Molecular phenotyping of a test compound (small-molecule neurotransmitter receptor antagonist) in primary human hepatocytes
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE64588 | GEO | 2015/07/01
SECONDARY ACCESSION(S): PRJNA271358
REPOSITORIES: GEO
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Project description:Expression profiles of 917 pathway repoter genes were determined by AmpliSeq-RNA in primary human hepatocytes treated with Diclofenac and a test compound 3 hours after treatment. Vehicle control, diclofenac, and three doses of the test compound (small-molecule neurotransmitter receptor antagonist) were applied to three primary cell lines, with three biological replicates in each group. In some treatment groups read-outs were only available for two samples. All together 41 samples were profiled.
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Project description:Diclofenac is a widely used analgesic drug that can cause serious adverse drug reactions. We used Saccharomyces cerevisiae as model eukaryote to elucidate the molecular mechanisms of diclofenac toxicity and resistance. Although most yeast cells died during initial diclofenac treatment, some survived and started growing again. Microarray analysis of the adapted cells identified three major processes involved in diclofenac detoxification and tolerance. Especially pleiotropic drug resistance genes and genes under control of Rlm1p, a transcription factor in the protein kinase C (PKC) pathway, were upregulated in diclofenac-adapted cells. Genes involved in ribosome biogenesis and rRNA processing were downregulated, as well as zinc-responsive genes.
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Project description:In a search for small molecule antagonists of heparan sulfate, we examined the activity of bis-2-methyl-4-amino-quinolyl-6-carbamide, also known as surfen. Fluorescence-based titrations indicated that surfen bound to glycosaminoglycans, and the extent of binding increased according to charge density in the order heparin > dermatan sulfate > heparan sulfate > chondroitin sulfate. All charged groups in heparin (N-sulfates, O-sulfates, and carboxyl groups) contributed to binding, consistent with the idea that surfen interacted electrostatically. Surfen neutralized the anticoagulant activity of both unfractionated and low molecular weight heparins and inhibited enzymatic sulfation and degradation reactions in vitro. Addition of surfen to cultured cells blocked FGF2-binding and signaling that depended on cell surface heparan sulfate and prevented both FGF2- and VEGF(165)-mediated sprouting of endothelial cells in Matrigel. Surfen also blocked heparan sulfate-mediated cell adhesion to the Hep-II domain of fibronectin and prevented infection by HSV-1 that depended on glycoprotein D interaction with heparan sulfate. These findings demonstrate the feasibility of identifying small molecule antagonists of heparan sulfate and raise the possibility of developing pharmacological agents to treat disorders that involve glycosaminoglycan-protein interactions.
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