scholarly journals Responsiveness of human neutrophils to interleukin-4: induction of cytoskeletal rearrangements, de novo protein synthesis and delay of apoptosis

1997 ◽  
Vol 325 (1) ◽  
pp. 147-153 ◽  
Author(s):  
Denis GIRARD ◽  
Robert PAQUIN ◽  
André D. BEAULIEUL
Keyword(s):  
Protein Synthesis ◽  
De Novo ◽  
Biological Activities ◽  
Interleukin 4 ◽  
Human Neutrophils ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Cytoskeletal Rearrangements ◽  
First Time ◽  
De Novo Protein Synthesis

Interleukin-4 (IL-4) and IL-13 are cytokines that share many biological activities. We have previously demonstrated that IL-13 affects a number of neutrophil responses, and here we extend our observations to IL-4. We present, for the first time, direct evidence for the presence of functional IL-4 receptors on human neutrophils. We report that IL-4 induces RNA synthesis in a concentration-dependent manner and, based on observations of the induction of morphological cell shape changes and spreading onto glass, we demonstrate that IL-4 activates neutrophil cytoskeletal rearrangements. We further show that IL-4 is a potent activator of de novo protein synthesis in neutrophils, and we identify by microsequencing one of these proteins as the cytoskeletal protein actin. We were also able to demonstrate for the first time that actin is cleaved into at least two fragments of ∼ 30 kDa (pI 5.4) and ∼ 25 kDa (pI 5.0) in neutrophils. Finally, we report that IL-4 delays neutrophil apoptosis, as assessed by morphological observations from cytocentrifuge preparations, as well as by measurement of differences in staining by flow cytometry with both propidium iodide and Hoechst reagent. Taken together, we conclude that IL-4 is a more potent neutrophil agonist than previously believed. We discuss the possibility that the induction of the de novo synthesis of actin by IL-4 is related to the mechanism by which this cytokine delays apoptosis; in addition, the cleavage of this protein is likely to contribute to the apoptotic process.

Influence of ammonia concentration on [15N]ammonia uptake andde novosynthesis of different amino acids by mixed rumen microorganisms from the sheep rumenin vitro

1999 ◽  
Vol 1999 ◽  
pp. 212-212 ◽  
Author(s):  
C. Atasoglu ◽  
C.J. Newbold ◽  
R.J. Wallace
Keyword(s):  
Amino Acids ◽  
Protein Synthesis ◽  
De Novo ◽  
Ammonia Concentration ◽  
Dependent Manner ◽  
Microbial Protein ◽  
Concentration Dependent Manner ◽  
Rumen Microorganisms ◽  
Ammonia Uptake

Ammonia is thought to be the main source of nitrogen for protein synthesis by the rumen microorganisms, but peptides and amino acids derived from protein degradation are also incorporated into microbial protein. Recent experiments carried out by Atasogluet al.(1998) demonstrated that preformed amino acids decrease the uptake of ammonia into microbial protein and microbial amino acids in a concentration-dependent manner. However, little is known about how rumen ammonia concentrations affect ammonia uptake into microbial protein. The present study was undertaken to determine the influence of rumen ammonia concentrations on ammonia incorporation andde novosynthesis of individual amino acids by the mixed rumen microorganismsin vitro.

scholarly journals Modulatory Effect of Chelidonium majus Extract and Its Alkaloids on LPS-Stimulated Cytokine Secretion in Human Neutrophils

Molecules ◽  
2020 ◽  
Vol 25 (4) ◽  
pp. 842 ◽  
Author(s):  
Sylwia Zielińska ◽  
Monika Ewa Czerwińska ◽  
Magdalena Dziągwa-Becker ◽  
Andrzej Dryś ◽  
Mariusz Kucharski ◽  
...  
Keyword(s):  
Biological Activities ◽  
Cytokine Secretion ◽  
Human Neutrophils ◽  
Root Extract ◽  
Dependent Manner ◽  
Chelidonium Majus ◽  
Concentration Dependent Manner ◽  
Cytotoxic Effects ◽  
Tnf Α ◽  
High Cytotoxicity

