Zohreh Bahadorloo - Department of Biology, Faculty of Sciences, Central Tehran Branch, Islamic Azad University, Tehran, Iran
Zeinab Piravar - Department of Biology, Faculty of Sciences, Central Tehran Branch, Islamic Azad University, Tehran, Iran
Jamshid Sabaghzadeh - Department of Physics, Faculty of Sciences, Central Tehran Branch, Islamic Azad University, Tehran, Iran

Background: Low-level laser therapy (LLLT), is a clinically well-established tool for wound healing. In vitro studies have shown that LLLT has abiostimulatory effect on mesenchymal lineages and non-mesenchymal lineages of Adipose-derived stem cells (ADSCs) differentiation. The aim of this study was to evaluate the effects of LLLT at different energy intensities on differentiation of (ADSCs) to keratinocyte.Methods: Adipose tissue were successfully obtained from ۴۵-year-old woman by Lipoaspirates and adipose-derived mesenchymal stem cells (ADSCs) were isolated. ADSCs were divided into a control group and three low-level laser treated groups irradiated with ۰.۵ J/cm۲, ۱ J/cm۲ and ۲ J/cm۲ laser doses using He-Ne laser with ۶۳۲nm wave length in ۵ times. All groups cultured with keratinocytes media for ۱۰-days. Cell proliferation was eveluated using ۳-(۴, ۵-dimethylthiazol-۲yl)-۲, ۵-diphenyltetrazolium bromide (MTT) assay. ADSCs developed a polygonal cobblestone shape characteristic of human keratinocytes. Specific keratinocyte marker ۵ (KRT۵) were analyzed by real-time PCR. Data were analyzed using one-way AVOVA and Tukey-Kramer hoc test by SPSS software version ۱۶.Results: Results of this study demonstrated LLLT could significantly affect proliferation of ADSCs (P<۰.۰۵) and promote ADSCs differentiation to keratinocytes by increasing expression of KRT۵ at of ۱ J/cm۲ and ۲ J/cm۲ laser doses (P<۰.۰۱). LLLT at density of ۰.۵ J/cm۲ could not promote ADSCs differentiation significantly.Conclusion: Considering these findings, LLLT could improve current in vitro methods of differentiating ADSCs to keratinocyte prior to transplantation. Thereby LLLT can use clinically as promoting skin wound healing.

Adipose-derived stem cells (ADSCs), Low-level laser therapy (LLLT), Differentiation, Keratinocyte, KRT۵