1. ¹Department of Dermatology and Cutaneous Biology, Jefferson Medical College and Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
2. ²Department of Biochemistry and Molecular Biology, Jefferson Medical College and Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania, USA

Correspondence: Dr Jouni Uitto, Department of Dermatology and Cutaneous Biology, Thomas Jefferson University, 233 South 10th Street, Suite 450 BLSB, Philadelphia, Pennsylvania 19107, USA. E-mail: Jouni.Uitto@jefferson.edu

Received 6 August 2007; Revised 12 September 2007; Accepted 12 September 2007; Published online 29 November 2007.

Abstract

Pseudoxanthoma elasticum (PXE), a multisystem disorder characterized by ectopic mineralization of soft connective tissues, is caused by mutations in the ABCC6 gene. The pathomechanistic details of the mineralization process are largely unknown, but oxidative stress has been suggested to play a role. In this study, we tested Abcc6^-/- mice, which serve as a model of PXE, for markers of the oxidative stress in the liver and serum. The total antioxidant capacity as well as markers of protein oxidation and lipid peroxidation suggested the presence of chronic oxidative stress. Feeding these mice for 5 months with a diet supplemented with antioxidants (vitamins C and E, selenium, and N-acetylcysteine) countered the oxidative stress but did not modify the ectopic mineralization process. These results suggest that the Abcc6^-/- mice suffer from chronic oxidative stress but this does not contribute to connective tissue mineralization, the hallmark of PXE.