scholarly journals Exposure to nitric oxide drives transition to resuscitation-promoting factor-dependency in mycobacteria

2021 ◽  
Author(s):  
Sarah M Glenn ◽  
Brindha Gap-Gaupool ◽  
Simon J Waddell ◽  
Joanna Bacon ◽  
Marialuisa Crosatti ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Transcriptional Profiling ◽  
Diagnostic Tools ◽  
Flow Cytometry Analysis ◽  
Liquid Media ◽  
No Donor ◽  
Major Barrier ◽  
Solid Media

Rationale: Mycobacterium tuberculosis (Mtb) has a devastating impact on global health. Mtb is the causative agent of human pulmonary tuberculosis (TB), which claims 1.4 million lives per annum. During infection, differentially culturable bacilli (DCB) that fail to produce colonies on solid media but grow in liquid media supplemented with resuscitation-promoting factor (Rpf) proteins are formed. These Rpf-dependent mycobacteria are a major barrier to developing improved TB treatments and diagnostic tools. Objectives: To evaluate whether exposure to nitric oxide (NO), a prominent host defense molecule, drives the generation of Rpf-dependent DCB. Methods: A new NO donor (ND) for sustained NO release was synthesized. Growth assays, flow cytometry analysis, and global transcriptional profiling, were used to characterize ND-treated Mtb and Mycobacterium bovis BCG in vitro. Mycobacterial DCB phenotypes were also investigated after infection of THP-1 human cells, which were activated with retinoic acid and vitamin D3. Measurements and Main Results: DCB were generated after exposure to ND and during infection of activated THP-1 cells. Resuscitation of these DCB was severely impaired by a specific Rpf inhibitor (3-nitro-4-thiocyanato-phenyl)-phenyl-methanone. Global transcriptomic analyses revealed the down-regulation of three (rpfA, rpfB and rpfE) of the five genes coding for Rpf proteins. Conclusion: A new model for investigation of the transition of Mtb into an Rpf-dependent differentially culturable state is presented. The system reveals mechanistic insights into the generation of Rpf-dependent Mtb during TB disease and demonstrates the role of NO in this process.

scholarly journals Nitric oxide synthase acutely regulates progesterone production by in vitro cultured rabbit corpora lutea

1999 ◽  
Vol 160 (2) ◽  
pp. 275-283 ◽  
Author(s):  
A Gobbetti ◽  
C Boiti ◽  
C Canali ◽  
M Zerani
Keyword(s):  
Nitric Oxide ◽  
In Vitro Release ◽  
Inhibitory Effect ◽  
Corpora Lutea ◽  
No Donor ◽  
Nos Inhibitor ◽  
Oxide Synthase ◽  
Vitro Release

We examined the presence and the regulation of nitric oxide (NO) synthase (NOS) using in vitro cultured corpora lutea (CL) obtained from rabbits at days 4 and 9 of pseudopregnancy. The role of NO and NOS on steroidogenesis was also investigated using the same CL preparations after short-term incubations (30 min and 2 h) with the NO donor, sodium nitroprusside (NP), the NOS inhibitor, Nomega-nitro-l-arginine methyl ester (l-NAME) and prostaglandin (PG) F-2alpha. The basal NOS activity was greater in CL at day 4 than at day 9, and was also differently modulated by PGF-2alpha, depending on the age of the CL. The addition of PGF-2alpha to day 4 CL had no effect, but PGF-2alpha on day 9 caused a threefold increase in NOS activity. NP caused a two- to fivefold decrease in release of progesterone from CL of both ages, and this inhibitory effect on steroidogenesis was reversed by l-NAME. All treatments failed to modify basal androgens and 17beta-oestradiol was not detectable in either control or treated CL. These results suggest that NO is effectively involved in the regulation process of steroidogenesis, independently of 17beta-oestradiol. PGF-2alpha had no effect on day 4, but induced luteolysis on day 9, by reducing progesterone (P</=0. 01) to about 18% of control. The luteolytic action of PGF-2alpha was completely reversed by co-incubation with l-NAME, thus supporting the hypothesis that luteolysis is mediated by NO. The addition of NP or l-NAME did not modify the in vitro release of PGF-2alpha. We hypothesised that PGF-2alpha upregulates NOS activity and, consequently, the production of NO, which acutely inhibits progesterone release from day 9 CL of pseudopregnant rabbits.

