Pulsed Red Photobiomodulation Boosts the Inhibition of Oxytocin-Induced Primary Dysmenorrhea in Mice by Suppressing Oxidative Stress and Inflammation

Increasing evidence has underscored the pivotal role of red photobiomodulation (R-PBM) in analgesic and anti-inflammatory processes; nonetheless, research concerning the effects of pulsed wave on primary dysmenorrhea (PD) remains sparse. This study found that pulsed R-PBM significantly diminished pain responses and levels of PGF_2α/PGE₂, mitigated uterine swelling, augmented antioxidant capacity, and lowered MDA concentrations, which outperformed continuous wave at the same average irradiance. Furthermore, PW treatment substantially reduced ROS levels and enhanced cell viability in PGF_2α induced HUSM cells. NOS levels, especially iNOS, were markedly diminished in the uteri of PD mice, accompanied by significant alterations in inflammation-related genes (Jun, Fos, IL1rn, IL17b) and protein levels, along with pronounced downregulation of calcium ion concentrations after pulsed R-PBM intervention. These findings indicated that pulsed R-PBM may mitigate pain by modulating ROS and NO/NOS, mediated oxidative stress and inflammatory responses. Consequently, pulsed R-PBM emerges as a promising therapeutic strategy for PD.