title: Bioactive effects of quercetin in the central nervous system: Focusing on the mechanisms of actions.
abstract: Quercetin, a ubiquitous flavonoid that is widely distributed in plants is classified as a cognitive enhancer in traditional and oriental medicine. The protective effects of quercetin for the treatment of neurodegenerative disorders and cerebrovascular diseases have been demonstrated in both in vitro and in vivo studies. The free radical scavenging activity of quercetin has been well-documented, wherein quercetin has been observed to exhibit protective effects against oxidative stress mediated neuronal damage by modulating the expression of NRF-2 dependent antioxidant responsive elements, and attenuation of neuroinflammation by suppressing NF-κB signal transducer and activator of transcription-1 (STAT-1). Several in vitro and in vivo studies have also shown that quercetin destabilizes and enhances the clearance of abnormal protein such as beta- amyloid peptide and hyperphosphorlyated tau, the key pathological hallmarks of Alzheimer's disease. Quercetin enhances neurogenesis and neuronal longevity by modulating a broad number of kinase signaling cascades such as phophoinositide 3- kinase (P13-kinase), AKT/PKB tyrosine kinase and Protein kinase C (PKC). Quercetin has also been well reported for its ability to reverse cognitive impairment and memory enhancement during aging. The current review focuses on summarizing the recent findings on the neuroprotective effect of quercetin, its mechanism of action and its possible roles in the prevention of neurological disorders.
authors.affiliation: Department of Nanoscience and Technology, Alagappa University (Science Campus), Karaikudi 630 004, Tamil Nadu, India.
authors.forename: Natarajan
authors.initials: N
authors.lastname: Suganthy
authors.affiliation: Department of Biotechnology, Alagappa University (Science Campus), Karaikudi 630 004, Tamil Nadu, India. Electronic address: devikasi@yahoo.com.
authors.forename: Kasi Pandima
authors.initials: KP
authors.lastname: Devi
authors.affiliation: Applied Biotechnology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Seyed Fazel
authors.initials: SF
authors.lastname: Nabavi
authors.affiliation: Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Australia.
authors.forename: Nady
authors.initials: N
authors.lastname: Braidy
authors.affiliation: Applied Biotechnology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran. Electronic address: Nabavi208@gmail.com.
authors.forename: Seyed Mohammad
authors.initials: SM
authors.lastname: Nabavi
mesh_terms: D000818:Animals; D001682:Biological Availability; D002490:Central Nervous System / Q000187:drug effects*; D006801:Humans; D008954:Models, Biological; D018696:Neuroprotective Agents / Q000494:pharmacology; D011794:Quercetin / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D018696:Neuroprotective Agents; D011794:Quercetin
keywords: Autophagy; Glutamate excitotoxicity; Neurogenesis; Neuroinflammation; Oxidative stress; Quercetin