Biphasic dose response in low level light therapy – an update
TLDR
Transcranial LLLT for traumatic brain injury in mice shows a distinct biphasic pattern with peaks in beneficial neurological effects observed when the number of treatments is varied, and when the energy density of an individual treatment is varied.Abstract:
Low-level laser (light) therapy (LLLT) has been known since 1967 but still remains controversial due to incomplete understanding of the basic mechanisms and the selection of inappropriate dosimetric parameters that led to negative studies. The biphasic dose-response or Arndt-Schulz curve in LLLT has been shown both in vitro studies and in animal experiments. This review will provide an update to our previous (Huang et al. 2009) coverage of this topic. In vitro mediators of LLLT such as adenosine triphosphate (ATP) and mitochondrial membrane potential show biphasic patterns, while others such as mitochondrial reactive oxygen species show a triphasic dose-response with two distinct peaks. The Janus nature of reactive oxygen species (ROS) that may act as a beneficial signaling molecule at low concentrations and a harmful cytotoxic agent at high concentrations, may partly explain the observed responses in vivo. Transcranial LLLT for traumatic brain injury (TBI) in mice shows a distinct biphasic pattern with peaks in beneficial neurological effects observed when the number of treatments is varied, and when the energy density of an individual treatment is varied. Further understanding of the extent to which biphasic dose responses apply in LLLT will be necessary to optimize clinical treatments.read more
Citations
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Journal ArticleDOI
The Nuts and Bolts of Low-level Laser (Light) Therapy
Hoon Chung,Tianhong Dai,Sulbha K. Sharma,Ying-Ying Huang,Ying-Ying Huang,James D. Carroll,Michael R. Hamblin,Michael R. Hamblin +7 more
TL;DR: The mechanisms of action of LLLT at a cellular and at a tissular level are covered and the various light sources and principles of dosimetry that are employed in clinical practice are summarized.
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Biphasic Dose Response in Low Level Light Therapy
TL;DR: The molecular and cellular mechanisms in LLLT are covered, and some of the recent results in vitro and in vivo that provide scientific explanations for this biphasic dose response are described.
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Proposed Mechanisms of Photobiomodulation or Low-Level Light Therapy
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TL;DR: Low-level laser (light) therapy (LLLT) is a fast-growing technology used to treat a multitude of conditions that require stimulation of healing, relief of pain and inflammation, and restoration of function.
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Mechanisms and applications of the anti-inflammatory effects of photobiomodulation.
TL;DR: One of the most reproducible effects of PBM is an overall reduction in inflammation, which is particularly important for disorders of the joints, traumatic injuries, lung disorders, and in the brain.
References
More filters
Journal ArticleDOI
NF-κB at the crossroads of life and death
Michael Karin,Anning Lin +1 more
TL;DR: The choice between life and death is one of the major events in regulation of the immune system and a major regulator of such life or death decisions is the transcription factor NF-κB as mentioned in this paper.
Journal ArticleDOI
Primary and secondary mechanisms of action of visible to near-IR radiation on cells.
TL;DR: A cascade of reactions connected with alteration in cellular homeostasis parameters (pHi, [Cai], cAMP, Eh, [ATP] and some others) is considered as a photosignal transduction and amplification chain in a cell (secondary mechanisms).
Journal ArticleDOI
Biphasic Dose Response in Low Level Light Therapy
TL;DR: The molecular and cellular mechanisms in LLLT are covered, and some of the recent results in vitro and in vivo that provide scientific explanations for this biphasic dose response are described.
Journal ArticleDOI
A systematic review of low level laser therapy with location-specific doses for pain from chronic joint disorders.
TL;DR: Low level laser therapy with the suggested dose range significantly reduces pain and improves health status in chronic joint disorders, but the heterogeneity in patient samples, treatment procedures and trial design calls for cautious interpretation of the results.
Journal ArticleDOI
Exact action spectra for cellular responses relevant to phototherapy.
Tiina I. Karu,Sergei F. Kolyakov +1 more
TL;DR: In the wavelength range important for phototherapy (600-860 nm), there are four "active" regions, but peak positions are not exactly the same for all spectra, so exact parameters of peak positions and bandwidths are presented.