The influence of low-level laser therapy on parameters of oxidative stress and DNA damage on muscle and plasma in rats with heart failure

Abstract

In heart failure (HF), there is an imbalance between the production of reactive oxygen species and the synthesis of antioxidant enzymes, causing damage to the cardiovascular function and increased susceptibility to DNA damage. The aim of this study was to evaluate the influence of low-level laser therapy (LLLT) on parameters of oxidative stress and DNA damage in skeletal muscle and plasma of rats with HF. Wistar rats were allocated into six groups: "placebo" HF rats (P-HF, n = 9), "placebo" Sham rats (P-sham, n = 8), HF rats at a dose 3 J/cm(2) of LLLT (3 J/cm(2)-HF, n = 8), sham rats at a dose 3 J/cm(2) of LLLT (3 J/cm(2)-sham, n = 8), HF rats at a dose 21 J/cm(2) of LLLT (21 J/cm(2)-HF, n = 8) and sham rats at a dose 21 J/cm(2) of LLLT (21 J/cm(2)-sham, n = 8). Animals were submitted to a LLLT protocol for 10 days at the right gastrocnemius muscle. Comparison between groups showed a significant reduction in superoxide dismutase (SOD) activity in the 3 J/cm(2)-HF group (p = 0.03) and the 21 J/cm(2)-HF group (p = 0.01) compared to the P-HF group. 2',7'-Dihydrodichlorofluorescein (DCFH) oxidation levels showed a decrease when comparing 3 J/cm(2)-sham to P-sham (p = 0.02). The DNA damage index had a significant increase either in 21 J/cm(2)-HF or 21 J/cm(2)-sham in comparison to P-HF (p = 0.004) and P-sham (p = 0.001) and to 3 J/cm(2)-HF (p = 0.007) and 3 J/cm(2)-sham (p = 0.037), respectively. Based on this, laser therapy appears to reduce SOD activity and DCFH oxidation levels, changing the oxidative balance in the skeletal muscle of HF rats. Otherwise, high doses of LLLT seem to increase DNA damage.

Low level laser therapy reduces acute lung inflammation without impairing lung function

“…There are evidences suggesting that LLLT may act on the mitochondria , increasing adenosine tri‐phosphate (ATP) production . LLLT was also implicated on the activation of transcription factors , and in modulating the intracellular redox balance . Actually, it seems probable that laser intracellular targets may vary from one tissue to other, depending on the cellular types and the characteristics of the light.…”

Functional capacity in a rat model of heart failure: impact of myocardial infarct size

“…; Biasibetti et al . ). Sham‐operated control rats underwent the same procedures, without ligation of the coronary artery, and served as control rats.…”

“…First, animals were weighed, anaesthetized with xylazine (12 mg kg −1 , I.P., Bayer, São Paulo, SP, Brazil) and ketamine (90 mg kg −1 , I.P., Vetaset, Pfizer, Campinas, SP, Brazil), intubated, and artificially ventilated (SamWay VR 15, Montevideo, Uruguay) with a breathing rate of 60 breaths min −1 and an inspired fraction of oxygen of 100%. The rat model of HF was induced by myocardial infarction following coronary artery ligation, as previously described in other studies from our laboratory (Nunes et al 2008;Jaenisch et al 2011;Hentschke et al 2013;Alves et al 2014;Biasibetti et al 2014). Sham-operated control rats underwent the same procedures, without ligation of the coronary artery, and served as control rats.…”

“…In order to complement the echocardiographic analysis, we also performed invasive haemodynamic evaluation, widely used in our laboratory (Nunes et al 2008;Jaenisch et al 2011;Hentschke et al 2013Hentschke et al , 2017Alves et al 2014;Biasibetti et al 2014).…”

Analysis of Radiomodulatory Effect of Low-Level Laser Irradiation by Clonogenic Survival Assay

“…Former research has shown that LLLI at higher energy densities enhanced DNA damage compared with unirradiated cells. 46,47 Based on the ''law of Bergonié and Tribondeau'' in radiobiology, radiosensitivity of cells helps to increase the level of metabolic activity and the proliferation rate. A significant increase of plating efficiency in HeLa cells represents cell proliferation caused by LLLI.…”