Alterations of nitric oxide synthase expression and activity during rat lung transplantation

2000 ◽  
Vol 278 (5) ◽  
pp. L1071-L1081 ◽  
Author(s):  
Mingyao Liu ◽  
Lorraine Tremblay ◽  
Stephen D. Cassivi ◽  
Xiao-Hui Bai ◽  
Eric Mourgeon ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Lung Transplantation ◽  
Ex Vivo ◽  
Total Activity ◽  
No Production ◽  
Ex Vivo Model ◽  
Gene And Protein Expression ◽  
Lung Transplants ◽  
Inducible Nos

Decreased nitric oxide (NO) production has been reported during lung transplantation in patients. To study the effects of ischemia and reperfusion on endogenous NO synthase (NOS) expression, both an ex vivo and an in vivo lung injury model for transplantation were used. Donor rat lungs were flushed with cold low-potassium dextran solution and subjected to either cold (4°C for 12 h) or warm (21°C for 4 h) ischemic preservation followed by reperfusion with an ex vivo model. A significant increase in inducible NOS and a decrease in endothelial NOS mRNA was found after reperfusion. These results were confirmed in a rat single-lung transplant model after warm preservation. Interestingly, protein contents of both inducible NOS and endothelial NOS increased in the transplanted lung after 2 h of reperfusion. However, the total activity of NOS in the transplanted lungs remained at very low levels. We conclude that ischemic lung preservation and reperfusion result in altered NOS gene and protein expression with inhibited NOS activity, which may contribute to the injury of lung transplants.

Abstract 15: Novel Functions of Small GTPase Rap1 in Regulating Endothelial Homeostasis: Control of Nitric Oxide Release, Vascular Function and Blood Pressure

2014 ◽  
Vol 34 (suppl_1) ◽  
Author(s):  
Sribalaji Lakshmikanthan ◽  
Xiaodong Zheng ◽  
Yoshinori Nishijima ◽  
Jeannette Vasquez-Vivar ◽  
David X Zhang ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Blood Pressure ◽  
Shear Flow ◽  
Knockout Mice ◽  
Ex Vivo ◽  
Left Ventricular ◽  
Small Gtpase ◽  
No Production ◽  
Endothelial Homeostasis

Endothelial dysfunction, resulting from decreased nitric oxide (NO) bioavailability is a pathology linked to endothelial vasomotor dysfunction and hypertension, inflammation and atherosclerosis, perturbed endothelial barrier and progression of diabetes. In blood vessels, NO is produced by the endothelial NO synthase (eNOS), the activity of which is regulated by Ca2+/calmodulin, binding of regulatory cofactors, and posttranslational modifications, including phosphorylation events on Ser1177, which stimulate NO production. Rap1 is a ubiquitously expressed small GTPase implicated in promoting vascular barrier. We have shown that endothelial cell (EC)-specific Rap1 deletion leads to defective angiogenesis in vivo due to faulty VEGFR2 activation and signaling. Importantly, EC-specific Rap1 knockout mice developed hypertension and pathological left ventricular hypertrophy. The objective of the study was to determine the role of small G protein Rap1 in regulating endothelial NO production and endothelial-dependent vasorelaxation in vivo and ex vivo. Using ex vivo myography and tamoxifen-inducible, endothelial-specific Rap1-knockout mice (Cadh5-CreERT2+/0;Rap1f/f), we demonstrate that Rap1 deficiency completely abrogates NO-dependent vasodilation and attenuates NO production. Mechanistically, we show that Rap1 is rapidly activated in response to receptor agonists that activate eNOS via Ca2+/calmodulin- dependent pathway and in response to shear flow, which modules eNOS activity by its phosphorylation. Rap1 deletion in human ECs, in vitro, leads to deficient NO release in response to both these stimuli, and interferes with PI3K/Akt pathway and eNOS Ser1177 phosphorylation. Further, we demonstrate Rap1 is required for transducing signals from the endothelial mechanosensing complex comprising PECAM-1, VE-cadherin and VEGFR2 in response to shear flow, leading to ligand-independent VEGFR2 activation and signaling to stimulate NO production. We conclude that Rap1 in endothelium is critically required for endothelial homeostasis and NO production, thereby affecting vascular tone and regulation of blood pressure. Furthermore, this study establishes Rap1 as a novel regulator of mechanotransduction in response to shear flow.

