A series of experimental methods including MTT test,alkaline phosphatase(ALP) activity measurement,oil red O stain and measurement and mineralized function were employed to assess the effects of Y3+ on the proliferation,differentiation,adipogenic transdifferentiation and mineralization function of primary mouse osteoblasts(OBs) in vitro.The results indicated that Y3+(1×10-9,1×10-8,1×10-7,1×10-6,1×10-5,and 1×10-4 mol/L) promoted the proliferation of OBs on day 1,2 and 3.Y3+ had no effect on the differentiation of OBs at concentrations of 1×10-9 and 1×10-8 mol/L,promoted the differentiation of OBs at concentration of 1×10-7 mol/L,but turned to inhibit the differentiation of OBs at other tested concentrations on day 1.On day 2,Y3+ inhibited the differentiation of OBs at all tested concentrations.On day 3,Y3+ promoted the differentiation of OBs at lower concentrations of 1×10-9 and 1×10-8 mol/L,but turned to inhibit the differentiation of OBs at other concentrations.Y3+ promoted the adipocytic transdifferentiation of OBs at most tested concentrations on day 9 and 12.On day 15,Y3+ promoted the adipocytic transdifferentiation of OBs at lower concentrations of 1×10-9 and 1×10-8 mol/L,turned to inhibit at other tested concentrations.Y3+ inhibited the formation of mineralized matrix nodules of OBs at concentrations of 1×10-9,1×10-8 and 1×10-6 mol/L,but turned to promote the formation of mineralized matrix nodules of OBs at other tested concentrations.These findings suggested that the effects of Y3+ on the proliferation,differentiation,adipocytic transdifferentiation and mineralization function of primary OBs depended on the concentration and culture time,moreover,concentration and culture time were pivotal factors for switching the biological effects of Y3+ from toxicity to activity,from damage to protection,or from down-regulation to up-regulation.
A series of experimental methods including 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide (MTT) test,alkaline phosphatase (ALP) activity measurement,Oil Red O stain and measurement,mineralized function expression and quantitive real time RT-PCR (qRT-PCR) were employed to assess the effect of Nd3+ and Sm3+ on the proliferation,differentiation and mineralization function of primary osteoblasts (OBs) in vitro at cell and molecular levels.The experimental results suggest that concentration,culture time and ion species are pivotal factors for switching the biological effects of rare earth ions from toxicity to activity,from damage to protection,or from down-regulation to up-regulation.
ZHANG JinChaoSHANG MiQinZHANG DaWeiLI YaPingSUN JingCHEN Hang
The effects of cerium ion(Ce3+) on the proliferation,differentiation,adipocytic transdifferentiation and mineralization function of primary mouse osteoblasts(OBs) were investigated.The results indicated that Ce3+ at all concentrations(1×10-9,1×10-8,1×10-7,1×10-6,1×10-5,and 1×10-4 mol/L) promoted the proliferation of osteoblasts(OBs).On day 1 and 3,Ce3+ promoted the differentiation of OBs at concentrations of 1×10-9,1×10-7,and 1×10-6 mol/L,but inhibited the differentiation of OBs at higher concentrations.On day 2,Ce3+ inhibited the differentiation of OBs at tested concentrations.On day 9 and 12,Ce3+ inhibited the adipocytic transdifferentiation of OBs at most concentrations.On day 15,Ce3+ promoted the adipocytic transdifferentiation of OBs at concentrations of 1×10-9,1×10-6,1×10-5,and 1×10-4 mol/L,but had no effects at other concentrations.Ce3+ inhibited the formation of mineralized matrix nodules of OBs at concentrations of 1×10-9,1×10-8 and 1×10-7 mol/L,and promoted the formation of mineralized matrix nodules of OBs at other concentrations.These findings suggested that the effects of Ce3+ on the proliferation,differentiation,adipocytic transdifferentiation and mineralization function of primary OBs depended on the concentration and culture time;moreover,they were pivotal factors for switching the biological effects of Ce3+ from toxicity to activity,from damage to protection,or from down-regulation to up-regulation.
A series of experimental methods including 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide (MTT) test,alkaline phosphatase (ALP) activity measurement,oil red O stain and measurement,mineralized function and quantitive real time RT-PCR (qRT-PCR) were employed to assess the effects of Er3+ on the proliferation,differentiation and mineralization function of primary osteoblasts (OBs) in vitro at cell and molecular levels. The results indicated that Er3+ inhibited the proliferation of OBs at a concentration of 1×10-7 mol/L,but had no effect at other concentrations. Er3+ inhibited the differentiation of OBs at concentrations of 1×10-8,1×10-7,and 1×10-6 mol/L,but had no effect at a higher concentration of 1×10-5 mol/L. Er3+ had no effect on the transdifferentiation of OBs at tested concentrations. Er3+ inhibited the mineralization function of OBs at concentrations of 1×10-7,1×10-6,and 1×10-5 mol/L,but had no effect at a lower concentration of 1×10-8 mol/L. The expression of the mRNA for runt-related transcription factor 2 (RUNX-2) and peroxisome proliferators activated receptor γ (PPAR-γ) was down-regulated in the presence of 1×10-6 mol/L Er3+. These findings suggested that Er3+ might have negative effect on bone metabolism.
In order to elucidate the action of La3+ on bone metabolism,effects of La3+ on the osteogenic and adipogenic differentiation of pri-mary mouse bone marrow stromal cells(BMSCs) were studied by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT) test,alkaline phosphatase(ALP) activity measurement,mineralized function,oil red O stain and measurement.The results showed that La3+ pro-moted the proliferation of BMSCs except at 1×10-10 and 1×10-6 mol/L.The effect of La3+ on the osteogenic differentiation depended on con-centrations at the 7th day,but the osteogenic differentiation was inhibited at any concentration at the 14th day.La3+ promoted the formation of mineralized matrix nodules except at 1×10-8 and 1×10-5 mol/L.La3+ inhibited adipogenic differentiation except at 1×10-10 and 1×10-7 mol/L at the 10th day,and inhibited adipogenic differentiation except at 1×10-9 mol/L at the 16th day.These findings suggested that La3+ might have protective effect on bone at appropriate dose and time.This would be valuable for better understanding the mechanism of the effect of La3+ on bone metabolism.
