Signal transduction by the high-affinity IgE receptor (FcεRI) depends on membrane lipid and protein compartmentalization. Recently published data show that cells treated with 1-heptanol, a cell membrane fluidizer, exhibit changes in membrane properties. However, the functional consequences of 1-heptanol-induced changes on mast cell signaling are unknown. This study shows that short-term exposure to 1-heptanol reduces membrane thermal stability and dysregulates mast cell signaling at multiple levels. Cells treated with 1-heptanol exhibited increased lateral mobility and decreased internalization of the FcεRI. However, this did not affect the initial phosphorylation of the FcεRI-β chain and components of the SYK/LAT1/PLCγ1 signaling pathway after antigen activation. In contrast, 1-heptanol inhibited SAPK/JNK phosphorylation and effector functions such as calcium response, degranulation, and cytokine production. Membrane hyperfluidization induced a heat shock-like response via increased expression of the heat shock protein 70, increased lateral diffusion of ORAI1-mCherry, and unsatisfactory performance of STIM1-ORAI1 coupling, as determined by flow-FRET. Furthermore, 1-heptanol inhibited the antigen-induced production of reactive oxygen species and potentiated stress-induced plasma membrane permeability by interfering with heat shock protein 70 activity. The combined data suggest that 1-heptanol-mediated membrane fluidization does not interfere with the earliest biochemical steps of FcεRI signaling, such as phosphorylation of the FcεRI-β chain and components of the SYK/LAT/PLCγ1 signaling pathway, instead inhibiting the FcεRI internalization and mast cell effector functions, including degranulation and cytokine production.
- Klíčová slova
- FRAP, FcεRI signaling, STIM1-ORAI1 coupling, alkanol, flow-FRET, heat shock response, membrane fluidizer, store-operated calcium entry,
- MeSH
- cholesterol MeSH
- cytokiny MeSH
- heptanol MeSH
- mastocyty * MeSH
- signální transdukce * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- cholesterol MeSH
- cytokiny MeSH
- heptanol MeSH
Electromembrane extraction (EME) and CE with capacitively coupled contactless conductivity detection (CE-C(4) D) was applied to rapid and sensitive determination of perchlorate in drinking water and environmental samples. Porous polypropylene hollow fiber impregnated with 1-heptanol acted as a supported liquid membrane (SLM) and perchlorate was transported and preconcentrated in the fiber lumen on application of electric field. High selectivity of perchlorate determination and its baseline separation from major inorganic anions was achieved in CE-C(4) D using background electrolyte solution consisting of 7.5 mM L-histidine and 40 mM acetic acid at pH 4.1. The analytical method showed excellent parameters in terms of reproducibility; RSD values for migration times and peak areas at a spiked concentration of 15 μg/L of perchlorate (US EPA recommended limit for drinking water) were below 0.2 and 8.7%, respectively, in all examined water samples. Linear calibration curves were obtained for perchlorate in the concentration range 1-100 μg/L (r(2) ≥0.999) with limits of detection at 1 μg/L for tap water and at 0.25-0.35 μg/L for environmental and bottled potable water samples. Recoveries at 15 μg/L of perchlorate were between 95.9 and 106.7% with minimum and maximum recovery values for snow and bottled potable water samples, respectively.
- MeSH
- chemická frakcionace přístrojové vybavení metody MeSH
- déšť chemie MeSH
- elektrická vodivost MeSH
- elektroforéza kapilární metody MeSH
- elektrolyty chemie MeSH
- heptanol chemie MeSH
- histidin chemie MeSH
- koncentrace vodíkových iontů MeSH
- kyselina octová chemie MeSH
- membrány umělé * MeSH
- perchloráty analýza izolace a purifikace MeSH
- reprodukovatelnost výsledků MeSH
- senzitivita a specificita MeSH
- voda chemie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- elektrolyty MeSH
- heptanol MeSH
- histidin MeSH
- kyselina octová MeSH
- membrány umělé * MeSH
- perchlorate MeSH Prohlížeč
- perchloráty MeSH
- voda MeSH
