Improved healing and macrophage polarization in oral ulcers treated with photobiomodulation (PBM)

Abstract

Objectives: The effect of photobiomodulation (PBM) treatment on wound healing and macrophage polarization was investigated in vivo. Animal models of oral ulcers were simulated through chemically induced oral ulcers in rats. Materials and Methods: PBM treatment using an infrared pulsed laser was used to treat oral ulcers in the animal models. Twelve Sprague-Dawley rats were randomly divided into four groups depending on set absorbed energy: Group 1 (control), Group 2 (30 J), Group 3 (60 J), and Group 4 (100 J). Laser treatment was performed every other day for 8 days after ulcer confirmation. Parameters used were as follows: wavelength 808 nm, power output 50 mW, spot size 10 mm, frequency 10 Hz, and pulse duration 1 millisecond. Ulcers were measured to determine the effect of the treatments over time. Histology, immunostaining, and real-time polymerase chain reaction analyses were performed to evaluate the effect of PBM treatment on macrophage-related (IL-6/IL-10) and wound-healingrelated (TNF-α/TGF-β/MMP-2) cytokine expression. Results: Histological examinations indicate that the PBM treatment stimulated a higher level of wound recovery after 8 days of treatment at 60 J absorbed energy compared to other treatment groups. Analyses of relative gene expression of proinflammatory, anti-inflammatory, and tissue remodeling cytokines indicate that the macrophages in the tissue samples were predominantly characterized as M2 subtypes (alternatively activated), which possibly accounts for the accelerated tissue repair in the animal model of oral ulcer. Conclusion: This preliminary study stands as a proof of concept regarding the potential use of infrared laser PBM treatment for oral ulcers which have not been previously investigated upon. PBM treatment affects macrophage polarization and enhances wound healing. Further experimentation will be conducted to expand the understanding of how PBM treatment affects the healing mechanism of ulcers.

Inflammation in obsessive–compulsive disorder: A literature review and hypothesis‐based potential of transcranial photobiomodulation

“…1. t-PBM could balance the alterations in peripheral immune cell populations observed in OCD, such as dysregulation of Th17, Treg, monocytes, and the NLRP3 inflammasome complex (Choi et al, 2012;de Barros Silva et al, 2022;de Brito et al, 2022;Guo et al, 2021;Li, Liang, et al, 2020;Ryu et al, 2022;Wu et al, 2022); and modulate the motor cortex (Chaieb et al, 2015;Konstantinović et al, 2013;Song et al, 2020). Furthermore, motor response inhibition, interference control (van Velzen et al, 2014), and increased functional connectivity involving the pre-SMA (Tomiyama et al, 2021) have been observed in patients with OCD.…”

“…Research has suggested that the above‐mentioned mechanisms of t‐PBM may impact the pathophysiology of neuropsychiatric disorders via (1) modulation of oxidative stress (de Freitas & Hamblin, 2016; Molendijk et al., 2014; Rizzi et al., 2006); (2) downregulation of immune cell alterations and the NLRP3 inflammasome complex (Choi et al., 2012; de Barros Silva et al., 2022; de Brito et al., 2022; Guo et al., 2021; Li, Liang, et al., 2020; Ryu et al., 2022; Wu et al., 2022); (3) reduction of proinflammatory cytokines levels such as TNF‐α, CRP, IL‐1β, and IL‐6 (De Marchi et al., 2021; Esteves et al., 2022; Lima et al., 2014; Lu et al., 2017; Shaikh‐Kader et al., 2021; Zheng et al., 2021); (4) deactivation of neurotoxic microglia (Choi et al., 2012; Ketz et al., 2017; Lu et al., 2017; Tao et al., 2021; Wang et al., 2021), and (5) increase of BDNF gene expression (Heo et al., 2019; Yan et al., 2017).…”

“…If successful, t‐PBM could significantly improve the quality of life for patients with OCD. Moreover, the safety, low cost, and effectiveness of t‐PBM in other neuropsychiatric disorders (Ahrabi et al., 2022; Caldieraro & Cassano, 2019; Cassano et al., 2015, 2018, 2022; Dos Santos Cardoso et al., 2020; Liebert et al., 2021; Lopes Martins et al., 2021; Mannu et al., 2019; Naeser et al., 2014; O'Donnell et al., 2022; Poiani et al., 2018; Vieira, Gersten, et al., 2023; Vieira, Iosifescu, et al., 2023) as well as its ability to modulate inflammation (Choi et al., 2012; de Barros Silva et al., 2022; de Brito et al., 2022; De Marchi et al., 2021; Esteves et al., 2022; Guo et al., 2021; Ketz et al., 2017; Li, Liang, et al., 2020; Lima et al., 2014; Lu et al., 2017; Ryu et al., 2022; Shaikh‐Kader et al., 2021; Tao et al., 2021; Wang et al., 2021; Wu et al., 2022; Zheng et al., 2021) suggest that t‐PBM could be a valuable addition to the current treatment options for OCD.…”

“… t‐PBM could balance the alterations in peripheral immune cell populations observed in OCD, such as dysregulation of Th17, Treg, monocytes, and the NLRP3 inflammasome complex (Choi et al., 2012; de Barros Silva et al., 2022; de Brito et al., 2022; Guo et al., 2021; Li, Liang, et al., 2020; Ryu et al., 2022; Wu et al., 2022); t‐PBM could decrease the levels of peripheral cytokines that are elevated in OCD, including TNF‐α, CRP, IL‐1β, and IL‐6 (De Marchi et al., 2021; Esteves et al., 2022; Lima et al., 2014; Lu et al., 2017; Shaikh‐Kader et al., 2021; Zheng et al., 2021); t‐PBM could reduce neuroinflammation by decreasing the levels of the aforementioned inflammatory markers (De Marchi et al., 2021; Esteves et al., 2022; Lima et al., 2014; Lu et al., 2017; Shaikh‐Kader et al., 2021; Zheng et al., 2021), as well as the activation of neurotoxic microglia (Choi et al., 2012; Ketz et al., 2017; Lu et al., 2017; Tao et al., 2021; Wang et al., 2021). …”

Effect of Flaxseed on TGF-Β, IL-6, and MMP9 Genes Expression during Wound Healing Process in Rabbits

“…In different stages of wound healing, multiple biomarkers work in the orchestra to facilitate the process and advance the healing to the next stage. For example, anti-inflammatory markers such as Transforming growth factor-beta (TGF-β) aid to reduce inflammation and advancing the wound to the proliferation stage [9]. In the first part of our study, we aimed to explore the molecular effect of flaxseed oil on wound healing.…”