title: Plumericin inhibits proliferation of vascular smooth muscle cells by blocking STAT3 signaling via S-glutathionylation.
abstract: The etiology of atherosclerosis and restenosis involves aberrant inflammation and proliferation, rendering compounds with both anti-inflammatory and anti-mitogenic properties as promising candidates for combatting vascular diseases. A recent study identified the iridoid plumericin as a new scaffold inhibitor of the pro-inflammatory NF-κB pathway in endothelial cells. We here examined the impact of plumericin on the proliferation of primary vascular smooth muscle cells (VSMC). Plumericin inhibited serum-stimulated proliferation of rat VSMC. It arrested VSMC in the G1/G0-phase of the cell cycle accompanied by abrogated cyclin D1 expression and hindered Ser 807/811-phosphorylation of retinoblastoma protein. Transient depletion of glutathione by the electrophilic plumericin led to S-glutathionylation as well as hampered Tyr705-phosphorylation and activation of the transcription factor signal transducer and activator of transcription 3 (Stat3). Exogenous addition of glutathione markedly prevented this inhibitory effect of plumericin on Stat3. It also overcame downregulation of cyclin D1 expression and the reduction of biomass increase upon serum exposure. This study revealed an anti-proliferative property of plumericin towards VSMC which depends on plumericin's thiol reactivity and S-glutathionylation of Stat3. Hence, plumericin, by targeting at least two culprits of vascular dysfunction -inflammation and smooth muscle cell proliferation -might become a promising electrophilic lead compound for vascular disease therapy.
authors: Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
authors: Elke H
authors: EH
authors: Heiss
authors: Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
authors: Rongxia
authors: R
authors: Liu
authors: Institute of Pharmacy (Pharmacognosy) and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innsbruck, Austria.
authors: Birgit
authors: B
authors: Waltenberger
authors: Center for Physiology and Pharmacology, Institute for Vascular Biology and Thrombosis Research, Medical University of Vienna, Vienna, Austria.|Department of Zoology, University of Sargodha, Sargodha, Pakistan.
authors: Shafaat
authors: S
authors: Khan
authors: Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
authors: Daniel
authors: D
authors: Schachner
authors: Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
authors: Paul
authors: P
authors: Kollmann
authors: Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
authors: Kristin
authors: K
authors: Zimmermann
authors: Center for Physiology and Pharmacology, Institute for Vascular Biology and Thrombosis Research, Medical University of Vienna, Vienna, Austria.
authors: Muris
authors: M
authors: Cabaravdic
authors: Center for Physiology and Pharmacology, Institute for Vascular Biology and Thrombosis Research, Medical University of Vienna, Vienna, Austria.
authors: Pavel
authors: P
authors: Uhrin
authors: Institute of Pharmacy (Pharmacognosy) and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innsbruck, Austria.
authors: Hermann
authors: H
authors: Stuppner
authors: Center for Physiology and Pharmacology, Institute for Vascular Biology and Thrombosis Research, Medical University of Vienna, Vienna, Austria.
authors: Johannes M
authors: JM
authors: Breuss
authors: Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
authors: Atanas G
authors: AG
authors: Atanasov
authors: Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
authors: Verena M
authors: VM
authors: Dirsch
mesh_terms: D000818:Animals; D029062:Apocynaceae / Q000737:chemistry; D002478:Cells, Cultured; D019938:Cyclin D1 / Q000096:biosynthesis; D016193:G1 Phase / Q000187:drug effects*; D005978:Glutathione / Q000378:metabolism*; D007192:Indenes / Q000737:chemistry / Q000494:pharmacology*; D039823:Iridoids / Q000737:chemistry / Q000494:pharmacology*; D009131:Muscle, Smooth, Vascular / Q000378:metabolism* / Q000473:pathology; D032389:Myocytes, Smooth Muscle / Q000378:metabolism* / Q000473:pathology; D011499:Protein Processing, Post-Translational / Q000187:drug effects*; D051381:Rats; D016192:Resting Phase, Cell Cycle / Q000187:drug effects*; D050796:STAT3 Transcription Factor / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects*
chemical_list: C530106:Ccnd1 protein, rat; D007192:Indenes; D039823:Iridoids; D050796:STAT3 Transcription Factor; C494088:Stat3 protein, rat; D019938:Cyclin D1; D005978:Glutathione; C068511:plumericin