Browsing by Author "Hsieh, Dean-Kuo"

Now showing 1 - 2 of 2

Effect of Pulsed Electromagnetic Field on the Proliferation and Differentiation Potential of Human Bone Marrow Mesenchymal Stem Cells
(2009-05-01)
Sun, Li-Yi
;
Hsieh, Dean-Kuo
;
Yu, Tzai-Chiu
;
Chiu, Hsien-Tai
;
Lu, Sheng-Fen
Pulsed electromagnetic fields (PEMFs) have been used clinically to slow down osteoporosis and accelerate the healing of bone fractures for many years. The aim of this study is to investigate the effect of PEMFs on the proliferation and differentiation potential of human bone marrow mesenchymal stem cells (BMMSC). PEMF stimulus was administered to BMMSCs for 8 h per day during culture period. The PEMF applied consisted of 4.5 ms bursts repeating at 15 Hz, and each burst contained 20 Pulses. Results showed that about 59% and 40% more viable BMMSC cells were obtained in the 2 PEMF-exposed Cultures at 24 h after plating for the seeding density of 1000 and 3000 cells/cm(2) respectively. Although, based on the kinetic analysis, the growth rates of BMMSC during the exponential growth phase were not significantly affected, 20-60% higher cell densities were achieved during the exponentially expanding stage. Many newly divided cells appeared from 12 to 16 h after the PEMF treatment as revealed by the cell cycle analysis. These results Suggest that PEMF exposure Could enhance the BMMSC cell proliferation during the exponential phase and it possibly resulted from the shortening of the lag phase. In addition, according to the cytochemical and immunofluorescence analysis performed, the PEMF-exposed BMMSC showed multi-lineage differentiation potential similar to the control group. Bioelectromagnetics 30:251-260, 2009. (C) 2009 Wiley-Liss. Inc.
Pulsed Electromagnetic Fields Accelerate Proliferation and Osteogenic Gene Expression in Human Bone Marrow Mesenchymal Stem Cells During Osteogenic Differentiation
(2010-04-01)
Sun, Li-Yi
;
Hsieh, Dean-Kuo
;
Lin, Po-Cheng
;
Chiu, Hsien-Tai
;
Chiou, Tzyy-Wen
Osteogenesis is a complex series of events involving the differentiation of mesenchymal stem cells to generate new bone. In this study, we examined the effect of pulsed electromagnetic fields (PEMFs) on cell proliferation, alkaline phosphatase (ALP) activity, mineralization of the extracellular matrix, and gene expression in bone marrow mesenchymal stem cells (BMMSCs) during osteogenic differentiation. Exposure of BMMISCs to PEMFs increased cell proliferation by 29.6% compared to untreated cells at day 1 of differentiation. Semi-quantitative RT-PCR indicated that PEMFs significantly altered temporal expression of osteogenesis-related genes, including a 2.7-fold increase in expression of the key osteogenesis regulatory gene cbfa1, compared to untreated controls. In addition, exposure to PEMFs significantly increased ALP expression during the early stages of osteogenesis and substantially enhanced mineralization near the midpoint of osteogenesis. These results suggest that PEMFs enhance early cell proliferation in B M MSC-mediated osteogenesis, and accelerate the osteogenesis. Bioelectromatmetics 31:209-219, 2010. (C) 2009 Wiley-Liss, Inc.