Misregulation of gene expression in the redox-sensitive NF-κb-dependent limb outgrowth pathway by thalidomide
Version of Record online: 5 SEP 2002
Copyright © 2002 Wiley-Liss, Inc.
Volume 225, Issue 2, pages 186–194, October 2002
How to Cite
Hansen, J. M., Gong, S.-G., Philbert, M. and Harris, C. (2002), Misregulation of gene expression in the redox-sensitive NF-κb-dependent limb outgrowth pathway by thalidomide. Dev. Dyn., 225: 186–194. doi: 10.1002/dvdy.10150
- Issue online: 19 SEP 2002
- Version of Record online: 5 SEP 2002
- Manuscript Accepted: 22 JUL 2002
- Manuscript Received: 26 NOV 2001
- redox status;
- oxidative stress;
Thalidomide is known to induce oxidative stress, but mechanisms have not been described through which oxidative stress could contribute to thalidomide-induced terata. Oxidative stress modulates intracellular glutathione (GSH) and redox status and can perturb redox-sensitive processes, such as transcription factor activation and/or binding. Nuclear factor-kappa B (NF-κB), a redox-sensitive transcription factor involved in limb outgrowth, may be modulated by thalidomide-induced redox shifts. Thalidomide-resistant Sprague-Dawley rat embryos (gestation day [GD] 13) treated with thalidomide in utero showed no changes in GSH distribution in the limb but thalidomide-sensitive New Zealand White rabbit embryos (GD 12) showed selective GSH depletion in the limb bud progress zone (PZ). NF-κB and regulatory genes that initiate and maintain limb outgrowth and development, such as Twist and Fgf-10, are selectively expressed in the PZ. Green fluorescent protein (GFP) reporter vectors containing NF-κB binding promoter sites were transfected into both rat and rabbit limb bud cells (LBCs). Treatment with thalidomide caused a preferential decrease in GFP expression in rabbit LBCs but not in rat LBCs. N-acetylcysteine and α-N-t-phenylbutyl nitrone (PBN), a free radical trapping agent, rescued GFP expression in thalidomide-treated cultures compared with cultures that received thalidomide only. In situ hybridization showed a preferential decrease in Twist, Fgf-8, and Fgf-10 expression after thalidomide treatment (400 mg/kg per day) in rabbit embryos. Expression in rat embryos was not affected. Intravenous cotreatment with PBN and thalidomide (gavage) in rabbits restored normal patterns and localization of Twist, Fgf-8, and Fgf-10 expression. These findings show that NF-κB binding is diminished due to selective thalidomide-induced redox changes in the rabbit, resulting in the significant attenuation of expression of genes necessary for limb outgrowth. © 2002 Wiley-Liss, Inc.