LPS‐induced Toll‐like receptor 4 signalling triggers cross‐talk of apoptosis signal‐regulating kinase 1 (ASK1) and HIF‐1α protein

Sumbayev, Vadim V.

doi:10.1016/j.febslet.2007.12.024

Cited by 62 publications

(121 citation statements)

References 28 publications

(43 reference statements)

Supporting

Mentioning

111

Contrasting

Order By: Relevance

“…Since TLR7/8 are associated with the MyD88 adaptor, which is known to promote generation of ROS and RNS [2,6,13], we hypothesised that redox-and RNS-dependent mechanisms may be employed in TLR7/8-induced accumulation of HIF-1a protein. Signaling pathways induced by some TLRs, including TLR7/8, lead to the activation of tyrosine kinases, such as Bruton's tyrosine kinase (Btk) [14], that interact with MyD88, which binds to the TLR TIR domain.…”

Section: Tlr7/8 Trigger Hif-1a Accumulation Via Redox-and Rns-dependementioning

confidence: 99%

“…These data suggest that TLR7/8-dependent accumulation of HIF-1a protein is achieved via redox-and RNS-dependent mechanisms. This indicates that membrane-associated TLR4 and endosomal TLR7/8 utilize different mechanisms for HIF1a accumulation, since the ASK1-p38 pathway does not play any role in R848-induced HIF-1a accumulation but is crucial in the case of TLR4 signaling [6]. In addition, we have shown that HIF-1a knockdown with siRNA in THP-1 myeloid macrophages leads to a depletion of ATP, a decrease in R848-induced production of interleukin-6 (IL-6) and tumour necrosis factor alpha (TNFa), and a significant increase in caspase-3 activity.…”

Section: Introductionmentioning

confidence: 99%

“…It has been recently shown that apoptosis signal regulating kinase 1 (ASK1)-activated p38 MAP kinase contributes to HIF-1a stabilisation during LPS-induced TLR4 signaling [6]. To investigate the role of this pathway in R848-induced TLR7/8-mediated HIF-1a accumulation, we either transfected the cells with 2.5 µg/ml dominant-negative form of ASK1 (ASKI-KM) or pretreated them for 1 h with 10 µM SB203580 (p38 inhibitor), followed by 4 h of stimulation with 0.1 µg/ml R848.…”

Section: Tlr7/8 Trigger Hif-1a Accumulation Via Redox-and Rns-dependementioning

confidence: 99%

“…However, the molecular mechanisms of cell survival and adaptation to TLR7/8-induced stress, which give the cells an opportunity to initiate proper inflammatory reactions, are not clear at all. Recently it has been found that signaling by membrane-associated TLR4, which specifically recognises lipopolysaccharide (LPS) shared by Gram-negative bacteria, induces the accumulation of hypoxia-inducible factor 1 alpha (HIF-1a) [6]. HIF-1a is the inducible subunit of the heterodimeric HIF-1 transcription complex, which consists of two subunits, HIF1a and HIF-1b [7].…”

Section: Introductionmentioning

confidence: 99%

“…Otherwise HIF-1a protein undergoes rapid ubiquitination followed by proteasomal degradation [9]. LPS induces accumulation of HIF-1a protein via NADPH oxidase (Nox)-associated cross-talk with the mitogen-activated protein (MAP) kinase cascade [6]. In general, HIF-1a as a transcription factor, plays a pivotal role in mediating angiogenesis, glycolysis and cell adhesion [10], which are critical for inflammation.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

The involvement of hypoxia-inducible factor 1 alpha in Toll-like receptor 7/8-mediated inflammatory response

2009

View full text Add to dashboard Cite

Section: Tlr7/8 Trigger Hif-1a Accumulation Via Redox-and Rns-dependementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Tlr7/8 Trigger Hif-1a Accumulation Via Redox-and Rns-dependementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

The involvement of hypoxia-inducible factor 1 alpha in Toll-like receptor 7/8-mediated inflammatory response

2009

View full text Add to dashboard Cite

Improving the Time Resolution for Remote Control of Enzyme Activity by a Nanosecond Laser‐Induced pH Jump

