Effect of laser and LED phototherapies on the healing of cutaneous wound on healthy and iron-deficient Wistar rats and their impact on fibroblastic activity during wound healing

Abstract

Iron deficiency impairs the formation of hemoglobin, red blood cells, as well the transport of oxygen. The wound healing process involves numerous functions, many of which are dependent on the presence of oxygen. Laser has been shown to improve angiogenesis, increases blood supply, cell proliferation and function. We aimed to study the effect of λ660 nm laser and λ700 nm light-emitting diode (LED) on fibroblastic proliferation on cutaneous wounds on iron-deficient rodents. Induction of iron anemia was carried out by feeding 105 newborn rats with a special iron-free diet. A 1 × 1 cm wound was created on the dorsum of each animal that were randomly distributed into seven groups: I, control anemic; II, anemic no treatment; III, anemic+L; IV, anemic+LED; V, healthy no treatment; VI, healthy+laser; VII, healthy+LED (n=15 each). Phototherapy was carried out using either a diode laser (λ660 nm, 40 mW, 10 J/cm(2)) or a prototype LED device (λ700 ± 20 nm, 15 mW, 10 J/cm(2)). Treatment started immediately after surgery and was repeated at 48-h interval during 7, 14, and 21 days. After animal death, specimens were taken, routinely processed, cut, stained with hematoxylin-eosin, and underwent histological analysis and fibroblast counting. Significant difference between healthy and anemic subjects on regards the number of fibroblast between treatments was seen (p<0.008, p<0.001). On healthy animals, significant higher count was seen when laser was used (p<0.008). Anemic subjects irradiated with LED showed significantly higher count (p<0.001). It is concluded that the use of LED light caused a significant positive biomodulation of fibroblastic proliferation on anemic animals and laser was more effective on increasing proliferation on non-anemics.

The relative antimicrobial effect of blue 405 nm LED and blue 405 nm laser on methicillin-resistant Staphylococcus aureus in vitro

“…The low cost of LEDs compared to lasers, and their ubiquity, suggests that LED-based devices will remain preferred by many over lasers, unless there is strong evidence that intervention with lasers yield superior results. Consequently, the photobiomodulative effect of LEDs relative to lasers has been questioned by many [1,2], with some asserting that laser diodes are more effective than LEDs [3,4] and others claiming that LEDs are as effective as lasers [1,[4][5][6][7][8].…”

Comparação do laser e do led no processo de cicatrização em feridas cutâneas: uma revisão

“…Dois estudos 17,19 compararam a eficácia do LASER e do LED em modelos animais de doenças consideradas de risco para dificuldades de cicatrização cutânea (diabetes e deficiência de ferro, respectivamente). Dois estudos realizaram a pesquisa em animais saudáveis 18,20 e uma pesquisa avaliou os efeitos da fototerapia em um modelo animal de queimadura 21 .…”

“…Dois estudos realizaram a pesquisa em animais saudáveis 18,20 e uma pesquisa avaliou os efeitos da fototerapia em um modelo animal de queimadura 21 . Em relação aos parâmetros fototerapêuticos escolhidos, três estudos 17,19,20 utilizaram LASERs e LEDs com comprimentos de onda vermelhos (λ < 700 nm). De Souza et al 18 e Catão et al 21 aplicaram ambos os espectros vermelhos e infra-vermelhos nos grupos analisados.…”

“…Oliveira Sampaio et al 19 [27][28][29] e o LED 15,16,25 nas faixas espectrais vermelha e infra-vermelha podem aumentar a vasodilatação e a microcirculação local, resultando no aumento do aporte de oxigênio e nutrientes na lesão cutânea. Além disso, também se observou que o LED no comprimento de onda verde foi capaz de estimular a angiogênese significativamente.…”

Magnetoledtherapy in the treatment of wounds after surgical procedures of the knee joint

“…The obtained results have been confirmed in the studies done by Chaves et al and Borg et al14,15 The beneficial effect of applying magnetic fields and low-energy light in wound treatment results from their biological effects, among which one can enumerate the intensification of oxygen utilization processes and tissue respiration, increased intensity of anaerobic respiration, processes in ischemic tissues, and vasodilatation and angiogenic activities, which cause the development of collateral circulation in the area where the wound forms 13,16. In addition, those factors intensify regeneration processes (the stimulation of DNA replication processes, as well as synthesis of proteins and collagen) and repair, stimulating the epidermization process (acceleration of mitosis in cells of the germinative layer of epidermis) and inhibiting infection processes 17,18. The mechanism of therapeutic action of magnetic fields in such cases consists of stimulation of the regeneration of a destroyed network of vessels responsible for microcirculation, as well as enhancing of local blood supply for tissues.…”