title: First combined in vivo X-ray tomography and high-resolution molecular electron paramagnetic resonance (EPR) imaging of the mouse knee joint taking into account the disappearance kinetics of the EPR probe.
abstract: Although laboratory data clearly suggest a role for oxidants (dioxygen and free radicals derived from dioxygen) in the pathogenesis of many age-related and degenerative diseases (such as arthrosis and arthritis), methods to image such species in vivo are still very limited. This methodological problem limits physiopathologic studies about the role of those species in vivo, the effects of their regulation using various drugs, and the evaluation of their levels for diagnosis of degenerative diseases. In vivo electron paramagnetic resonance (EPR) imaging and spectroscopy are unique, noninvasive methods used to specifically detect and quantify paramagnetic species. However, two problems limit their application: the anatomic location of the EPR image in the animal body and the relative instability of the EPR probes. Our aim is to use EPR imaging to obtain physiologic and pathologic information on the mouse knee joint. This article reports the first in vivo EPR image of a small tissue, the mouse knee joint, with good resolution (≈ 160 μm) after intra-articular injection of a triarylmethyl radical EPR probe. It was obtained by combining EPR and x-ray micro-computed tomography for the first time and by taking into account the disappearance kinetics of the EPR probe during image acquisition to reconstruct the image. This multidisciplinary approach opens the way to high-resolution EPR imaging and local metabolism studies of radical species in vivo in different physiologic and pathologic situations.
authors.affiliation: CNRS UMR 8601, Université Paris Descartes, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Bézière
authors.forename: Christophe
authors.initials: C
authors.lastname: Decroos
authors.forename: Karen
authors.initials: K
authors.lastname: Mkhitaryan
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Kish
authors.forename: Frédéric
authors.initials: F
authors.lastname: Richard
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Bigot-Marchand
authors.forename: Sylvain
authors.initials: S
authors.lastname: Durand
authors.forename: Florence
authors.initials: F
authors.lastname: Cloppet
authors.forename: Caroline
authors.initials: C
authors.lastname: Chauvet
authors.forename: Marie-Thérèse
authors.initials: MT
authors.lastname: Corvol
authors.forename: François
authors.initials: F
authors.lastname: Rannou
authors.forename: Yun
authors.initials: Y
authors.lastname: Xu-Li
authors.forename: Daniel
authors.initials: D
authors.lastname: Mansuy
authors.forename: Fabienne
authors.initials: F
authors.lastname: Peyrot
authors.forename: Yves-Michel
authors.initials: YM
authors.lastname: Frapart
mesh_terms: D000818:Animals; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D007700:Kinetics; D007719:Knee Joint / Q000000981:diagnostic imaging*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D013113:Spin Labels; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D013113:Spin Labels