Low-power laser alters mRNA levels from DNA repair genes in acute lung injury induced by sepsis in Wistar rats

Lasers Med Sci. 2019 Feb;34(1):157-168. doi: 10.1007/s10103-018-2656-9. Epub 2018 Oct 8.


Acute lung injury (ALI) is defined as respiratory failure syndrome, in which the pathogenesis could occur from sepsis making it a life-threatening disease by uncontrolled hyperinflammatory responses. A possible treatment for ALI is the use of low-power infrared lasers (LPIL), whose therapeutical effects depend on wavelength, power, fluence, and emission mode. The evaluation mRNA levels of repair gene related to oxidative damage after exposure to LPIL could provide important information about the modulation of genes as treatment for ALI. Thus, the aim of this study was to evaluate the mRNA levels from OGG1, APEX1, ERCC2, and ERCC1 genes in lung tissue from Wistar rats affected by ALI and after exposure to LPIL (808 nm; 100 mW). Adult male Wistar rats (n = 30) were randomized into six groups (n = 5, for each group): control, 10 J/cm2 (2 J), 20 J/cm2 (5 J), ALI, ALI + LPIL 10 J/cm2 and ALI + LPIL 20 J/cm2. ALI was induced by intraperitoneal E. coli lipopolysaccharide injection (10 mg/kg). Lungs were removed, and samples were withdrawn for total RNA extraction, cDNA synthesis, and mRNA levels were evaluated by RT-qPCR. Data normality was verified by Kolmogorov-Smirnov, comparisons among groups were by Student's t test, Mann-Whitney test, one-way ANOVA, Kruskal-Wallis followed by post-tests. Data showed that OGG1 (0.39 ± 0.10), ERCC2 (0.67 ± 0.24), and ERCC1 (0.60 ± 0.19) mRNA levels are reduced in ALI group when compared with the control group (1.00 ± 0.07, 1.03 ± 0.25, 1.01 ± 0.16, respectively) and, after LPIL, mRNA relative levels from DNA repair genes are altered when compared to non-exposed ALI group. Our research shows that ALI alter mRNA levels from genes related to base and nucleotide excision repair genes, suggesting that DNA repair is part of cell response to sepsis, and that photobiomodulation could modulate the mRNA levels from these genes in lung tissue.

Keywords: Acute lung injury; DNA repair; Low-power laser; Sepsis; Wistar rats.

MeSH terms

  • Acute Lung Injury / etiology*
  • Acute Lung Injury / genetics*
  • Animals
  • DNA Glycosylases / genetics
  • DNA Glycosylases / metabolism
  • DNA Repair / genetics*
  • DNA Repair / radiation effects
  • DNA Repair Enzymes / genetics
  • DNA Repair Enzymes / metabolism
  • DNA-(Apurinic or Apyrimidinic Site) Lyase / genetics
  • DNA-(Apurinic or Apyrimidinic Site) Lyase / metabolism
  • Escherichia coli
  • Gene Expression Regulation / radiation effects
  • Lasers*
  • Lipopolysaccharides
  • Lung / pathology
  • Lung / radiation effects
  • Male
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Rats
  • Rats, Wistar
  • Sepsis / complications*
  • Xeroderma Pigmentosum Group D Protein / genetics
  • Xeroderma Pigmentosum Group D Protein / metabolism


  • Lipopolysaccharides
  • RNA, Messenger
  • DNA Glycosylases
  • OGG1 protein, rat
  • Xeroderma Pigmentosum Group D Protein
  • Apex1 protein, rat
  • DNA-(Apurinic or Apyrimidinic Site) Lyase
  • DNA Repair Enzymes
  • ERCC1 protein, rat