Kohse¹,

Neubauer²,

Lochbrunner³

et al. 2014

ChemCatChem

View full text Add to dashboard Cite

Application of light as a trigger for remote control of enzyme activation offers high temporal and spatial resolution. A known enzymatic system based on an acid phosphatase and 6‐chloro‐8‐fluoro‐4‐methylumbelliferone phosphate as substrate is employed to study different strategies for improving the time resolution of enzyme activation by a light‐induced pH jump. Hence, a single laser pulse excitation with a pulse duration of 6 ns resulted in a 4‐fold enzyme activation by instantaneous proton release through the rearrangement of 2‐nitrobenzaldehyde. The time resolution of the activation experiment is now limited only by the detection system, no longer by the excitation step. In addition, halogenated 2‐nitrobenzaldehydes are tested for their suitability as phototriggers and a detailed study of the pH‐dependent kinetics of the enzymatic reaction is performed, which reveals that the substrate can probably only bind to the enzyme in its monoanionic form.

show abstract

Involvement of hypoxia‐inducible factor‐1 HiF(1α) in IgE‐mediated primary human basophil responses

et al. 2009

Self Cite

View full text Add to dashboard Cite

Basophils play a pivotal role in regulating chronic allergic inflammation as well as angiogenesis. Here, we show for the first time that IgE-mediated activation of primary human basophils results in protein accumulation of the a-subunit of hypoxia-inducible factor 1a (HIF-1a), which is differentially regulated compared with signals controlling histamine release. HIF-1 facilitates cellular adaptation to hypoxic conditions such as inflammation and tumour growth by controlling glycolysis, angiogenesis and cell adhesion. ERK and p38 MAPK, but not reactive oxygen species (ROS), ASK1 or PI 3-kinase, were critical for IgEmediated accumulation of HIF-1a, although the latter crucially affected degranulation. Abrogating HIF-1a expression in basophils using siRNA demonstrated that this protein is essential for vascular endothelial growth factor (VEGF) mRNA expression and, consequently, release of VEGF protein. In addition, HIF-1a protein alters IgE-induced ATP depletion in basophils, thus also supporting the production of the pro-allergic cytokine IL-4.Key words: Allergology . Molecular immunology . Signal transduction Introduction Basophils are comparatively rare granulocytes in the blood, which have multiple functions and migrate into organs affected by allergic inflammation and certain parasitic as well as autoimmune diseases [1]. In recent years there is increasing evidence suggesting that basophils are essential in orchestrating chronic allergic inflammation (reviewed in [2]). Although basophil numbers are low compared with mast cells, they are several orders of magnitude more sensitive to IgE-mediated activation than mast cells and are the main allergic effector cells capable of rapidly generating Th2-type cytokines in humans [3][4][5]. Furthermore, numerous studies have demonstrated that basophils migrate from the blood into various tissues affected by allergic inflammation (reviewed in [1] and [2]) where they are the principle IL-4-generating cells in developing late-phase responses [6]. By virtue of their ability to release histamine, leukotriene C 4 and Th2-type cytokines (e.g. IL-4) following allergen-mediated aggregation of high-affinity IgE receptors (FceRI), basophils potentially play an important pro-inflammatory and immunomodulatory role in allergy (reviewed in [2]). Furthermore, recent studies clearly implicate basophils in crucially regulating chronic allergic inflammation [7] and Th2-immunity [8]. Additionally, these cells were also found to play an important role in angiogenesis due to their ability to generate vascular endothelial growth factor (VEGF) [9].The activities of various intracellular signals involved in controlling both the synthesis and the secretion of these different mediator types from basophils lead to considerable demands in ATP generation (required in the phosphorylation of kinases). One possible mechanism that would explain the ability of basophils to contend with an increased demand in ATP, without undergoing cell death, as well as being able to produce VEGF, is due to the actions o...

show abstract

LPS‐induced Toll‐like receptor 4 signalling triggers cross‐talk of apoptosis signal‐regulating kinase 1 (ASK1) and HIF‐1α protein

Cited by 62 publications

References 28 publications

The involvement of hypoxia-inducible factor 1 alpha in Toll-like receptor 7/8-mediated inflammatory response

The involvement of hypoxia-inducible factor 1 alpha in Toll-like receptor 7/8-mediated inflammatory response

Improving the Time Resolution for Remote Control of Enzyme Activity by a Nanosecond Laser‐Induced pH Jump

Involvement of hypoxia‐inducible factor‐1 HiF(1α) in IgE‐mediated primary human basophil responses

Contact Info

Product

Resources

About