Low-level laser therapy (904nm) can increase collagen and reduce oxidative and nitrosative stress in diabetic wounded mouse skin

Abstract

Background and Objective Over the last decade we have seen an increased interest in the use of Low-Level Laser Therapy (LLLT) in diseases that involve increased oxidative stress. It is well established that hyperglycemia in diabetes elicits a rise in reactive oxygen species (ROS) production but the effect of LLLT remains unclear. This study aimed to investigate whether LLLT was able to improve oxidative/nitrosative stress parameters in the wound healing process in diabetic mice. Study Design/Materials and Methods Twenty male mice were divided into four groups: non-irradiated control (NIC), irradiated control (IC), non-irradiated and diabetic (NID), irradiated and diabetic (ID). Diabetes was induced by administration of streptozotocin. Wounds were created 120 days after the induction of diabetes in groups IC and ID and these groups were irradiated daily for 5 days (superpulsed 904 nm laser, average power 40 mW, 60 sec). All animals were sacrificed 1 day after the last irradiation and histology, collagen amount, catalase activity, nitrite and thiobarbituric acid reactive substances (TBARS) were measured. Results Histology showed that collagen fibers were more organized in IC and ID when compared to NID group, and significant differences in collagen content were found in group ID versus NID. Catalase activity was higher in IC group compared to other groups (p < 0.001). TBARS levels were higher in IC versus NIC, but were lower in ID versus NID (p < 0.001). Nitrite was lower in both irradiated groups versus the respective non-irradiated groups (p < 0.001). Conclusions Delayed wound healing in diabetes is still a challenge in clinical practice with high social costs. The increased production of collagen and decreased oxidative and nitrosative stress suggests that LLLT may be a viable therapeutic alternative in diabetic wound healing.

Photobiomodulation for traumatic brain injury and stroke

“…The changes in expression levels of proteins involved in antioxidant and redox‐regulation, anti‐apoptotic and pro‐survival, cellular proliferation, etc., means that distinct changes in tissue homeostasis, healing, and regeneration can be expected after PBM. For instance, structural proteins such as collagen are newly synthesized in order to repair tissue damage (Tatmatsu‐Rocha et al, ). Cells at risk of dying in tissue that has been subjected to ischemic, or other insults, are protected (Sussai et al, ).…”

The photobiomodulation (658, 830 and 904nm) on wound healing in histomorphometric analysis

“…In fact, we analyzed the samples on the 14-2021876820 th day after the operative procedure, at which time the collagen type I deposition was not yet observed [37]. Furthermore, a better organization of the collagen fibers implies a better cicatricial process [38]. Gupta et al [24] analyzed the effect of the 904 nm laser on the collagen deposition after burn in animal model and observed an increase in the amount of collagen seven days after the injury.…”

“…Gupta et al [24] analyzed the effect of the 904 nm laser on the collagen deposition after burn in animal model and observed an increase in the amount of collagen seven days after the injury. Tamatsu-Rocha et al [38] observed that 904 nm laser radiation promotes a larger and more organized deposition of collagen in healthy or diabetic animals five days after skin lesion. These results support our research, since the animals treated with 904 nm laser had a significant increase of collagen in relation to the laser 830 nm and to the control group.…”

Anti-inflammatory effects of low-level laser in burn wound models in rats

“…The action of low intensity laser therapy is based on the light absorption in thermally injured skin tissue, which will generate proliferation in cellular metabolism [26,29]. LLLT has been shown to accelerate the acute inflammatory process and tissue repair of the wound [30,31].…”