Binding of rapamycin analogs to calcium channels and FKBP52 contributes to their neuroprotective activities

Autor: Andrew R. Wood, Guy T. Carter, Edmund I. Graziani, Menelas N. Pangalos, Kevin Pong, Frank E. Koehn, Benfang Ruan, Ronald L. Magolda, Magid Abou-Gharbia, Robert A. Crozier, Flora Jow, Frann Bennett, Danni Liu, Mark R. Bowlby, Peter H. Reinhart, Xidong Feng, Mary Lynn T. Mercado, Leonard A. McDonald, Shi Liang, Yi Chen, Jerauld S. Skotnicki, Margaret M. Zaleska, David von Schack
Rok vydání: 2008
Předmět:
Zdroj: Proceedings of the National Academy of Sciences. 105:33-38
ISSN: 1091-6490
0027-8424
Popis: Rapamycin is an immunosuppressive immunophilin ligand reported as having neurotrophic activity. We show that modification of rapamycin at the mammalian target of rapamycin (mTOR) binding region yields immunophilin ligands, WYE-592 and ILS-920, with potent neurotrophic activities in cortical neuronal cultures, efficacy in a rodent model for ischemic stroke, and significantly reduced immunosuppressive activity. Surprisingly, both compounds showed higher binding selectivity for FKBP52 versus FKBP12, in contrast to previously reported immunophilin ligands. Affinity purification revealed two key binding proteins, the immunophilin FKBP52 and the β1-subunit of L-type voltage-dependent Ca 2+ channels (CACNB1). Electrophysiological analysis indicated that both compounds can inhibit L-type Ca 2+ channels in rat hippocampal neurons and F-11 dorsal root ganglia (DRG)/neuroblastoma cells. We propose that these immunophilin ligands can protect neurons from Ca 2+ -induced cell death by modulating Ca 2+ channels and promote neurite outgrowth via FKBP52 binding.
Databáze: OpenAIRE