Due to certain differences in terms of molecular structure, isoquinoline alkaloids from Chelidonium majus engage in various biological activities. Apart from their well-documented antimicrobial potential, some phenanthridine and protoberberine derivatives as well as C. majus extract present with anti-inflammatory and cytotoxic effects. In this study, the LC–MS/MS method was used to determine alkaloids, phenolic acids, carboxylic acids, and hydroxybenzoic acids. We investigated five individually tested alkaloids (coptisine, berberine, chelidonine, chelerythrine, and sanguinarine) as well as C. majus root extract for their effect on the secretion of IL-1β, IL-8, and TNF-α in human polymorphonuclear leukocytes (neutrophils). Berberine, chelidonine, and chelerythrine significantly decreased the secretion of TNF-α in a concentration-dependent manner. Sanguinarine was found to be the most potent inhibitor of IL-1β secretion. However, the overproduction of IL-8 and TNF-α and a high cytotoxicity for these compounds were observed. Coptisine was highly cytotoxic and slightly decreased the secretion of the studied cytokines. The extract (1.25–12.5 μg/mL) increased cytokine secretion in a concentration-dependent manner, but an increase in cytotoxicity was also noted. The alkaloids were active at very low concentrations (0.625–2.5 μM), but their potential cytotoxic effects, except for chelidonine and chelerythrine, should not be ignored.

scholarly journals Signal transduction for chemotaxis and haptotaxis by matrix molecules in tumor cells.

1990 ◽  
Vol 110 (4) ◽  
pp. 1427-1438 ◽  
Author(s):  
S Aznavoorian ◽  
M L Stracke ◽  
H Krutzsch ◽  
E Schiffmann ◽  
L A Liotta
Keyword(s):  
Protein Synthesis ◽  
Matrix Protein ◽  
Type Iv Collagen ◽  
De Novo ◽  
Protein Synthesis Inhibitor ◽  
Dependent Manner ◽  
Recognition Sequence ◽  
Synthesis Inhibitor ◽  
Concentration Dependent Manner ◽  
Type Iv

Transduction of signals initiating motility by extracellular matrix (ECM) molecules differed depending on the type of matrix molecule and whether the ligand was in solution or bound to a substratum. Laminin, fibronectin, and type IV collagen stimulated both chemotaxis and haptotaxis of the A2058 human melanoma cell line. Peak chemotactic responses were reached at 50-200 nM for laminin, 50-100 nM for fibronectin, and 200-370 nM for type IV collagen. Checkerboard analysis of each attractant in solution demonstrated a predominantly directional (chemotactic) response, with a minor chemokinetic component. The cells also migrated in a concentration-dependent manner to insoluble step gradients of substratum-bound attractant (haptotaxis). The haptotactic responses reached maximal levels at coating concentrations of 20 nM for laminin and type IV collagen, and from 30 to 45 nM for fibronectin. Pretreatment of cells with the protein synthesis inhibitor, cycloheximide (5 micrograms/ml), resulted in a 5-30% inhibition of both chemotactic and haptotactic responses to each matrix protein, indicating that de novo protein synthesis was not required for a significant motility response. Pretreatment of cells with 50-500 micrograms/ml of synthetic peptides containing the fibronectin cell-recognition sequence GRGDS resulted in a concentration-dependent inhibition of fibronectin-mediated chemotaxis and haptotaxis (70-80% inhibition compared to control motility); negative control peptide GRGES had only a minimal effect. Neither GRGDS nor GRGES significantly inhibited motility to laminin or type IV collagen. Therefore, these results support a role for the RGD-directed integrin receptor in both types of motility response to fibronectin. After pretreatment with pertussis toxin (PT), chemotactic responses to laminin, fibronectin, and type IV collagen were distinctly different. Chemotaxis to laminin was intermediate in sensitivity; chemotaxis to fibronectin was completely insensitive; and chemotaxis to type IV collagen was profoundly inhibited by PT. In marked contrast to the inhibition of chemotaxis, the hepatotactic responses to all three ligands were unaffected by any of the tested concentrations of PT. High concentrations of cholera toxin (CT; 10 micrograms/ml) or the cAMP analogue, 8-Br-cAMP (0.5 mM), did not significantly affect chemotactic or haptotactic motility to any of the attractant proteins, ruling out the involvement of cAMP in the biochemical pathway initiating motility in these cells. The sensitivity of chemotaxis induced by laminin and type IV collagen, but not fibronectin, to PT indicates the involvement of a PT-sensitive G protein in transduction of the signals initiating motility to soluble laminin and type IV collagen.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals Production of Soluble Triggering Receptor Expressed on Myeloid Cells by Lipopolysaccharide-Stimulated Human Neutrophils Involves De Novo Protein Synthesis

