|
|
|
|
A more recent version of this article appeared on March 1, 2008
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Submitted on October 4, 2007
Revised on December 26, 2007
Accepted on January 4, 2008

,
*Department of Microbiology and Molecular Genetics, University of Texas Medical School, Houston, TX 77030;
Department of Biochemistry, Molecular Biology and Cell Biology, Rice Institute for Biomedical Research, Northwestern University, Evanston, IL 60208;
Department of Chemistry, Department of Biochemistry, Molecular Biology, and Cell Biology, and the Center for Drug Discovery and Chemical Biology, Northwestern University, Evanston, IL 60208
Monitoring Editor: Peter Walter
Stress response pathways allow cells to sense and respond to environmental changes and adverse pathophysiological states. Pharmacologic modulation of cellular stress pathways has implications in the treatment of human diseases including neurodegenerative disorders, cardiovascular disease and cancer. The quinone methide triterpene celastrol, derived from a traditional Chinese medicinal herb, has numerous pharmacological properties and is a potent activator of the mammalian heat shock transcription factor HSF1. However, its mode of action and spectrum of cellular targets are poorly understood. We show here that celastrol activates Hsf1 in S. cerevisiae at a similar effective concentration seen in mammalian cells. Transcriptional profiling revealed that celastrol treatment induces a battery of oxidant defense genes in addition to heat shock genes. Celastrol activated the yeast Yap1 oxidant defense transcription factor via the carboxy-terminal redox center that responds to electrophilic compounds. Antioxidant response genes were likewise induced in mammalian cells, demonstrating that the activation of two major cell stress pathways by celastrol is conserved. We report that celastrols biological effects, including inhibition of glucocorticoid receptor activity, can be blocked by the addition of excess free thiol, suggesting a chemical mechanism for biological activity based on modification of key reactive thiols by this natural product.
These authors contributed equally to this work.
Address correspondence to:
Kevin A. Morano (kevin.a.morano{at}uth.tmc.edu)
This article has been cited by other articles:
![]() |
R. I. Morimoto Proteotoxic stress and inducible chaperone networks in neurodegenerative disease and aging Genes & Dev., June 1, 2008; 22(11): 1427 - 1438. [Abstract] [Full Text] [PDF] |
||||