ABSTRACT
PURPOSE: In the present study, the effects of bFGF on the early responses of proliferation of UMR 106-01 osteoblast cells during cell cycle reentry from the latent(G0/G1) to the proliferative periods(S/M) were investigated. MATERIALS AND METHODS: The synchronized cell culture method using the serum starvation was utilized. After the addition of bFGF, the time courses of protein synthesis, DNA synthesis, thymidylate synthase(TS) activity, TS mRNA level and expression of c-fos were determined. RESULTS: 87% UMR 106-01 cells were synchronized to G0/G1 by serum starvation for seven days in the medium containing 0.1% serum. The protein level began to increase 3 hours after bFGF treatment and reached the maximum at 18 hours. TS activity began to increase 3 hours after the bFGF treatment and reached its peak at 6 hours while its mRNA level, determined by quantitative PCR, reached the maximum at 12 hours. The expression of c-fos protein, determined by western blot analysis and immunocytochemistry, increased 3 hours after bFGF treatment. On the contrary, these prominent changes and responses to bFGF were not observed in the case of using non-synchronized cells cultured in the medium containing 10% serum. CONCLUSION: Based on these data it can be concluded that bFGF-induced DNA synthesis in the early proliferative phase is due to increases in both TS activity and mRNA amount and that the increase in c-fos expression and TS activity occur before the increase in TS mRNA level.
Subject(s)
Blotting, Western , Cell Culture Techniques , Cell Cycle , DNA , Fibroblasts , Immunohistochemistry , Osteoblasts , Polymerase Chain Reaction , RNA, Messenger , Starvation , Thymidylate SynthaseABSTRACT
PURPOSE: In the present study, the effects of bFGF on the early responses of proliferation of UMR 106-01 osteoblast cells during cell cycle reentry from the latent(G0/G1) to the proliferative periods(S/M) were investigated. MATERIALS AND METHODS: The synchronized cell culture method using the serum starvation was utilized. After the addition of bFGF, the time courses of protein synthesis, DNA synthesis, thymidylate synthase(TS) activity, TS mRNA level and expression of c-fos were determined. RESULTS: 87% UMR 106-01 cells were synchronized to G0/G1 by serum starvation for seven days in the medium containing 0.1% serum. The protein level began to increase 3 hours after bFGF treatment and reached the maximum at 18 hours. TS activity began to increase 3 hours after the bFGF treatment and reached its peak at 6 hours while its mRNA level, determined by quantitative PCR, reached the maximum at 12 hours. The expression of c-fos protein, determined by western blot analysis and immunocytochemistry, increased 3 hours after bFGF treatment. On the contrary, these prominent changes and responses to bFGF were not observed in the case of using non-synchronized cells cultured in the medium containing 10% serum. CONCLUSION: Based on these data it can be concluded that bFGF-induced DNA synthesis in the early proliferative phase is due to increases in both TS activity and mRNA amount and that the increase in c-fos expression and TS activity occur before the increase in TS mRNA level.
Subject(s)
Blotting, Western , Cell Culture Techniques , Cell Cycle , DNA , Fibroblasts , Immunohistochemistry , Osteoblasts , Polymerase Chain Reaction , RNA, Messenger , Starvation , Thymidylate SynthaseABSTRACT
The knowledge of gene regulation of serotonin transporter mRNA may provide clues to understanding how antidepressants affect their therapeutic actions. Recently, the effects of antidepressants on the serotonin transporter have been investigated but yielded controversial results. To study this further, we performed in situ hybridization for serotonin transporter mRNA in rats(treatment group, n=5)receiving long term(14 days)treatment with a selective serotonin reuptake inhibiting antidepressant, sertraline(10mg/kg, i.p) Following sertraline treatment, a significant(p<0.05)ncrease in hybridization of serotonin transporter mRNA was observed compared to that observed in vehicle-treated rats(control group, n=5) This result may be interpreted as a compensatory mechanism to reduce synaptic levels of serotonin which were increased by long term sertraline treatment.
Subject(s)
Animals , Rats , Antidepressive Agents , Brain , In Situ Hybridization , RNA, Messenger , Serotonin Plasma Membrane Transport Proteins , Serotonin , SertralineABSTRACT
BACKGROUND: The expression of adhesion molecules contribute to development of systemic diseases. Vascular cell adhesion molecule-l(VCAM-1) is an endothelial cell membrane glycoprotein that has been implicated in leukocyte/endothelial cell interactions in inflammation. OBJECTIVE: The aim of this study was to characterize the surface expression and regulation of VCAM-1 on two different endothelial cells. METHOD: We examined the effects of the expression of VCAM-1 in two different endothelial cells, isolated from human umbilical cords and human glomerulus. Expression of VCAM-1 was measured by enzyme-linked immunosorbent assay(ELISA) and flow cytometry. RESULTS: In human umbilical cord endothelial cells(HUVECs), both interleukin-l B(IL-lB) and tumor necrosis factor-a (TNF-a) increased VCAM-1 expression. VCAM-1 expression increased by TNF-a was higher than that increased by IL-lB. In human glomerular endothelial cells(HGECs), IL-lB and TNF-a markedly increased VCAM-1 expression. Conclusion. The regulation of VCAM-1 appears to be somewhat different in HGECs compared with HUVECs. These differences between the responsiveness of the two cells may possibly indicate inherent differences in endothelial cell derived from different vascular beds.
Subject(s)
Humans , Cell Adhesion , Cell Communication , Cytokines , Endothelial Cells , Flow Cytometry , Inflammation , Membrane Glycoproteins , Necrosis , Umbilical Cord , Vascular Cell Adhesion Molecule-1ABSTRACT
In vivo 31P NMR spectra were obtained in eight infant brain at 4.7T. Each phosphorus metabolite and its ratio were analyzed to evaluate the brain damage and maturity, and compared with the reported data obtained at the lower field strength. Measurement of T1 relaxation time at 4.7T was done in an infant and a cat brain in vivo. PCr/Pi and PCr/β-ATP ratio were used as a marker of brain damage. PME/PDE revealed higher values than those of the reported data obtained at the lower field strength and the difference was partly attributed to the long T1 relaxation time of PME rather than the brain immaturity. Although the resolution of the spectrum was improved at 4.7T, a long repetition time is recommended to minimize T1difference of phosphorus metabolites of brain at 4.7T.