Chong Huang1,2, Sheng Lin Qian2, Li Yue Sun3, Biao Cheng2. 1. 1 The Second Military Medical University of People's Liberation Army , Shang Hai, P.R. China . 2. 2 Department of Plastic Surgery, General Hospital of Guangzhou Military Command , PLA, Guangzhou, P.R. China . 3. 3 Department of Oncology, General Hospital of Guangzhou Military Command , PLA, Guangzhou, P.R. China .
Abstract
OBJECTIVE: The objective of this study was to determine the effect of light-emitting diode (LED) irradiation on the migration and proliferation of keratinocytes. BACKGROUND DATA: Keratinocytes play a key role in re-epithelialization during wound healing; it is speculated that low-level LED therapy might improve keratinocyte migration and proliferation. MATERIALS AND METHODS: Human keratinocyte cells (HKCs) were isolated from child or adult foreskins and irradiated with LED light with a wavelength of 640 nm and a dosage of 12 or 24 J/cm(2). Cell motility, migration, and proliferation were examined using live cell imaging, scratch assay, and a colorimetric cell counting assay, respectively. Hypoxia-inducible factor-1α (HIF-1α) protein levels were analyzed by using Western blotting. Filamentous actin (F-actin) was stained by phalloidin. YC-1 [3-(5-hydroxymethyl-2-furyl)-1-benzylindazole] was used as an HIF-1 inhibitor, and CoCl2 (cobalt chloride) and DMOG (dimethyloxaloyl glycine) are HIF-1α activators. RESULTS: LED irradiation significantly promoted cell motility and migration, but did not significantly influence cell proliferation in HKCs. Furthermore, LED irradiation resulted in a reorganization of cellular F-actin and a dramatic upregulation of HIF-1α expression. Suppression of HIF-1α using the compound YC-1 prevented reorganization of the actin cytoskeleton following LED irradiation, suggesting that the effect of LED irradiation on the cytoskeleton is mediated through HIF-1α. Conversely, chemical activation of HIF-1α via DMOG or CoCl2 resulted in a reorganization of F-actin. CONCLUSIONS: LED irradiation may increase keratinocyte migration via HIF-1α-dependent cytoskeletal reorganization.
OBJECTIVE: The objective of this study was to determine the effect of light-emitting diode (LED) irradiation on the migration and proliferation of keratinocytes. BACKGROUND DATA: Keratinocytes play a key role in re-epithelialization during wound healing; it is speculated that low-level LED therapy might improve keratinocyte migration and proliferation. MATERIALS AND METHODS:Human keratinocyte cells (HKCs) were isolated from child or adult foreskins and irradiated with LED light with a wavelength of 640 nm and a dosage of 12 or 24 J/cm(2). Cell motility, migration, and proliferation were examined using live cell imaging, scratch assay, and a colorimetric cell counting assay, respectively. Hypoxia-inducible factor-1α (HIF-1α) protein levels were analyzed by using Western blotting. Filamentous actin (F-actin) was stained by phalloidin. YC-1 [3-(5-hydroxymethyl-2-furyl)-1-benzylindazole] was used as an HIF-1 inhibitor, and CoCl2 (cobalt chloride) and DMOG (dimethyloxaloyl glycine) are HIF-1α activators. RESULTS: LED irradiation significantly promoted cell motility and migration, but did not significantly influence cell proliferation in HKCs. Furthermore, LED irradiation resulted in a reorganization of cellular F-actin and a dramatic upregulation of HIF-1α expression. Suppression of HIF-1α using the compound YC-1 prevented reorganization of the actin cytoskeleton following LED irradiation, suggesting that the effect of LED irradiation on the cytoskeleton is mediated through HIF-1α. Conversely, chemical activation of HIF-1α via DMOG or CoCl2 resulted in a reorganization of F-actin. CONCLUSIONS: LED irradiation may increase keratinocyte migration via HIF-1α-dependent cytoskeletal reorganization.
Authors: Ann Liebert; Brian Bicknell; Daniel M Johnstone; Luke C Gordon; Hosen Kiat; Michael R Hamblin Journal: Photobiomodul Photomed Laser Surg Date: 2019-10-09