Pre-conditioning with low-level laser (light) therapy: light before the storm. Author: Agrawal T1, Gupta GK2, Rai V3, Carroll JD4, Hamblin MR5. Affiliation: 1The Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114; ; Department of Dermatology, Harvard Medical School, Boston, MA 02115; 2The Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114; ; Department of Dermatology, Harvard Medical School, Boston, MA 02115; ; Department of Pathology and Laboratory Medicine, Tufts Medical Center, Boston, MA, 02111; 3Wilf Family Cardiovascular Research Institute, Division of Cardiology, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461; 4THOR Photomedicine Ltd, 18A East Street, Chesham, HP5 1HQ, UK; 5The Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114; ; Department of Dermatology, Harvard Medical School, Boston, MA 02115; ; Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA 02139. Conference/Journal: Dose Response. Date published: 2014 Sep 22 Other: Volume ID: 12 , Issue ID: 4 , Pages: 619-49 , Special Notes: doi: 10.2203/dose-response.14-032.Agrawal. eCollection 2014. , Word Count: 221 Pre-conditioning by ischemia, hyperthermia, hypothermia, hyperbaric oxygen (and numerous other modalities) is a rapidly growing area of investigation that is used in pathological conditions where tissue damage may be expected. The damage caused by surgery, heart attack, or stroke can be mitigated by pre-treating the local or distant tissue with low levels of a stress-inducing stimulus, that can induce a protective response against subsequent major damage. Low-level laser (light) therapy (LLLT) has been used for nearly 50 years to enhance tissue healing and to relieve pain, inflammation and swelling. The photons are absorbed in cytochrome(c) oxidase (unit four in the mitochondrial respiratory chain), and this enzyme activation increases electron transport, respiration, oxygen consumption and ATP production. A complex signaling cascade is initiated leading to activation of transcription factors and up- and down-regulation of numerous genes. Recently it has become apparent that LLLT can also be effective if delivered to normal cells or tissue before the actual insult or trauma, in a pre-conditioning mode. Muscles are protected, nerves feel less pain, and LLLT can protect against a subsequent heart attack. These examples point the way to wider use of LLLT as a pre-conditioning modality to prevent pain and increase healing after surgical/medical procedures and possibly to increase athletic performance. KEYWORDS: LLLT; Mitochondria; Photobiomodulation; Pre-conditioning; Reactive Oxygen Species; Remote Ischemic Pre-conditioning PMID: 25552961