Low Intensity Ultrasound, Proliferation & Growth Indexes in Adult Stem Cell

The aim of this study is to evaluate the effects of low intensity ultrasound (LIUS) on proliferation and growth indexes of rat Bone-Marrow mesenchymal stem cells (MSCs) in vitro.

Low intensity ultrasound was irradiated by Ip/IAve= 355 mW.cm-2 and 3 MHz frequency in continues mode. Bone marrow cells prepared from rat's tibia and femur central canal were cultured in medium complemented with FBS. Passage three confluent cells were irradiated by LIUS and during 7 days culture period proliferation and growth indexes of cells were evaluated by calculation of Population Doubling Number (PDN) and daily examination of the cell growth for drawing growth curve. Each experiment was performed three times for ten sample and the mean values were statistically compared by SPSS (16.0) software. In this study, passaged-3 cells were evaluated in terms of their bone and adipocyte differentiation potential.

According to growth curve, the cells affected by ultrasound, have short lag phase and their log phase was sharper and shorter than control group (without ultrasound treatment). In US group more population doubling number occurred (p<0.004); PD in US group was 17.3924±5.79 versus control group 14.087±4.69 (p<0.005). Passageed-3 cells were readily differentiated among bone and adipocyte lineages confirming their mesenchymal stem cell nature.

Taken together, we investigated that LIUS could significantly improve the proliferation and viability potential of rat MSCs in vitro.