Low‐Level Laser Therapy Restores the Oxidative Stress Balance in Acute Lung Injury Induced by Gut Ischemia and Reperfusion

Abstract

It remains unknown if the oxidative stress can be regulated by low-level laser therapy (LLLT) in lung inflammation induced by intestinal reperfusion (i-I/R). A study was developed in which rats were irradiated (660 nm, 30 mW, 5.4 J) on the skin over the bronchus and euthanized 2 h after the initial of intestinal reperfusion. Lung edema and bronchoalveolar lavage fluid neutrophils were measured by the Evans blue extravasation and myeloperoxidase (MPO) activity respectively. Lung histology was used for analyzing the injury score. Reactive oxygen species (ROS) was measured by fluorescence. Both expression intercellular adhesion molecule 1 (ICAM-1) and peroxisome proliferator-activated receptor-y (PPARy) were measured by RT-PCR. The lung immunohistochemical localization of ICAM-1 was visualized as a brown stain. Both lung HSP70 and glutathione protein were evaluated by ELISA. LLLT reduced neatly the edema, neutrophils influx, MPO activity and ICAM-1 mRNA expression. LLLT also reduced the ROS formation and oppositely increased GSH concentration in lung from i-I/R groups. Both HSP70 and PPARy expression also were elevated after laser irradiation. Results indicate that laser effect in attenuating the acute lung inflammation is driven to restore the balance between the pro- and antioxidants mediators rising of PPARy expression and consequently the HSP70 production.

Therapeutic effects of Laser and L-carnitine against amiodarone-induced pulmonary toxicity in adult male rats

“…The anti-oxidant effect of LC is thought to be due its ability to increase the activity of antioxidant enzymes [20,21]. Laser therapy restores the balance between oxidants and antioxidants [22]. This is in agreement with the laser-induced significant increases in antioxidant parameters seen in the present study.…”

Effect of the transdermal low-level laser therapy on endothelial function

“…The de Lim et al study carried out on rats could be an example. After the low-level laser irradiating, an increased level of reduced glutathione was observed (wavelength λ = 660 nm, power 30 mW, energy 5.4 J), which suggests antioxidant properties of the irradiation [12]. The results of this study prove the effect of LLLT on the GSH levels in human, which was previously observed only in animal models.…”

Preliminary evaluation of the effects of photobiomodulation therapy and physical rehabilitation on early postoperative recovery of dogs undergoing hemilaminectomy for treatment of thoracolumbar intervertebral disk disease

“…19,21,22 This photodissociation would allow oxygen fixation and thereby enhance cellular respiration and metabolism. This type of treatment has been shown to reduce production of factors associated with oxidative stress in various cell types in vitro as well as in affected tissues of laboratory animals with experimentally induced ischemiareperfusion injury or age-related retinal changes 21,[23][24][25][26] and to protect against oxidative stress by activating scavenging superoxide anions. 27 In rats with blunt-impact muscle trauma, photobiomodulation therapy blocked reactive oxygen species release and activation of nuclear factor-kB, inhibited overexpression of inducible nitric oxide synthase, reduced the inflammatory response, and decreased collagen production in the traumatized muscle, compared with traumatized muscles from rats that did not undergo photobiomodulation therapy.…”