scholarly journals Achyranthes bidentata Polysaccharide Activates Nuclear Factor-Kappa B and Promotes Cytokine Production in J774A.1 Cells Through TLR4/MyD88 Signaling Pathway

2021 ◽  
Vol 12 ◽  
Author(s):  
Sairong Fan ◽  
Yanxing Wang ◽  
Yue Zhang ◽  
Yamin Wu ◽  
Xiaoming Chen

Achyranthes bidentata Blume, a traditional Chinese medicine, is widely acknowledged for its function of invigorating the liver and kidneys and as a stranguria-relieving diuretic and used in the treatment of edema, gonorrhea, and other diseases. Polysaccharide (ABPS), isolated from Achyranthes bidentata Blume, has been demonstrated to have multiple biological activities including immunomodulatory effects. However, the mechanisms underlying the effects of ABPS have not been fully investigated. The present study is conducted to explore the underlying mechanism of immunomodulatory activities of ABPS. Results showed that ABPS significantly increased the secretion of IL-1β and TNF-α in J744 A.1 cells. Nitric oxide (NO) also significantly increased after ABPS treatment. The special antibodies (Toll-like receptor 4 (TLR4) antibody and CD14/TLR4 antibody) significantly decreased the activation, while the Toll-like receptor 2 (TLR2) antibody could not abolish this activation. Meanwhile, pyrrolidine dithiocarbamate (PDTC), a specific inhibitor of NF-κB, remarkably inhibited the secretion of IL-1β and TNF-α induced by ABPS in J744 A.1 cells. Western blotting (WB) and confocal laser scanning microscopy (CLSM) showed that ABPS promoted NF-κB translocation into the nucleus. Furthermore, the mRNA and protein expression of TLR4 and MyD88 were significantly increased after ABPS treatment. Taken together, these findings suggested that the immunomodulatory mechanism of ABPS was associated with the secretion of cytokines by stimulating the NF-κB pathway through TLR4/MyD88 signaling.

2006 ◽  
Vol 290 (6) ◽  
pp. R1496-R1507 ◽  
Author(s):  
D. Günzel ◽  
P. Florian ◽  
J. F. Richter ◽  
H. Troeger ◽  
J. D. Schulzke ◽  
...  

Integrity of colon epithelium is of crucial importance and, as small defects occur constantly, rapid repair (restitution) is essential. To investigate the mechanism of restitution, single-cell lesions were induced in mouse colonic surface epithelia by iontophoretic injection of Ca2+. Closure of the resulting defects was monitored using confocal laser scanning microscopy (CLSM), and functional sealing by electrophysiological techniques. Restitution was evaluated as the time constant τ of the exponential decrease in conductance of an induced leak and amounted to 0.28 min under control conditions. After 4 min, the leak was completely sealed. Repair was thus considerably faster than in previously investigated HT-29/B6 cells (τ = 5.73 min). As in cultured cells, cytochalasin D delayed restitution in native colon epithelia (τ = 0.69 min), indicating the involvement of actin in the healing process; however, no accumulation of actin surrounding the lesion was detected. Long-term incubation of epithelia with IFN-γ alone or in combination with TNF-α increased τ to 0.49 and 0.59 min, respectively. In contrast to cultured cells, TNF-α alone did not affect restitution. A brief (<10 min) exposure to the sterile filtered supernatant of hemolytic E. coli O4 cultures did not affect the morphology of the epithelium, but delayed restitution. In CLSM studies, defects were still clearly visible 4 min after the onset of lesion induction. The supernatant of a nonhemolytic E. coli O4 mutant did not exhibit this effect. In conclusion, single-cell defects in native colon cause functional leaks that seal faster than in cell cultures. Proinflammatory cytokines and pathogenic bacteria delay restitution. This suggests a key role of very small lesions at the onset of pathogenic processes in the intestine.


1997 ◽  
Vol 110 (17) ◽  
pp. 2089-2097 ◽  
Author(s):  
A.M. Benoliel ◽  
B. Kahn-Peries ◽  
J. Imbert ◽  
P. Verrando

Insulin-mediated cell motility as well as the role of transcription factors in insulin-activated intracellular signal events have not been extensively studied. In this report we have examined whether insulin could mediate haptotactic migration of cultured human epidermal keratinocytes through activation of transcription factor NF-kappa B. Insulin caused a dose-dependent stimulation of keratinocyte migration that maximally reached 2-fold at 2 × 10(−7) M hormone. This phenomenon was independent of the nature of the extracellular matrix component (collagen I or laminin5/nicein) on which the cells migrated, indicating that a specific integrin-ligand complex is not required. A 10(−7) M insulin treatment of keratinocytes resulted in activation of a major kappa B DNA binding complex within 15 to 30 minutes, which was identified as the p65/p50 NF-kappa B heterodimer by electrophoretic mobility shift assays. The activation induced nuclear translocation of cytosolic pools of NF-kappa B factor. Pyrrolidine dithiocarbamate and N-acetyl-leucinyl-leucinyl-norleucinal H (two compounds that differentially inhibit I kappa B alpha degradation and, thus, NF-kappa B activation) reversed the insulin-stimulated keratinocyte haptotactic migration without affecting insulin receptor activation. These compounds inhibited the insulin-induced nuclear translocation of NF-kappa B as detected by confocal laser scanning microscopy. Taken together our experiments demonstrate that insulin stimulates haptotactic migration of human epidermal keratinocytes through activation of NF-kappa B transcription factor. They emphasize the ability of insulin to stimulate keratinocyte movement and provide a first clue to the mechanism of insulin-induced haptotactic signaling.


