Evaluation of the effect of low-level laser irradiation on viability and ROS production in human hair follicle stem cells

Background: Low-level lasers are used for various medical applications including wound healing and hair loss treatment. Cell Therapy using skin stem cells could be a novel approach to hair transplantation. However, there is no study on the effect of low-level laser on the hair follicle stem cells. So, in this study, we investigated the effect of low level laser irradiation on viability and ROS production in the hair follicle stem cells. Methods: This study was performed in the cell culture laboratory of Medical Laser Research Center, Yara Institute in 2020 (June 2020 to February 2020). The hair follicle was isolated from the Safe Donor Area (SDA) using the 4mm punch method. In the laboratory, after separating the follicular units, the bulb region of each follicle was isolated via mechanical and enzymatic methods and cultured in FBS+F12-DMEM. Afterward, the stem cells were characterized via flow cytometry. The effect of low-level laser (685 nm) with different doses (1-20 J/cm2) was investigated on cell proliferation, viability and ROS production. Results: The stem cells were confirmed via flow cytometry and also morphological tests. The results indicated that the viability of the stem cells under laser irradiation was different. comparison of the cell viability before and after laser irradiation showed that the highest viability was related to 5 J/cm2 dose energy of laser irradiation. However, the viability of the cells in most dose energy of laser irradiation increased compared with the control group. Moreover, ROS production had a significant increase on 5 J/cm2 energy density of laser irradiation. We can be achieved better treatment in hair transplantation and hair follicle growth by knowing the effect of low-level laser irradiation on the viability of the hair follicle stem cells. Conclusion: The result of this study could be useful in cell therapy and hair transplantation due to the improvement of cell viability and increase in ROS production under the influence of laser irradiation.