Effects of amber LED on inflammatory and regulatory monocytes and lymphocytes

• Published in: Journal of photochemistry and photobiology. B, Biology Biology, 2024-02, Vol.251, p.112848-112848, Article 112848
• Main Authors: de Brito Sousa, Kaline, dos Santos Malavazzi, Tainá Caroline, Rodrigues, Maria Fernanda Setúbal Destro, Silva, Tamiris, Andreo, Lucas, Deana, Alessandro Melo, Nunes, Fabio Daumas, Bussadori, Sandra Kalil, Mesquita-Ferrari, Raquel Agnelli, Fernandes, Kristianne Porta Santos
• Format: Article
• Language: English
• Subjects: Amber; Cells, Cultured; Cytokines - metabolism; Humans; Interleukin-10 - metabolism; Interleukin-17 - metabolism; Interleukin-4 - metabolism; Interleukin-6 - metabolism; LED; Leukocytes; Lipopolysaccharides - pharmacology; Lymphocytes - metabolism; Monocytes - metabolism; Optical absorbance; Photobiomodulation; Tumor Necrosis Factor-alpha - metabolism
• ISSN: 1011-1344; 1873-2682
• DOI: 10.1016/j.jphotobiol.2024.112848

The primary objective of the present study was to assess the impact of amber LED photobiomodulation (PBM) on human monocytes and lymphocytes that were polarized into proinflammatory and regulatory/reparative phenotypes. Human leukocytes were polarized with LPS or LPS + IL-4 for 2 h and irradiated after 2 and 6 h with amber LED (590 nm). Cell absorbance spectrum and gene and protein expression of IL-1β, IL-6, IL-10, IL-17, TNF-α and IFNγ determined after 24 h. The results showed that irradiation did not significantly alter absorbance of non-polarized monocytes, whereas irradiated polarized monocytes presented reduction in absorbance in 625-850 nm region. Irradiated monocytes polarized with LPS + IL-4 presented reduction in absorbance in 600-725 nm region compared to non-irradiated group. Irradiated non-polarized lymphocytes presented absorbance peaks between 650 and 820 nm not seen in non-irradiated group. No difference was found in absorbance pattern of polarized lymphocytes after irradiation. Irradiation led to reduction in protein synthesis of IL-6 and TNFα in monocytes polarized to proinflammatory phenotype and increase in production of IL-17 in lymphocytes. Irradiation reduced production of IL-10 in monocytes and lymphocytes polarized to immunoregulatory phenotype. In conclusion, amber LED modulates light absorbance and expression of important cytokines in inflammatory/repair processes in monocytes and lymphocytes. [Display omitted] •Proinflammatory or regulatory leukocytes modulate the inflammatory process and coordinate regeneration.•Amber light has been described for the control of inflammation and tissue repair.•Monocytes and lymphocytes polarized showed optical absorbance in the amber wavelength.•Monocytes treated with amber LED exhibited less absorbance compared to M1 monocytes.•LED decreases IL-6 and TNFα protein in M1 monocytes and increases IL-17 in L1 lymphocytes.