title: Pulsed electromagnetic field may accelerate in vitro endochondral ossification.
abstract: Recapitulation of embryonic endochondral bone formation is a promising alternative approach to bone tissue engineering. However, the time-consuming process is one of the reasons the approach is unpractical. Here, we aimed at accelerating the in vitro endochondral ossification process of tissue engineering by using a pulsed electromagnetic field (PEMF). The rat bone marrow-derived stem cells were chondrogenic or hypertrophic differentiated in a three-dimensional pellet culture system, and treated with different intensities of PEMF (1, 2, and 5 mT with modulation frequency 750 Hz, carrier frequency 75 Hz and a duty ratio of 0.8, 3 h/day for 4 weeks). The effects of PEMF on hypertrophy and endochondral ossification were assessed by safranin O staining, immunohistochemistry, and quantitative real-time polymerase chain reaction. The results suggest that PEMF at 1, 2, and 5 mT may inhibit the maintenance of the cartilaginous phenotype and increase cartilage-specific extracellular matrix degradation in the late stage of chondrogenic differentiation. In addition, among the three different intensities, only PEMF at 1 mT directed the differentiation of chondrogenic-induced stem cell pellets to the hypertrophic stage and promoted osteogenic differentiation. Our findings provide the feasibility to optimize the process of in vitro endochondral ossification with PEMF stimulation.
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
authors.forename: Jue
authors.initials: J
authors.lastname: Wang
authors.forename: Na
authors.initials: N
authors.lastname: Tang
authors.forename: Qiang
authors.initials: Q
authors.lastname: Xiao
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Yu
authors.initials: Y
authors.lastname: Li
authors.forename: Juan
authors.initials: J
authors.lastname: Li
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
authors.forename: Zhihe
authors.initials: Z
authors.lastname: Zhao
authors.forename: Lijun
authors.initials: L
authors.lastname: Tan
mesh_terms: D000818:Animals; D001152:Arsenicals; D018929:Cell Culture Techniques; D049109:Cell Proliferation / Q000502:physiology; D002478:Cells, Cultured; D020219:Chondrogenesis / Q000502:physiology; D004574:Electromagnetic Fields; D006984:Hypertrophy / Q000503:physiopathology; D007150:Immunohistochemistry; D008297:Male; D059630:Mesenchymal Stem Cells / Q000502:physiology*; D010012:Osteogenesis / Q000502:physiology*; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction; D054457:Tissue Scaffolds; D059467:Transcriptome
chemical_list: D001152:Arsenicals; C548094:scorodite
keywords: bone marrow-derived stem cells; bone repair; cartilage; physical stimulation; tissue engineering