scholarly journals NO● Represses the Oxygenation of Arachidonoyl PE by 15LOX/PEBP1: Mechanism and Role in Ferroptosis

2021 ◽  
Vol 22 (10) ◽  
pp. 5253
Author(s):  
Karolina Mikulska-Ruminska ◽  
Tamil S. Anthonymuthu ◽  
Anastasia Levkina ◽  
Indira H. Shrivastava ◽  
Oleksandr O. Kapralov ◽  
...  
Keyword(s):  
In Silico ◽  
Functional Significance ◽  
Catalytic Site ◽  
Saturation Mutagenesis ◽  
M2 Macrophages ◽  
Modeling And Simulations ◽  
Biochemical System ◽  
No Donor ◽  
M1 Macrophages ◽  
Biochemical Model

We recently discovered an anti-ferroptotic mechanism inherent to M1 macrophages whereby high levels of NO● suppressed ferroptosis via inhibition of hydroperoxy-eicosatetraenoyl-phosphatidylethanolamine (HpETE-PE) production by 15-lipoxygenase (15LOX) complexed with PE-binding protein 1 (PEBP1). However, the mechanism of NO● interference with 15LOX/PEBP1 activity remained unclear. Here, we use a biochemical model of recombinant 15LOX-2 complexed with PEBP1, LC-MS redox lipidomics, and structure-based modeling and simulations to uncover the mechanism through which NO● suppresses ETE-PE oxidation. Our study reveals that O2 and NO● use the same entry pores and channels connecting to 15LOX-2 catalytic site, resulting in a competition for the catalytic site. We identified residues that direct O2 and NO● to the catalytic site, as well as those stabilizing the esterified ETE-PE phospholipid tail. The functional significance of these residues is supported by in silico saturation mutagenesis. We detected nitrosylated PE species in a biochemical system consisting of 15LOX-2/PEBP1 and NO● donor and in RAW264.7 M2 macrophages treated with ferroptosis-inducer RSL3 in the presence of NO●, in further support of the ability of NO● to diffuse to, and react at, the 15LOX-2 catalytic site. The results provide first insights into the molecular mechanism of repression of the ferroptotic Hp-ETE-PE production by NO●.

M2 Macrophages but not M1 Macrophages Are Associated with Worst Outcome in Classical Hodgkin Lymphoma

2014 ◽  
Vol 226 (02) ◽  
Author(s):  
M Barros ◽  
P Segges ◽  
G Vera-Lozada ◽  
R Hassan ◽  
G Niedobitek
Keyword(s):  
Hodgkin Lymphoma ◽  
M2 Macrophages ◽  
Classical Hodgkin Lymphoma ◽  
M1 Macrophages

Reparação óssea no implante dental

2020 ◽  
Vol 12 (45) ◽  
pp. 63-66
Author(s):  
Halim Nagem Filho ◽  
Reinaldo Francisco Maia ◽  
Reinaldo Missaka ◽  
Nasser Hussein Fares
Keyword(s):  
Gene Expression ◽  
Titanium Surface ◽  
Close Contact ◽  
The Other ◽  
Main Function ◽  
Indirect Interaction ◽  
M2 Macrophages ◽  
Activated Macrophages ◽  
M1 Macrophages ◽  
High Production

The osseointegration is the stable and functional union between the bone and a titanium surface. A new bone can be found on the surface of the implant about 1 week after its installation; the bone remodeling begins between 6 and 12 weeks and continues throughout life. After the implant insertion, depending on the energy of the surface, the plasma fluid immediately adheres, in close contact with the surface, promoting the adsorption of proteins and inducing the indirect interaction of the cells with the material. Macrophages are cells found in the tissues and originated from bone marrow monocytes. The M1 macrophages orchestrate the phagocytic phase in the inflammatory region and also produce inflammatory cytokines involved with the chronic inflammation and the cleaning of the wound and damaged tissues from bacteria. On the other hand, alternative-activated macrophages (M2) are activated by IL-10, the immune complex. Its main function consists on regulating negatively the inflammation through the secretion of the immunosuppressant IL-10. The M2 macrophages present involvement with the immunosuppression, besides having a low capacity for presenting antigens and high production of cytokines; these can be further divided into M2a, M2b, and M2c, based on the gene expression profile.

