Xanthine oxidase mediates cytokine-induced, but not hormone-induced bone resorption


Kanczler, Janos M., Millar, Timothy M., Bodamyali, Tulin, Blake, David R. and Stevens, Cliff R. (2003) Xanthine oxidase mediates cytokine-induced, but not hormone-induced bone resorption. Free Radical Research, 37, (2), 179-187. (doi:10.1080/1071576021000040673).

Download

Full text not available from this repository.

Description/Abstract

Reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) have been implicated as mediators of osteoclastic bone resorption. Xanthine oxidase (XO) a ubiquitous enzyme is widely known for its production of these ROS. We therefore evaluated the potential of XO as a source of ROS in cytokine-and hormone-induced bone resorption. XO activity in rat calvarial osteoblasts was found to be significantly elevated upon stimulation by the cytokines, TNFalpha and IL-1beta. These cytokines also caused a dose related increase in bone resorption of mouse calvariae, which was significantly inhibited by catalase (10 IU/ml). Allopurinol, the competitive inhibitor of XO, also caused a dose related (1-50 microM) inhibition of TNFalpha (20 ng/ml) and (0.01-10 microM) IL-1beta (50 IU/ml)-induced bone resorption, respectively. PTH- and 1,25-(OH)2 Vitamin D3-induced bone resorption could also be inhibited by catalase (100 IU/ml) but was unaffected by allopurinol, indicating that another mediator, other than XO, is required for hormone-induced bone resorption. These results demonstrate, that modulation of the redox balance in the bone microenvironment, which contains XO, can affect the bone resorbing process. Therefore, XO may play a pivotal role in cytokine-induced bone resorption and, if manipulated appropriately, could show a therapeutic benefit in inflammatory bone disorders such as RA.

Item Type: Article
ISSNs: 1071-5762 (print)
Related URLs:
Keywords: xanthine oxidase, bone resorption, cytokines, hydrogen peroxide
Subjects: Q Science > QR Microbiology
Divisions: University Structure - Pre August 2011 > School of Medicine > Infection, Inflammation and Repair
ePrint ID: 44322
Date Deposited: 23 Feb 2007
Last Modified: 27 Mar 2014 18:28
URI: http://eprints.soton.ac.uk/id/eprint/44322

Actions (login required)

View Item View Item