- 作者：H.T. ; Kokkonen&dagger ; ; ; &Dagger ; ; ; harri.kokkonen@uef.fi ; J. ; Mä ; kelä ; &dagger ; ; K.A.M. ; Kulmala&dagger ; ; L. ; Rieppo&dagger ; ; J.S. ; Jurvelin&dagger ; ; V. ; Tiitu§ ; ; ; ?/sup> ; H.M. ; Karjalainen§ ; ; R.K. ; Korhonen&dagger ; ; V. ; Kovanen¶ ; ; J. ; Tö ; yrä ; s&dagger ; ; ; &Dagger ;
- 关键词：Cartilage aging ; Cartilage injury ; Contrast agent ; Diffusion ; Computed tomography ; Cross-linking
- 刊名：Osteoarthritis and Cartilage
- 出版年：2011
- 出版时间：October 2011
- 年：2011
- 卷：19
- 期：10
- 页码：1190-1198
- 全文大小：570 K
Summary
Objective
The effect of threose-induced collagen cross-linking on the mechanical and diffusive properties of cartilage was investigated in?vitro. In particular, we investigated the potential of Contrast Enhanced Computed Tomography (CECT) to detect changes in articular cartilage after increased collagen cross-linking, which is an age-related phenomenon.Methods
Osteochondral plugs (? = 6.0 mm, n = 28) were prepared from intact bovine patellae (n = 7). Two of the four adjacent samples, prepared from each patella, were treated with threose to increase the collagen cross-linking, while the other two specimen served as paired controls. One sample pair was mechanically tested and then mechanically injured using a material testing device. Contrast agent [ioxaglate (Hexabrix?] diffusion was imaged in the other specimen pair for 25 h using CECT. Water fraction, collagen and proteoglycan content, collagen network architecture and the amount of cross-links [hydroxylysyl pyridinoline (HP), lysyl pyridinoline (LP) and pentosidine (Pent)] of the samples were also determined.
Results
Cartilage collagen cross-linking, both Pent and LP, were significantly (P < 0.001) increased due to threose treatment. CECT could detect the increased cross-links as the contrast agent penetration and the diffusion flux were significantly (P < 0.05) lower in the threose treated than in untreated samples. The equilibrium modulus (+164 % , P < 0.05) and strain dependent dynamic modulus (+47 % , P < 0.05) were both significantly greater in the threose treated samples than in reference samples, but there was no association between the initial dynamic modulus and the threose treatment. The water fraction, proteoglycan and collagen contents, as well as collagen architecture, were not significantly altered by the threose treatment.
Conclusions
To conclude, the CECT technique was found to be sensitive at detecting changes in cartilage tissue due to increased collagen cross-linking. This is important since increased cross-linking has been proposed to be related to the increased injury susceptibility of tissue.