α-Glucosidase Inhibition, Antioxidant and Docking Studies of Hydroxycoumarins and their Mono and Bis O-alkylated/acetylated Analogs

2018 ◽  
Vol 15 (2) ◽  
pp. 127-135 ◽  
Author(s):  
Parvesh Singh ◽  
Nomandla Ngcoya ◽  
Ramgopal Mopuri ◽  
Nagaraju Kerru ◽  
Neha Manhas ◽  
...  
Keyword(s):  
In Silico ◽  
Biological Activities ◽  
Wide Spectrum ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Catalytic Site ◽  
Docking Simulations ◽  
In Silico Docking ◽  
Anti Oxidant

Background: Diabetes Mellitus (DM) is a complex metabolic disease illustrated by abnormally high levels of plasma glucose or hyperglycaemia. Accordingly, several α-glucosidase inhibitors have been developed for the treatment of diabetes and other degenerative disorders. While, a coumarin ring has the privilege to represent numerous natural and synthetic compounds with a wide spectrum of biological activities e.g. anti-cancer, anti-HIV, anti-viral, anti-malarial, anti-microbial, anti-convulsant, anti-hypertensive properties. Besides this, coumarins have also shown potential to inhibit α-glucosidase leading to a generation of new promising antidiabetic agents. However, the testing of O-substituted coumarins for α-glucosidase inhibition has evaded the attention of medicinal chemists. Methods: For O-alkylation/acetylation reactions, the hydroxyl coumarins (A-B) initially activated by K2CO3 in dry DMF were reacted with variedly substituted haloalkanes at room temperature under nitrogen. The synthesized compounds were tested for their α-glucosidase (from Saccharomyces cerevisiae) inhibitory activity and anti-oxidant activity using DPPH radical scavenging activity. In silico docking simulations were conducted using CDocker module in DS (Accelrys) to explore the binding modes of the representative compounds in the catalytic site of α-glucosidase. Results: All the coumarin analogues (A1, B1, A2-A10, B2-B8) including their precursors (A-B) were evaluated for their in vitro α-glucosidase inhibition using acarbose as a standard inhibitor. All the mono O-alkylated coumarins (except A1) showed significant (p <0.05) α-glucosidase inhibition relative to the hydroxyl coumarin (A) with IC50 values ranging between 11.084±0.117 to 145.24± 29.22 µg/mL. Compound 7-(benzyloxy)-4, 5-dimethyl-2H-chromen-2-one (A9) bearing a benzyl group (Ph-CH2-) at position 7 showed a remarkable (p <0.05) increase in the activity (IC50 = 11.084±0.117 µg/mL), almost four-fold more than acarbose (IC50 = 40.578±5.999 µg/mL). The introduction of –NO2 group dramatically improved the anti-oxidant activity of coumarin, while the O-alkylation/acetylation decreased the activity. Conclusion: The present study describes the synthesis of functionalized coumarins and their evaluation for α-glucosidase inhibition and antioxidant activity under in vitro conditions. Based on IC50 data, the mono O-alkylated coumarins were observed to be stronger inhibitors of α-glucosidase with respect to their bis O-alkylated analogues. Coumarin (A9) bearing O-benzyloxy group displayed the strongest α-glucosidase inhibition, even higher than the standard inhibitor acarbose. The coumarin (A10) bearing –NO2 group showed the highest anti-oxidant activity amongst the synthesized compounds, almost comparable to the ascorbic acid. Finally, in silico docking simulations revealed the role of hydrogen bonding and hydrophobic forces in locking the compounds in catalytic site of α-glucosidase.

scholarly journals In silico saturation mutagenesis of cancer genes

Nature ◽  
2021 ◽  
Author(s):  
Ferran Muiños ◽  
Francisco Martínez-Jiménez ◽  
Oriol Pich ◽  
Abel Gonzalez-Perez ◽  
Nuria Lopez-Bigas
Keyword(s):  
In Silico ◽  
Saturation Mutagenesis ◽  
Cancer Genes

scholarly journals Efficient In Silico Saturation Mutagenesis of a Member of the Caspase Protease Family

