title: Cognitive-enhancing effects of Rhus verniciflua bark extract and its active flavonoids with neuroprotective and anti-inflammatory activities.
abstract: The neuroprotective potential of flavonoids within the brain comprises anti-apoptosis of neuronal cells, anti-neuroinflammation and enhancement of cognitive function. We reported that Rhus vernciflua inhibits glutamate-induced neurotoxicity in primary cultured rat cortical cells. Here we narrowed it down to get neuroprotective fractions from the plant yielding flavonoid-rich ethyl acetate fraction (PREF). Among its active flavonoids, fisetin exhibited not only inhibitory effect against lipopolysaccharide (LPS)-induced neuroinflammation by suppressing inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 but also memory enhancing effects via reactivation of cAMP responsive element binding protein (CREB)-brain derived neurotrophic factor (BDNF) pathway in memory-impaired mice by scopolamine. Butein also showed a similar activity to fisetin even though to a lesser extent. The neuroprotection by PREF and selected flavonoids may involve maintenance of antioxidant defense mechanism including glutathione peroxidase (GSH-Px), glutathione reductase (GR) and superoxide dismutase (SOD). Conclusively, we demonstrate the R. vernciflua bark extract and its active flavonoids with potent neuroprotective and anti-inflammatory effects might be good therapeutic candidates as cognitive-enhancers.
authors.affiliation: College of Pharmacy and Research Institute of Pharmaceutical Science, Seoul National University, Seoul 151-742, Republic of Korea.
authors.forename: Namki
authors.initials: N
authors.lastname: Cho
authors.forename: Ki Yong
authors.initials: KY
authors.lastname: Lee
authors.forename: Jungmoo
authors.initials: J
authors.lastname: Huh
authors.forename: Ji Hoon
authors.initials: JH
authors.lastname: Choi
authors.forename: Heejung
authors.initials: H
authors.lastname: Yang
authors.forename: Eun Ju
authors.initials: EJ
authors.lastname: Jeong
authors.forename: Hong Pyo
authors.initials: HP
authors.lastname: Kim
authors.forename: Sang Hyun
authors.initials: SH
authors.lastname: Sung
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D003071:Cognition / Q000187:drug effects*; D005419:Flavonoids / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009419:Nerve Tissue Proteins / Q000378:metabolism; D018696:Neuroprotective Agents / Q000494:pharmacology*; D018384:Oxidative Stress / Q000187:drug effects; D024301:Plant Bark / Q000737:chemistry; D010936:Plant Extracts / Q000494:pharmacology*; D029045:Rhus / Q000737:chemistry*; D012601:Scopolamine / Q000494:pharmacology
chemical_list: D000893:Anti-Inflammatory Agents; D000975:Antioxidants; D005419:Flavonoids; D009419:Nerve Tissue Proteins; D018696:Neuroprotective Agents; D010936:Plant Extracts; D012601:Scopolamine
keywords: Anti-neuroinflammation; CREB–BDNF signaling; Cognitive-enhancing activity; Flavonoids; Rhus verniciflua bark