The study looked at how different kinds of light (UVA, red 650 nm, and infrared 830 nm) affect skin cells that make oil and antimicrobial proteins like LL‑37. It found that these light exposures didn’t boost inflammation, didn’t change the amount of oil the cells produced, and didn’t raise LL‑37 levels. So, the lights seem safe for the skin but don’t dramatically alter sebum or immune‑related peptides.

The effectiveness of ultraviolet (UV) radiation, visible light, or infrared light therapy for the treatment of acne is the subject of ongoing scientific debate. This study was conducted to investigate changes in sebum production and the expression of inflammatory cytokines, matrix metalloproteinases (MMPs), and antimicrobial peptides (AMPs), following exposure of cultured human sebocytes to UVA radiation and light at wavelengths of 650 nm and 830 nm. Reverse transcription polymerase chain reaction assays were performed to measure the gene expression levels of inflammatory cytokines (interleukin [IL]-1β, IL-6, IL-8, and tumor necrosis factor-α), MMPs (MMP-1, MMP-3, and MMP-9), and AMPs (psoriasin, hBD-2, hBD-3, and LL-37) in cultured sebocytes after exposure to UVA radiation (2 J/cm(2), 3 J/cm(2), and 5 J/cm(2)) and light at wavelengths of 650 nm (14 J/cm(2), 29 J/cm(2), and 87 J/cm(2)) and 830 nm (5 J/cm(2), 10 J/cm(2), and 30 J/cm(2)). Expression of inflammatory cytokine proteins and sebum production were measured using enzyme-linked immunoassays and a lipid analysis kit, respectively. Exposure of cultured sebocytes to UVA radiation and light at wavelengths of 650 nm and 830 nm did not show a significant increase in the expression of inflammatory cytokines, MMPs, or AMPs. Sebum production was not significantly decreased after exposure to UVA radiation and light at both wavelengths. We propose that UVA radiation, visible light, and infrared light can be used to target Propionibacterium acnes for the treatment of acne, without an increase in the expression of inflammatory biomarkers and sebum production.