Role of BKCa Channels in Cephalic Vasodilation Induced by CGRP, NO and Transcranial Electrical Stimulation In The Rat

Cephalalgia ◽  
2007 ◽  
Vol 27 (10) ◽  
pp. 1120-1127 ◽  
Author(s):  
A Gozalov ◽  
I Jansen-Olesen ◽  
D Klaerke ◽  
J Olesen
Keyword(s):  
Nitric Oxide ◽  
Electrical Stimulation ◽  
Selective Inhibitor ◽  
Transcranial Electrical Stimulation ◽  
Bkca Channels ◽  
No Donor ◽  
Calcitonin Gene

Both calcitonin gene-related peptide (CGRP) and nitric oxide (NO) are potent vasodilators that have been shown to induce headache in migraine patients. Their antagonists are effective in the treatment of migraine attacks. In the present study, we hypothesize that vasodilation induced by the NO donor glyceryltrinitrate (GTN) or by CGRP is partially mediated via large conductance calcium-activated potassium (BKCa) channels. The effects of the BKCa channel selective inhibitor iberiotoxin on dural and pial vasodilation induced by CGRP, GTN and endogenously released CGRP by transcranial electrical stimulation (TES) were examined. Iberiotoxin significantly attenuated GTN-induced dural and pial artery dilation in vivo and in vitro, but had no effect on vasodilation induced by CGRP and TES. Our results show that GTN- but not CGRP-induced dural and pial vasodilation involves opening of BKCa channels in rat.

scholarly journals Flow Cytometric Evaluation of Human Neutrophil Apoptosis During Nitric Oxide Generation In Vitro: The Role of Exogenous Antioxidants

2005 ◽  
Vol 2005 (2) ◽  
pp. 81-87 ◽  
Author(s):  
Zofia Sulowska ◽  
Ewa Majewska ◽  
Magdalena Klink ◽  
Malgorzata Banasik ◽  
Henryk Tchórzewski
Keyword(s):  
Nitric Oxide ◽  
Human Neutrophil ◽  
Flow Cytometric Analysis ◽  
Human Neutrophils ◽  
Neutrophil Apoptosis ◽  
No Donor ◽  
No Donors ◽  
Flow Cytometric

Among numerous inflammatory mediators a nitric oxide molecule is supposed to be important in the modulation of neutrophil survival in vivo and in vitro. The effect of exogenous supply of NO donors such as SNP, SIN-1, and GEA-3162 on the course of human neutrophil apoptosis and the role of extracellular antioxidants in this process was investigated. Isolated from peripheral blood, neutrophils were cultured in the presence or absence of NO donor compounds and antioxidants for 8, 12, and20hours. Apoptosis of neutrophils was determined in vitro by flow cytometric analysis of cellular DNA content and Annexin V protein binding to the cell surface. Exposure of human neutrophils to GEA-3162 and SIN-1 significantly accelerates and enhances their apoptosis in vitro in a time-dependent fashion. In the presence of SNP, intensification of apoptosis has not been revealed until12hours after the culture. The inhibition of GEA-3162- and SIN-1-mediated neutrophil apoptosis by superoxide dismutase (SOD) but not by catalase (CAT) was observed. Our results show that SOD and CAT can protect neutrophils against NO-donors-induced apoptosis and suggest that the interaction of NO and oxygen metabolites signals may determine the destructive or protective role of NO donor compounds during apoptotic neutrophil death.

scholarly journals Nitric Oxide in the Control of the in vitro Proliferation and Differentiation of Human Hematopoietic Stem and Progenitor Cells

2021 ◽  
Vol 8 ◽  
Author(s):  
Julia Hümmer ◽  
Saskia Kraus ◽  
Katharina Brändle ◽  
Cornelia Lee-Thedieck
Keyword(s):  
Nitric Oxide ◽  
Cellular Therapy ◽  
Blood Stream ◽  
Guanosine Monophosphate ◽  
In Vitro Proliferation ◽  
No Donor ◽  
Hematopoietic Stem

