Non-thermal Therapeutic Applications of Light

Abstract

Phototherapy or light-based treatment is emerging as a very promising biophysical, non-invasive or minimal invasive and non-traumatic healing modality. It includes photobiomodulation (PBM) therapy and photodynamic therapy (PDT). PBM involves irradiation of injured tissue with photons mostly in the red and near-infrared region at relatively low-intensity (non-thermal). This light absorption causes photophysical and photochemical reactions, which in turn sets in various biological events like stimulation of cell growth, attenuation of inflammation, pain and recovery from damage. PDT makes use of photoactivated dye known as photosensitizer to kill multi-drug resistant microorganisms and cancer cells. Apart from investigations on their therapeutic efficacy, a lot of work is being carried out to generate a better understanding of the mechanisms of action of light-based therapy at the cellular and molecular levels, and downstream effector molecules. The present article provides a brief overview of the activity in this field with emphasis on the work carried out in the country.