Exposure of fibrinogen and thrombin to nitric oxide donor ProliNONOate affects fibrin clot propertiesHelms, Christine C.a; Kapadia, Shannona; Gilmore, Anne C.a; Lu, Zhexia; Basu, Swatib,c; Kim-Shapiro, Daniel B.b,cBlood Coagulation & Fibrinolysis: July 2017 - Volume 28 - Issue 5 - p 356–364 doi: 10.1097/MBC.0000000000000602 ORIGINAL ARTICLES Buy Abstract Author InformationAuthors Article MetricsMetrics Fibrin fibers form the structural backbone of blood clots. The structural properties of fibrin clots are highly dependent on formation kinetics. Environmental factors such as protein concentration, pH, salt, and protein modification, to name a few, can affect fiber kinetics through altered fibrinopeptide release, monomer association, and/or lateral aggregation. The objective of our study was to determine the effect of thrombin and fibrinogen exposed to nitric oxide on fibrin clot properties. ProliNONOate (5 μmol/l) was added to fibrinogen and thrombin before clot initiation and immediately following the addition of thrombin to the fibrinogen solution. Resulting fibrin fibers were probed with an atomic force microscope to determine their diameter and extensibility and fibrin clots were analyzed for clot density using confocal microscopy. Fiber diameters were also determined by confocal microscopy and the rate of clot formation was recorded using UV-vis spectrophotometry. Protein oxidation and S-nitrosation was determined by UV-vis, ELISA, and chemiluminescence. The addition of ProliNONOate to fibrinogen or thrombin resulted in a change in clot structure. ProliNONOate exposure produced clots with lower fiber density, thicker fibers, and increased time to maximum turbidity. The effect of the exposure of nitric oxide to thrombin and fibrinogen were measured independently and indicated that each plays a role in altering clot properties. We detected thrombin S-nitrosation and protein carbonyl formation after nitric oxide exposure. Our study reveals a regulation of fibrin clot properties by nitric oxide exposure and suggests a role of peroxynitrite in oxidative modifications of the proteins. These results relate nitric oxide bioavailability and oxidative stress to altered clot properties. aDepartment of Physics, University of Richmond, Richmond, Virginia bDepartment of Physics cTranslational Science Center, Wake Forest University, Winston-Salem, North Carolina, USA Correspondence to Christine C. Helms, Department of Physics, University of Richmond, 28 Westhampton Way, Richmond, VA 23173, USA Tel: +1 804 289 8256; fax: +1 804 484 1542; e-mail: firstname.lastname@example.org Received 10 May, 2016 Revised 3 August, 2016 Accepted 12 August, 2016 Copyright © 2017 YEAR Wolters Kluwer Health, Inc. All rights reserved.