Pulse frequency dependency of photobiomodulation on the bioenergetic functions of human dental pulp stem cells

Photobiomodulation (PBM), also known as low-level laser (light) therapy, was discovered over 50 years ago, but only recently has it been making progress toward wide acceptance. PBM originally used red and near-infrared (NIR) lasers, but now other wavelengths and non-coherent light-emitting diodes (LEDs) are being explored. The almost complete lack of side effects makes the conduction of controlled clinical trials relatively easy. Laboratory research has mainly concentrated on mammalian cells (normal or cancer) in culture, and small rodents (mice and rats) as models of different diseases. A sizeable body of work was carried out in the 1970s and 1980s in Russia looking at various bacterial and fungal cells. The present review covers some of these studies and a recent number of papers that have applied PBM to so-called "model organisms." These models include flies (Drosophila), worms (Caenorhabditis elegans), fish (zebrafish) and caterpillars (Galleria). Much knowledge about the genomics and proteomics, and many reagents for these organisms already exist. They are inexpensive to work with and have lower regulatory barriers compared to vertebrate animals. Other researchers have studied different models (snails, sea urchins, Paramecium, toads, frogs and chickens). Plants may respond to NIR light differently from visible light (photosynthesis and photomorphogenesis) but PBM in plants has not been much studied. Veterinarians routinely use PBM to treat non-mammalian patients. The conclusion is that red or NIR light does indeed have significant biologic effects conserved over many different kingdoms, and perhaps it is true that "all life-forms respond to light."

show abstract

“…There have been several recent reports that PBM has significant effects on mitochondrial dynamics including both fission and fusion .…”

Section: Mechanisms Of Pbm Mitochondria and Plastidsmentioning

confidence: 99%

“…There have been several recent reports that PBM has significant effects on mitochondrial dynamics including both fission and fusion (41)(42)(43). Table 2 presents a list of the non-mammalian organisms and model organisms that have been used in PBM studies.…”

Section: Mechanisms Of Pbm Mitochondria and Plastidsmentioning

confidence: 99%

Non‐mammalian Hosts and Photobiomodulation: Do All Life‐forms Respond to Light?

Hamblin

Huang

Heiskanen

2018

Photochem & Photobiology

View full text Add to dashboard Cite

show abstract

“…Although we observed energy‐dependent efficacies (biphasic dose–response) on R‐PW 500 irradiation (peak at 0.25 J cm –2 , Figure 5A), PW 5 and PW 500 irradiations (either R or NIR) exhibited significantly different efficacies at same energy densities. In spite of the same energy density under different pulsed frequencies (i.e., PW 5 vs PW 500 ), cellular energy status (i.e., ATP level) could be different due to delayed luminescence that is the prolonged ultra‐weak luminescence emitted by the biological system after the light source is switched off 44–46. As the negative effect was mainly observed under LPS stimulus in this study, it is speculated that cell inflammation may affect cellular energy status under high‐frequency irradiance, thereby exhibiting negative effects.…”

Section: Discussionmentioning

confidence: 72%

A Comprehensive Analysis of Near‐Contact Photobiomodulation Therapy in the Host–Bacteria Interaction Model Using 3D‐Printed Modular LED Platform

et al. 2020

View full text Add to dashboard Cite

One well‐studied bacterial factor recognized by the host immune system is lipopolysaccharides (LPS) that stimulate host cells, resulting in cell inflammation. Although photobiomodulation (PBM) therapy demonstrates its potency on anti‐inflammatory activity, the complete mechanism of action in the host–bacteria interaction model is still elusive. In addition, many studies were performed regarding a distance between the light source and biological sample (non‐contact therapy) that may result in disparate reports on the efficacy of PBM therapy. Thus, it is critical to clearly understand the effect of this approach to maximize efficacy and minimize side effects. Here, a custom‐built light‐emitting diode (LED) platform that mimics near‐contact therapy is developed. The effect and mechanism of PBM therapy on epithelial cells in response to LPS is systematically investigated under various conditions (wavelength, irradiation‐time, pulse‐frequency). The data show that the irradiation of near‐infrared (NIR‐LED) significantly improves the viability of inflamed cells. It reveals that NIR‐LED inhibits the production of reactive oxygen species by regulating the Nox4‐NF‐κB pathway. Interestingly, however, high‐pulse frequency stimulus causes the collapse of the mitochondrial membrane potential (ΔΨm) of cells, resulting in cell death. These results suggest that the optimized “PBM condition” is critical to assist the healthy immune system of the host against bacterial invasion.

show abstract

“…Specifically, mechanical stimulation leveraged through hydrostatic pressure and shear stress can influence differentiation (Kelly & Prendergast, ). Similarly, optic and magnetic/electric modulation can be incorporated through bioreactor bioprocessing, limiting excessive use of biochemical signals (Kim, Baik, Choung, & Chung, ; Marycz, Kornicka, & Röcken, ). However, this tunability comes associated with countless design choices.…”

Section: Transport Propertiesmentioning

confidence: 99%

Engineering inkjet bioprinting processes toward translational therapies

Angelopoulos

Allenby

Lim³

et al. 2019

Biotech & Bioengineering

View full text Add to dashboard Cite

Bioprinting is the assembly of three‐dimensional (3D) tissue constructs by layering cell‐laden biomaterials using additive manufacturing techniques, offering great potential for tissue engineering and regenerative medicine. Such a process can be performed with high resolution and control by personalized or commercially available inkjet printers. However, bioprinting's clinical translation is significantly limited due to process engineering challenges. Upstream challenges include synthesis, cellular incorporation, and functionalization of “bioinks,” and extrusion of print geometries. Downstream challenges address sterilization, culture, implantation, and degradation. In the long run, bioinks must provide a microenvironment to support cell growth, development, and maturation and must interact and integrate with the surrounding tissues after implantation. Additionally, a robust, scaleable manufacturing process must pass regulatory scrutiny from regulatory bodies such as U.S. Food and Drug Administration, European Medicines Agency, or Australian Therapeutic Goods Administration for bioprinting to have a real clinical impact. In this review, recent advances in inkjet‐based 3D bioprinting will be presented, emphasizing on biomaterials available, their properties, and the process to generate bioprinted constructs with application in medicine. Current challenges and the future path of bioprinting and bioinks will be addressed, with emphasis in mass production aspects and the regulatory framework bioink‐based products must comply to translate this technology from the bench to the clinic.

show abstract

Pulse frequency dependency of photobiomodulation on the bioenergetic functions of human dental pulp stem cells

Cited by 37 publications

References 55 publications

Non‐mammalian Hosts and Photobiomodulation: Do All Life‐forms Respond to Light?

Non‐mammalian Hosts and Photobiomodulation: Do All Life‐forms Respond to Light?

A Comprehensive Analysis of Near‐Contact Photobiomodulation Therapy in the Host–Bacteria Interaction Model Using 3D‐Printed Modular LED Platform

Engineering inkjet bioprinting processes toward translational therapies

Contact Info

Product

Resources

About