Abstract 13295: Novel Experimental Therapeutics for COVID-19 Derived From a Nitric Oxide Donor

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
John F Schmedtje ◽  
Zahra Assar
Keyword(s):  
Nitric Oxide ◽  
Protein Interactions ◽  
In Silico ◽  
Vascular Endothelial Cells ◽  
Specific Binding ◽  
Nitric Oxide Donor ◽  
Isosorbide Mononitrate ◽  
Vascular Endothelial ◽  
No Donor ◽  
Glide Docking

Urea transport protein B, the product of the gene SLC14A1 , facilitates transport of urea, water and urea analogues across cell membranes. SLC14A1 mRNA is overexpressed in human vascular endothelial cells in culture under hypoxic (1% oxygen) conditions compared with normoxia. This leads to transport of urea out of the endothelial cell and likely contributes to the reduction in eNOS (endothelial nitric oxide synthase) pathway activity in hypoxia. NO has antiviral activity. Novel compounds were developed by binding a urea-like moiety to the backbone of the generic agent isosorbide mononitrate, a well-known NO donor, to combat vascular endothelial dysfunction in COVID-19, a disease characterized by systemic hypoxia and inflammation due to SARS-CoV-2 infection. A study of drug-protein interactions was undertaken using in silico modelling. Novel compounds were studied against 9 key SARS-CoV-2 targets using Maestro, Schrödinger Suite software (Glide docking). Docking scores and intermolecular interactions within the target’s key binding amino acid residues were studied to compare investigational compounds and known antivirals. Several novel agents tested had a better Glide Score (a prediction of ligand affinity) against the papain-like protease (PL pro ) of SARS-CoV-2 compared with known antiviral drugs. PL pro is considered to be a primary target for therapeutic inhibition of the SARS viruses. The candidate compounds CR-305, CR-607, CR-510 and CR-605 were all superior to Remdesivir, GS-441524, Lopinavir, Boceprevir, and Ribavirin. Given the known direct antiviral action of NO and evidence of specific binding of these compounds to the PL pro of SARS-CoV-2 based on the in silico results, we conclude there is a high likelihood these novel compounds will prove to be of therapeutic value against COVID-19. CR-305 appears to have a higher affinity to SARS-CoV-2 than other antivirals as it sits firmly in the PL pro catalytic pocket and makes the most of key interactions with the catalytic pocket residues: Gly163, Asp164, Gln271 and Tyr264. These data call for a new focus on these novel antiviral agents as they appear to bind with an increased avidity to PL pro (compared with other known antivirals) while targeting delivery of NO to the SARS-CoV-2 virus in COVID-19.

scholarly journals Immobilized DNA aptamers used as potent attractors for vascular endothelial cell: in vitro study of female rat

2020 ◽  
Vol 40 (1) ◽  
Author(s):  
Jung-Joon Cha ◽  
Hoyeon Lee ◽  
Miyoung Kim ◽  
Juyoung Kang ◽  
Hanlim Song ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Vascular Function ◽  
Therapeutic Potential ◽  
Vascular Endothelial Cells ◽  
Specific Binding ◽  
Vascular Endothelial Cell ◽  
Dna Aptamers ◽  
Female Rat ◽  
Vascular Endothelial

Abstract Vascular endothelial cells are essential to vascular function and maintenance. Dysfunction of these cells can lead to the development of cardiovascular disease or contribute to tumorigenesis. As such, the therapeutic modulation and monitoring of vascular endothelial cells are of significant clinical interest, and several endothelial-specific ligands have been developed for drug delivery and the monitoring of endothelial function. However, the application of these ligands has been limited by their high cost and tendency to induce immune responses, highlighting a need for alternate methods of targeting vascular endothelial cells. In the present study, we explore the therapeutic potential of DNA aptamers. Using cell-SELEX technology, we identified two aptamers with specific binding affinity for vascular endothelial cells and propose that these molecules show potential for use as new ligands for drug and biomarker research concerning vascular endothelial cells.

Abstract 153: Bile Acid Receptor TGR5 Agonism Represents Anti-inflammatory Effects via Stimulating Nitric Oxide Production in Vascular Endothelial Cells

2012 ◽  
Vol 32 (suppl_1) ◽  
Author(s):  
Taiki Kida ◽  
Yoshiki Tsubosaka ◽  
Masatoshi Hori ◽  
Hiroshi Ozaki ◽  
Takahisa Murata
Keyword(s):  
Nitric Oxide ◽  
Endothelial Cells ◽  
Bile Acids ◽  
Inflammatory Responses ◽  
Vascular Endothelial Cells ◽  
Lithocholic Acid ◽  
Signal Pathways ◽  
No Production ◽  
Vascular Endothelial ◽  
Anti Inflammatory

