New research on mice conducted at the Montreal Neurological Institute and Hospital of McGill University and the McGill University Health Centre claims to confirm the demonstrated potential of light as a therapeutic option for pain that is both noninvasive and highly focused. The mice were bred with a genetic trait in peripheral neurons called NAV 1.8+ nociceptors, causing them to express proteins called opsins that react to light. When the neurons are exposed to yellow light, the effect of opsin expression is to decrease the mouse’s sensitivity to touch and heat. The process is known as optogenetics, a growing field of research with a wide range of potential applications.
The research team found that both the location of neuron activity and the duration of pain-signally effect could be easily controlled by the amount of time that light was applied, demonstrating the precision of the technique. Thus, pain therapy based on optogenetics could have the advantage of affording “on-demand” analgesia via light directed to specific body areas. By contrast, opioid therapy is often systemically applied, and while the duration of effect can be estimated, it is not with the same precision as with light. Senior author Philippe Séguéla, PhD, posited that one approach to making human neurons photosensitive would be through a harmless virus that temporarily delivers opsins to certain neurons without associated side effects.
Read more about the optogenetic therapy here.