Hematopoietic stem and progenitor cell (HSPC) transplantation is the best-studied cellular therapy and successful in vitro control of HSPCs has wide clinical implications. Nitric oxide (NO) is a central signaling molecule in vivo and has been implicated in HSPC mobilization to the blood stream in mice. The influence of NO on HSPC behavior in vitro is, however, largely obscure due to the variety of employed cell types, NO administration systems, and used concentration ranges in the literature. Additionally, most studies are based on murine cells, which do not necessarily mimic human HSPC behavior. Thus, the aim of the present study was the systematic, concentration-dependent evaluation of NO-mediated effects on human HSPC behavior in vitro. By culture in the presence of the long-term NO donor diethylenetriamine/nitric oxide adduct (DETA/NO) in a nontoxic concentration window, a biphasic role of NO in the regulation of HSPC behavior was identified: Low DETA/NO concentrations activated classical NO signaling, identified via increased intracellular cyclic guanosine monophosphate (cGMP) levels and proteinkinases G (PKG)-dependent vasodilator-stimulated phosphoprotein (VASP) phosphorylation and mediated a pro-proliferative response of HSPCs. In contrast, elevated NO concentrations slowed cell proliferation and induced HSPC differentiation. At high concentrations, s-nitrosylation levels were elevated, and myeloid differentiation was increased at the expense of lymphoid progenitors. Together, these findings hint at a central role of NO in regulating human HSPC behavior and stress the importance and the potential of the use of adequate NO concentrations for in vitro cultures of HSPCs, with possible implications for clinical application of in vitro expanded or differentiated HSPCs for cellular therapies.

scholarly journals Florigen governs shoot regeneration

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yaarit Kutsher ◽  
Michal Fisler ◽  
Adi Faigenboim ◽  
Moshe Reuveni
Keyword(s):  
Nitric Oxide ◽  
Shoot Regeneration ◽  
Ectopic Expression ◽  
Flowering Plants ◽  
Regeneration Capacity ◽  
No Donor ◽  
Tobacco Leaves ◽  
Age Related ◽  
Delayed Flowering

AbstractIt is widely known that during the reproductive stage (flowering), plants do not root well. Most protocols of shoot regeneration in plants utilize juvenile tissue. Adding these two realities together encouraged us to study the role of florigen in shoot regeneration. Mature tobacco tissue that expresses the endogenous tobacco florigen mRNA regenerates poorly, while juvenile tissue that does not express the florigen regenerates shoots well. Inhibition of Nitric Oxide (NO) synthesis reduced shoot regeneration as well as promoted flowering and increased tobacco florigen level. In contrast, the addition of NO (by way of NO donor) to the tissue increased regeneration, delayed flowering, reduced tobacco florigen mRNA. Ectopic expression of florigen genes in tobacco or tomato decreased regeneration capacity significantly. Overexpression pear PcFT2 gene increased regeneration capacity. During regeneration, florigen mRNA was not changed. We conclude that florigen presence in mature tobacco leaves reduces roots and shoots regeneration and is the possible reason for the age-related decrease in regeneration capacity.

scholarly journals Phaseolin Attenuates Lipopolysaccharide-Induced Inflammation in RAW 264.7 Cells and Zebrafish

Biomedicines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 420
Author(s):  
Su-Jung Hwang ◽  
Ye-Seul Song ◽  
Hyo-Jong Lee
Keyword(s):  
Nitric Oxide ◽  
Nuclear Translocation ◽  
Raw 264.7 Cells ◽  
Network Pharmacology ◽  
Raw 264.7 ◽  
Dependent Manner ◽  
Bioactive Constituents

