title: Rutin stimulates sarcoplasmic reticulum Ca(2+)-ATPase activity (SERCA1) and protects SERCA1 from peroxynitrite mediated injury.
abstract: In this study we analyzed the protective action of the flavonoid rutin on peroxynitrite (ONOO(-)) mediated impairment of sarcoplasmic reticulum Ca(2+)-ATPase (SERCA1 isoform), especially related to posttranslational and conformational changes. Rutin concentration dependently protected ONOO(-) induced SERCA1 activity decrease with effective concentration EC50 of 18 ± 1.5 µM. Upon treatment with ONOO(-), this flavonoid also prevented SERCA1 from thiol group oxidation and significantly reduced tyrosine nitration and protein carbonyl formation. In the absence of ONOO(-), rutin (250 and 350 µM) stimulated SERCA1 activity at 2.1 mM [ATP] and 10 µM [Ca(2+)]free. According to changes in the kinetic parameters V max and K m with regard to [ATP], rutin (250 µM) increased the rate of enzyme catalysis and decreased the affinity of SERCA1 to ATP. FITC fluorescence decreased in the presence of rutin (150 and 250 µM), indicating conformational changes in the cytosolic ATP binding region of SERCA1. In silico study confirmed the binding of rutin in the cytosolic region of SERCA1, in the vicinity of the ATP binding site. Residue Glu183 localized within the conserved TGES loop was identified to play a key role in rutin-SERCA1 interaction (H-bond length of 1.7 Å), elucidating the ability of rutin to affect the affinity of SERCA1 to ATP. The binding of rutin in the proximity of Lys515 is likely to cause a decrease in FITC fluorescence.
authors.affiliation: Department of Biochemical Pharmacology, Institute of Experimental Pharmacology and Toxicology, Slovak Academy of Sciences, 841 04, Bratislava, Slovakia, janaviskupicova@gmail.com.
authors.forename: Jana
authors.initials: J
authors.lastname: Viskupicova
authors.forename: Miriam K
authors.initials: MK
authors.lastname: Strosova
authors.forename: Petronela
authors.initials: P
authors.lastname: Zizkova
authors.forename: Magdalena
authors.initials: M
authors.lastname: Majekova
authors.forename: Lubica
authors.initials: L
authors.lastname: Horakova
mesh_terms: D000818:Animals; D004353:Drug Evaluation, Preclinical; D005260:Female; D006860:Hydrogen Bonding; D007700:Kinetics; D062105:Molecular Docking Simulation; D016877:Oxidants / Q000494:pharmacology; D030421:Peroxynitrous Acid / Q000494:pharmacology; D011485:Protein Binding; D011499:Protein Processing, Post-Translational; D011817:Rabbits; D012431:Rutin / Q000494:pharmacology*; D012519:Sarcoplasmic Reticulum / Q000187:drug effects* / Q000201:enzymology; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases / Q000737:chemistry / Q000378:metabolism*
chemical_list: D016877:Oxidants; D030421:Peroxynitrous Acid; D012431:Rutin; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases