title: Quercetin protects human brain microvascular endothelial cells from fibrillar β-amyloid1-40-induced toxicity.
abstract: Amyloid beta-peptides (Aβ) are known to undergo active transport across the blood-brain barrier, and cerebral amyloid angiopathy has been shown to be a prominent feature in the majority of Alzheimer׳s disease. Quercetin is a natural flavonoid molecule and has been demonstrated to have potent neuroprotective effects, but its protective effect on endothelial cells under Aβ-damaged condition is unclear. In the present study, the protective effects of quercetin on brain microvascular endothelial cells injured by fibrillar Aβ 1-40 (fAβ 1-40) were observed. The results show that fAβ 1-40-induced cytotoxicity in human brain microvascular endothelial cells (hBMECs) can be relieved by quercetin treatment. Quercetin increases cell viability, reduces the release of lactate dehydrogenase, and relieves nuclear condensation. Quercetin also alleviates intracellular reactive oxygen species generation and increases superoxide dismutase activity. Moreover, it strengthens the barrier integrity through the preservation of the transendothelial electrical resistance value, the relief of aggravated permeability, and the increase of characteristic enzyme levels after being exposed to fAβ 1-40. In conclusion, quercetin protects hBMECs from fAβ 1-40-induced toxicity.
authors.affiliation: Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
authors.forename: Yongjie
authors.initials: Y
authors.lastname: Li
authors.affiliation: Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
authors.forename: Sibai
authors.initials: S
authors.lastname: Zhou
authors.affiliation: Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
authors.forename: Jinze
authors.initials: J
authors.lastname: Li
authors.affiliation: Xinjiang Key Laboratory of Xinjiang Uygur Medicine, Xinjiang Institute of Materia Medica, Urumqi 830004, China.
authors.forename: Yuhua
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Xinjiang Key Laboratory of Xinjiang Uygur Medicine, Xinjiang Institute of Materia Medica, Urumqi 830004, China.
authors.forename: Hamlati
authors.initials: H
authors.lastname: Hasimu
authors.affiliation: Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China ; Xinjiang Key Laboratory of Xinjiang Uygur Medicine, Xinjiang Institute of Materia Medica, Urumqi 830004, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Liu
authors.affiliation: Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
authors.forename: Tiantai
authors.initials: T
authors.lastname: Zhang
keywords: Alzheimer׳s disease; Fibrillar Aβ1–40; Human brain microvascular  endothelial cells; Quercetin