2006 ◽  
Vol 13 (4) ◽  
pp. 492-495 ◽  
Author(s):  
Amr M. Mahdy ◽  
Damon A. Lowes ◽  
Helen F. Galley ◽  
Jane E. Bruce ◽  
Nigel R. Webster
Keyword(s):  
Protein Synthesis ◽  
De Novo ◽  
Myeloid Cells ◽  
Surface Expression ◽  
Soluble Form ◽  
Human Neutrophils ◽  
Lps Challenge ◽  
Alternatively Spliced ◽  
Culture Supernatants ◽  
De Novo Protein Synthesis

ABSTRACT The triggering receptor expressed on myeloid cells (TREM-1) is a recently identified receptor expressed on neutrophils and monocytes. Activation of the receptor induces neutrophils to release the enzyme myeloperoxidase and inflammatory cytokines such as interleukin-8. TREM-1 has an alternatively spliced variant that lacks the transmembrane region, resulting in the receptor being secreted in a soluble form (sTREM-1). Soluble TREM-1 has been detected in plasma during experimental and clinical sepsis and has been advocated as a diagnostic marker of infection for pneumonia and as a prognostic marker for patients with septic shock. We studied TREM-1 surface expression, using flow cytometry, and simultaneously measured sTREM-1 concentrations in culture supernatants of lipopolysaccharide (LPS)-stimulated neutrophils. TREM-1 surface expression was constitutive and was not upregulated upon LPS stimulation. However, sTREM-1 release from neutrophils was significantly upregulated by LPS stimulation (P < 0.0001), an effect that was abrogated by cycloheximide. Soluble TREM-1 is therefore secreted by human neutrophils in response to LPS challenge in a process involving de novo protein synthesis that is not accompanied by an upregulation of the TREM-1 receptor on the surfaces of the cells.

scholarly journals 1,25(OH)2D3 stimulates Mg2+uptake into MDCT cells: modulation by extracellular Ca2+and Mg2+

2001 ◽  
Vol 280 (5) ◽  
pp. F868-F878 ◽  
Author(s):  
Gordon Ritchie ◽  
Dirk Kerstan ◽  
Long-Jun Dai ◽  
Hyung Sub Kang ◽  
Lucie Canaff ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
De Novo ◽  
Divalent Cations ◽  
Gene Activation ◽  
Peptide Hormone ◽  
Distal Convoluted Tubule ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Dihydroxyvitamin D ◽  
Magnesium Uptake

The distal convoluted tubule plays a significant role in renal magnesium conservation. Although the cells of the distal convoluted tubule possess the vitamin D receptor, little is known about the effects of 1α,25-dihydroxyvitamin D [1,25(OH)2D3] on magnesium transport. In this study, we examined the effect of 1,25(OH)2D3 on distal cellular magnesium uptake and the modulation of this response by extracellular Ca2+and Mg2+ in an immortalized mouse distal convoluted tubule (MDCT) cell line. MDCT cells possess the divalent cation-sensing receptor (CaSR) that responds to elevation of extracellular Ca2+ and Mg2+ concentrations to diminish peptide hormone-stimulated Mg2+ uptake. Mg2+uptake rates were determined by microfluorescence in Mg2+-depleted MDCT cells. Treatment of MDCT cells with 1,25(OH)2D3 for 16–24 h stimulated basal Mg2+ uptake in a concentration-dependent manner from basal levels of 164 ± 5 to 210 ± 11 nM/s, representing a 28 ± 3% change. Pretreatment with actinomycin D or cycloheximide abolished 1,25(OH)2D3-stimulated.Mg2+uptake (154 ± 18 nM/s), suggesting that 1,25(OH)2D3 stimulates Mg2+ uptake through gene activation and protein synthesis. Elevation of extracellular Ca2+ inhibited 1,25(OH)2D3-stimulated Mg2+ uptake (143 ± 5 nM/s). Preincubation of the cells with an antibody to the CaSR prevented the inhibition by elevated extracellular Ca2+ of 1,25(OH)2D3-stimulated Mg2+ uptake (202 ± 8 nM/s). Treatment with an antisense CaSR mRNA oligodeoxynucleotide also abolished the effects of extracellular Ca2+ on 1,25(OH)2D3-responsive Mg2+ entry. This showed that elevated extracellular calcium modulates 1,25(OH)2D-mediated responses through the CaSR. In summary, 1,25(OH)2D3 stimulated Mg2+ uptake in MDCT cells, and this is dependent on de novo protein synthesis. Elevation of extracellular Ca2+, acting via the CaSR, inhibited 1,25(OH)2D3-stimulated Mg2+ entry. These data indicate that 1,25(OH)2D3 has important effects on the control of magnesium entry in MDCT cells and these responses can be modulated by extracellular divalent cations.