Objective TGR5, a membrane-bound, G-protein-coupled receptor for bile acids, is known to be involved in regulation of energy homeostasis and inflammation. However, little is known about the function of TGR5 in vascular endothelial cells. In the present study, we examined whether TGR5 agonism represents anti-inflammatory effects in vascular endothelial cells focusing on nitric oxide (NO) production. Methods and Results In human umbilical vein endothelial cells (HUVECs), treatment with taurolithocholic acid (TLCA), which has the highest affinity to TGR5 among various bile acids, significantly reduced tumor necrosis factor (TNF)-α-induced vascular cell adhesion molecule (VCAM)-1 protein expression and adhesion of human monocytes, U937. These effects were abrogated by a NO synthase (NOS) inhibitor, N G -Monomethyl-L-arginine (L-NMMA). In bovine aortic endothelial cells (BAECs), treatment with TLCA as well as lithocholic acid, which also has high affinity to TGR5, significantly increased the NO production. In contrast, deoxycholic acid and chenodeoxycholic acid, which possess low affinity to TGR5, did not affect the NO production. Gene depletion of TGR5 by siRNA transfection abolished TLCA-induced NO production in BAECs. TLCA-induced NO production was also observed in HUVECs measured as intracellular cGMP accumulation. We next investigated the signal pathways responsible for the TLCA-induced NO production in endothelial cells. Treatment with TLCA increased endothelial NOS (eNOS) ser1177 phosphorylation in HUVECs. This response was accompanied by increased Akt ser473 phosphorylation and intracellular Ca 2+ ([Ca 2+ ] i ). Treatment with phosphoinositide 3-kinase (PI3K) inhibitor, LY294002, or blockade of calcium channel with La 3+ , significantly decreased TLCA-induced eNOS ser1177 phosphorylation and subsequent NO production. Conclusion These results indicate that TGR5 agonism can mediate anti-inflammatory responses by suppressing VCAM-1 expression and monocytes adhesion to endothelial cells. This function is dependent on NO production via Akt activation and [Ca 2+ ] i increase.

Abstract 5456: Vascular Endothelial Cells Endothelin-1 Deficiency Decreased Vascular Protection in Atherosclerosis Mouse Model

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Dyah Wulan Anggrahini ◽  
Noriaki Emoto ◽  
Kazuhiko Nakayama ◽  
Bambang Widyantoro ◽  
Kazuya Miyagawa ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Endothelial Cells ◽  
Vessel Wall ◽  
Vascular Endothelial Cells ◽  
Mrna Level ◽  
Vascular Wall ◽  
Protective Mechanism ◽  
Vascular Endothelial ◽  
Vascular Protection ◽  
Plaque Instability

Endothelium plays important role in protective mechanism of vascular wall. The balance between endothelin-1 (ET-1) and nitric oxide provide endothelial barrier to lipoprotein retain and macrophage recruitment. In contrasts, ET-1 is also a strong vasoconstrictor. In this study, we aim to determine the role of vascular endothelial cells-derived ET-1 in the development of atherosclerosis. For that purpose, we crossbred Vascular Endothelial Cells-specific ET-1 Knockout (VEETKO) mice to ApoEKO mice. ApoE/VEET-DKO exhibited significantly lower ET-1 plasma and mRNA level as compared to ApoEKO mice. No significant differences of blood pressure, plasma cholesterol or lipid profiles were observed in both mice. Surprisingly, after 8 weeks of western diet, we found that the atherosclerotic lesion was exaggerated in the aortic sinus and brachiochepalic artery of ApoE/VEET-DKO mice (n=7) as compared to those of ApoEKO mice (n=7) (ratio/vessel wall, 0.93±0.13vs.0.49±0.09, p<0.05). We further showed the increase in macrophage plaque content and peritoneal macrophage recruitment in DKO mice. To understand the mechanism of vascular protection, we found lower eNOS mRNA level in DKO mice despite only lower tendency of ETB receptor expression. Functionally, the mice lacking ET-1 in endothelial cells showed impaired NO-mediated endothelial function. Decreased vascular protection further led to increase plaque instability in DKO mice. Here we showed that plaque of DKO mice was more lipid enrich as compared to that of ApoEKO (ratio/lesion, 0.56±0.03vs.0.42±0.04, p<0.05). Moreover, lack of ET-1 significantly reduced matrix synthesis following lower SMCs accumulation in the lesion (ratio/vessel wall, 0.28±0.06vs.0.57±0.08, p<0.05), which was mediated by TGFβ. Interestingly, despite similar advance-typed lesion formed, 15% of DKO mice exhibited plaque hemorrhage in brachiochepalic artery. In conclusion, we demonstrated the increase in atherosclerosis and plaque instability in our model. This further suggests that ET-1 produced from vascular endothelial cells is required for protective mechanism in vascular wall in balance with nitric oxide production. Our data imply for the careful monitoring in the use of ET receptor antagonist in clinical setting.

