脉冲超声及电磁场对大鼠骨髓间充质干细胞体外成软骨分化过程中细胞外基质溢出的影响

Effects of pulsed ultrasound and pulsed electromagnetic field on the extracellular matrix secretion of rat bone marrow mesenchymal stem cell pellets in chondrogenesis

目的研究脉冲超声以及脉冲电磁场对大鼠骨髓间充质干细胞微球体外成软骨分化中细胞外基质向培养基中溢出的影响。方法将干细胞微球在成软骨培养基中进行培养,分为无刺激组(N组)、脉冲超声(100、150、200 mW·cm^(-2))刺激组和脉冲电磁场(1、2、5 mT)刺激组。2周后采用酶联免疫吸附测定法检测培养液中Ⅱ型胶原和糖胺聚糖的质量浓度。结果脉冲超声刺激组细胞外基质分泌较N组增多(P<0.05),但3个刺激组间的差异无统计学意义(P>0.05);脉冲电磁场组对Ⅱ型胶原分泌无明显影响(P>0.05),1 mT组对糖胺聚糖的分泌无明显影响(P>0.05),2 mT和5 mT组糖胺聚糖的分泌减少(P<0.05)。结论在促进干细胞成软骨分化的过程中,特定参数的脉冲电磁场可能起到防止增多的细胞外基质向组织外扩散溢出的作用。

Objective To study the effects of pulsed ultrasound（PUS） and pulsed electromagnetic fields（PEMF） on the secretion of extracellular matrix from a culture complex during in vitro chondrogenesis. Methods All the rat bone marrow mesenchymal stem cell pellets were cultured in achondrogenic medium. Different intensities of PUS（100, 150, and 200 mW·cm^（-2）） and PEMF（1, 2, and 5 mT） were applied to the cell pellets for 2 weeks. Group N was cultured without PUS and PEMF stimulation as control. The culture medium was collected after 2 weeks of culture. Enzyme-linked immunosorbent assay（ELISA） was used to detect the type of collagen and glycosaminoglycan（GAG） in the culture medium. Results PUS increased the secreting-type collagen and GAG from cell pellets compared with group N（P〈0.05）, whereas there was no difference in different intensities（P〉0.05）. PEMF had no significant effect on the secretion of the type of collagen（P〉0.05）. A PEMF of 1 mT had no significant effect on the secretion of GAG（P〉0.05）. A PEMF 2 and 5 mT decreased the secretion of GAG（P〈0.05）. Conclusion To prevent the secretary of extracellular matrix may play a role in chondrogenic effect of PEMF.