Platelet-activating factor and the kidney

1986 ◽  
Vol 251 (1) ◽  
pp. F1-F11 ◽  
Author(s):  
D. Schlondorff ◽  
R. Neuwirth
Keyword(s):  
De Novo ◽  
Mesangial Cells ◽  
Biological Activities ◽  
Platelet Activating Factor ◽  
Calcium Ionophore ◽  
Initial Step ◽  
Renal Physiology ◽  
Dependent Manner ◽  
Glomerular Mesangial Cells ◽  
Isolated Kidney

Platelet-activating factor (PAF) represents a group of phospholipids with the basic structure of 1-alkyl-2-acetyl-sn-glycero-3-phosphocholine. A number of different cells are capable of producing PAF in response to various stimuli. The initial step of PAF formation is activation of phospholipase A2 in a calcium-dependent manner, yielding lyso-PAF. During this step arachidonic acid is also released and can be converted to its respective cyclooxygenase and lipoxygenase products. The lyso-PAF generated is then acetylated in position 2 of the glycerol backbone by a coenzyme A (CoA)-dependent acetyltransferase. An additional pathway may exist whereby PAF is generated de novo from 1-alkyl-2-acetyl-sn-glycerol by phosphocholine transferase. PAF inactivation in cells and blood is by specific acetylhydrolases. PAF exhibits a variety of biological activities including platelet and leukocyte aggregation and activation, increased vascular permeability, respiratory distress, decreased cardiac output, and hypotension. In the kidney PAF can produce decreases in blood flow, glomerular filtration, and fluid and electrolyte excretion. Intrarenal artery injection of PAF may also result in glomerular accumulation of platelets and leukocytes and mild proteinuria. PAF increases prostaglandin formation in the isolated kidney and in cultured glomerular mesangial cells. PAF also causes contraction of mesangial cells. Upon stimulation with calcium ionophore the isolated kidney, isolated glomeruli and medullary cells, and cultured mesangial cells are capable of producing PAF. The potential role for PAF in renal physiology and pathophysiology requires further investigation that may be complicated by 1) the multiple interactions of PAF, prostaglandins, and leukotrienes and 2) the autocoid nature of PAF, which may restrict its action to its site of generation.

scholarly journals Bioactivity-Guided Extract Optimization of Osmanthus fragrans var. aurantiacus Leaves and Anti-Inflammatory Activities of Phillyrin

Plants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1545
Author(s):  
Hwa-Young Song ◽  
Da-Eun Jeong ◽  
Mina Lee
Keyword(s):  
Biological Activities ◽  
Radical Scavenging ◽  
No Production ◽  
Dependent Manner ◽  
Optimal Method ◽  
Concentration Dependent Manner ◽  
Osmanthus Fragrans ◽  
Tnf Α ◽  
Anti Inflammatory ◽  
Extracellular Regulated Kinase

The aim of this study was to identify the optimal extraction conditions for leaves of Osmanthus fragrans var. aurantiacus. Inhibitory effects of various extracts on NO production were compared. Antioxidant evaluations for total phenol and flavonoid contents were carried out using various extracts of O. fragrans var. aurantiacus leaves obtained under optimal extraction conditions that showed the greatest effect on NO production. The optimal method for extracting O. fragrans var. aurantiacus leaves resulted in an extract named OP OFLE. OP OFLE showed DPPH and ABTS radical scavenging activities in a concentration-dependent manner. Phillyrin (PH) was isolated as a major compound from OP OFLE by HPLC/DAD analysis. OP OFLE and PH reduced inducible nitric oxide (iNOS) and cyclooxygenase (COX)-2 protein expression and downregulated proinflammatory cytokines such as interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor (TNF)-α in LPS-stimulated RAW 264.7 and HT-29 cells. To determine the signal pathway involved in the inhibition of NO production, a Western blot analysis was performed. Results showed that OP OFLE decreased phosphorylation of extracellular regulated kinase (pERK) 1/2 and the expression of nuclear factor-kappa B (NF-κB). Our results suggest that extracts of O. fragrans var. aurantiacus leaves and its major components have biological activities such as antioxidative and anti-inflammatory properties.

