Photobiomodulation therapy for osteoarthritis: Mechanisms of action

Figure 1 Photobiomodulation at near infrared light stimulates a subset of biochemical reactions in the mitochondrion in order to trigger transcription of genes associated with positive biological effects. ROS: Reactive Oxygen Species; ATP: Adenosine Triphosphate; PKD: Protein Kinase D; cAMP: Cyclic Adenosine Monophosphate; IkB: IkappaB kinase; NF-kB: Nuclear factor kappa-light-chain-enhancer of activated B cells; Jun/Fos: Proto-oncogenes; AP-1: Activator protein 1.

Figure 2 In vitro application of wavelengths between 600 – 980 nm stimulates differentiation, proliferation and the secretion of specific cytokines and growth factors for further modulatory roles.

Figure 3  Photobiomodulation at a wavelength of 940 nm blocks the transmission of pain through sensory neuron fibers, thus promoting analgesic effects.

Figure 4  The application of photobiomodulation between 600 – 980 nm can attenuate inflammation by decreasing the production of pro-inflammatory agents and regulating the activation of immune cells.