In vivo three-dimensional EPR imaging of nitric oxide production from isosorbide dinitrate in mice

1998 ◽  
Vol 274 (5) ◽  
pp. G857-G862 ◽  
Author(s):  
Satoshi Fujii ◽  
Yasuhiro Suzuki ◽  
Tetsuhiko Yoshimura ◽  
Hitoshi Kamada
Keyword(s):  
Nitric Oxide ◽  
Isosorbide Dinitrate ◽  
Epr Spectroscopy ◽  
Ex Vivo ◽  
Three Dimensional ◽  
Water Soluble ◽  
Whole Body ◽  
No Production ◽  
Epr Signal

Recently, in vivo electron paramagnetic resonance (EPR) spectroscopy and imaging have been widely used to investigate free radical distribution and metabolism in tissues, organs, and whole body of small animals. Endogenous nitric oxide (NO) is an attractive target of this method. In the present study, NO production from a nitrovasodilator, isosorbide dinitrate (ISDN), in live mice was investigated by in vivo EPR spectroscopy and imaging combined with the spin-trapping technique. A highly water-soluble Fe complex with N-(dithiocarboxy)sarcosine (DTCS) was used as an NO-trapping agent. Mice received [14N]ISDN, and the Fe-DTCS complex subcutaneously exhibited the characteristic triplet EPR signal of the NO adduct [14NO-Fe(DTCS)2]2−. Using [15N]ISDN instead of [14N]ISDN, we were able to observe that the doublet EPR signal stemmed from the15NO adduct, which directly demonstrated that NO was produced from ISDN. The three-dimensional EPR images of the upper abdomen of living mice showed that the NO adducts were distributed in the liver and the kidneys. This EPR image combined with the ex vivo EPR measurements of the blood suggested that NO production from ISDN occurred in the liver in this experimental condition.

scholarly journals Hormonal and Spatial Regulation of Nitric Oxide Synthases (NOS) (Neuronal NOS, Inducible NOS, and Endothelial NOS) in the Oviducts

Endocrinology ◽  
2006 ◽  
Vol 147 (12) ◽  
pp. 5600-5610 ◽  
Author(s):  
Jérome Lapointe ◽  
Monica Roy ◽  
Isabelle St-Pierre ◽  
Sarah Kimmins ◽  
Danny Gauvreau ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Hormonal Regulation ◽  
Early Embryo ◽  
Pcr Analysis ◽  
No Production ◽  
Final Maturation ◽  
Neuronal Nos ◽  
Reproductive Events ◽  
Inducible Nos

Nitric oxide (NO) is a free radical produced by the action of NO synthases (NOS) and is known to be involved in the regulation of many reproductive events that occur in the oviducts. The oviducts are highly specialized organs that play crucial roles in reproduction by providing an optimal environment for the final maturation of gametes, fertilization, and early embryo development. In this study, we analyzed the expression, hormonal regulation, and cellular distribution of neuronal, inducible, and endothelial NOS in different bovine oviduct segments to better understand the roles played by these enzymes in oviductal functions in vivo. Quantitative RT-PCR analysis revealed that NOS isoforms are hormonally regulated and differentially expressed along the oviduct throughout the estrous cycle. All NOS were highly expressed around the time of estrus, and immunohistochemistry studies determined that neuronal NOS, inducible NOS (iNOS), and endothelial NOS are differentially distributed in cells along the oviduct. Interestingly, our results showed that estradiol selectively up-regulates iNOS expression in the oviduct during the periovulatory period corresponding to the window of ovulation, oocyte transport, and fertilization. The resulting NO production by this high-output NOS may be of crucial importance for reproductive events that occur in the oviduct. This study provided the first demonstration that NO production is hormonally regulated in the mammalian oviducts in vivo. Our results suggest that neuronal NOS, iNOS, and endothelial NOS contribute to oviductal functions in a timely and site-specific manner.

