José Carlos Tatmatsu-Rocha1, Carla Roberta Tim2, Lucimar Avo3, Rubens Bernardes-Filho4, Patricia Brassolatti5, Hueliton Wilian Kido6, Michael R Hamblin7, Nivaldo Antonio Parizotto8. 1. Medicine School, Physiotherapy Department, Federal University of Ceara, Fortaleza, Ceara, Brazil. Electronic address: tatmatsu@ufc.br. 2. Brasil University, Postgraduate program in Biomedical Engineering, Brazil. 3. Medicine Department, Federal University of São Carlos, São Paulo, Brazil. 4. Brazilian Enterprise of Agriculture Research, EMBRAPA, São Carlos, SP, Brazil. Electronic address: rubens.bernardes@embrapa.br. 5. Biotechnology Department, Federal University of São Carlos, São Paulo, Brazil. 6. Nove de Julho University (UNINOVE), Bauru, SP, Brazil. 7. Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Dermatology, Harvard Medical School, Boston, MA 02115, USA; Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA 02139, USA. 8. Physiotherapy Department, Federal University of Sao Carlos, Sao Paulo, Brazil.
Abstract
OBJECTIVE: Mitochondrial dysfunction has been associated with the development of diabetes mellitus which is characterized by disorders of collagen production and impaired wound healing. This study analyzed the effects of photobiomodulation (PBM) mediated by laser and light-emitting diode (LED) on the production and organization of collagen fibers in an excisional wound in an animal model of diabetes, and the correlation with inflammation and mitochondrial dynamics. METHODS: Twenty Wistar rats were randomized into 4 groups of 5 animals. Groups: (SHAM) a control non-diabetic wounded group with no treatment; (DC) a diabetic wounded group with no treatment; (DLASER) a diabetic wounded group irradiated by 904 nm pulsed laser (40 mW, 9500 Hz, 1 min, 2.4 J); (DLED) a diabetic wounded group irradiated by continuous wave LED 850 nm (48 mW, 22 s, 1.0 J). Diabetes was induced by injection with streptozotocin (70 mg/kg). PBM was carried out daily for 5 days followed by sacrifice and tissue removal. RESULTS: Collagen fibers in diabetic wounded skin were increased by DLASER but not by DLED. Both groups showed increased blood vessels by atomic force microscopy. Vascular endothelial growth factor (VEGF) was higher and cyclooxygenase (COX2) was lower in the DLED group. Mitochondrial fusion was higher and mitochondrial fusion was lower in DLED compared to DLASER. CONCLUSION: Differences observed between DLASER and DLED may be due to the pulsed laser and CW LED, and to the higher dose of laser. Regulation of mitochondrial homeostasis may be an important mechanism for PBM effects in diabetes.
OBJECTIVE:Mitochondrial dysfunction has been associated with the development of diabetes mellitus which is characterized by disorders of collagen production and impaired wound healing. This study analyzed the effects of photobiomodulation (PBM) mediated by laser and light-emitting diode (LED) on the production and organization of collagen fibers in an excisional wound in an animal model of diabetes, and the correlation with inflammation and mitochondrial dynamics. METHODS: Twenty Wistar rats were randomized into 4 groups of 5 animals. Groups: (SHAM) a control non-diabetic wounded group with no treatment; (DC) a diabetic wounded group with no treatment; (DLASER) a diabetic wounded group irradiated by 904 nm pulsed laser (40 mW, 9500 Hz, 1 min, 2.4 J); (DLED) a diabetic wounded group irradiated by continuous wave LED 850 nm (48 mW, 22 s, 1.0 J). Diabetes was induced by injection with streptozotocin (70 mg/kg). PBM was carried out daily for 5 days followed by sacrifice and tissue removal. RESULTS: Collagen fibers in diabetic wounded skin were increased by DLASER but not by DLED. Both groups showed increased blood vessels by atomic force microscopy. Vascular endothelial growth factor (VEGF) was higher and cyclooxygenase (COX2) was lower in the DLED group. Mitochondrial fusion was higher and mitochondrial fusion was lower in DLED compared to DLASER. CONCLUSION: Differences observed between DLASER and DLED may be due to the pulsed laser and CW LED, and to the higher dose of laser. Regulation of mitochondrial homeostasis may be an important mechanism for PBM effects in diabetes.
Authors: Eva Black; Jette Vibe-Petersen; Lars N Jorgensen; Søren M Madsen; Magnūs S Agren; Per E Holstein; Hans Perrild; Finn Gottrup Journal: Arch Surg Date: 2003-01