Papers by Khalid Abdelazeem
Clinical Cancer Research, Sep 14, 2023
Dissertation ist gesperrt bis 03. Dezember 2022 !
Cellular Physiology and Biochemistry, 2017
This article is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 I... more This article is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND) (http://www.karger.com/Services/OpenAccessLicense). Usage and distribution for commercial purposes as well as any distribution of modified material requires written permission.
British Journal of Pharmacology, Jul 21, 2022
Cellular Physiology and Biochemistry, 2017
This article is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 I... more This article is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND) (http://www.karger.com/Services/OpenAccessLicense). Usage and distribution for commercial purposes as well as any distribution of modified material requires written permission.
British Journal of Pharmacology
Scientific Reports, 2021
Inflammation is a natural defense process of the innate immune system, associated with the releas... more Inflammation is a natural defense process of the innate immune system, associated with the release of proinflammatory cytokines such as interleukin-1β, interleukin-6, interleukin-12 and TNFα; and enzymes including iNOS through the activation and nuclear translocation of NF-κB p65 due to the phosphorylation of IκBα. Regulation of intracellular Ca2+ is considered a promising strategy for the prevention of reactive oxygen species (ROS) production and accumulation of DNA double strand breaks (DSBs) that occurs in inflammatory-associated-diseases. Among the metabolites of ellagitannins that are produced in the gut microbiome, urolithin A (UA) has received an increasing attention as a novel candidate with anti-inflammatory and anti-oxidant effects. Here, we investigated the effect of UA on the suppression of pro-inflammatory molecules and NF-κB activation by targeting TLR4 signalling pathway. We also identified the influence of UA on Ca2+ entry, ROS production and DSBs availability in mur...
Cellular Physiology and Biochemistry, 2017
Background: MicroRNAs (miRNAs) negatively regulate gene expression at a post-transcriptional leve... more Background: MicroRNAs (miRNAs) negatively regulate gene expression at a post-transcriptional level. Dicer, a cytoplasmic RNase III enzyme, is required for the maturation of miRNAs from precursor miRNAs. Dicer, therefore, is a critical enzyme involved in the biogenesis and processing of miRNAs. Several biological processes are controlled by miRNAs, including the regulation of T cell development and function. T cells generate reactive oxygen species (ROS) with parallel H+ extrusion accomplished by the Na+/H+-exchanger 1 (NHE1). The present study explored whether ROS production, as well as NHE1 expression and function are sensitive to the lack of Dicer (miRNAs deficient) and could be modified by individual miRNAs. Methods: CD4+ T cells were isolated from CD4 specific Dicer deficient (DicerΔ/Δ) mice and the respective control mice (Dicerfl/fl). Transcript and protein levels were quantified with RT-PCR and Western blotting, respectively. For determination of intracellular pH (pHi) cells ...
Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry, and pharmacology, Jan 27, 2017
Key properties of tumor cells include enhanced glycolytic flux with excessive consumption of gluc... more Key properties of tumor cells include enhanced glycolytic flux with excessive consumption of glucose and formation of lactate. As glycolysis is highly sensitive to cytosolic pH, maintenance of glycolysis requires export of H+ ions, which is in part accomplished by Na+/H+ exchangers, such as NHE1. The carrier is sensitive to oxidative stress. Growth of tumor cells could be suppressed by the polyphenol Ellagic acid, which is found in various fruits and vegetables. An effect of Ellagic acid on transport processes has, however, never been reported. The present study thus elucidated an effect of Ellagic acid on cytosolic pH (pHi), NHE1 transcript levels, NHE1 protein abundance, Na+/H+ exchanger activity, and lactate release. Experiments were performed in Ishikawa cells without or with prior Ellagic acid (20 µM) treatment. NHE1 transcript levels were determined by qRT-PCR, NHE1 protein abundance by Western blotting, pHi utilizing (2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluore...
Biochemical and Biophysical Research Communications, 2019
Placental growth factor (PlGF) is produced by tumor cells and stimulates tumor growth and metasta... more Placental growth factor (PlGF) is produced by tumor cells and stimulates tumor growth and metastasis in part by upregulation of hypoxia inducible factor HIF1a. Orchestration of tumor cell proliferation and migration involves oscillations of cytosolic Ca 2þ activity ([Ca 2þ ] i). The [Ca 2þ ] i oscillations could be accomplished by triggering of intracellular Ca 2þ release followed by store-operated Ca 2þ-entry (SOCE). Mechanisms accomplishing SOCE include the pore-forming ion channel unit Orai1 and its regulator STIM1. The present study explored whether PlGF influences the expression of Orai1 and STIM1, as well as SOCE and whether this effect impacts on HIF1a expression. To this end, ovary carcinoma cells were cultured for 24 h without and with PlGF (10 ng/ml). Orai1, STIM1 and HIF1a transcript levels were quantified utilizing RT-PCR and Orai1, STIM1 and HIF1a protein levels by Western blotting. [Ca 2þ ] i was estimated from Fura-2-fluorescence and SOCE from increase of [Ca 2þ ] i following Ca 2þ re-addition after Ca 2þ-store depletion with extracellular Ca 2þ removal and sarcoendoplasmatic Ca 2þ-ATPase (SERCA) inhibitor thapsigargin (1 mM). As a result, exposure of ovary carcinoma cells to PlGF was followed by a significant increase of Orai1 as well as STIM1 transcript and protein levels. PlGF significantly increased store-operated Ca 2þ-entry following re-addition of extracellular Ca 2þ , an effect virtually abrogated by Orai1 inhibitor MRS1845 (10 mM). PlGF further increased HIF1a transcript and protein levels, an effect again significantly blunted by MRS1845 (10 mM). In conclusion, PlGF upregulates expression of both, Orai1 and STIM1 thus enhancing store-operated Ca 2þ-entry with subsequent upregulation of HIF1a.
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Papers by Khalid Abdelazeem