Photobiomodulation with 808-nm diode laser light promotes wound healing of human endothelial cells through increased reactive oxygen species production stimulating mitochondrial oxidative phosphorylation

• Published in: Lasers in medical science Vol. 34; no. 3; pp. 495 - 504
• Main Authors: Amaroli, Andrea, Ravera, Silvia, Baldini, Francesca, Benedicenti, Stefano, Panfoli, Isabella, Vergani, Laura
• Format: Journal Article
• Language: English
• Published: London Springer London 01-04-2019; Springer Nature B.V
• Subjects: Cell proliferation; Dentistry; Electron transport; Endothelial cells; Energy measurement; Free radicals; I.R. radiation; Infrared radiation; Irradiation; Lasers; Light; Light therapy; Medicine; Medicine & Public Health; Metabolism; Mitochondria; Molecular modelling; NF-κB protein; Nitric oxide; Optical Devices; Optics; Original Article; Oxidative phosphorylation; Oxidative stress; Oxygen consumption; Phosphorylation; Photonics; Quantum Optics; Reactive oxygen species; Stimulation; Wavelengths; Wound healing; Mitochondrial respiration; Photobiomodulation (PBM); NIR-diode laser; Human endothelial cells (HECV); Wound regeneration
• ISSN: 0268-8921; 1435-604X
• DOI: 10.1007/s10103-018-2623-5

Photobiomodulation of cells using near-infrared (NIR) monochromatic light can affect cell functions such as proliferation, viability, and metabolism in a range of cell types. Evidence for the effects of near-infrared light on endothelial cells has been reported, but the studies were mainly performed using VIS light emitted by low-energy lasers, because NIR wavelengths seemed negatively stimulate these cells. Cell viability, free radical-induced oxidative stress, NF-κB activation, nitric oxide release, mitochondrial respiration, and wound healing repair were assessed in human endothelial cells (HECV) irradiated with 808-nm diode laser light (laser setup = 1 W/cm
2
, 60 s, 60 J/cm
2
, CW vs measured energy parameter = 0.95 W/cm
2
, 60 s, 57 J/cm
2
, mode CW) emitted by an handpiece with flat-top profile. No difference in viability was detected between controls and HECV cells irradiated with 808-nm diode laser light for 60 s. Irradiated cells demonstrated higher proliferation rate and increased migration ability associated to moderate increase in ROS production without a significant increase in oxidative stress and oxidative stress-activated processes. Near-infrared light stimulated mitochondrial oxygen consumption and ATP synthesis in HECV cells. Short near-infrared irradiation did not affect viability of HECV cells, rather led to a stimulation of wound healing rate, likely sustained by ROS-mediated stimulation of mitochondrial activity. Our results demonstrating that near-infrared led to a shift from anaerobic to aerobic metabolism provide new insight into the possible molecular mechanisms by which photobiomodulation with 808-nm diode laser light protects against inflammation-induced endothelial dysfunction, seemingly promising to enhance their therapeutic properties.