Proteomic Analysis Reveals Anti-Fibrotic Effects of Blue Light Photobiomodulation on Fibroblasts

Combinatorial prophylactic effect of phlorotannins with photobiomodulation against tracheal stenosis

Several conventional treatments are used to manage tracheal stenosis after intubation and surgical procedures; however, patients are at risk of restenosis because of the absence of effective preventative therapy. In this study, we evaluate the biomodulatory effect of PT-combined blue light (BL) PBM in tracheostomal stenosis-induced animal models. The PT-combined BL group showed a significant decrease in the fibrotic protein synthesis by downregulating the release of stenosis-triggering fibrotic signals, without cytotoxicity or thermal damage. Moreover, the combined treatment ameliorated excessive granulation and collagen formation, and consequently preserved the opening of the tracheostoma ten days after fenestration. The current study demonstrated the biomodulatory effect of PT-combined BL on human tracheal fibroblasts and tracheal fenestration rodent models. Hence, PT-combined BL has the potential to be an effective preventative treatment for tracheal stenosis but also as an alternative option for fibrotic disorders.

CK2 Regulation: Perspectives in 2021

The protein kinase CK2 (CK2) family encompasses a small number of acidophilic serine/threonine kinases that phosphorylate substrates involved in numerous biological processes including apoptosis, cell proliferation, and the DNA damage response. CK2 has also been implicated in many human malignancies and other disorders including Alzheimer′s and Parkinson’s diseases, and COVID-19. Interestingly, no single mechanism describes how CK2 is regulated, including activation by external proteins or domains, phosphorylation, or dimerization. Furthermore, the kinase has an elongated activation loop that locks the kinase into an active conformation, leading CK2 to be labelled a constitutively active kinase. This presents an interesting paradox that remains unanswered: how can a constitutively active kinase regulate biological processes that require careful control? Here, we highlight a selection of studies where CK2 activity is regulated at the substrate level, and discuss them based on the regulatory mechanism. Overall, this review describes numerous biological processes where CK2 activity is regulated, highlighting how a constitutively active kinase can still control numerous cellular activities. It is also evident that more research is required to fully elucidate the mechanisms that regulate CK2 and what causes aberrant CK2 signaling in disease.

Light-emitting diode stimulates radiodermatitis recovery

Purpose

To evaluate the effect of light-emitting diode (LED) in an experimental model of radiodermatitis.

Methods

Ten male Wistar rats weighing 200–250 g were analyzed. Radiation was delivered in a single dose (20 Gy with Strontium-90 dermatological plaques), two areas per animal. After 15 days, they were divided into two groups: control group (n = 5) and LED group (n = 5), which was treated during 21 days later (LED 660 nm, 10 min in alternate days). The endpoints were radiodermatitis scale, histological analysis HE, Picrius Sirius and the gene expression of interleukin-10 (IL-10) and matrix metalloproteinase-9 (MMP-9).

Results

The LED group showed a higher number of dermal appendages (p = 0.04) and angiogenesis(p = 0.007), a tendency towards higher IL-10 (p = 0.06) and an increase in MMP-9 (p = 0.004) when compared to the control group.

Conclusions

This study suggested that the use of LED for radiodermatitis increased skin regeneration.

In Vitro Evidences of Different Fibroblast Morpho-Functional Responses to Red, Near-Infrared and Violet-Blue Photobiomodulation: Clues for Addressing Wound Healing

Although photobiomodulation (PBM) has proven promising to treat wounds, the lack of univocal guidelines and of a thorough understanding of light–tissue interactions hampers its mainstream adoption for wound healing promotion. This study compared murine and human fibroblast responses to PBM by red (635 ± 5 nm), near-infrared (NIR, 808 ± 1 nm), and violet-blue (405 ± 5 nm) light (0.4 J/cm2 energy density, 13 mW/cm2 power density). Cell viability was not altered by PBM treatments. Light and confocal laser scanning microscopy and biochemical analyses showed, in red PBM irradiated cells: F-actin assembly reduction, up-regulated expression of Ki67 proliferation marker and of vinculin in focal adhesions, type-1 collagen down-regulation, matrix metalloproteinase-2 and metalloproteinase-9 expression/functionality increase concomitant to their inhibitors (TIMP-1 and TIMP-2) decrease. Violet-blue and even more NIR PBM stimulated collagen expression/deposition and, likely, cell differentiation towards (proto)myofibroblast phenotype. Indeed, these cells exhibited a higher polygonal surface area, stress fiber-like structures, increased vinculin- and phospho-focal adhesion kinase-rich clusters and α-smooth muscle actin. This study may provide the experimental groundwork to support red, NIR, and violet-blue PBM as potential options to promote proliferative and matrix remodeling/maturation phases of wound healing, targeting fibroblasts, and to suggest the use of combined PBM treatments in the wound management setting.

Assessment of the Photobiomodulation Effect of a Blue Diode Laser on the Proliferation and Migration of Cultured Human Gingival Fibroblast Cells: A Preliminary In Vitro Study

Introduction: Photobiomodulation therapy (PBM) is emerging as an effective strategy for the management of wound healing. The application of red and near infra-red light sources in laser therapy has been the subject of most researches in recent literature. Considering the lack of sufficient evidence in assessing the blue light in PBM, we aimed to investigate the photobiomodulation effect of a blue diode laser on the proliferation and migration of cultured human gingival fibroblast cells as a preliminary in vitro study. Methods: Human gingival fibroblast cells were irradiated with a blue diode laser at a 445 nm wavelength. Irradiation was done using three different powers of 200 mW (irradiation times of 5, 10,15, and 20 seconds); 300 mW (irradiation times of 5, 10, and 15 seconds); and 400 mW (irradiation times of 5 and 10 seconds). The fibroblast cells without laser exposure were considered as control. After 24 hours of incubation, the MTT assay and the wound scratch test were performed on the cells to investigate the biomodulation effect of the blue laser on the proliferation and migration of the cells respectively. The results were analyzed by one-way ANOVA and a post-hoc Tukey test with a P value <0.05 as a statistical significance level. Results: PBM with blue diode laser at power densities of 400 mW/cm² with irradiation times of 10 and 15 seconds corresponding to energy densities of 4 and 6 J/cm² exerted the statistically significant positive effect on both proliferation and migration of gingival fibroblast cells. Conclusion: Considering the encouraging findings of this study, PBM with blue diode laser can promote proliferation and migration of human gingival fibroblasts, the key cells involved in the process of oral wound healing.