Effect of LED phototherapy (λ700 ± 20 nm) on TGF-ß expression during wound healing: an immunohistochemical study in a rodent model.

OBJECTIVE: The aim of the present investigation was to evaluate transforming growth factor ß (TGF-ß) expression on cutaneous wounds in rodents treated or not treated with LED light. BACKGROUND: TGF-ß is a multifunctional cytokine that presents a central action during tissue repair. Although several studies both in vitro and in vivo have shown that LED phototherapy influences tissue repair, a full understanding of the mechanisms involved in its usage, such as in the modulation of some growth factors, remains unclear. MATERIALS AND METHODS: Under general anesthesia, 24 young adult male Wistar rats weighing 200-250 g had one excisional wound created on the dorsum of each, and were randomly distributed into two groups: G0 (Control) and G1 (LED, λ700 ± 20 nm, 16 mW, SAEF = 5 J/cm(2), Illuminated Area = 2 cm(2), 8 mWcm(2), 626 s) Each group was subdivided into three subgroups according to the animal death timing (2, 4, and 6 days). LED phototherapy started immediately after surgery and was repeated every other day during the experimental time. Following animal death, specimens were removed, routinely processed to wax, cut and immunomarked with polyclonal anti-TGF-ß, and underwent histological analysis by light microscopy. The mean area of expression of each group was calculated. The data were statistically analyzed using ANOVA and Tukey's test. RESULTS: The area of the expression of TGF-ß on LED-irradiated animals was significantly smaller than on controls at day 2 (p = 0.013). No significant difference was found at later times. It is concluded that the use of LED light, at these specific parameters, caused an inhibition of the expression of TGF-ß at an early stage of the healing process.

Polarized light (λ400-2000 nm) on third-degree burns in diabetic rats: immunohistochemical study.

AIM: The aim of this study was to evaluate with light microscopy the healing process of third-degree burns on diabetic rats treated with polarized light (λ400-2000 nm, 20 or 40 J/cm(2)/session, 40 mW/cm(2), 2.4 J/cm(2)/min, 5.5-cm beam diameter). BACKGROUND: Uncontrolled diabetes mellitus causes severe disruption of the body's metabolism, including healing. Polarized light sources have been shown to be effective in improving healing in many situations. ANIMALS AND METHODS: Diabetes mellitus was induced with streptozotocin (60 mg/kg) in 45 male Wistar albino rats, and a third-degree burn (1.5 by 1.5 cm) was created on the dorsum of each animal under general anesthesia. The animals were randomly distributed into three groups: control, 20 J/cm(2), and 40 J/cm(2). Each group was then divided into three subgroups based on time of death (7, 14, 21 d). Phototherapy (20 or 40 J/cm(2) per session) was carried out immediately after the burning and repeated daily until the day before death. Following animal death, specimens were removed, embedded in paraffin, sectioned, and stained with hematoxylin and eosin (HE) or Sirius Red or immunomarked with CK AE1/AE3 antibody. Qualitative and semiquantitative analyses were performed under light microscopy. The results were statistically analyzed. RESULTS: The animals treated with 20 J/cm(2) showed significant differences with regard to revascularization and re-epithelialization. Although the 40 J/cm(2) group showed stimulation of fibroblastic proliferation as an isolated feature, no other difference from the control was observed. CONCLUSION: Our results suggest that the use of polarized light at 20 J/cm(2) effectively improves the healing of third-degree burns on diabetic animals at both early and late stages of repair.

Laser light may improve the symptoms of oral lesions of cicatricial pemphigoid: a case report.

OBJECTIVE: The aim of this work is to report the handling of a patient suffering from cicatricial pemphigoid (CP) treated with laser phototherapy (LPT) and systemic steroids. BACKGROUND DATA: CP is a group of rare chronic autoimmune blistering diseases that predominately affect the mucous membranes and occasionally the skin. The gingiva is most commonly involved, followed by the palate and the buccal mucosa. High-dosage systemic steroids are widely used for its treatment. LPT has been shown to improve wound healing and relieve pain. Its efficacy depends on the amount of energy delivered to the tissue, exposure time, and delivery method. MATERIALS AND METHODS: A white 47-y-old man with CP who used systemic steroids for the previous 5 y was examined at our clinic. Extra- and intraoral examination revealed classic signs of the condition. LPT (GaAlAs diode laser, 660 nm wavelength, 30 mW, continuous wave, diameter approximately 3 mm, 60 J/cm(2) per session) was used in association with the steroids. LPT was performed in a punctual contact manner every other day on the oral mucosa. Maintenance of the treatment was carried out weekly because interruption of the LPT resulted in the recurrence of the lesions. At the time that this report was written, the patient had been undergoing twice weekly treatments for 6 months without signs of lesion recurrence. CONCLUSION: Concomitant use of systemic steroids and LPT showed a positive effect on controlling oral CP lesions and on improving both oral health and the quality of life of the patient.