title: Boron Accelerates Cultured Osteoblastic Cell Activity through Calcium Flux.
abstract: A low concentration of boron (B) accelerates the proliferation and differentiation of mammalian osteoblasts. The aim of this study was to investigate the effects of 0.1 mM of B on the membrane function of osteoblastic cells in vitro. Genes involved in cell activity were investigated using gene expression microarray analyses. The Ca2+influx and efflux were evaluated to demonstrate the activation of L-type Ca2+channel for the Ca2+influx, and that of Na+/K+-ATPase for the Ca2+efflux. A real-time PCR analysis revealed that the messenger RNA (mRNA) expression of four mineralization-related genes was clearly increased after 3 days of culture with a B-supplemented culture medium. Using microarray analyses, five genes involved in cell proliferation and differentiation were upregulated compared to the control group. Regarding the Ca2+influx, in the nifedipine-pretreated group, the relative fluorescence intensity for 1 min after adding B solution did not increase compared with that for 1 min before addition. In the control group, the relative fluorescence intensity was significantly increased compared with the experimental group (P < 0.05). Regarding the Ca2+efflux, in the experimental group cultured in 0.1 mM of B-supplemented medium, the relative fluorescence intensity for 10 min after ouabain treatment revealed a significantly lower slope value compared with the control group (P < 0.01). This is the first study to demonstrate the acceleration of Ca2+flux by B supplementation in osteoblastic cells. Cell membrane stability is related to the mechanism by which a very low concentration of B promotes the proliferation and differentiation of mammalian osteoblastic cells in vitro.
authors.affiliation: Department of Cariology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8588, Japan.
authors.forename: Mark Luigi Fabian
authors.initials: ML
authors.lastname: Capati
authors.affiliation: Department of Cariology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8588, Japan.
authors.forename: Ayako
authors.initials: A
authors.lastname: Nakazono
authors.affiliation: Department of Cariology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8588, Japan.
authors.forename: Kazunari
authors.initials: K
authors.lastname: Igawa
authors.affiliation: Department of Cariology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8588, Japan.
authors.forename: Kensuke
authors.initials: K
authors.lastname: Ookubo
authors.affiliation: Department of Cariology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8588, Japan.
authors.forename: Yuya
authors.initials: Y
authors.lastname: Yamamoto
authors.affiliation: Department of Cariology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8588, Japan.
authors.forename: Kajirou
authors.initials: K
authors.lastname: Yanagiguchi
authors.affiliation: Department of Cariology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8588, Japan.
authors.forename: Shisei
authors.initials: S
authors.lastname: Kubo
authors.affiliation: Department of Cariology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8588, Japan.
authors.forename: Shizuka
authors.initials: S
authors.lastname: Yamada
authors.affiliation: Department of Cariology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8588, Japan. hayashi@nagasaki-u.ac.jp.
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Hayashi
mesh_terms: D001895:Boron / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D020746:Calcium Channels, L-Type / Q000096:biosynthesis; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis; D010006:Osteoblasts / Q000378:metabolism*; D000254:Sodium-Potassium-Exchanging ATPase / Q000096:biosynthesis
chemical_list: D020746:Calcium Channels, L-Type; D000254:Sodium-Potassium-Exchanging ATPase; D001895:Boron; D002118:Calcium
keywords: Boron; Ca2+ flux; Cell proliferetion; Differentiation; Odontoblast