title: Quercetin, a flavonoid, inhibits proliferation and increases osteogenic differentiation in human adipose stromal cells.
abstract: Flavonoids, which have been detected in a variety of foods, have been repeatedly reported to affect bone metabolism. However, the effects of flavonoids on osteoblastogenesis remain a matter of some controversy. In this study, the effects of quercetin on the differentiation and proliferation of human adipose tissue-derived stromal cells (hADSC) were determined. Quercetin was found to increase osteogenic differentiation in a dose-dependent manner. Other flavonoids, chrysin and kaempferol, were also shown to increase the osteogenic differentiation of hADSC, but this stimulatory effect was weaker than that associated with quercetin. Quercetin pretreatment administered prior to the induction of differentiation also exerted stimulatory effects on the osteogenic differentiation of hADSC. RT-PCR and real time PCR analysis showed that quercetin treatment induced an increase in the expression of osteopontin, BMP2, alkaline phosphatase and Runx2. Quercetin inhibited the proliferation of hADSC, but did not affect their survival. The pretreatment of quercetin increased ERK phosphorylation during osteogenic differentiation, although it did not increase ERK activity in control culture condition. ICI182780, an specific estrogen receptor antagonist, failed to inhibit the effects of quercetin on osteogenic differentiation. Quercetin-pretreated hADSC showed better bone regenerating ability in skull defect model of nude mice than naive cells. Our findings indicate that quercetin enhances osteogenic differentiation via an independent mechanism from estrogen receptor (ER) activation, and prove useful for in vivo bone engineering, using human mesencymal stem cells (hMSC).
authors.affiliation: Department of Physiology, College of Medicine, Pusan National University, Ami-Dong, Suh-Gu, Pusan, Republic of Korea.
authors.forename: Yeon Jeong
authors.initials: YJ
authors.lastname: Kim
authors.forename: Yong Chan
authors.initials: YC
authors.lastname: Bae
authors.forename: Kuen Taek
authors.initials: KT
authors.lastname: Suh
authors.forename: Jin Sup
authors.initials: JS
authors.lastname: Jung
mesh_terms: D017667:Adipocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism / Q000637:transplantation; D000818:Animals; D001861:Bone Regeneration / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D050659:Core Binding Factor Alpha 1 Subunit / Q000235:genetics; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D010012:Osteogenesis / Q000187:drug effects*; D053495:Osteopontin / Q000235:genetics; D011794:Quercetin / Q000494:pharmacology*; D012886:Skull / Q000293:injuries; D017154:Stromal Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism / Q000637:transplantation
chemical_list: D050659:Core Binding Factor Alpha 1 Subunit; C493709:RUNX2 protein, human; D053495:Osteopontin; D011794:Quercetin