scholarly journals Brassinolide Enhances the Level of Brassinosteroids, Protein, Pigments, and Monosaccharides in Wolffia arrhiza Treated with Brassinazole

Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1311
Author(s):  
Magdalena Chmur ◽  
Andrzej Bajguz
Keyword(s):  
Plant Growth ◽  
Growth And Development ◽  
Inhibitory Effect ◽  
Dependent Manner ◽  
Plant Growth And Development ◽  
Concentration Dependent Manner ◽  
Spectrophotometric Methods ◽  
Synthetic Inhibitor ◽  
Wolffia Arrhiza ◽  
First Time

Brassinolide (BL) represents brassinosteroids (BRs)—a group of phytohormones that are essential for plant growth and development. Brassinazole (Brz) is as a synthetic inhibitor of BRs’ biosynthesis. In the present study, the responses of Wolffia arrhiza to the treatment with BL, Brz, and the combination of BL with Brz were analyzed. The analysis of BRs and Brz was performed using LC-MS/MS. The photosynthetic pigments (chlorophylls, carotenes, and xanthophylls) levels were determined using HPLC, but protein and monosaccharides level using spectrophotometric methods. The obtained results indicated that BL and Brz influence W. arrhiza cultures in a concentration-dependent manner. The most stimulatory effects on the growth, level of BRs (BL, 24-epibrassinolide, 28-homobrassinolide, 28-norbrassinolide, catasterone, castasterone, 24-epicastasterone, typhasterol, and 6-deoxytyphasterol), and the content of pigments, protein, and monosaccharides, were observed in plants treated with 0.1 µM BL. Whereas the application of 1 µM and 10 µM Brz caused a significant decrease in duckweed weight and level of targeted compounds. Application of BL caused the mitigation of the Brz inhibitory effect and enhanced the BR level in duckweed treated with Brz. The level of BRs was reported for the first time in duckweed treated with BL and/or Brz.

Cytotoxic Effects of Ferula Latisecta on Human Glioma U87 Cells

Drug Research ◽  
2019 ◽  
Vol 69 (12) ◽  
pp. 665-670 ◽  
Author(s):  
Mohammad Jalili-Nik ◽  
Hamed Sabri ◽  
Ehsan Zamiri ◽  
Mohammad Soukhtanloo ◽  
Mostafa Karimi Roshan ◽  
...  
Keyword(s):  
Enzymatic Activity ◽  
Gelatin Zymography ◽  
Annexin V ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Ic50 Values ◽  
Induced Apoptosis ◽  
Natural Herb ◽  
First Time ◽  
U87 Cells

AbstractGlioblastoma multiforme (GBM) is the fatal type of astrocytic tumors with a survival rate of 12 months. The present study, for the first time, evaluated the cytotoxic impacts of Ferula latisecta (F. latisecta) hydroalcoholic extract on U87 GBM cell line. The MTT assay measured the cellular toxicity following 24- and 48 h treatment with various doses of F. latisecta (0–800 μg/mL). Apoptosis was evaluated by an Annexin V/propidium iodide (PI) staining 24 h after treatment by F. latisecta. Moreover, to determine the cellular metastasis of U87 cells, we used a gelatin zymography assay (matrix metalloproteinase [MMP]-2/-9 enzymatic activity). The outcomes showed that F. latisecta mitigated the viability of U87 cells in a concentration- and time-dependent manner with IC50 values of 145.3 and 192.3 μg/mL obtained for 24- and 48 h treatments, respectively. F. latisecta induced apoptosis in a concentration-dependent manner after 24 h. Also, MMP-9 activity was significantly decreased following 24 h after treatment concentration-dependently with no change in MMP-2 enzymatic activity. This study showed that F. latisecta induced cytotoxicity and apoptosis, and mitigated metastasis of U87 GBM cells. Hence, F. latisecta could be beneficial as a promising natural herb against GBM after further studies.

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