Skeletal muscle force and actomyosin ATPase activity reduced by nitric oxide donor

1997 ◽  
Vol 83 (4) ◽  
pp. 1326-1332 ◽  
Author(s):  
William J. Perkins ◽  
Young-Soo Han ◽  
Gary C. Sieck
Keyword(s):  
Nitric Oxide ◽  
Mechanical Properties ◽  
Atpase Activity ◽  
Muscle Force ◽  
Isometric Force ◽  
Nitric Oxide Donor ◽  
No Donor ◽  
Single Fibers ◽  
Actomyosin Atpase ◽  
Cross Bridge

Perkins, William J., Young-Soo Han, and Gary C. Sieck.Skeletal muscle force and actomyosin ATPase activity reduced by nitric oxide donor. J. Appl. Physiol.83(4): 1326–1332, 1997.—Nitric oxide (NO) may exert direct effects on actin-myosin cross-bridge cycling by modulating critical thiols on the myosin head. In the present study, the effects of the NO donor sodium nitroprusside (SNP; 100 μM to 10 mM) on mechanical properties and actomyosin adenosinetriphosphatase (ATPase) activity of single permeabilized muscle fibers from the rabbit psoas muscle were determined. The effects of N-ethylmaleimide (NEM; 5–250 μM), a thiol-specific alkylating reagent, on mechanical properties of single fibers were also evaluated. Both NEM (≥25 μM) and SNP (≥1 mM) significantly inhibited isometric force and actomyosin ATPase activity. The unloaded shortening velocity of SNP-treated single fibers was decreased, but to a lesser extent, suggesting that SNP effects on isometric force and actomyosin ATPase were largely due to decreased cross-bridge recruitment. The calcium sensitivity of SNP-treated single fibers was also decreased. The effects of SNP, but not NEM, on force and actomyosin ATPase activity were reversed by treatment with 10 mMdl-dithiothreitol, a thiol-reducing agent. We conclude that the NO donor SNP inhibits contractile function caused by reversible oxidation of contractile protein thiols.

scholarly journals Dopamine in the ink defence system of Sepia officinalis: biosynthesis, vesicular compartmentation in mature ink gland cells, nitric oxide (NO)/cGMP-induced depletion and fate in secreted ink1

2004 ◽  
Vol 378 (3) ◽  
pp. 785-791 ◽  
Author(s):  
Gabriella FIORE ◽  
Annarita POLI ◽  
Anna Di COSMO ◽  
Marco d'ISCHIA ◽  
Anna PALUMBO
Keyword(s):  
Nitric Oxide ◽  
Tyrosine Hydroxylase ◽  
Physical Adsorption ◽  
Signalling Pathway ◽  
Nitric Oxide Donor ◽  
Sepia Officinalis ◽  
Release Process ◽  
No Donor ◽  
Cgmp Signalling ◽  
Incubation Experiments

The biosynthesis, localization and fate of catecholamines in the ink gland of the cuttlefish Sepia officinalis were investigated by combined biochemical and immunohistocytochemical methodologies. HPLC analysis of crude ink gland extracts indicated the presence of dopa (2.18±0.82 nmol/mg of protein) and DA (dopamine, 0.06±0.02 nmol/mg of protein), but no detectable noradrenaline or adrenaline. DA was shown to derive from l-tyrosine, according to experiments performed by incubating intact ink glands with [l-14C]tyrosine. The biosynthetic process involves a tyrosine hydroxylase and a dopa decarboxylase pathway and is independent of tyrosinase. The tyrosine hydroxylase activity was detected under conditions of tyrosinase suppression in the cytosolic fraction, but not in the melanosomal fraction, of ink gland extracts, and the presence of the enzyme was confirmed by Western-blot analysis. Dopa and DA were found to be released from the ink glands by processes controlled through the NMDA-nitric oxide-cGMP (where NMDA stands for N-methyl-d-aspartate) signalling pathway, as apparent from incubation experiments performed with [l-14C]tyrosine in the presence of NMDA, diethylamine NONOate (diethylamine diazeniumdiolate), a nitric oxide donor, 8-bromo-cGMP or a guanylyl cyclase inhibitor. Immunohistochemical results coupled with electron microscopy indicated that DA was concentrated in vesicles specifically localized in the mature melanin-producing cells of the ink gland proximal to the lumen and separated from the melanin-containing melanosomes. NMDA receptor stimulation or exposure to an NO donor caused a marked loss of DA immunoreactivity in mature cells, consistent with a release process. In the lumen of the ink gland, where mature exhausted cells pour their contents, DA immunoreactivity was found to be associated with the melanin granules, due apparently to physical adsorption. Overall, these results point to DA as a marker of cell maturation in Sepia ink gland subject to release by the NO/cGMP signalling pathway, and disclose apparently overlooked DA–melanin interactions in secreted ink of possible relevance to the defence mechanism.

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