title: Europium-Doped Gd2O3Nanotubes Increase Bone Mineral Density in Vivo and Promote Mineralization in Vitro.
abstract: Europium-doped Gd2O3nanotubes (Gd2O3:Eu3+NTs) have been extensively applied in the field of bioscience for their photostability and magnetic properties. Nevertheless, the distribution and interaction between Gd2O3:Eu3+NTs and metabolism of bone are not yet sufficiently understood. In this study, a systematic study of the toxicity and distribution of Gd2O3:Eu3+NTs in mice after oral administration was carried out. The results showed that a small number of the Gd2O3:Eu3+NTs could pass through biological barriers into the lung, liver, and spleen, but a high concentration was observed in bone. Furthermore, the effects of Gd2O3:Eu3+NTs on bone metabolism were systematically studied in vitro and in vivo when accumulating in bone. After being administered to mice, the Gd2O3:Eu3+NTs extremely enhanced the bone mineral density and bone biomechanics. In vitro the Gd2O3:Eu3+NTs increased the alkaline phosphatase (ALP) activity and mineralization and promoted the expression of osteogenesis genes in preosteoblasts MC3T3-E1 through activation of the BMP signaling pathway. This study will be significant for appropriate application of Gd2O3:Eu3+NTs in the biomedical field and expounding the molecular mechanism of bone metabolism.
authors.forename: Huifang
authors.initials: H
authors.lastname: Liu
authors.affiliation: College of Basic Medical Science, Hebei University , Baoding 071000, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Jin
authors.affiliation: Affiliated Hospital of Hebei University , Baoding 071000, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Ge
authors.forename: Guang
authors.initials: G
authors.lastname: Jia
authors.forename: Zhenhua
authors.initials: Z
authors.lastname: Li
authors.forename: Xinjian
authors.initials: X
authors.lastname: Yang
authors.forename: Shizhu
authors.initials: S
authors.lastname: Chen
authors.forename: Min
authors.initials: M
authors.lastname: Ge
authors.forename: Wentong
authors.initials: W
authors.lastname: Sun
authors.forename: Dandan
authors.initials: D
authors.lastname: Liu
authors.forename: Jinchao
authors.identifier: http://orcid.org/0000-0002-5279-0468
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000818:Animals; D015519:Bone Density; D005063:Europium; D005682:Gadolinium; D051379:Mice; D043942:Nanotubes; D010006:Osteoblasts; D010012:Osteogenesis; D015398:Signal Transduction
chemical_list: D005063:Europium; C030581:gadolinium oxide; D005682:Gadolinium
keywords: BMP signaling pathway; bone mineral density; europium-doped Gd2O3 nanotube; mineralization; phosphorylated-Smad1/5