Unraveling Laser-Induced peripheral Pain: Proteomic profiling and electrophysiological Dynamics in mice

With the rapid development of their technology, lasers are now widely used in science and industry over a range of fields. Unfortunately, accidents involving lasers also occur, in which there is a risk of skin damage and pain. At present, there are few studies on laser-induced pain, and the mechanism of peripheral pain following irradiation remains unclear. In this study, we aim to explore the pain-causing effects of laser irradiation on the skin. The plantar skin of mice was irradiated with an 808 nm diode laser. Different laser power levels and durations were used to determine optimal parameters for a laser-induced pain model. The mechanical withdrawal threshold detected by von Frey, skin cell damage via hematoxylin and eosin (H&E) staining, electrophysiological properties of dorsal root ganglia (DRG) and applied proteomics were employed to explore mechanisms underlying laser-induced skin pain. Our findings indicate that after being irradiated with 808 nm light from a diode laser at 2.5 W for 25 s, mice produce relatively stable pain responses, with peak pain sensitivity reached on the 14th day. The results of H&E staining of the plantar skin tissue after irradiation showed inflammation. Compared with the control group, the excitability of small DRG neurons in the laser-treated group was significantly elevated. Proteomic profiling revealed differential expression of S100A8/A9, TRPV1, and IL-17A, implicating these proteins as potential mediators of laser-induced nociception at the cellular level. This laser-induced pain model provides a robust platform for developing protective interventions.