Journal of Photochemistry and Photobiology (Jun 2021)
Photobiomodulation effects of pulsed-NIR laser (810 nm) and LED (808 ± 3 nm) with identical treatment regimen on burn wound healing: A quantitative label-free global proteomic approach
Abstract
Photobiomodulation (PBM) has evolved as a rapidly growing therapeutic biophysical non-invasive approach for the acceleration of tissue repair, mitigation of pain, inflammation and restoration of cellular functions. This study compares the PBM effect of pulsed-mode (10 Hz) of NIR laser (810 nm) and LED (808 ± 3 nm) with identical treatment regimen (average power 70 mW; average irradiance 40 mW/cm2; total fluence 24 J/cm2, duty cycle 50%; pulse duration 50 msec; peak irradiance 80 mW/cm2; 10 min exposure once daily for 7 days) on full-thickness, third-degree burn wound in rat using comprehensive analysis of quantitative label-free global proteomics, followed by validation of the proteomics data by various biophysical, biochemical, molecular, histological and immunohistochemical (IHC) assays. The proteomic analysis clearly revealed the common biological processes indicated by modulation of similar biological pathways (known for tissue repair process) associated with neuronal (4), metabolic (10), vascular (3), inflammation (4) and cell signaling (12) in both laser and LED treated groups. Validation of proteomic analysis using various healing markers demonstrated attenuated inflammatory response like decreased TNF-α, IL-1β, IL-6, COX-2 levels (ELISA), enhanced cellular proliferation (PCNA, TGF-β2), collagen, ECM accumulation (biochemical, H&E, Masson's trichrome staining, IHC assays), wound contraction and cytoprotection (TUNEL assay) in both laser and LED-treated groups as compared to the control. Collectively, the proteomics data revealed previously know molecules along with novel identified molecules post-PBM treatment, which broaden the understanding of tissue repair mechanisms. This study profoundly signifies that both laser and LED in 810 nm wavelength range at pulsed-mode (10 Hz) are equally effective for PBM-mediated potential treatment to accelerate burn wound healing.
