Class 3B LASER PBM Produces a Joule-Response Dependent Analgesic Effect in Complete Freund Adjuvant-Induced Inflammation in a Mouse Model
Francisco José Cidral-Filho, Neito Antonio Bonotto, Bruna Hoffman de Oliveira, Aline Raulino Dutra, Juliana Nazário, Daniel Fernandes Martins
Experimental Neuroscience Laboratory (LaNEx), Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, SC, Brazil.
Abstract
Objective: This study assessed the pain-relieving (antihyperalgesic) and anti-swelling (antiedematogenic) effects of Class 3B laser photobiomodulation (PBM) in mice with induced peripheral inflammation.
Methods: Inflammation was induced in male Swiss mice via intraplantar (i.pl.) injection of Complete Freund’s Adjuvant (CFA). Mice were treated with various energy densities of PBM (2–20 J/cm²) over five days, using a high-power Class 3B laser system (Avant Wellness LZ30 Pro Z, 1,400 mW at 808 nm and up to 1,000 mW at 637 nm). Mechanical hyperalgesia (pain response) and paw edema (swelling) were measured. The mechanical hyperalgesia was evaluated at 0.5, 1, 2, 3, and 4 hours after treatments. Edema was evaluated 4 hours after treatment on days 1, 3, and 5 after CFA injection.
Results: CFA injection caused persistent pain in the mice’s paws. PBM at energy densities of 4, 8, and 12 J/cm² significantly reduced pain on day 1, with the 8 J/cm² dose providing the longest-lasting relief. On day 5, PBM at 4, 8, and 20 J/cm² effectively reduced pain, with 8 J/cm² again showing the best results. Repeated daily treatment with 4 and 8 J/cm² significantly inhibited pain over five days. However, PBM did not significantly reduce paw swelling.
Conclusion: Class 3B LASER PBM effectively reduces pain in a dose-dependent manner but does not significantly impact inflammation-related swelling. The results reinforce the therapeutic benefits of high-power Class 3B laser applications, demonstrating that increased power output, as seen with the LZ30 Pro Z, may enhance clinical outcomes in pain management for inflammatory conditions.
Keywords: Future Medicine, Integrative Therapy, Light Therapy, Pain, Photobiomodulation.
Presented at the IASP 2024 WORLD CONGRESS ON PAIN, Amsterdam, Netherlands (5-9 August).
Abstract available online
Laser details: Avant Wellness LZ30 Pro Z
