Combining μX-ray fluorescence, μXANES and μXRD to shed light on Zn2+ cations in cartilage and meniscus calcifications.

Abstract

We aimed to examine the presence of Zn, a trace element, in osteoarthritis (OA) cartilage and meniscus from patients undergoing total knee joint replacement for primary OA. We mapped Ca(2+) and Zn(2+) at the mesoscopic scale by X-ray fluorescence microanalysis (μX-ray) to determine the spatial distribution of the 2 elements in cartilage, μX-ray absorption near edge structure spectroscopy to identify the Zn species, and μX-ray diffraction to determine the chemical nature of the calcification. Fourier transform infrared spectroscopy was used to determine the chemical composition of cartilage and meniscus. Ca(2+) showed a heterogeneous spatial distribution corresponding to the calcifications within cartilage (or meniscus) or at their surface. At least 2 Zn(2+) species were present: the first may correspond to Zn embedded in protein (different Zn metalloproteins are known to prevent calcification in biological tissues), and the second may be associated with a Zn trap in or at the surface of the calcification. Calcification present in OA cartilage may significantly modify the spatial distribution of Zn; part of the Zn may be trapped in the calcification and may alter the associated biological function of Zn metalloproteins.

• Authors: Arnaud Dessombz, Christelle Nguyen, Hang-Korng Ea, Stephan Rouzière, Eddy Foy, Didier Hannouche, Solene Réguer, Frederic-Emmanuel Picca, Dominique Thiaudière, Frédéric Lioté, Michel Daudon, Dominique Bazin
• Journal: Journal of trace elements in medicine and biology : organ of the Society for Minerals and Trace Elements (GMS) (J Trace Elem Med Biol) Vol. 27 Issue 4 Pg. 326-33 (Oct 2013) ISSN: 1878-3252 [Electronic] Germany
• PMID: 23582484 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2013 Elsevier GmbH. All rights reserved.

Chemical References

• Cations
• Zinc

Topics

• Aged
• Cartilage, Articular (chemistry, pathology)
• Cations (analysis)
• Humans
• Knee Joint (chemistry, pathology)
• Light
• Male
• Menisci, Tibial (chemistry, pathology)
• Osteoarthritis (pathology)
• Spectrometry, X-Ray Emission
• X-Ray Absorption Spectroscopy
• X-Ray Diffraction
• Zinc (analysis)