thapsigargin and caffeic-acid-phenethyl-ester

Interstitial cells of Cajal (ICCs) are pacemaker cells in the gastrointestinal (GI) tract and generate pacemaker potentials. In this study, we investigated the effects of caffeic acid phenethyl ester (CAPE) on the pacemaker potentials of ICCs from the mouse small or large intestine. Using the whole-cell patch-clamp configuration, we found that CAPE depolarized the pacemaker potentials of cultured ICCs from the murine small intestine in a dose-dependent manner. The estrogen receptor (ER) β antagonist PHTPP completely inhibited CAPE-induced depolarization, but the ERα antagonist BHPI did not. Intracellular GDP-β-S and pretreatment with Ca

Topics: Animals; Caffeic Acids; Calcium; Gastrointestinal Motility; Interstitial Cells of Cajal; Intestine, Small; Membrane Potentials; Mice; Mitogen-Activated Protein Kinases; Patch-Clamp Techniques; Phenylethyl Alcohol; Protein Kinase Inhibitors; Thapsigargin

Leukotrienes (LTs) are a class of lipid mediators implicated in numerous inflammatory disorders. Caffeic acid phenethyl ester (CAPE) possesses potent anti-LTs activity through the inhibition of 5-lipoxygenase (5-LO), the key enzyme in the biosynthesis of LTs. In this study, we describe the design and synthesis of CAPE analogs as radical scavengers and 5-LO inhibitors. Caffeic esters bearing propargyl and allyl linkers between the caffeoyl and aryl moieties (4a-i and 5a-i, respectively) were synthesized by Sonogashira and Heck cross-coupling reactions to probe the effects of flexibility and aryl substitution on 5-LO inhibition. Caffeoyl alcohol and ethers (6, 7a-b) as well as caffeoyl aldehyde and ketones (8a-e) were synthesized to elucidate the importance of the ester linkage for inhibitory activity. All tested compounds proved to be good radical scavengers (IC

Topics: Caffeic Acids; Carbon-13 Magnetic Resonance Spectroscopy; Free Radical Scavengers; HEK293 Cells; Humans; Lipoxygenase Inhibitors; Mass Spectrometry; Molecular Docking Simulation; Neutrophils; Phenylethyl Alcohol; Proton Magnetic Resonance Spectroscopy; Structure-Activity Relationship; Thapsigargin

The increase of cytoplasmic Ca2+ concentration (Delta[Ca2+]c) in response to antigenic stimulation is a critical step of signals activating immune responses. In addition, the voltage-gated K+ channels (Kv) in T lymphocytes draw attention as an effective target of immune-modulation. Caffeic acid phenethyl ester (CAPE), an active component of propolis, shows strong anti-inflammatory effects and T cell suppression. Although various mechanisms have been suggested for the action of CAPE, the effects of CAPE on intracellular Ca2+ signaling and ion channels are unknown. Here we investigated the effects of CAPE on Delta[Ca2+](c), Ca2+-release activated Ca2+ current (I(CRAC)), and Kv current (I(Kv)) in Jurkat T cells, and on Ca2+-activated K+ channel current (I(SK4)) overexpressed in HEK-293 cells. I(CRAC) was induced by dialyzing T cells and Orai1/STIM1 overexpressing HEK293 cells with InsP(3)/BAPTA-containing pipette solution. CAPE concentration-dependently decreased both T cell receptor (CD3)- and thapsigargin-induced Delta[Ca2+](c). The phosphorylation of PLCgamma(1) by CD3 stimulation was not affected by CAPE. I(CRAC) was almost completely blocked by 25 microM CAPE. CAPE also inhibited the I(Kv) and I(SK4). Albeit the strong inhibition of Ca2+ influx via CRAC, the suppression of IL-2 secretion by CAPE was similarly observed in human peripheral T cells when the CRAC pathway was circumvented by ionomycin. Although the unspecific inhibition of ion channels by CAPE suggested an intriguing mechanism, the effects of CAPE on signaling pathways other than I(CRAC) seem to play dominant roles in the immunomodulation by CAPE.

Topics: Caffeic Acids; Calcium; Calcium Signaling; CD28 Antigens; CD3 Complex; Cell Line; Chelating Agents; Dose-Response Relationship, Drug; Egtazic Acid; Electrophysiology; Humans; Inositol 1,4,5-Trisphosphate; Interleukin-2; Ionomycin; Jurkat Cells; Kidney; Patch-Clamp Techniques; Phenylethyl Alcohol; Phytohemagglutinins; Potassium Channels, Voltage-Gated; T-Lymphocytes; Thapsigargin; Time Factors