2011 ◽  
Vol 18 (9) ◽  
pp. 1416-1419 ◽  
Author(s):  
Saleh A. Naser ◽  
Claudia Romero ◽  
Princess Urbina ◽  
Najih Naser ◽  
John Valentine

ABSTRACTThe purpose of this study was to determine the degree of infiltration of different cell subpopulations (tissue dendritic macrophages, T-helper cells, cytotoxic T lymphocytes, monocytes, neutrophils, and B cells) and the expression of the cytokines interleukin-12 (IL-12) and tumor necrosis factor alpha (TNF-α) in inflamed and noninflamed resected tissues from Crohn's disease (CD) and non-CD patients. Twenty-one resected full-thickness intestinal tissue specimens representing 13 subjects (8 CD and 5 non-CD patients) were included in this study. Sections of 20 μm in thickness were cut and then stained using immunohistochemistry. The sections were analyzed using confocal laser scanning microscopy (CLSM). Patterns of staining for inflamed CD and noninflamed CD tissues versus non-CD tissues demonstrated significant differences in the macrophage and T-helper subpopulations. Surprisingly, the T-helper subset was decreased significantly in the inflamed CD sections compared to the noninflamed CD and non-CD sections. The staining patterns also suggested differences in the expression of both IL-12 and TNF-α between the groups, with cytokine overexpression directly relating to the fistulizing state in CD patients. Cytokine expression is upregulated in chronic CD patients; therefore, the degree of inflammation and tissue damage in CD is dependent on the expression of specific cytokines within the tissue. Differentiation of cell subpopulations may be important for establishing a direct relationship with each state of CD (inflammatory, stricturing, and fistulizing states).


Author(s):  
Thomas M. Jovin ◽  
Michel Robert-Nicoud ◽  
Donna J. Arndt-Jovin ◽  
Thorsten Schormann

Light microscopic techniques for visualizing biomolecules and biochemical processes in situ have become indispensable in studies concerning the structural organization of supramolecular assemblies in cells and of processes during the cell cycle, transformation, differentiation, and development. Confocal laser scanning microscopy offers a number of advantages for the in situ localization and quantitation of fluorescence labeled targets and probes: (i) rejection of interfering signals emanating from out-of-focus and adjacent structures, allowing the “optical sectioning” of the specimen and 3-D reconstruction without time consuming deconvolution; (ii) increased spatial resolution; (iii) electronic control of contrast and magnification; (iv) simultanous imaging of the specimen by optical phenomena based on incident, scattered, emitted, and transmitted light; and (v) simultanous use of different fluorescent probes and types of detectors.We currently use a confocal laser scanning microscope CLSM (Zeiss, Oberkochen) equipped with 3-laser excitation (u.v - visible) and confocal optics in the fluorescence mode, as well as a computer-controlled X-Y-Z scanning stage with 0.1 μ resolution.


Author(s):  
M. H. Chestnut ◽  
C. E. Catrenich

Helicobacter pylori is a non-invasive, Gram-negative spiral bacterium first identified in 1983, and subsequently implicated in the pathogenesis of gastroduodenal disease including gastritis and peptic ulcer disease. Cytotoxic activity, manifested by intracytoplasmic vacuolation of mammalian cells in vitro, was identified in 55% of H. pylori strains examined. The vacuoles increase in number and size during extended incubation, resulting in vacuolar and cellular degeneration after 24 h to 48 h. Vacuolation of gastric epithelial cells is also observed in vivo during infection by H. pylori. A high molecular weight, heat labile protein is believed to be responsible for vacuolation and to significantly contribute to the development of gastroduodenal disease in humans. The mechanism by which the cytotoxin exerts its effect is unknown, as is the intracellular origin of the vacuolar membrane and contents. Acridine orange is a membrane-permeant weak base that initially accumulates in low-pH compartments. We have used acridine orange accumulation in conjunction with confocal laser scanning microscopy of toxin-treated cells to begin probing the nature and origin of these vacuoles.


TAPPI Journal ◽  
2010 ◽  
Vol 9 (10) ◽  
pp. 7-15
Author(s):  
HANNA KOIVULA ◽  
DOUGLAS BOUSFIELD ◽  
MARTTI TOIVAKKA

In the offset printing process, ink film splitting has an important impact on formation of ink filaments. The filament size and its distribution influence the leveling of ink and hence affect ink setting and the print quality. However, ink filaments are difficult to image due to their short lifetime and fine length scale. Due to this difficulty, limited work has been reported on the parameters that influence filament size and methods to characterize it. We imaged ink filament remains and quantified some of their characteristics by changing printing speed, ink amount, and fountain solution type. Printed samples were prepared using a laboratory printability tester with varying ink levels and operating settings. Rhodamine B dye was incorporated into fountain solutions to aid in the detection of the filaments. The prints were then imaged with a confocal laser scanning microscope (CLSM) and images were further analyzed for their surface topography. Modeling of the pressure pulses in the printing nip was included to better understand the mechanism of filament formation and the origin of filament length scale. Printing speed and ink amount changed the size distribution of the observed filament remains. There was no significant difference between fountain solutions with or without isopropyl alcohol on the observed patterns of the filament remains.


2012 ◽  
Vol 11 (3) ◽  
pp. 669-674 ◽  
Author(s):  
Szabolcs Szilveszter ◽  
Botond Raduly ◽  
Szilard Bucs ◽  
Beata Abraham ◽  
Szabolcs Lanyi ◽  
...  

2009 ◽  
Vol 18 (1) ◽  
pp. 11-16
Author(s):  
E.V. Soldatenko ◽  
A.A. Petrov

The morphology of the copulatory apparatus and associated cuticular structures in Planorbis planorbis was studied by light microscopy, SEM, TEM and confocal laser scanning microscopy. The significance of these cuticular structures for the taxonomic status of the species and for the systematics of the family Planorbidae in general is discussed.


Sign in / Sign up

Export Citation Format

Share Document