The Effects of Direct Electrical Stimulation on Gene Regulation and Differentiation of Human Dental Pulp Stem Cells During Osteogenesis Process

• Main Authors: Hong-wei Guo, 郭弘偉
• Other Authors: Wei-wen Hu
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/uwzwm4

碩士 === 國立中央大學 === 化學工程與材料工程學系 === 103 === Substrate-mediated direct current (DC) was studied the effects of electrical stimulation (ES) on human dental pulp stem cells (hDPSC) during osteogenic process. Conductive polypyrrole (PPy) films were prepared as substrate for cell seeding. Osteogenic medium was applied to trigger cell differentiation, and a constant electric field (2 V/6 cm) was applied for 4 h once medium was supplied osteogenic contents. At Day 14, the mineralization of hDPSCs treated with DC stimulation were highly improved that its calcium deposition was 2 to 3 times more than the untreated group. The transcriptions of osteo-differentiation relative genes were examined using quantitative real-time polymerase chain reaction (qPCR) at different days. The DC treatment was capable of immediately leading the enhancement of the transcriptions of BMPs, VEGF, Runx-2, and Osx, by which ALP, Col-1, and BGLAP were thus up-regulated with time. Although the levels of SMAD-1/5 were not affected, the Western blot results indicated that the phosphorylations of SMAD-1/5 were highly improved. It suggested the ES likely activated SMAD signal pathway to upregulate Runx-2 then improved osteogenesis. Finally, hDPSCs at different stages of osteo-differentiation were individually treated ES. The mineralization results revealed that osteogenesis were enhanced when hDPSCs were treated ES at early stages of osteo-differentiation, especially at Day 4. In contrast, there were almost no differences of mineralizations between the ES treatments at late stages and the untreated group. The improvement was extremely obvious for the calcium deposition at Day 12. However, the saturated calcium deposition of ES treated and untreated groups at Day 21 were almost the same. These results suggested that ES treatment likely accelerated osteo-differentiation.