title: Autumnalamide targeted proteins of the immunophilin family.
abstract: Previous works with autumnalamide reported that Store Operated Calcium (SOC) channels were blocked through mitochondrial modulation. In the present paper we studied the effect of autumnalamide on ionomycin Ca2+fluxes. Thus, autumnalamide did not modify ionomycin-sensitive intracellular pools while the ionomycin-induced Ca2+influx was blocked with similar potency whether the incubation was done before or after ionomycin-sensitive pools depletion. Nevertheless, autumnalamide was not able to inhibit ionomycin-induced Ca2+influx once the membrane channels were activated. Moreover, the compound efficiently inhibited flufenamic acid (FFA) Ca2+release induced in this organelle but no the next influx. Since in previous work the effect of autumnalamide was inhibited by cyclosporine A (CsA), structures that target this drug were studied. Therefore, the affinity of autumnalamide for cyclophilin D (Cyp D) was examined. The KDobtained for Cyp D- autumnalamide was 1.51±1.399. Moreover, the KDfor Cyp A- autumnalamide was calculated. The peptide had a similar order of Cyp A binding affinity than CsA (8.08±1.23 and 6.85±1.1μM respectively). After testing autumnalamide-binding capacity for Cyp A, the activity of this compound on Cyp A pathway was tested. Thus, the effect on interleukin (IL)-2 release on activated T-lymphocytes was checked. Autumnalamide was able to reduce IL-2 levels near to T cells in resting conditions. Next, the effect over calcineurin and NFATc1 was also evaluated. While CsA inhibits both calcineurin and NFATc1, autumnalamide did not produce any effect. From these results we can conclude that, autumnalamide targeted mitochondrion and prevent T-cells from IL-2 production through the modulation of SOC Ca2+channels.
authors.affiliation: Departamento de Farmacología, Facultad de Veterinaria, Universidad de Santiago de Compostela, Lugo 27002, Spain. Electronic address: jonandoni.sanchez@rai.usc.es.
authors.forename: Jon Andoni
authors.initials: JA
authors.lastname: Sánchez
authors.affiliation: Departamento de Farmacología, Facultad de Veterinaria, Universidad de Santiago de Compostela, Lugo 27002, Spain. Electronic address: amparo.alfonso@usc.es.
authors.forename: Amparo
authors.initials: A
authors.lastname: Alfonso
authors.affiliation: Geoazur, UMR Université Nice Sophia Antipolis-CNRS-IRD-OCA, 250 rue Albert Einstein, 06560, Valbonne, France; Marine Biodiscovery, School of Chemistry, National University of Ireland Galway, University Road, Galway, Ireland. Electronic address: olivier.thomas@nuigalway.ie.
authors.forename: Olivier P
authors.initials: OP
authors.lastname: Thomas
authors.affiliation: Departamento de Farmacología, Facultad de Veterinaria, Universidad de Santiago de Compostela, Lugo 27002, Spain. Electronic address: Luis.Botana@usc.es.
authors.forename: Luís M
authors.initials: LM
authors.lastname: Botana
mesh_terms: D002118:Calcium / Q000378:metabolism; D002121:Calcium Channel Blockers / Q000737:chemistry / Q000494:pharmacology; D015220:Calcium Channels / Q000378:metabolism; D020013:Calcium Signaling / Q000187:drug effects; D002460:Cell Line; D002478:Cells, Cultured; D006801:Humans; D020104:Immunophilins / Q000378:metabolism*; D015759:Ionomycin / Q000494:pharmacology; D008024:Ligands; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D010456:Peptides, Cyclic / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D011485:Protein Binding; D013601:T-Lymphocytes / Q000378:metabolism
chemical_list: D002121:Calcium Channel Blockers; D015220:Calcium Channels; D008024:Ligands; D010456:Peptides, Cyclic; C000593555:autumnalamide; D015759:Ionomycin; D020104:Immunophilins; D002118:Calcium
keywords: Ca(2+); Cyclophilin; Mitochondria; Phormidium autumnale; SOC channels