Effect of red and near-infrared irradiation on periodontal ligament stem cells: ROS generation and cell cycle analysis

Abstract

Reconstruction of lost tooth structures and the periodontium with the help of tissue engineering has found a special place in dentistry in recent years with reports of great therapeutic success. Stem cells from the periodontal ligament have the potential for high differentiation into the bone and periodontal ligament cells and are therefore a suit candidate for regenerative therapies of the periodontium and other tissues. In this regard, the use of photobiomodulation on these cells by light irradiation can be effective in increasing the efficiency of these regenerative methods. The effect of red and near-infrared lasers was investigated in pulsed and continuous modes on the cell viability, ROS production and the cell cycle of Periodontal Ligament Stem cells (PDLSCs) using MTT assay and flowcytometry techniques. The result shows that both red and near-infra-red (NIR) irradiations at 3 J/cm² maintain cell viability. ROS generation assay indicated that in PDL stem cells irradiated with NIR laser (940 nm), ROS production was greater than in the red (660 nm) irradiated groups. Cell cycle analysis revealed that NIR irradiation can enhance the proportion of S-phase cells and declinedecline the proportion of G1-phase cells compared to the red laser irradiation groups. Moreover, this enhancement was greater in the pulsed group compared to the continuous mode group. Overall, the current study results showed that photobiomodulation can support the cell viability of PDLSCs and could affect the ROS production and cell cycle. This effect was more with 940 nm (NIR) irradiation pulsed mode compared to 660 nm (red).

Communicated by Ramaswamy H. Sarma

Keywords:

• Periodontal ligament stem cells (PDLSCs)
• photobiomodulation
• irradiation mode
• ROS generation
• cell cycle

Authors’ contributions

K.K. (Khatereh Khorsandi) and LG (Leila Gholami) designed and supervised the experiments; KK and LG conducted experiments; K.K. and L.G. analyzed the data and provided major contributions in writing the manuscript. LG, KK, and RF (Reza Fekrazad) reviewed & edit the final version. All authors read and approved the final manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Ethics approval and consent to participate

This article does not contain any studies with human participants or animals performed by any of the authors.

Availability of data and material

The data used to support the findings of this study are included in the article.

Additional information

Funding

The current study was funded by Hamadan University of medical sciences. (Grant number: 9907154914).