The flavonoid fisetin promotes nerve cell survival from trophic factor withdrawal by enhancement of proteasome activity.
To explore the possibility that specific flavonoids can substitute for neurotrophic factors, we examined the ability of the flavonol fisetin and several related flavonoids to support the survival of low density, serum-free cultures of rat cortical neurons. Normally these cells die within 24h in the absence of trophic factors but in the presence of fisetin and several related flavonoids the cells survive and produce long neurites. While the survival-promoting effect of several of the fisetin-related flavonoids was partially dependent on ERK activation, the effect of fisetin was not. Fisetin can enhance glutathione synthesis but the survival-promoting effect of fisetin was also not dependent on glutathione. However, proteasome inhibitors almost completely blocked the ability of fisetin to promote survival. Consistent with this observation, fisetin increased proteasome activity. Together these results demonstrate a new activity for fisetin and tie this activity to its neurotrophic effects.
Maher
Pamela
P
The Salk Institute for Biological Studies, Cellular Neurobiology, 10010 N. Torrey Pines Road, La Jolla, CA 92037, USA. pmaher@salk.edu
D000818:Animals; D018929:Cell Culture Techniques; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology; D016895:Culture Media, Serum-Free; D004305:Dose-Response Relationship, Drug; D004622:Embryo, Mammalian / Q000166:cytology; D005419:Flavonoids / Q000494:pharmacology*; D044948:Flavonols; D009414:Nerve Growth Factors / Q000494:pharmacology*; D009474:Neurons / Q000187:drug effects*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D051381:Rats; D013997:Time Factors
D016895:Culture Media, Serum-Free; D005419:Flavonoids; D044948:Flavonols; D009414:Nerve Growth Factors; D046988:Proteasome Endopeptidase Complex; C017875:fisetin