title: Red and Infrared Low-Level Laser Therapy Prior to Injury with or without Administration after Injury Modulate Oxidative Stress during the Muscle Repair Process.
abstract: BACKGROUND
  Muscle injury is common among athletes and amateur practitioners of sports. Following an injury, the production of reactive oxygen species (ROS) occurs, which can harm healthy muscle fibers (secondary damage) and delay the repair process. Low-level laser therapy (LLLT) administered prior to or following an injury has demonstrated positive and protective effects on muscle repair, but the combination of both administration times together has not been clarified.
  
  
  OBJECTIVE
  To evaluate the effect of LLLT (660 nm and 780 nm, 10 J/cm², 40 mW, 3.2 J) prior to injury with or without the administration after injury on oxidative stress during the muscle repair process.
  
  
  METHODS
  Wistar rats were divided into following groups: control; muscle injury alone; LLLT 660 nm + injury; LLLT 780 nm + injury; LLLT 660 nm before and after injury; and LLLT 780 nm before and after injury. The rats were euthanized on days 1, 3 and 7 following cryoinjury of the tibialis anterior (TA) muscle, which was then removed for analysis.
  
  
  RESULTS
  Lipid peroxidation decreased in the 660+injury group after one day. Moreover, red and infrared LLLT employed at both administration times induced a decrease in lipid peroxidation after seven days. CAT activity was altered by LLLT in all periods evaluated, with a decrease after one day in the 780+injury+780 group and after seven days in the 780+injury group as well as an increase in the 780+injury and 780+injury+780 groups after three days. Furthermore, increases in GPx and SOD activity were found after seven days in the 780+injury+780 group.
  
  
  CONCLUSIONS
  The administration of red and infrared laser therapy at different times positively modulates the activity of antioxidant enzymes and reduces stress markers during the muscle repair process.
authors.affiliation: Rehabilitation Department, Universidade Nove de Julho (UNINOVE), São Paulo, SP, Brazil.
authors.forename: Beatriz Guimarães
authors.initials: BG
authors.lastname: Ribeiro
authors.affiliation: Rehabilitation Department, Universidade Nove de Julho (UNINOVE), São Paulo, SP, Brazil.
authors.forename: Agnelo Neves
authors.initials: AN
authors.lastname: Alves
authors.affiliation: Biophotonics Department, Universidade Nove de Julho (UNINOVE), São Paulo, SP, Brazil.
authors.forename: Lucas Andreo Dias
authors.initials: LA
authors.lastname: Dos Santos
authors.affiliation: Rehabilitation Department, Universidade Nove de Julho (UNINOVE), São Paulo, SP, Brazil.
authors.forename: Tatiane Matarazzo
authors.initials: TM
authors.lastname: Cantero
authors.affiliation: Biophotonics Department, Universidade Nove de Julho (UNINOVE), São Paulo, SP, Brazil.
authors.forename: Kristianne Porta Santos
authors.initials: KP
authors.lastname: Fernandes
authors.affiliation: Rehabilitation Department, Universidade Nove de Julho (UNINOVE), São Paulo, SP, Brazil.
authors.forename: Danielle da Silva
authors.initials: Dda S
authors.lastname: Dias
authors.affiliation: Hypertension Unit, Heart Institute (InCor), School of Medicine, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Nathalia
authors.initials: N
authors.lastname: Bernardes
authors.affiliation: Rehabilitation Department, Universidade Nove de Julho (UNINOVE), São Paulo, SP, Brazil.|Medicine Department, Universidade Nove de Julho (UNINOVE), São Paulo, SP, Brazil.
authors.forename: Kátia
authors.initials: K
authors.lastname: De Angelis
authors.affiliation: Rehabilitation Department, Universidade Nove de Julho (UNINOVE), São Paulo, SP, Brazil.|Biophotonics Department, Universidade Nove de Julho (UNINOVE), São Paulo, SP, Brazil.
authors.forename: Raquel Agnelli
authors.initials: RA
authors.lastname: Mesquita-Ferrari
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D007259:Infrared Rays; D015227:Lipid Peroxidation; D028022:Low-Level Light Therapy / Q000379:methods*; D018482:Muscle, Skeletal / Q000293:injuries / Q000502:physiology*; D018384:Oxidative Stress; D010100:Oxygen / Q000737:chemistry; D051381:Rats; D017208:Rats, Wistar; D012038:Regeneration; D013482:Superoxide Dismutase / Q000378:metabolism; D014945:Wound Healing
chemical_list: D000975:Antioxidants; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D010100:Oxygen