ABSTRACT
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 Lungs were removed, and samples were withdrawn for total RNA extraction, cDNA synthesis, and mRNA levels were evaluated by RT-qPCR.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.
Subject(s)
Acute Lung Injury/etiology , Acute Lung Injury/genetics , DNA Repair/genetics , Lasers , Sepsis/complications , Animals , DNA Glycosylases/genetics , DNA Glycosylases/metabolism , 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 , Lipopolysaccharides , Lung/pathology , Lung/radiation effects , Male , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Wistar , Xeroderma Pigmentosum Group D Protein/genetics , Xeroderma Pigmentosum Group D Protein/metabolismABSTRACT
Acute respiratory distress syndrome (ARDS) and acute lung injury (ALI) are defined as pulmonary inflammation that could occur from sepsis and lead to pulmonary permeability and alveolar edema making them life-threatening diseases. Photobiomodulation (PBM) properties have been widely described in the literature in several inflammatory diseases; although the mechanisms of action are not always clear, this could be a possible treatment for ARDS/ALI. Thus, the aim of this study was to evaluate the mRNA levels from caspase-3 and BCL-2 genes and DNA fragmentation in lung tissue from Wistar rats affected by ALI and subjected to photobiomodulation by exposure to a low power infrared laser (808 nm; 100 mW; 3.571 W cm-2; four points per lung). Adult male Wistar rats were randomized into 6 groups (n = 5, for each group): control, PBM10 (10 J cm-2, 2 J and 2 seconds), PBM20 (20 J cm-2, 5 J and 5 seconds), ALI, ALI + PBM10 and ALI + PBM20. ALI was induced by intraperitoneal Escherichia coli lipopolysaccharide injection. Lung samples were collected and divided for mRNA expression of caspase-3 and Bcl-2 and DNA fragmentation quantifications. Data show that caspase-3 mRNA levels are reduced and Bcl-2 mRNA levels increased in ALI after low power infrared laser exposure when compared to the non-exposed ALI group. DNA fragmentation increased in inflammatory infiltrate cells and reduced in alveolar cells. Our research shows that photobiomodulation can alter relative mRNA levels in genes involved in the apoptotic process and DNA fragmentation in inflammatory and alveolar cells after lipopolysaccharide-induced acute lung injury. Also, inflammatory cell apoptosis is part of the photobiomodulation effects induced by exposure to a low power infrared laser.
Subject(s)
Acute Lung Injury/therapy , Caspase 3/genetics , DNA Fragmentation/radiation effects , Genes, bcl-2/radiation effects , Low-Level Light Therapy , Lung/pathology , RNA, Messenger/genetics , Acute Lung Injury/genetics , Acute Lung Injury/pathology , Animals , Apoptosis/radiation effects , Gene Expression Regulation/radiation effects , Infrared Rays/therapeutic use , Lung/metabolism , Lung/radiation effects , Male , Rats, WistarABSTRACT
Os efeitos biológicos promovidos pelo laser de baixa potência resultam em cicatrização mais rápida das feridas. No entanto, as feridas são sistemas muito complexos, tanto do ponto de vista microbiano quanto do hospedeiro. Como a infecção é uma causa comum de cicatrização retardada, é importante entender o efeito da terapia com laser de baixa intensidade no crescimento bacteriano. Esta mini-revisão resume as evidências atuais sobre os efeitos do laser de baixa intensidade em estudos de bactérias in vitro. (AU)
The biological effects promoted by low power laser result in faster wound healing. However, wounds are very complex systems from both host and microbial point of view. Since infection is a common cause of delayed wound healing, it is important to understand the effect of low-level laser therapy in bacterial growth. This mini-review summaries the current evidence about effects of low level laser on bacteria vitro studies. (AU)
