curcumin and Bulbo-Spinal-Atrophy--X-Linked

Spinal and bulbar muscular atrophy (SBMA, also known as Kennedy's disease) is one of nine neurodegenerative disorders that are caused by expansion of polyglutamine-encoding CAG repeats. Intracellular accumulation of abnormal proteins in these diseases, a pathological hallmark, is associated with defects in protein homeostasis. Enhancement of the cellular proteostasis capacity with small molecules has therefore emerged as a promising approach to treatment. Here, we characterize a novel curcumin analog, ASC-JM17, as an activator of central pathways controlling protein folding, degradation and oxidative stress resistance. ASC-JM17 acts on Nrf1, Nrf2 and Hsf1 to increase the expression of proteasome subunits, antioxidant enzymes and molecular chaperones. We show that ASC-JM17 ameliorates toxicity of the mutant androgen receptor (AR) responsible for SBMA in cell, fly and mouse models. Knockdown of the Drosophila Nrf1 and Nrf2 ortholog cap 'n' collar isoform-C, but not Hsf1, blocks the protective effect of ASC-JM17 on mutant AR-induced eye degeneration in flies. Our observations indicate that activation of the Nrf1/Nrf2 pathway is a viable option for pharmacological intervention in SBMA and potentially other polyglutamine diseases.

Topics: Animals; Bulbo-Spinal Atrophy, X-Linked; Curcumin; Disease Models, Animal; DNA-Binding Proteins; Drosophila melanogaster; Drosophila Proteins; Gene Knockdown Techniques; Heat Shock Transcription Factors; Humans; Mice; Muscular Disorders, Atrophic; NF-E2-Related Factor 1; NF-E2-Related Factor 2; Oxidative Stress; Peptides; Proteasome Endopeptidase Complex; Protein Aggregation, Pathological; Protein Folding; Receptors, Androgen; Signal Transduction; Small Molecule Libraries; Transcription Factors; Trinucleotide Repeat Expansion