ABSTRACT
Objective To investigate the effect of infrasound on the growth of bone marrow mescenchymal stem cells (BMSCs) and seek the most reasonable duration for using infrasound. Methods The primary BMSCs were obtained from Sprague-Dawley rats through whole bone marrow adherent cultivation.The cells of passage 3 were divided into trial groups treated with infrasound for 10 min,30 min or 60 min,and control groups which were not treated with infrasound but exposed to air for the same durations.The vitality of cell proliferation was measured using the CCK8 method.Apoptosis and the cell cycle were analysed with flow cytometry (FACS). Results After cultivation for 72 h,the optical density (OD) values for BMSCs treated with infrasound for 10 min,30 min and 60 min were 1.480 ± 0.030,1.348 ± 0.030,1.493 ± 0.030 respectively and after 96 h they were 1.774 ± 0.030,1.731 ± 0.030 and 1.833 ± 0.030.All of which were significantly greater than in the control groups ( 1.479 ± 0.030,1.267 ±0.030 and 1.227 ± 0.030 after 72 h and 1.567 ± 0.030,1.563 ± 0.030 and 1.632 ± 0.030 after 96 h).With the extension of the treatment duration,the OD values of the BMSCs increased or increased after decreasing,and the OD value for BMSCs treated with infrasound for 60 min was the highest.The FACS results indicated no effect of infrasound on apoptosis of BMSCs when the treatment duration was 30 min,but that cell apoptosis could be inhibited when the treatment duration was 10 min or 60 min.The early phase apoptosis rates were 1.07％ ± 0.12％ and 0.97％ ±0.21％ in the trial groups treated for 10 min and 60 min respectively,and 1.43％ ± 0.06％ and 3.33％ ± 0.15％ in the respective control groups,a highly significant difference.The results of cell cycle analysis showed infrasound could disturb the cell division of BMSCs significantly when the treatment duration was less than 30 min,but there was no significant effect when the treatment duration was 60 min. Conclusions Infrasound can promote cell proliferation and disturb cell division,but it did not cause apoptosis of BMSCs.When the treatment duration was 60 min,cell proliferation improved steadily,the apoptosis rate decreased,and the cell cycle did not change.So 60 min is the most reasonable treatment duration for infrasound.