title: Silymarin Constituents Enhance ABCA1 Expression in THP-1 Macrophages.
abstract: Silymarin is a hepatoprotective mixture of flavonolignans and flavonoids extracted from the seeds of milk thistle (Silybum marianum L. Gaertn). This study investigates the effect of major bioactive constituents from silymarin, silybin A, silybin B, isosilybin A, isosilybin B, silydianin, silychristin, isosilychristin, and taxifolin, on the expression of ABCA1, an important cholesterol efflux transporter, in THP-1-derived macrophages. Four of the studied compounds, isosilybin A, silybin B, silychristin and isosilychristin, were found to significantly induce ABCA1 protein expression without affecting cell viability. Moreover, isosilybin A, a partial PPARγ agonist, was found to promote cholesterol efflux from THP-1 macrophages in a concentration-dependent manner. These findings first show ABCA1 protein up-regulating activity of active constituents of silymarin and provide new avenues for their further study in the context of cardiovascular disease.
authors.affiliation: Department of Pharmacognosy, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria. limei.wang@univie.ac.at.
authors.forename: Limei
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Pharmacognosy, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria. a0800134@unet.univie.ac.at.
authors.forename: Susanne
authors.initials: S
authors.lastname: Rotter
authors.affiliation: Department of Pharmacognosy, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria. angela.ladurner@univie.ac.at.
authors.forename: Angela
authors.initials: A
authors.lastname: Ladurner
authors.affiliation: Department of Pharmacognosy, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria. elke.heiss@univie.ac.at.
authors.forename: Elke H
authors.initials: EH
authors.lastname: Heiss
authors.affiliation: Department of Chemistry &amp; Biochemistry, University of North Carolina at Greensboro, Greensboro, NC 27402, USA. n_oberli@uncg.edu.
authors.forename: Nicholas H
authors.initials: NH
authors.lastname: Oberlies
authors.affiliation: Department of Pharmacognosy, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria. verena.dirsch@univie.ac.at.
authors.forename: Verena M
authors.initials: VM
authors.lastname: Dirsch
authors.affiliation: Department of Pharmacognosy, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria. atanas.atanasov@univie.ac.at.
authors.forename: Atanas G
authors.initials: AG
authors.lastname: Atanasov
mesh_terms: D064286:ATP Binding Cassette Transporter 1 / Q000378:metabolism*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D008264:Macrophages / Q000166:cytology / Q000378:metabolism*; D012838:Silymarin / Q000737:chemistry / Q000494:pharmacology*
chemical_list: C577836:ABCA1 protein, human; D064286:ATP Binding Cassette Transporter 1; D012838:Silymarin
keywords: ABCA1; cholesterol efflux; flavonolignans; isosilybin A; macrophages; silymarin