title: Photobiomodulation improves cutaneous wound healing in an animal model of type II diabetes.
abstract: OBJECTIVE
  We investigated the effects of photobiomodulation (PBM) on cutaneous wound healing in an animal model of type II diabetes, Psammomys obesus (Sand Rats).
  
  
  BACKGROUND
  632-nm light has been established as the most effective wavelength for treatment of cutaneous wounds; however, the inconsistent efficacy of PBM may be due to inadequate treatment parameter selection.
  
  
  METHODS
  Using 632-nm light, an initial series of experiments were done to establish optimal treatment parameters for this model. Following creation of bilateral full-thickness skin wounds, non-diabetic Sand Rats were treated with PBM of differing dosages. Wound healing was assessed according to wound closure and histological characteristics of healing. Optimal treatment parameters were then used to treat type II diabetic Sand Rats while a diabetic control group received no irradiation. In order to elucidate the mechanism behind an improvement in wound healing, expression of basic fibroblast growth factor (bFGF) was assessed.
  
  
  RESULTS
  Significant improvement in wound healing histology and wound closure were found following treatment with 4 J/cm(2) (16 mW, 250-sec treatments for 4 consecutive days; p < 0.05). The 4 J/cm(2) dosage significantly improved histology and closure of wounds in the diabetic group in comparison to the non-irradiated diabetic group. Quantitative analysis of bFGF expression at 36 h post-injury revealed a threefold increase in the diabetic and non-diabetic Sand Rats after PBM.
  
  
  CONCLUSIONS
  The results demonstrate that PBM at an energy density of 4 J/cm(2) is effective in improving the healing of cutaneous wounds in an animal model of type II diabetes, suggesting that PBM (632 nm, 4 J/cm(2)) would be effective in treating chronic cutaneous wounds in diabetic patients.
authors.affiliation: Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA. krb27@georgetown.edu
authors.forename: Kimberly R
authors.initials: KR
authors.lastname: Byrnes
authors.forename: Lauren
authors.initials: L
authors.lastname: Barna
authors.forename: V Michelle
authors.initials: VM
authors.lastname: Chenault
authors.forename: Ronald W
authors.initials: RW
authors.lastname: Waynant
authors.forename: Ilko K
authors.initials: IK
authors.lastname: Ilev
authors.forename: Leonardo
authors.initials: L
authors.lastname: Longo
authors.forename: Clelia
authors.initials: C
authors.lastname: Miracco
authors.forename: Bryan
authors.initials: B
authors.lastname: Johnson
authors.forename: Juanita J
authors.initials: JJ
authors.lastname: Anders
mesh_terms: D000818:Animals; D001707:Biopsy, Needle; D003921:Diabetes Mellitus, Experimental; D003924:Diabetes Mellitus, Type 2 / Q000532:radiotherapy*; D004195:Disease Models, Animal; D005260:Female; D016222:Fibroblast Growth Factor 2 / Q000032:analysis; D005849:Gerbillinae; D007150:Immunohistochemistry; D028022:Low-Level Light Therapy / Q000379:methods*; D008297:Male; D011897:Random Allocation; D051381:Rats; D012016:Reference Values; D012680:Sensitivity and Specificity; D012867:Skin / Q000473:pathology / Q000528:radiation effects; D014945:Wound Healing / Q000502:physiology / Q000528:radiation effects*; D014947:Wounds and Injuries / Q000473:pathology / Q000532:radiotherapy*
chemical_list: D016222:Fibroblast Growth Factor 2