title: Quercetin attenuates warfarin-induced vascular calcification in vitro independently from matrix Gla protein.
abstract: Warfarin can stimulate vascular calcification in vitro via activation of β-catenin signaling and/or inhibition of matrix Gla protein (MGP) carboxylation. Calcification was induced in vascular smooth muscle cells (VSMCs) with therapeutic levels of warfarin in normal calcium and clinically acceptable phosphate levels. Although TGF/BMP and PKA pathways are activated in calcifying VSMCs, pharmacologic analysis reveals that their activation is not contributory. However, β-catenin activity is important because inhibition of β-catenin with shRNA or bioflavonoid quercetin prevents calcification in primary human VSMCs, rodent aortic rings, and rat A10 VSMC line. In the presence of quercetin, reactivation of β-catenin using the glycogen synthase kinase-3β (GSK-3β) inhibitor LiCl restores calcium accumulation, confirming that quercetin mechanism of action hinges on inhibition of the β-catenin pathway. Calcification in VSMCs induced by 10 μm warfarin does not associate with reduced levels of carboxylated MGP, and inhibitory effects of quercetin do not involve induction of MGP carboxylation. Further, down-regulation of MGP by shRNA does not alter the effect of quercetin. These results suggest a new β-catenin-targeting strategy to prevent vascular calcification induced by warfarin and identify quercetin as a potential therapeutic in this pathology.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA.
authors.forename: Kelly E
authors.initials: KE
authors.lastname: Beazley
authors.forename: Saman
authors.initials: S
authors.lastname: Eghtesad
authors.forename: Maria V
authors.initials: MV
authors.lastname: Nurminskaya
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D001011:Aorta / Q000473:pathology; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000378:metabolism*; D020869:Gene Expression Profiling; D017930:Genes, Reporter; D066298:In Vitro Techniques; D008156:Luciferases / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000166:cytology; D011794:Quercetin / Q000494:pharmacology*; D034741:RNA, Small Interfering / Q000378:metabolism; D051381:Rats; D015398:Signal Transduction; D061205:Vascular Calcification / Q000139:chemically induced*; D014859:Warfarin / Q000494:pharmacology*; D051176:beta Catenin / Q000378:metabolism; D000097568:Matrix Gla Protein
chemical_list: D000975:Antioxidants; D002135:Calcium-Binding Proteins; D017868:Cyclic AMP-Dependent Protein Kinases; D016326:Extracellular Matrix Proteins; D008156:Luciferases; D011794:Quercetin; D034741:RNA, Small Interfering; D014859:Warfarin; D051176:beta Catenin; D000097568:Matrix Gla Protein