Neuro-lymphaphotonics opens new horizons of the future technologies for the therapy of brain diseases

Pharmacological treatment of brain diseases is hampered by the blood-brain barrier that prevents the vast majority of drugs from entering the brain. For this reason, the pharmaceutical industry is reluctant to invest in the development of new neurotropic drugs. Even if effective pharmacological strategies for the treatment of brain diseases will be found, it will take 10-15 years between the emergence of an idea and the introduction of a drug to the market. This creates priority for the development of neuro-lymphaphotonics based on the development of promising non-pharmacological strategies for managing functions of the meningeal lymphatic vessels (MLVs). MLVs play a crucial role in the removal of toxins and metabolites from brain as well as in regulation of brain homeostasis and its immunity. Since MLVs are located on the brain surface, light penetrating the skull easily reaches MLVs and affects their functions. Therefore, MLVs are an ideal target for photobiomodulation (PBM). The pioneering studies have shown that PBM of MLVs is a promising strategy for the treatment of a wide range of neuropathology, including Alzheimer's or age-related brain diseases, brain tumor, intracranial hemorrhage, brain damages caused by diabetes. It has recently been discovered that sleep enhances the therapeutic effects of PBM and is a "therapeutic window" in overcoming the limitations of PBM in the elderly. Considering that the PBM technologies are non-invasive and safe with commercially viable possibilities (portability and low cost), neuro-lymphaphotonics open up promising prospects for the development of future technologies for the effective therapy of brain diseases.