The Experimental Study On Effects Of Low-intensity Laser On The Length Of Telomere DNA

The study takes the human fetal lung diploid fibroblasts (2BS) cells cultured in vitro as cell senescence model to study effects of low-intensity He-Ne laser on Telomere DNA length. The samples were treated with low-intensity He-Ne laser by different irradiation time and different radiation power, to test the effects of low-intensity laser irradiation on the cell growth and proliferation by the method of MTT(3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltrazolium bromide), measuring the relative length of telomere DNA with q-PCR(the Quantitative Real-time Polymerase Chain Reaction). Results are as follows:(1) The cell growth and proliferation results of MTT array. After cells were treated with low-intensity laser, the cell growth rate is greater than the control group. This experiment here gives us one of important message that the low-intensity laser irradiation does not negatively affect cell growth, in contrary, it promotes the cell growth.(2) The results of measuring telomere length measured by q-PCR. In the control group, the length of telomere from the old cells is shorter than that from young cells (P<0.05). This result validates that telomere length becomes shorter when cells are aged. All that confirms that telomere is closely associated with the cell senescence. In the experimental group, the length of telomere from aged cells is longer than that from control group aged cells (P<0.05). The results of the present study reveal that the shortening rate of telomere length is reduced given adequate laser irradiation. The low-intensity irradiation may delay cell aging. This study provides an experimental basis to further investigate the effect of low-intensity laser on cell aging at the genetic level.It is the first time that the low-intensity laser has been applied to the human cells senescence model. q-PCR employed in this study supplies a simple, fast, highly specific and reproducible method to measure the telomere length. The study provides biophysical and molecular basis for low-intensity laser facilitates the delay of cells aging, as well as, a way to study the anti-aging mechanism of low-intensity laser in the genetic level. In the meantime, through experimentally filtering the valid biological value of laser parameter, the study provides new ways and new technologies in the terms of prolonging the cell life time and prevention age-related diseases.