Photobiomodulatory laser acupuncture attenuating the aging-neurodegeneration chain: mechanisms and therapeutic potential against oxidative stress

Abstract

Harman's (1956) theory of oxidative stress posits that reactive oxygen species cause accumulated cellular damage associated with aging, leading to neurodegeneration. The global increase in life expectancy has led to the proposal of various treatments, some with little scientific evidence, including laser acupuncture. The present study constitutes a qualitative research synthesis based on a scoping review of biomedical literature, comprising fifty references with a median publication year of 2019. It was guided by a research question, criteria-based search, and construction of a matrix with three axes: bases of aging and oxidative stress, mitochondrial mechanisms of photobiomodulation and scientific evidence of laser acupuncture. The cellular and molecular mechanisms by which laser acupuncture could modulate mitochondrial oxidative stress were analyzed. The findings suggest that stimulation with low-power laser light activates the cytochrome c oxidase enzyme, increases ATP synthesis, and reduces biomarkers of oxidative damage. It is concluded that laser acupuncture produces neuroprotective effects by interfering in the aging-oxidative stress-neurodegeneration chain. However, standardized clinical studies are required to consolidate this evidence and explore its applicability in population aging.