Effects of shock wave on c-Fos and c-Jun protein expression in bone marrow mesenchymal stem cells / 中国组织工程研究

ABSTRACT

BACKGROUND: Now, Shock Wave Therapy is used to cure the ununion and delayed union of bone, the avascular necrosis of the femoral head and the chronic injury of locomotor system, what has got a good curative effect. But, the mechanism is not clear. OBJECTIVE: To investigate the expression of c-Fos, c-Jun protein in human bone marrow mesenchymal stem cells (BMSCs) Influenced by shock wave.DESIGN, TIME AND SETTING: Randomized group, the controlled study was performed at the State Key Laboratory of Pathology, College of Basic Medicine, Jilin University, from March 2007 to March 2008. MATERIALS Bone marrow was obtained from healthy volunteers.METHODS: Human BMSCs were cultured in vitro. And the fourth generation cells were digested into cell suspension with 2.5 g/L trypsin and adjusted at a density of 1.0×10~9/L with DMEM-LG. Then, the cells were divided into 6 1.5-mL Eerrendorf tubes, one was control group and the other five were experimental groups. The experimental groups were treated with an optimal dose of shock wave (8.5 kV, 120 times) by liquid-electric shock wave lithotripsy. Then the protein was extracted at different time points (5, 15, 30 minutes, 1, 2 hours) after treatment.MAIN OUTCOME MEASURES: Inverted microscope was used to observe the morphologic feature of BMSCs. The growth curves were charted by MTT method. The change of activations of c-Fos, c-Jun were tested by western blot. RESULTS: ①BMSCs were seeded in culture plate. The cells began to divide and proliferate slowly 24 hours later, and became fusiform shape after adhering to the wall. 3 days later, the speed of proliferation quickened, and cells accumulated colony. At day 10-14, the number of hMSCs grew till they covered the bottom of the culture plate. The round passage hMSCs adhered to the wall completely in 24 hours, which were similar to primary cells. The cells connected together during one week, and showed vortex-like. The speed of proliferation became slower and the cells became older when hMSCs were passaged to the tenth generation. ②MTT method showed that the growth curve of original, P2, P3 hMSCs looked like S shape, and the third to fifth days were growing period. ③The phosphorylation level of c-Fos and c-Jun began to increase after induced by shock wave and reached a peak at 30 and 15 minutes, respectively. And their phosphorylation level were 2.56-fold and 1.68-fold (P < 0.01) compared with the average level in control groups, respectively. Then they began to decrease. There was no apparent change in the total dose (P > 0.05). CONCLUSION: Following the treatment of shock wave, the activations of c-Fos and c-Jun in BMSCs increased.