title: Quercetin, not caffeine, is a major neuroprotective component in coffee.
abstract: Epidemiologic studies indicate that coffee consumption reduces the risk of Parkinson's disease and Alzheimer's disease. To determine the factors involved, we examined the protective effects of coffee components. The test involved prevention of neurotoxicity to SH-SY5Y cells that was induced by lipopolysaccharide plus interferon-γ or interferon-γ released from activated microglia and astrocytes. We found that quercetin, flavones, chlorogenic acid, and caffeine protected SH-SY5Y cells from these toxins. They also reduced the release of tumor necrosis factor-α and interleukin-6 from the activated microglia and astrocytes and attenuated the activation of proteins from P38 mitogen-activated protein kinase (MAPK) and nuclear factor kappa light chain enhancer of activated B cells (NFκB). After exposure to toxin containing glial-stimulated conditioned medium, we also found that quercetin reduced oxidative/nitrative damage to DNA, as well as to the lipids and proteins of SH-SY5Y cells. There was a resultant increase in [GSH]i in SH-SY5Y cells. The data indicate that quercetin is the major neuroprotective component in coffee against Parkinson's disease and Alzheimer's disease.
authors.affiliation: Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia Canada.
authors.forename: Moonhee
authors.initials: M
authors.lastname: Lee
authors.affiliation: Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia Canada.
authors.forename: Edith G
authors.initials: EG
authors.lastname: McGeer
authors.affiliation: Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia Canada. Electronic address: mcgeerpl@mail.ubc.ca.
authors.forename: Patrick L
authors.initials: PL
authors.lastname: McGeer
mesh_terms: D000544:Alzheimer Disease / Q000517:prevention & control*; D001253:Astrocytes / Q000378:metabolism; D002110:Caffeine / Q000302:isolation & purification / Q000494:pharmacology; D002478:Cells, Cultured; D002726:Chlorogenic Acid / Q000302:isolation & purification / Q000494:pharmacology; D003069:Coffee / Q000737:chemistry*; D004249:DNA Damage / Q000187:drug effects; D047309:Flavones / Q000302:isolation & purification / Q000494:pharmacology; D006801:Humans; D007371:Interferon-gamma / Q000633:toxicity; D015850:Interleukin-6 / Q000378:metabolism; D008070:Lipopolysaccharides / Q000633:toxicity; D017628:Microglia / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D018696:Neuroprotective Agents / Q000302:isolation & purification / Q000494:pharmacology*; D010300:Parkinson Disease / Q000517:prevention & control*; D008517:Phytotherapy; D011794:Quercetin / Q000302:isolation & purification / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D003069:Coffee; D047309:Flavones; C508600:IL6 protein, human; D015850:Interleukin-6; D008070:Lipopolysaccharides; D016328:NF-kappa B; D018696:Neuroprotective Agents; D014409:Tumor Necrosis Factor-alpha; D002726:Chlorogenic Acid; D002110:Caffeine; D007371:Interferon-gamma; D011794:Quercetin; D048051:p38 Mitogen-Activated Protein Kinases
keywords: Alzheimer disease; Astrocytes; IL-6; Microglia; Neurotoxicity; Parkinson disease; TNFα