scholarly journals Effects of chitosan on nitric oxide production and inducible nitric oxide synthase activity and mRNA expression in weaned piglets

2018 ◽  
Vol 60 (No. 8) ◽  
pp. 359-366
Author(s):  
J. Li ◽  
B. Shi ◽  
S. Yan ◽  
L. Jin ◽  
Y. Guo ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Mrna Expression ◽  
Inducible Nitric Oxide Synthase ◽  
No Production ◽  
Weaned Piglets ◽  
Inos Activity ◽  
Oxide Synthase ◽  
Inducible Nitric Oxide

The effects of chitosan on nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) activity and gene expression in vivo or vitro were investigated in weaned piglets. In vivo, 180 weaned piglets were assigned to five dietary treatments with six replicates. The piglets were fed on a basal diet supplemented with 0 (control), 100, 500, 1000, and 2000 mg chitosan/kg feed, respectively. In vitro, the peripheral blood mononuclear cells (PBMCs) from a weaned piglet were cultured respectively with 0 (control), 40, 80, 160, and 320 µg chitosan/ml medium. Results showed that serum NO concentrations on days 14 and 28 and iNOS activity on day 28 were quadratically improved with increasing chitosan dose (P < 0.05). The iNOS mRNA expressions were linearly or quadratically enhanced in the duodenum on day 28, and were improved quadratically in the jejunum on days 14 and 28 and in the ileum on day 28 (P < 0.01). In vitro, the NO concentrations, iNOS activity, and mRNA expression in unstimulated PBMCs were quadratically enhanced by chitosan, but the improvement of NO concentrations and iNOS activity by chitosan were markedly inhibited by N-(3-[aminomethyl] benzyl) acetamidine (1400w) (P < 0.05). Moreover, the increase of NO concentrations, iNOS activity, and mRNA expression in PBMCs induced by lipopolysaccharide (LPS) were suppressed significantly by chitosan (P < 0.05). The results indicated that the NO concentrations, iNOS activity, and mRNA expression in piglets were increased by feeding chitosan in a dose-dependent manner. In addition, chitosan improved the NO production in unstimulated PBMCs but inhibited its production in LPS-induced cells, which exerted bidirectional regulatory effects on the NO production via modulated iNOS activity and mRNA expression.

Expression of β-defensin-4 in “an in vivo and ex vivo model” of human osteoarthritic knee meniscus

2011 ◽  
Vol 20 (2) ◽  
pp. 216-222 ◽  
Author(s):  
Giuseppe Musumeci ◽  
Maria Luisa Carnazza ◽  
Rosalia Leonardi ◽  
Carla Loreto
Keyword(s):  
Ex Vivo ◽  
Ex Vivo Model ◽  
Osteoarthritic Knee ◽  
Knee Meniscus

scholarly journals Considerations to Model Heart Disease in Women with Preeclampsia and Cardiovascular Disease

Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 899
Author(s):  
Clara Liu Chung Ming ◽  
Kimberly Sesperez ◽  
Eitan Ben-Sefer ◽  
David Arpon ◽  
Kristine McGrath ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Cardiovascular Disease ◽  
Ex Vivo ◽  
Myocardial Damage ◽  
Cardiovascular Disorder ◽  
Model Systems ◽  
Ex Vivo Model ◽  
Disease Manifestation

Preeclampsia is a multifactorial cardiovascular disorder diagnosed after 20 weeks of gestation, and is the leading cause of death for both mothers and babies in pregnancy. The pathophysiology remains poorly understood due to the variability and unpredictability of disease manifestation when studied in animal models. After preeclampsia, both mothers and offspring have a higher risk of cardiovascular disease (CVD), including myocardial infarction or heart attack and heart failure (HF). Myocardial infarction is an acute myocardial damage that can be treated through reperfusion; however, this therapeutic approach leads to ischemic/reperfusion injury (IRI), often leading to HF. In this review, we compared the current in vivo, in vitro and ex vivo model systems used to study preeclampsia, IRI and HF. Future studies aiming at evaluating CVD in preeclampsia patients could benefit from novel models that better mimic the complex scenario described in this article.

