The mitochondrial theory of aging argues that oxidative stress, caused by
mitochondrial DNA mutations, is associated with decreased
adenosine triphosphate (
ATP) production leading to cellular degeneration. The rate of this degradation is linked to metabolic demand, with the outer retina having the greatest in the body, showing progressive
inflammation, macrophage invasion, and cell loss, resulting in visual decline. Mitochondrial function shifts in vitro after 670-nm light exposure, reducing oxidative stress and increasing
ATP production. In vivo, it ameliorates induced pathology. Here, we ask whether 670 nm light shifts mitochondrial function and reduces age-related
retinal inflammation. Aged mice were exposed to only five 90-second exposures over 35 hours. This significantly increased mitochondrial membrane polarization and significantly reduced macrophage numbers and
tumor necrosis factor (
TNF)-alpha levels, a key proinflammatory
cytokine. Three additional inflammatory markers were assessed;
complement component 3d (C3d), a marker of chronic
inflammation and
calcitonin, and a systemic inflammatory
biomarker were significantly reduced.
Complement component 3b (C3b), a marker of acute
inflammation, was not significantly altered. These results provide a simple route to combating
inflammation in an aging population with declining visual function and may be applicable to clinical conditions where
retinal inflammation is a key feature.