title: Aluminum trichloride inhibits osteoblast mineralization via TGF-β1/Smad signaling pathway.
abstract: Osteoporosis is a major global public health problem. Aluminum (Al) exposure inhibits osteoblast mineralization and induces osteoporosis. However, the exact mechanism is not fully understood. The transforming growth factor β1 (TGF-β1)/Smad pathway is a major signaling cascade in regulating osteoblast mineralization. To investigate whether TGF-β1/Smad signaling pathway was involved in the Al-induced inhibition of osteoblast mineralization, osteoblasts were cultured and exposed to different concentrations of aluminum trichloride (AlCl3) (containing 0, 0.01, 0.02 and 0.04 mg/mL Al(3+)) for 24 h. We found that mineralized matrix nodules, mRNA expressions of alkaline phosphatase (ALP), type I collagen (Col I), TGF-β1, TGF-β type I receptor, TGF-β type II receptor and Smad4, protein expressions of TGF-β1 and p-Smad2/3, Smad2/3/4 trimeric complex were all decreased, whereas the mRNA expressions of Smad7 were increased in the AlCl3-treated groups compared with those in control. In conclusion, these results indicated that AlCl3 inhibited osteoblast mineralization via TGF-β1/Smad signaling pathway in rat osteoblasts. Our findings could provide novel insights into the mechanisms of action of AlCl3 in osteoporosis.
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China.
authors.forename: Xudong
authors.initials: X
authors.lastname: Sun
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Cao
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China.
authors.forename: Qiuyue
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China.
authors.forename: Miao
authors.initials: M
authors.lastname: Li
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China.
authors.forename: Lulu
authors.initials: L
authors.lastname: Han
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China. Electronic address: liyanfei@neau.edu.cn.
authors.forename: Yanfei
authors.initials: Y
authors.lastname: Li
mesh_terms: D000077410:Aluminum Chloride; D017607:Aluminum Compounds / Q000494:pharmacology*; D000818:Animals; D002478:Cells, Cultured; D002712:Chlorides / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D010006:Osteoblasts / Q000187:drug effects* / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects*; D051785:Smad Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D013329:Structure-Activity Relationship; D053773:Transforming Growth Factor beta1 / Q000378:metabolism*
chemical_list: D017607:Aluminum Compounds; D002712:Chlorides; D051785:Smad Proteins; D053773:Transforming Growth Factor beta1; D000077410:Aluminum Chloride
keywords: Aluminum trichloride; Mineralization; Osteoblasts; Rat; TGF-β1/Smad signaling pathway