Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Jan-Feb;100(1):54-62.
doi: 10.1016/j.abd.2024.02.008. Epub 2024 Nov 8.

Red light-emitting diode on skin healing: an in vitro and in vivo experimental study

Tuany R Schmidt  1 , Belkiss C Mármora  1 , Fernanda T Brochado  1 , Lucas Gonçalves  2 , Paloma S Campos  1 , Marcelo L Lamers  1 , Aurigena A de Araújo  3 , Caroline A C X de Medeiros  4 , Susana B Ribeiro  5 , Marco A T Martins  6 , Emily F S Pilar  7 , Manoela D Martins  8 , Vivian P Wagner  9
Affiliations

Red light-emitting diode on skin healing: an in vitro and in vivo experimental study

Tuany R Schmidt et al. An Bras Dermatol. 2025 Jan-Feb.

Abstract

Background: The clinical advantages of light-emitting diode (LED) therapy in skin healing and its underlying mechanism remain subjects of ongoing debate.

Objective: This study aims to explore the impact of LED therapy on normal skin keratinocytes (HaCaT) and in the repair of full-thickness dorsal wounds in Wistar rats.

Methods: HaCaT cell viability (SRB assay) and migration (scratch assay) were assessed under LED therapy, comparing stress conditions (2.5% FBS) with sham irradiation and optimal conditions (10% FBS). In vivo, 50 rats with induced wounds were divided into Sham and LED (daily treatment) groups. Euthanasia occurred at 3, 5, 10, 14, and 21 days for clinical, morphological, oxidative stress (MDA, SOD, and GSH), and cytokine analyses (IL-1β, IL-10, TNF-α).

Results: LED therapy significantly enhanced keratinocytes viability compared to sham irradiation, with minimal impact on cell migration. Clinical benefits were prominent on day 10, influencing inflammation progression and resolution on days 3 and 10. Re-epithelization remained unaffected. Reduced MDA and increased GSH levels were observed throughout, while SOD levels varied temporally. Notably, on day 10, LED significantly decreased IL-1β, IL-10, and TNF-α.

Study limitations: Although translational, clinical trial confirmation of observed benefits is warranted.

Conclusions: LED therapy expedites cutaneous healing in the experimental model, primarily modulating inflammation and enhancing antioxidant activity.

Keywords: Cell culture techniques; Cytokines; Dermatology; Low-level light therapy; Models, animal; Oxidative stress.

PubMed Disclaimer

Conflict of interest statement

Conflicts of interest None declared.

Figures

Figure 1
Figure 1
LED effects on human keratinocytes viability and migration in vitro. (A) Percentage of viable cells based on absorbance of SRB assay normalized to Sham 10% group. (B) Main difference in cell viability between experimental groups. (C) Percentage of open wound normalized to baseline (T0) analysis in different experimental times. (D) Main difference in cell migration between experimental groups throw-out the experimental times. Asterisks denote significant results.
Figure 2
Figure 2
Effect of LED therapy on cutaneous healing of Wistar rats. (A) Representative clinical images the healing process of full thickness induced wounds according to experimental groups during the different analysis periods. Note that on day 10 the LED group presented a significantly smaller wound area compared to the Sham group. (B) Percentage of wound closure in different experimental times normalized to baseline wound area (day 0). (B) Main and SD of percentage of wound closure on day 10 in Sham (13.16 ± 1.50) and LED (4.62 ± 2.53) groups. Asterisks denote significant results.
Figure 3
Figure 3
Histopathological evaluation of cutaneous healing. (A) Main (±SD) scores of reepithelization according to experimental groups during the different analysis periods. (B) Main (±SD) scores of inflammations according to experimental groups during the different analysis periods. Asterisks denote significant results. (C) Wound healing site in Sham and LED groups on day 10. Note the abundance of collagen deposition and increase in angiogenesis in LED-treated wounds. (Hematoxylin & Eosin stain, ×100).
Figure 4
Figure 4
Effect of LED therapy on REDOX state and inflammatory cytokines. (A) Main (±SD) levels of (A) MDA, (B) GSH, (C) SOD, (D) IL-1β, (E) IL-10, and (F) TNF-α according to experimental groups during the different analysis periods. Asterisks denote significant results.
See this image and copyright information in PMC

Similar articles

See all similar articles

References

    1. Nussbaum S.R., Carter M.J., Fife C.E., DaVanzo J., Haught R., Nusgart M., et al. An economic evaluation of the impact, cost, and medicare policy implications of chronic nonhealing wounds. Value Health. 2018;21:27–32. - PubMed
    1. Sen C.K. Human wound and its burden: updated 2020 compendium of estimates. Adv Wound Care (New Rochelle) 2021;10:281–292. - PMC - PubMed
    1. Prado T.P., Zanchetta F.C., Barbieri B., Aparecido C., Melo Lima M.H., Araujo E.P. Photobiomodulation with blue light on wound healing: a scoping review. Life (Basel) 2023;13:575. - PMC - PubMed
    1. Wagner V.P., Meurer L., Martins M.A., Danilevicz C.K., Magnusson A.S., Marques M.M., et al. Influence of different energy densities of laser phototherapy on oral wound healing. J Biomed Opt. 2013;18 - PMC - PubMed
    1. Mármora B.C., Brochado F.T., Schmidt T.R., Santos L.G., Araújo A.A., Medeiros C.A.C.X., et al. Defocused high-power diode laser accelerates skin repair in a murine model through REDOX state modulation and reepithelization and collagen deposition stimulation. J Photochem Photobiol B. 2021;225 - PubMed

LinkOut - more resources