Phototherapy promotes healing of cutaneous wounds in undernourished rats

Abstract

BACKGROUNDVarious studies have shown that phototherapy promotes the healing of cutaneous wounds.OBJECTIVETo investigate the effect of phototherapy on healing of cutaneous wounds in nourished and undernourished rats.METHODSForty rats, 20 nourished plus 20 others rendered marasmus with undernourishment, were assigned to four equal groups: nourished sham, nourished Light Emitting Diode treated, undernourished sham and undernourished Light Emitting Diode treated. In the two treated groups, two 8-mm punch wounds made on the dorsum of each rat were irradiated three times per week with 3 J/cm2 sq cm of combined 660 and 890nm light; wounds in the other groups were not irradiated. Wounds were evaluated with digital photography and image analysis, either on day 7 or day 14, with biopsies obtained on day 14 for histological studies.RESULTSUndernourishment retarded the mean healing rate of the undernourished sham wounds (p < 0.01), but not the undernourished Light emission diode treated wounds, which healed significantly faster (p < 0.001) and as fast as the two nourished groups. Histological analysis showed a smaller percentage of collagen in the undernourished sham group compared with the three other groups, thus confirming our photographic image analysis data.CONCLUSIONPhototherapy reverses the adverse healing effects of undernourishment. Similar beneficial effects may be achieved in patients with poor nutritional status.

Evaluation of Tissue Response in Sites Sutured with Cyanoacrylate and Submitted to Low Power Laser Therapy: A Randomized Clinical Trial

“…Most authors in the literature demonstrate that laser therapy accelerates the tissue repair process by increasing cellular metabolism, even in tissues in a poor nutritional state, which induces the production of collagen, angiogenesis, fibroblasts and epithelial tissue. In relation to the laser irradiation protocol, they differ in the activation medium, the energy dose used, as well as the mode and the number of applications [8,11,[19][20][21][22][23].…”

“…This makes it difficult to compare results and subsequently select appropriate treatment parameters. In most cases, the lasers utilized are HeNe, AsGa, GaAlAs and InGaAlP [8,11,19,[23][24][25].…”

Lasertherapy as A Strategy for Treatment Healing under Caloric Restriction – Study in Rats

“…Then, trichotomy was performed on the skin of the dorsum of all animals. For a greater use (refinement) and a reduction on the animal's amount, two excisions were performed on the dorsal region of each rat using a histological punch of 1.5 cm diameter, reaching the dermo-epidermal region until the exposure of the muscular fascia [16,[19][20][21]. These both skin samples obtained were used to investigate the skin changes caused by 30% of CR in the skin before lesion (without treatment), obtaining the groups (n = 6 animals/group): NR (no-restricted-on ad libitum diet) and R (restricted-under 30% of CR).…”

“…The initial area corresponds to the day of the surgical procedure (0 day) and the final area corresponds to the day of euthanasia (2nd, 7th or 14th days, post-injury). WHR values greater than zero represent a decrease in wounded area (reepithelialization) and smaller than zero represent an increase in wounded area [16,20].…”

“…Studies have shown that the photons emitted by the laser are transformed in ATP and used by the cell to power needed metabolic activities, such as cell proliferation, and collagen synthesis. All of them, accelerate the tissue repair in chronic wounds [15,16], especially when associated with oxidative stress status, like nutritional deficit and clinical situations of CR, for example. In this view, it was hypothesized that wounds associated with 30% of CR are healing slowly or not at all, may benefit from lasertherapy.…”