Red and near infra-red signaling: Hypothesis and perspectives

The review covers some of the proposed cellular photoreceptors responsible for the effect of red and near infra-red (NIR) light on mammalian cells, including cytochrome-c-oxidase, photoactive porphyrins, flavoproteins, and molecular oxygen. We do not discuss the clinical studies but consider animal models, especially fibroblasts. Several key hypotheses such as mitochondria signaling and free-radical conception of the effects of red light and NIR light based on the changes in redox properties of photoreceptor molecules as well as membrane conception are examined. Special attention is paid to common mechanisms of light signaling in mammalian and plant organisms.

► Red and near infra-red signaling are reviewed. ► Light signaling in animal and plant cells are analyzed. ► Hypothesis and perspectives are discussed.