2021 ◽  
Author(s):  
Christoph Öhlknecht ◽  
Sonja Katz ◽  
Christina Kröß ◽  
Bernhard Sprenger ◽  
Petra Engele ◽  
...  
Keyword(s):  
In Silico ◽  
Saturation Mutagenesis

scholarly journals Potential of NO donor furoxan as SARS-CoV-2 main protease (Mpro) inhibitors: in silico analysis

2020 ◽  
pp. 1-15 ◽  
Author(s):  
Abdullah G. Al-Sehemi ◽  
Mehboobali Pannipara ◽  
Rishikesh S. Parulekar ◽  
Omkar Patil ◽  
Prafulla B. Choudhari ◽  
...  
Keyword(s):  
In Silico ◽  
In Silico Analysis ◽  
No Donor ◽  
Main Protease ◽  
Silico Analysis

scholarly journals Acid Sphingomyelinase Controls Early Phases of Skeletal Muscle Regeneration by Shaping the Macrophage Phenotype

Cells ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 3028
Author(s):  
Paulina Roux-Biejat ◽  
Marco Coazzoli ◽  
Pasquale Marrazzo ◽  
Silvia Zecchini ◽  
Ilaria Di Renzo ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Satellite Cells ◽  
Muscle Regeneration ◽  
Acid Sphingomyelinase ◽  
Skeletal Muscle Regeneration ◽  
Sphingolipid Metabolism ◽  
M2 Macrophages ◽  
Macrophage Phenotype ◽  
M1 Macrophages ◽  
Early Phases

Skeletal muscle regeneration is a complex process involving crosstalk between immune cells and myogenic precursor cells, i.e., satellite cells. In this scenario, macrophage recruitment in damaged muscles is a mandatory step for tissue repair since pro-inflammatory M1 macrophages promote the activation of satellite cells, stimulating their proliferation and then, after switching into anti-inflammatory M2 macrophages, they prompt satellite cells’ differentiation into myotubes and resolve inflammation. Here, we show that acid sphingomyelinase (ASMase), a key enzyme in sphingolipid metabolism, is activated after skeletal muscle injury induced in vivo by the injection of cardiotoxin. ASMase ablation shortens the early phases of skeletal muscle regeneration without affecting satellite cell behavior. Of interest, ASMase regulates the balance between M1 and M2 macrophages in the injured muscles so that the absence of the enzyme reduces inflammation. The analysis of macrophage populations indicates that these events depend on the altered polarization of M1 macrophages towards an M2 phenotype. Our results unravel a novel role of ASMase in regulating immune response during muscle regeneration/repair and suggest ASMase as a supplemental therapeutic target in conditions of redundant inflammation that impairs muscle recovery.

In silico evaluation of NO donor heterocyclic vasodilators as SARS-CoV-2 Mpro protein inhibitor

2021 ◽  
pp. 1-18
Author(s):  
Abdullah G. Al-Sehemi ◽  
Rishikesh S. Parulekar ◽  
Mehboobali Pannipara ◽  
Manzur Ali P P ◽  
Pudukulathan K. Zubaidha ◽  
...  
Keyword(s):  
In Silico ◽  
Protein Inhibitor ◽  
No Donor

Functional characteristics of PMJ2-R macrophages

2020 ◽  
Vol 18 (4) ◽  
pp. 133-137
Author(s):  
P.M. Kozhin ◽  
◽  
A.L. Rusanov ◽  
O.O. Shoshina ◽  
N.G. Luzgina ◽  
...  
Keyword(s):  
Cell Biology ◽  
Alternative Pathway ◽  
Peritoneal Macrophages ◽  
Alternative Activation ◽  
M2 Macrophages ◽  
Phagocytic Cells ◽  
Phenotypic Properties ◽  
M1 Macrophages ◽  
Oxidized Dextran ◽  
Tnf Α

