Photoactivation of bone marrow mesenchymal stromal cells with diode laser: Effects and mechanisms of action

Abstract

Mesenchymal stromal cells (MSCs) are a promising cell candidate in tissue engineering and regenerative medicine. Their proliferative potential can be increased by low-level laser irradiation (LLLI), but the mechanisms involved remain to be clarified. With the aim of expanding the therapeutic application of LLLI to MSC therapy, in the present study we investigated the effects of 635 nm diode laser on mouse MSC proliferation and investigated the underlying cellular and molecular mechanisms, focusing the attention on the effects of laser irradiation on Notch-1 signal activation and membrane ion channel modulation. It was found that MSC proliferation was significantly enhanced after laser irradiation, as judged by time lapse videomicroscopy and EdU incorporation. This phenomenon was associated with the up-regulation and activation of Notch-1 pathway, and with increased membrane conductance through voltage-gated K(+) , BK and Kir, channels and T- and L-type Ca(2+) channels. We also showed that MSC proliferation was mainly dependent on Kir channel activity, on the basis that the cell growth and Notch-1 up-regulation were severely decreased by the pre-treatment with the channel inhibitor Ba(2+) (0.5 mM). Interestingly, the channel inhibition was also able to attenuate the stimulatory effects of diode laser on MSCs, thus providing novel evidence to expand our knowledge on the mechanisms of biostimulation after LLLI. In conclusions, our findings suggest that diode laser may be a valid approach for the preconditioning of MSCs in vitro prior cell transplantation.

The effect of MLS laser radiation on cell lipid membrane

“…Also, Giannelli et al [23] studied the influence of laser radiation (635 nm, 0.89W) on cells, particularly on proliferative mechanisms of mesenchymal stromal cells (MSCs). The researchers confirmed the increase of MSCs proliferation connected with activating of the Notch-I path and increased permeability of cell membrane for K + ions and T-and L-type calcium (Ca 2+ ) channels.…”

The influence of continuous low-intensity laser radiation at the red (635 nm) and green (525 nm) wavelengths on the human mesenchymal stem cells in vitro: a review of the literature and original investigations

“…Несмотря на значительный разброс энергетиче-ских параметров лазерного воздействия в исследо-ваниях по изучению влияния НИЛИ на пролифера-цию МСК, данные литературы в отношении опти-мальной ЭП для непрерывного НИЛИ с длиной волны 633-635 нм находятся в достаточно узком диапазоне -0,3-0,5 Дж/см 2 , при этом ПМ варьи-рует в значительно более широких пределах, от 3-6,61 мВт/см 2 [18][19][20][21][22][23] a -фотография клеток в проходящем свете. Ув.…”

The application of stem cells, visible and infrared light in regenerative medicine. Part 1

“…[34] на МСККМ не было включено в графический анализ. Из статьи непонятно, какому значению плотности мощности и времени экспозиции соответствует заяв-ленная прибавка скорости пролиферации (в табл.…”