Ra ostcobasts were isolated from the 21-day fetal rat calvchas. The cells were grown in DMEM Plus 10% FBS, and were treated for 24 h. with 10 μmol/L TPEN or 10 μmol/L TPEN supplemented with 10 μmol/L Zn2+. Apoptos...Ra ostcobasts were isolated from the 21-day fetal rat calvchas. The cells were grown in DMEM Plus 10% FBS, and were treated for 24 h. with 10 μmol/L TPEN or 10 μmol/L TPEN supplemented with 10 μmol/L Zn2+. Apoptosis of osteoblasts were measured by fiow cytometry, electron microscopy and DNA fragmentation analyzed by gel elecmphoresis. In addition, IP3 production and PKC activity were measmed in ordr to show whether they are involved in apoptosis in osteoblast induced by alnc deficiency. The results showed that 10 μmol/L TPEN could induce apoptosis in osteoblast in 24 h. But cells ed with 10μmol/L TPEN supplemented with 10 μmol/L Zn2+ showed no apoptotic changs in 24 h. TPEN significantly reduced the formation of IP3 and PKC activity after 24 h incubation. No differences were observed between the cells treated with TPEN supPlemented with Zn2+ simulaneosly and the untreated cells. It can be inferred that apoptosis induced by ainc deficiency may be due to the decreased activity of PKC which is impaired by reduced formation of IP3.展开更多
Objective To observe the effects of dexamethasone on proliferation, differentiation and apoptosis of adult human osteoblasts in vitro.Methods Iliac trabecular bone specimens were obtained from adult patients undergoin...Objective To observe the effects of dexamethasone on proliferation, differentiation and apoptosis of adult human osteoblasts in vitro.Methods Iliac trabecular bone specimens were obtained from adult patients undergoing necessary surgery. After the bone pieces were digested with collagenase-trypsin, osteoblasts were released and incubated at 37℃in a relative humidity of 95% and 5% CO2. Then, the cells were purified, and their passages were given DMEM-F12 and fetal bovine serum medium. Subsequently, 10^(-8) mol/L dexamethasone was added into the culture medium to incubate the osteoblasts for three days, and the cells from control groups were incubated without any drugs. All cells were observed continually with phase contrast microscope and transmission electron microscope. Finally, apoptosis was detected by the use of terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) and biochemical indices, alkaline phosphatase (ALP) and osteocalcin (OCN) were used to determine the effects of dexamethasone on proliferation, differentiation and apoptosis of adult osteoblasts in vitro.Results In the adult osteoblasts obtained by collagenase-trypsin digestion, it achieved high survial, stable biochemical indices and excellent purification. Under the condition of dexamethasone 10^(-8) mol/L and osteoblasts 10 000/ml, there was significant promotion of ALP and OCN secretion without cell apoptosis.Conclusions Dexamethasone has a significant effect on the proliferation and differentiation of adult osteoblasts in vitro without apoptosis, and dexamethasone at the suggested concentration can be used as positive control in drug studies for osteoporosis treatment.展开更多
文摘Ra ostcobasts were isolated from the 21-day fetal rat calvchas. The cells were grown in DMEM Plus 10% FBS, and were treated for 24 h. with 10 μmol/L TPEN or 10 μmol/L TPEN supplemented with 10 μmol/L Zn2+. Apoptosis of osteoblasts were measured by fiow cytometry, electron microscopy and DNA fragmentation analyzed by gel elecmphoresis. In addition, IP3 production and PKC activity were measmed in ordr to show whether they are involved in apoptosis in osteoblast induced by alnc deficiency. The results showed that 10 μmol/L TPEN could induce apoptosis in osteoblast in 24 h. But cells ed with 10μmol/L TPEN supplemented with 10 μmol/L Zn2+ showed no apoptotic changs in 24 h. TPEN significantly reduced the formation of IP3 and PKC activity after 24 h incubation. No differences were observed between the cells treated with TPEN supPlemented with Zn2+ simulaneosly and the untreated cells. It can be inferred that apoptosis induced by ainc deficiency may be due to the decreased activity of PKC which is impaired by reduced formation of IP3.
文摘Objective To observe the effects of dexamethasone on proliferation, differentiation and apoptosis of adult human osteoblasts in vitro.Methods Iliac trabecular bone specimens were obtained from adult patients undergoing necessary surgery. After the bone pieces were digested with collagenase-trypsin, osteoblasts were released and incubated at 37℃in a relative humidity of 95% and 5% CO2. Then, the cells were purified, and their passages were given DMEM-F12 and fetal bovine serum medium. Subsequently, 10^(-8) mol/L dexamethasone was added into the culture medium to incubate the osteoblasts for three days, and the cells from control groups were incubated without any drugs. All cells were observed continually with phase contrast microscope and transmission electron microscope. Finally, apoptosis was detected by the use of terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) and biochemical indices, alkaline phosphatase (ALP) and osteocalcin (OCN) were used to determine the effects of dexamethasone on proliferation, differentiation and apoptosis of adult osteoblasts in vitro.Results In the adult osteoblasts obtained by collagenase-trypsin digestion, it achieved high survial, stable biochemical indices and excellent purification. Under the condition of dexamethasone 10^(-8) mol/L and osteoblasts 10 000/ml, there was significant promotion of ALP and OCN secretion without cell apoptosis.Conclusions Dexamethasone has a significant effect on the proliferation and differentiation of adult osteoblasts in vitro without apoptosis, and dexamethasone at the suggested concentration can be used as positive control in drug studies for osteoporosis treatment.