Objective. To evaluate the ability of PMJ2-R cells for classical and alternative activation and to assess the effect of oxidized dextran on the functional status of polarized cells of this line. OD is a promising lysosomotropic agent used for targeted drug delivery to phagocytic cells. Materials and methods. We analyzed ability of immortalized murine peritoneal macrophages PMJ2R (ATCC CRL2458) to classical and alternative polarization, including that upon exposure to OD. We used real-time polymerase chain reaction to assess gene expression of competing arginine pathways. The capacity of phagocytes to engulf zymosan granules was evaluated using fluorescence microscopy. Results. We observed metabolic changes in PMJ2-R cells following their classical and alternative activation; these changes were typical of M1 and M2 macrophages, respectively. M1 macrophages demonstrated most active phagocytosis, while the activity of phagocytosis in M2 macrophages increased dose-dependently upon AD exposure. OD upregulates production of proinflammatory cytokine TNF-α in intact PMJ2-R cells and M1 macrophages. Conclusion. PMJ2-R cells have the capacity to phagocytose particles, can be polarized via the classical and alternative pathway, can modulate their functional activity in response to OD (a macrophagotropic substance), and exhibit the main phenotypic properties typical of peritoneal macrophages from C57Bl/6J mice. Therefore, cells of this line can be used as model cells in the investigation of phagocytic cell biology and pathology. Key words: alternative activation, classical activation, oxidized dextran, peritoneal macrophages, phagocytosis, C57Bl/6J, PMJ2-R

Abstract 660: Macrophage Specific Deficiency of the Transient Receptor Potential Canonical 3 Channel Reduces Apoptosis and Necrosis in Advanced Atherosclerotic Plaques

2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Sumeet A Solanki ◽  
Guillermo Vazquez
Keyword(s):  
Bone Marrow ◽  
Transient Receptor Potential ◽  
Receptor Potential ◽  
Atherosclerotic Plaques ◽  
M2 Macrophage ◽  
M2 Macrophages ◽  
M1 Macrophages ◽  
Transient Receptor Potential Canonical ◽  
Transient Receptor ◽  
Apoptosis And Necrosis

Background: Macrophage apoptosis plays a critical role in progression of atherosclerosis. Previous studies suggest that M1 and M2 macrophage phenotypes dominate atherosclerosis. Recently, we showed that advanced lesions in the aortic root of Apoe -/- mice transplanted with bone marrow deficient in the calcium-permeable channel Transient Receptor Potential Canonical 3 (TRPC3) are characterized by reduced areas of necrosis and less apoptotic macrophages. However, the donor mice used in these studies had global deficiency of TRPC3, raising the question whether the observed phenotype was also contributed by TRPC3-deficient non-myeloid cells which could undermine the true impact of macrophage deletion of TRPC3. To address this important question, we generated mice with macrophage-specific loss of TRPC3 function (MacTrpc3 -/- ). Methods & results: 13 six week-old female Ldlr -/- mice were irradiated and transplanted with Ldlr -/- (control) or MacTrpc3 -/- Ldlr -/- (experimental) bone marrow and kept on high fat diet for 14 weeks. At the end of the diet period, aortic roots were sectioned and processed for atherosclerotic lesion analysis. Total lesion size (H&E), neutral lipid (Oil Red O) and macrophage content (CD68 staining) were not different between groups. However, we found a 1.7 fold decrease (P=0.01) in percent necrotic area in advanced lesions of MacTrpc3 -/- Ldlr -/- mice (23.12 ± 2.07%, n=10) compared to controls (39.63 ± 5.93%, n=10). Using in situ TUNEL we found that MacTrpc3 -/- Ldlr -/- lesions have less apoptotic cells compared to controls, and these overlapped with CD68 + areas. Using iNOS and mannose receptor as markers for M1 and M2 macrophages, respectively, we found that both subsets overlapped with CD68 + and TUNEL + positive areas, with no differences between groups (n=5). Previously, we showed that M1, but not M2 macrophages derived from MacTrpc3 -/- mice, had reduced apoptosis. This suggests that reduced plaque necrosis of MacTrpc3 -/- Ldlr -/- mice may be due to reduced apoptosis of M1 macrophages. In sum, these in vivo studies indicate that macrophage-specific deficiency of TRPC3 has a genuine beneficial effect on advanced atherosclerotic plaques, reducing apoptosis and necrosis, probably due to a selective effect of TRPC3 on M1 macrophages.

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