Article: Mechanisms of Low Level Light Therapy
Author: Michael R. Hamblin of Harvard Medical School
Highlights: Mitochondria are thought to be a likely site for the initial effects of light, leading to increased ATP production, modulation of reactive oxygen species, and induction of transcription factors. These effects in turn lead to increased cell proliferation and migration (particularly by fibroblasts), modulation in levels of cytokines, growth factors and inflammatory mediators, and increased tissue oxygenation. The results of these biochemical and cellular changes in animals and patients include such benefits as increased healing of chronic wounds, improvements in sports injuries and carpal tunnel syndrome, pain reduction in arthritis and neuropathies, and amelioration of damage after heart attacks, stroke, nerve injury, and retinal toxicity. (from the 2nd paragraph)
In LLLT, the question is no longer whether light has biological effects, but rather how energy from therapeutic lasers and LEDs work at the cellular and organism levels, and what are the optimal light parameters for different uses of these light sources. (under section 1, History)
There are perhaps three main areas of medicine and veterinary practice where LLT has a major role to play (Figure 1). These are (i) wound healing, tissue repair and prevention of tissue death; (ii) relief of inflammation in chronic diseases and injuries with its associated pain and edema; (iii) relief of neurogenic pain and some neurological problems. (under section 3. BIOCHEMICAL MECHANISMS)
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