed that, among the nucleotide receptors, there was higher expression of P2X1, P2Y1, and P2Y6 receptors. Ex vivo, nucleotides induced a more potent contraction of bladder strips isolated from NTPDase1 deficient (Entpd1−/−) mice compared to wild type controls. The strongest responses were obtained with uridine 5′-triphosphate (UTP) and uridine 5′-diphosphate (UDP), suggesting the involvement of P2Y6 receptors, which was confirmed with P2ry6−/− bladder strips. Interestingly, this response was reduced in female bladders. Our results also suggest the participation of P2X1, P2Y2 and/or P2Y4, and P2Y12 in these contractions. A reduced response to the thromboxane analogue U46619 was also observed in wild type, Entpd1−/−, and P2ry6−/− female bladders showing another difference due to sex. In summary, NTPDase1 modulates the activation of nucleotide receptors in mouse bladder SMCs, and contractions induced by P2Y6 receptor activation were weaker in female bladders.

scholarly journals Exposure to Electromagnetic Fields (EMF) from Submarine Power Cables Can Trigger Strength-Dependent Behavioural and Physiological Responses in Edible Crab, Cancer pagurus (L.)

2021 ◽  
Vol 9 (7) ◽  
pp. 776
Author(s):  
Kevin Scott ◽  
Petra Harsanyi ◽  
Blair A. A. Easton ◽  
Althea J. R. Piper ◽  
Corentine M. V. Rochas ◽  
...  
Keyword(s):  
Electromagnetic Field ◽  
Policy Making ◽  
Physiological Responses ◽  
Dependent Manner ◽  
Power Cables ◽  
Environmental Assessments ◽  
Cancer Pagurus ◽  
Commercially Important ◽  
Total Haemocyte Count

The current study investigated the effects of different strength Electromagnetic Field (EMF) exposure (250 µT, 500 µT, 1000 µT) on the commercially important decapod, edible crab (Cancer pagurus, Linnaeus, 1758). Stress related parameters were measured (l-Lactate, d-Glucose, Total Haemocyte Count (THC)) in addition to behavioural and response parameters (shelter preference and time spent resting/roaming) over 24 h periods. EMF strengths of 250 µT were found to have limited physiological and behavioural impacts. Exposure to 500 µT and 1000 µT were found to disrupt the l-Lactate and d-Glucose circadian rhythm and alter THC. Crabs showed a clear attraction to EMF exposed (500 µT and 1000 µT) shelters with a significant reduction in time spent roaming. Consequently, EMF emitted from MREDs will likely affect crabs in a strength-dependent manner thus highlighting the need for reliable in-situ measurements. This information is essential for policy making, environmental assessments, and in understanding the impacts of increased anthropogenic EMF on marine organisms.

scholarly journals Role of Ca2+ in Mediating Plant Responses to Extracellular ATP and ADP

2018 ◽  
Vol 19 (11) ◽  
pp. 3590 ◽  
Author(s):  
Greg Clark ◽  
Stanley Roux
Keyword(s):  
Cytosolic Calcium ◽  
Defense Responses ◽  
Receptor Activation ◽  
Extracellular Atp ◽  
Extracellular Nucleotides ◽  
Nucleoside Triphosphate ◽  
Plant Responses ◽  
Downstream Signaling ◽  
Nucleoside Triphosphate Diphosphohydrolase

Among the most recently discovered chemical regulators of plant growth and development are extracellular nucleotides, especially extracellular ATP (eATP) and extracellular ADP (eADP). Plant cells release ATP into their extracellular matrix under a variety of different circumstances, and this eATP can then function as an agonist that binds to a specific receptor and induces signaling changes, the earliest of which is an increase in the concentration of cytosolic calcium ([Ca2+]cyt). This initial change is then amplified into downstream-signaling changes that include increased levels of reactive oxygen species and nitric oxide, which ultimately lead to major changes in the growth rate, defense responses, and leaf stomatal apertures of plants. This review presents and discusses the evidence that links receptor activation to increased [Ca2+]cyt and, ultimately, to growth and diverse adaptive changes in plant development. It also discusses the evidence that increased [Ca2+]cyt also enhances the activity of apyrase (nucleoside triphosphate diphosphohydrolase) enzymes that function in multiple subcellular locales to hydrolyze ATP and ADP, and thus limit or terminate the effects of these potent regulators.

Sign in / Sign up

Export Citation Format

Share Document