title: The stimulation of osteogenic differentiation of human adipose-derived stem cells by ionic products from akermanite dissolution via activation of the ERK pathway.
abstract: Our previous study indicates that akermanite, a type of Ca-, Mg-, Si-containing bioceramic, can promote the osteogenic differentiation of hASCs. To elucidate the underlying mechanism, we investigated the effect of the extract from akermanite, on proliferation and osteogenic differentiation of hASCs. The original extract was obtained at 200 mg akermanite/ml LG-DMEM and further diluted with LG-DMEM. The final extracts were denoted as 1/2, 1/4, 1/8, 1/16, and 1/32 extracts based on the concentrations of the original extract. The LDH assay and live/dead stain were used to reveal the cytotoxicity of the different extracts on hASCs, while the DNA assay was carried out to quantitatively evaluate the proliferation of cells after being cultured with the extracts for 1, 3 and 7 days. Flow cytometry for cell cycle analysis was carried out on cells cultured in two media (GM and 1/2 extract) in order to further analyze the effect of the extract on cell proliferation behaviors. Osteogenic differentiation of hASCs cultured in the extracts was detected by ALP expression and calcium deposition, and further confirmed by real-time PCR analysis. It was shown that Ca, Mg and Si ions in the extract could suppress the LDH release and proliferation of hASCs, whereas promote their osteogenic differentiation. Such effects were concentration-dependent with the 1/4 extract (Ca 2.36 mM, Mg 1.11 mM, Si 1.03 mM) being the optimum in promoting the osteogenic differentiation of hASCs. An immediate increase in ERK was observed in cells cultured in the 1/4 extract and such osteogenic differentiation of hASCs promoted by released ions could be blocked by MEK1-specific inhibitor, PD98059. Briefly, Ca, Mg and Si ions extracted from akermanite in the concentrations of 2.36, 1.11, 1.03 mM, respectively, could facilitate the osteogenic differentiation of hASCs via an ERK pathway, and suppress the proliferation of hASCs without significant cytotoxicity.
authors.affiliation: Department of Plastic and Reconstructive Surgery, Shanghai 9th People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China.
authors.forename: Huijie
authors.initials: H
authors.lastname: Gu
authors.forename: Fangfang
authors.initials: F
authors.lastname: Guo
authors.forename: Xiao
authors.initials: X
authors.lastname: Zhou
authors.forename: Lunli
authors.initials: L
authors.lastname: Gong
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhang
authors.forename: Wanyin
authors.initials: W
authors.lastname: Zhai
authors.forename: Lei
authors.initials: L
authors.lastname: Chen
authors.forename: Lian
authors.initials: L
authors.lastname: Cen
authors.forename: Shuo
authors.initials: S
authors.lastname: Yin
authors.forename: Jiang
authors.initials: J
authors.lastname: Chang
authors.forename: Lei
authors.initials: L
authors.lastname: Cui
mesh_terms: D000273:Adipose Tissue / Q000166:cytology*; D000328:Adult; D001672:Biocompatible Materials / Q000737:chemistry / Q000378:metabolism; D001826:Body Fluids / Q000737:chemistry; D002118:Calcium / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects; D002516:Ceramics / Q000737:chemistry / Q000378:metabolism*; D004789:Enzyme Activation; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D005419:Flavonoids / Q000494:pharmacology; D006801:Humans; D007477:Ions / Q000494:pharmacology*; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000502:physiology; D008274:Magnesium / Q000494:pharmacology; D008422:Materials Testing; D015675:Osteocalcin / Q000378:metabolism; D010012:Osteogenesis / Q000187:drug effects* / Q000502:physiology; D012825:Silicon / Q000494:pharmacology; D013234:Stem Cells / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*
chemical_list: D001672:Biocompatible Materials; D005419:Flavonoids; D007477:Ions; D015675:Osteocalcin; C023506:Glass ceramics; D048049:Extracellular Signal-Regulated MAP Kinases; D008274:Magnesium; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one; D002118:Calcium; D012825:Silicon