Les résultats de ces changements biochimiques et cellulaires des animaux et des patients incluent des avantages tels que la guérison accrue dans les blessures chroniques, les améliorations dans des dommages de sports et le syndrome de tunnel de carpal, la réduction de douleur de l’arthrite et des neuropathies, et l’amélioration des dommages après les crises cardiaques, la course, les dommages de nerf et la toxicité rétinienne.
Mechanisms of Low Level Light Therapy
HAMBLIN Michael R., Massachusetts General Hospital and Harvard Medical School and Harvard-MIT
DEMIDOVA Tatiana N., Massachusetts General Hospital and Tufts Univ. School of Medicine
Progress in biomedical optics and imaging, 2006, vol. 7, no26, [Note(s): 614001.1-614001.12]
Theuse of low levels of visible or near infrared lightfor reducing pain, inflammation and edema, promoting healing of wounds,deeper tissues and nerves, and preventing tissue damage has beenknown for almost forty years since the invention of lasers.Originally thought to be a peculiar property of laser light(soft or cold lasers), the subject has now broadened toinclude photobiomodulation and photobiostimulation using non-coherent light. Despite many reportsof positive findings from experiments conducted in vitro, in animalmodels and in randomized controlled clinical trials, LLLT remains controversial.This likely is due to two main reasons; firstly thebiochemical mechanisms underlying the positive effects are incompletely understood, andsecondly the complexity of rationally choosing amongst a large numberof illumination parameters such as wavelength, fluence, power density, pulsestructure and treatment timing has led to the publication ofa number of negative studies as well as many positiveones. In particular a biphasic dose response has been frequentlyobserved where low levels of light have a much bettereffect than higher levels. This introductory review will cover someof the proposed cellular chromophores responsible for the effect ofvisible light on mammalian cells, including cytochrome c oxidase (withabsorption peaks in the near infrared) and photoactive porphyrins. Mitochondriaare thought to be a likely site for the initialeffects of light, leading to increased ATP production, modulation ofreactive oxygen species and induction of transcription factors. These effectsin turn lead to increased cell proliferation and migration (particularlyby fibroblasts), modulation in levels of cytokines, growth factors andinflammatory mediators, and increased tissue oxygenation. The results of thesebiochemical and cellular changes in animals and patients include suchbenefits as increased healing in chronic wounds, improvements in sportsinjuries and carpal tunnel syndrome, pain reduction in arthritis andneuropathies, and amelioration of damage after heart attacks, stroke, nerveinjury and retinal toxicity.