scholarly journals Simultaneous Assessment of Endothelial Function, Nitric Oxide Synthase Activity, Nitric Oxide–Mediated Signaling, and Oxidative Stress in Individuals with and without Hypercholesterolemia

2008 ◽  
Vol 54 (2) ◽  
pp. 292-300 ◽  
Author(s):  
Renke Maas ◽  
Edzard Schwedhelm ◽  
Lydia Kahl ◽  
Huige Li ◽  
Ralf Benndorf ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Endothelial Function ◽  
Urinary Excretion ◽  
Indirect Evidence ◽  
No Oxidation ◽  
Whole Body ◽  
Gas Chromatography Mass Spectrometry ◽  
Synthesis Rate ◽  
No Production

Abstract Background: Endothelial function is impaired in hypercholesterolemia and atherosclerosis. Based on mostly indirect evidence, this impairment is attributed to reduced synthesis or impaired biological activity of endothelium-derived nitric oxide (NO). It was the aim of this study to directly estimate and compare whole-body NO production in normo- and hypercholesterolemia by applying a nonradioactive stable isotope dilution technique in vivo. Methods: We enrolled 12 normocholesterolemic and 24 hypercholesterolemic volunteers who were all clinically healthy. To assess whole-body NO synthesis, we intravenously administered l-[guanidino-(15N2)]-arginine and determined the urinary excretion of 15N-labeled nitrate, the specific end product of NO oxidation in humans, by use of gas chromatography-mass spectrometry. In addition, we measured flow-mediated vasodilation (FMD) of the brachial artery, expression of endothelial NOS (eNOS) in platelets, plasma concentration of the endogenous NOS inhibitor asymmetric dimethylarginine (ADMA), and urinary excretion of 8-isoprostaglandin F2α (8-iso-PGF2α). Results: After infusion of l-[guanidino-(15N2)]-arginine, cumulative excretion of 15N-labeled-nitrate during 48 h was 40% [95% CI 15%–66%] lower in hypercholesterolemic than normocholesterolemic volunteers [mean 9.2 (SE 0.8) μmol vs 15.4 (2.3) μmol/l, P = 0.003]. FMD was on average 36% [4%–67%] lower in hypercholesterolemic than normocholesterolemic volunteers [6.3 (4.0)% vs 9.4 (4.6)%, P = 0.027]. Normalized expression of NOS protein in platelets was also significantly lower in hypercholesterolemic volunteers, whereas there were no significant differences in plasma ADMA concentration or urinary excretion of 8-iso-PGF2α between the 2 groups. Conclusions: This study provides direct evidence for a decreased whole body NO synthesis rate in healthy people with hypercholesterolemia.

scholarly journals In Vitro Study of Nitric Oxide Metabolites Effects on Human Hydatid ofEchinococcus granulosus

2009 ◽  
Vol 2009 ◽  
pp. 1-7 ◽  
Author(s):  
Razika Zeghir-Bouteldja ◽  
Manel Amri ◽  
Saliha Aitaissa ◽  
Samia Bouaziz ◽  
Dalila Mezioug ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Hydatid Cyst ◽  
Echinococcus Granulosus ◽  
In Vitro Study ◽  
No Production ◽  
In Vitro Effects ◽  
Nitric Oxide Metabolites