Kushen (Radix Sophorae flavescentis) is used to treat ulcerative colitis, tumors, and pruritus. Recently, phaseolin, formononetin, matrine, luteolin, and quercetin, through a network pharmacology approach, were tentatively identified as five bioactive constituents responsible for the anti-inflammatory effects of S. flavescentis. However, the role of phaseolin (one of the primary components of S. flavescentis) in the direct regulation of inflammation and inflammatory processes is not well known. In this study, the beneficial role of phaseolin against inflammation was explored in lipopolysaccharide (LPS)-induced inflammation models of RAW 264.7 macrophages and zebrafish larvae. Phaseolin inhibited LPS-mediated production of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS), without affecting cell viability. In addition, phaseolin suppressed pro-inflammatory mediators such as cyclooxygenase 2 (COX-2), interleukin-1β (IL-1β), tumor necrosis factor α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), and interleukin-6 (IL-6) in a dose-dependent manner. Furthermore, phaseolin reduced matrix metalloproteinase (MMP) activity as well as macrophage adhesion in vitro and the recruitment of leukocytes in vivo by downregulating Ninjurin 1 (Ninj1), an adhesion molecule. Finally, phaseolin inhibited the nuclear translocation of nuclear factor-kappa B (NF-κB). In view of the above, our results suggest that phaseolin could be a potential therapeutic candidate for the management of inflammation.

scholarly journals Novel Insights on the Role of Nitric Oxide in the Ovary: A Review of the Literature

2021 ◽  
Vol 18 (3) ◽  
pp. 980
Author(s):  
Maria Cristina Budani ◽  
Gian Mario Tiboni
Keyword(s):  
Nitric Oxide ◽  
In Vivo Studies ◽  
Published Data ◽  
Vitro Fertilization ◽  
Peripheral Neurons ◽  
Relevant Role ◽  
Oocyte Meiotic Maturation

Nitric oxide (NO) is formed during the oxidation of L-arginine to L-citrulline by the action of multiple isoenzymes of NO synthase (NOS): neuronal NOS (nNOS), endotelial NOS (eNOS), and inducible NOS (iNOS). NO plays a relevant role in the vascular endothelium, in central and peripheral neurons, and in immunity and inflammatory systems. In addition, several authors showed a consistent contribution of NO to different aspects of the reproductive physiology. The aim of the present review is to analyse the published data on the role of NO within the ovary. It has been demonstrated that the multiple isoenzymes of NOS are expressed and localized in the ovary of different species. More to the point, a consistent role was ascribed to NO in the processes of steroidogenesis, folliculogenesis, and oocyte meiotic maturation in in vitro and in vivo studies using animal models. Unfortunately, there are few nitric oxide data for humans; there are preliminary data on the implication of nitric oxide for oocyte/embryo quality and in-vitro fertilization/embryo transfer (IVF/ET) parameters. NO plays a remarkable role in the ovary, but more investigation is needed, in particular in the context of human ovarian physiology.

Nitric Oxide-Donating Derivatives of Chrysin Stimulate Angiogenesis and Upregulating VEGF Production

2011 ◽  
Vol 340 ◽  
pp. 363-368 ◽  
Author(s):  
Xiao Qing Zou ◽  
Yong Lan Ding ◽  
Sheng Ming Peng ◽  
Chang Ping Hu ◽  
Han Wu Deng ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Endothelial Cells ◽  
Therapeutic Option ◽  
Therapeutic Angiogenesis ◽  
Vegf Mrna ◽  
No Donor ◽  
Endothelial Migration ◽  
Nitric Oxide Releasing ◽  
Derivatives Of

Angiogenesis, the development of new capillaries from pre-existing vessels, requires the coordinate activation of endothelial cells, which migrate and proliferate to form functional vessels. Endothelial dysfunction and decreased nitric oxide bioavailability may underscore the impairment of angiogenesis. As such, the delivery of exogenous NO is an attractive therapeutic option that has been used to therapeutic angiogenesis. In this paper, a novel group of hybrid nitric oxide-releasing chrysin derivatives was synthesized. The results indicated that all these chrysin derivatives exhibited promotion of endothelial migration and tubulogenesis in vitro as well as stimulation angiogenesis in vivo.Furthermore, all compounds released NO upon incubation with phosphate buffer at pH 7.4 and enhanced VEGF secretion and VEGF mRNA expression of endothelial cells. These hybrid ester NO donor prodrugs offer a potential drug design concept for the development of therapeutic or preventive agents for angiogenesis deficiency due to ischemic diseases.

