Abstract
Objective: The objective of this review is to consider the dual effects of microbiome and photobiomodulation (PBM) on human health and to suggest a relationship between these two as a novel mechanism.Background: PBM describes the use of low levels of visible or near-infrared (NIR) light to heal and stimulate tissue, and to relieve pain and inflammation. In recent years, PBM has been applied to the head as an investigative approach to treat diverse brain diseases such as stroke, traumatic brain injury (TBI), Alzheimer's and Parkinson's diseases, and psychiatric disorders. Also, in recent years, increasing attention has been paid to the total microbial population that colonizes the human body, chiefly in the gut and the mouth, called the microbiome. It is known that the composition and health of the gut microbiome affects many diseases related to metabolism, obesity, cardiovascular disorders, autoimmunity, and even brain disorders.Materials and methods: A literature search was conducted for published reports on the effect of light on the microbiome.Results: Recent work by our research group has demonstrated that PBM (red and NIR light) delivered to the abdomen in mice, can alter the gut microbiome in a potentially beneficial way. This has also now been demonstrated in human subjects.Conclusions: In consideration of the known effects of PBM on metabolomics, and the now demonstrated effects of PBM on the microbiome, as well as other effects of light on the microbiome, including modulating circadian rhythms, the present perspective introduces a new term “photobiomics” and looks forward to the application of PBM to influence the microbiome in humans. Some mechanisms by which this phenomenon might occur are considered.
Highlights
Introduction to Light Therapy and theMicrobiomeLight is known to have wide-ranging effects in multiple biological kingdoms,[1] and has been used for many years as a therapeutic agent, in recent years it has fallen from favor
We have shown in a previous study[153] that PBM, delivered as low-level laser, to the abdomen of healthy mice can produce a significant change in the gut microbiome
The combination of the metabolome and the microbiome appears to be able to be changed by light, by PBM
Summary
Light is known to have wide-ranging effects in multiple biological kingdoms,[1] and has been used for many years as a therapeutic agent, in recent years (in the modern era of pharmaceuticals) it has fallen from favor. When CCO absorbs light, the enzyme activity is increased leading to increased electron transport, more oxygen consumption, higher mitochondrial membrane potential, and increased ATP production.[32] Signaling molecules are produced, including a brief burst of reactive oxygen species (ROS), nitric oxide, cyclic AMP, and movements in intracellular calcium These signaling molecules result in activation of a host of transcription factors, and changes in the expression of a multitude of gene products, including structural proteins, enzymes, and mediators of cell division and cell migration.[32] Interestingly, a recent report has thrown into question the central role of CCO in the mechanism of PBM action.[33]. It is possible that circulating immune cells (mast cells, macrophages, etc.), stimulated by PBM,[81,82,83,84] could transduce protective signals from distal tissues to sites of injury such as the brain, heart, or gut
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