Hydatidosis is characterized by the long-term coexistence of larvaEchinococcus granulosusand its host without effective rejection. Previous studies demonstrated nitric oxide (NO) production (in vivo and in vitro) during hydatidosis. In this study, we investigated the direct in vitro effects of NO species: nitrite (NO2−), nitrate (NO3−) and peroxynitrite (ONOO−) on protoscolices (PSCs) viability and hydatid cyst layers integrity for 24 hours and 48 hours. Our results showed protoscolicidal activity ofNO2−andONOO−24 hours and 3 hours after treatment with 320 μM and 80 μM respectively. Degenerative effects were observed on germinal and laminated layers. The comparison of the in vitro effects of NO species on the PSCs viability indicated thatONOO−is more cytotoxic thanNO2−. In contrast,NO3−has no effect. These results suggest possible involvement ofNO2−andONOO−in antihydatic action and point the efficacy of these metabolites as scolicidal agents.

scholarly journals Considerations to Model Heart Disease in Women with Preeclampsia and Cardiovascular Disease

2021 ◽  
Author(s):  
Clara Liu Chung Ming ◽  
Kimberly Sesperez ◽  
Eitan Ben-Sefer ◽  
David Arpon ◽  
Kristine McGrath ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Cardiovascular Disease ◽  
Ex Vivo ◽  
Myocardial Damage ◽  
Cardiovascular Disorder ◽  
Model Systems ◽  
Ex Vivo Model ◽  
Disease Manifestation

Preeclampsia is a multifactorial cardiovascular disorder diagnosed after 20 weeks of gestation that is the leading cause of death for both mothers and babies in pregnancy. The pathophysiology remains poorly understood due to variability and unpredictability of disease manifestation when studied in animal models. After preeclampsia, both mothers and offspring have a higher risk of cardiovascular disease (CVD) including myocardial infarction or heart attack and heart failure (HF). Myocardial infarction is an acute myocardial damage that can be treated through reperfusion, however, that therapeutic approach leads to ischemic/reperfusion injury (IRI) often leading to HF. In this review, we compared the current in vivo, in vitro and ex vivo model systems used to study preeclampsia, IRI and HF. Future studies aiming at evaluating CVD in preeclampsia patients could benefit from novel models that better mimic the complex scenario described in this article.

scholarly journals The MEMIC: An ex vivo system to model the complexity of the tumor microenvironment

2021 ◽  
Author(s):  
Libuše Janská ◽  
Libi Anandi ◽  
Nell C. Kirchberger ◽  
Zoran S. Marinkovic ◽  
Logan T. Schachtner ◽  
...  
Keyword(s):  
Tumor Microenvironment ◽  
Tumor Cells ◽  
Ex Vivo ◽  
Tumor Stroma ◽  
Stem Cell Differentiation ◽  
Blood Stream ◽  
Direct Access ◽  
Ex Vivo Model

There is an urgent need for accurate, scalable, and cost-efficient experimental systems to model the complexity of the tumor microenvironment. Here, we detail how to fabricate and use the Metabolic Microenvironment Chamber (MEMIC) – a 3D-printed ex vivo model of intratumoral heterogeneity. A major driver of the cellular and molecular diversity in tumors is the accessibility to the blood stream that provides key resources such as oxygen and nutrients. While some tumor cells have direct access to these resources, many others must survive under progressively more ischemic environments as they reside further from the vasculature. The MEMIC is designed to simulate the differential access to nutrients and allows co-culturing different cell types, such as tumor and immune cells. This system is optimized for live imaging and other microscopy-based approaches, and it is a powerful tool to study tumor features such as the effect of nutrient scarcity on tumor-stroma interactions. Due to its adaptable design and full experimental control, the MEMIC provide insights into the tumor microenvironment that would be difficult to obtain via other methods. As a proof of principle, we show that cells sense gradual changes in metabolite concentration resulting in multicellular spatial patterns of signal activation and cell proliferation. To illustrate the ease of studying cell-cell interactions in the MEMIC, we show that ischemic macrophages reduce epithelial features in neighboring tumor cells. We propose the MEMIC as a complement to standard in vitro and in vivo experiments, diversifying the tools available to accurately model, perturb, and monitor the tumor microenvironment, as well as to understand how extracellular metabolites affect other processes such as wound healing and stem cell differentiation.

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