title: Low-level laser therapy decreases renal interstitial fibrosis.
abstract: OBJECTIVE
  the purpose of this study was to investigate the effect of low-level laser therapy (LLLT) on chronic kidney disease (CKD) in a model of unilateral ureteral obstruction (UUO).
  
  
  BACKGROUND
  Regardless of the etiology, CKD involves progressive widespread tissue fibrosis, tubular atrophy, and loss of kidney function. This process also occurs in kidney allograft. At present, effective therapies for this condition are lacking. We investigated the effects of LLLT on the interstitial fibrosis that occurs after experimental UUO in rats.
  
  
  METHODS
  The occluded kidney of half of the 32 Wistar rats that underwent UUO received a single intraoperative dose of LLLT (AlGaAs laser, 780 nm, 22.5 J/cm(2), 30 mW, 0.75 W/cm(2), 30 sec on each of nine points). After 14 days, renal fibrosis was assessed by Sirius red staining under polarized light. Immunohistochemical analyses quantitated the renal tissue cells that expressed fibroblast (FSP-1) and myofibroblast (α-SMA) markers. Reverse transcriptase polymerase chain reaction (RT-PCR) was performed to determine the mRNA expression of interleukin (IL)-6, monocyte chemotactic protein-1 (MCP-1), transforming growth factor (TGF)-β1 and Smad3.
  
  
  RESULTS
  The UUO and LLLT animals had less fibrosis than the UUO animals, as well having decreased expression inflammatory and pro-fibrotic markers.
  
  
  CONCLUSIONS
  For the first time, we showed that LLLT had a protective effect regarding renal interstitial fibrosis. It is conceivable that by attenuating inflammation, LLLT can prevent tubular activation and transdifferentiation, which are the two processes that mainly drive the renal fibrosis of the UUO model.
authors.affiliation: Division of Nephrology, Federal University of Juiz de Fora, Juiz de Fora (UFJF), Brazil.
authors.forename: Fabiana Aparecida Mayrink
authors.initials: FA
authors.lastname: Oliveira
authors.forename: Ana Carolina Meneghin
authors.initials: AC
authors.lastname: Moraes
authors.forename: Amanda Povoa
authors.initials: AP
authors.lastname: Paiva
authors.forename: Vânia
authors.initials: V
authors.lastname: Schinzel
authors.forename: Matheus
authors.initials: M
authors.lastname: Correa-Costa
authors.forename: Patricia
authors.initials: P
authors.lastname: Semedo
authors.forename: Angêla
authors.initials: A
authors.lastname: Castoldi
authors.forename: Marcos Antonio
authors.initials: MA
authors.lastname: Cenedeze
authors.forename: Roberto Sotto-Maior Fortes
authors.initials: RS
authors.lastname: Oliveira
authors.forename: Marcus Gomes
authors.initials: MG
authors.lastname: Bastos
authors.forename: Niels Olsen Saraiva
authors.initials: NO
authors.lastname: Câmara
authors.forename: Helady
authors.initials: H
authors.lastname: Sanders-Pinheiro
mesh_terms: D000818:Animals; D001707:Biopsy, Needle; D004195:Disease Models, Animal; D007150:Immunohistochemistry; D007674:Kidney Diseases / Q000473:pathology / Q000532:radiotherapy; D028022:Low-Level Light Therapy / Q000379:methods*; D008297:Male; D009395:Nephritis, Interstitial / Q000473:pathology* / Q000532:radiotherapy*; D051381:Rats; D017208:Rats, Wistar; D012680:Sensitivity and Specificity; D016896:Treatment Outcome