scholarly journals A New MAP Kinase Protein Involved in Estradiol-Stimulated Reproduction of the Helminth ParasiteTaenia crassiceps

2010 ◽  
Vol 2010 ◽  
pp. 1-11 ◽  
Author(s):  
Galileo Escobedo ◽  
Gloria Soldevila ◽  
Guadalupe Ortega-Pierres ◽  
Jesús Ramsés Chávez-Ríos ◽  
Karen Nava ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Map Kinases ◽  
Host Cells ◽  
Cross Contamination ◽  
Flow Cytometry Analysis ◽  
Cellular Processes ◽  
17Β Estradiol ◽  
Activation Motif

MAP kinases (MAPK) are involved in the regulation of cellular processes such as reproduction and growth. In parasites, the role of MAPK has been scarcely studied. Here, we describe the participation of an ERK-like protein in estrogen-dependent reproduction of the helminth parasiteTaenia crassiceps. Our results show that 17β-estradiol induces a concentration-dependent increase in the bud number of in vitro cultured cysticerci. If parasites are also incubated in presence of an ERK-inhibitor, the stimulatory effect of estrogen is blocked. The expression of ERK-like mRNA and its corresponding protein was detected in the parasite. The ERK-like protein was over-expressed by all treatments. Nevertheless, a strong induction of phosphorylation of this protein was observed only in response to 17β-estradiol. Cross-contamination by host cells was discarded by flow cytometry analysis. Parasite cells expressing the ERK-like protein were exclusively located at the subtegument tissue by confocal microscopy. Finally, the ERK-like protein was separated by bidimensional electrophoresis and then sequenced, showing the conserved TEY activation motif, typical of all known ERK 1/2 proteins. Our results show that an ERK-like protein is involved in the molecular signalling during the interaction between the host andT. crassiceps, and may be considered as target for anti-helminth drugs design.

scholarly journals Effect of time and vascular pressure on permeability and cyclic nucleotides in ischemic lungs

2000 ◽  
Vol 279 (5) ◽  
pp. H2077-H2084 ◽  
Author(s):  
David B. Pearse ◽  
Patrice M. Becker
Keyword(s):  
Nitric Oxide ◽  
High Pressure ◽  
Reflection Coefficient ◽  
Cyclic Nucleotides ◽  
Fluid Flux ◽  
No Donor ◽  
Independent Mechanism ◽  
Dependent Mechanism ◽  
Intravascular Pressure

We previously found that increased intravascular pressure decreased ischemic lung injury by a nitric oxide (NO)-dependent mechanism (Becker PM, Buchanan W, and Sylvester JT. J Appl Physiol 84: 803–808, 1998). To determine the role of cyclic nucleotides in this response, we measured the reflection coefficient for albumin (ςalb), fluid flux ( J˙), cGMP, and cAMP in ferret lungs subjected to either 45 min (“short”; n = 7) or 180 min (“long”) of ventilated ischemia. Long ischemic lungs had “low” (1–2 mmHg, n = 8) or “high” (7–8 mmHg, n = 6) vascular pressure. Other long low lungs were treated with the NO donor ( Z)-1-[ N-(3-ammoniopropyl)- N-( n-propyl)amino]diazen-1-ium-1,2-diolate (PAPA-NONOate; 5 × 10−4 M, n = 6) or 8-bromo-cGMP (5 × 10−4 M, n = 6). Compared with short ischemia, long low ischemia decreased ςalb (0.23 ± 0.04 vs. 0.73 ± 0.08; P < 0.05) and increased J˙ (1.93 ± 0.26 vs. 0.58 ± 0.22 ml · min−1 · 100 g−1; P < 0.05). High pressure prevented these changes. Lung cGMP decreased by 66% in long compared with short ischemia. Lung cAMP did not change. PAPA-NONOate and 8-bromo-cGMP increased lung cGMP, but only 8-bromo-cGMP decreased permeability. These results suggest that ischemic vascular injury was, in part, mediated by a decrease in cGMP. Increased vascular pressure prevented injury by a cGMP-independent mechanism that could not be mimicked by administration of exogenous NO.

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