Microbiota and age-related macular degeneration: where are we today?

Abstract

Age-related macular degeneration (AMD) is a complex degenerative multifactorial retinal disease, representing a leading cause of legal blindness among elderly individuals. It is well known that age, family history, smoking, nutrition, and inflammation contribute to the development of AMD. Recent studies support the existence of a gut-retina axis involved in the pathogenesis of several ocular diseases, including AMD. High-fat and high simple sugar diets determine a derangement of the gut microbiota, with an increase of gut permeability and systemic low-grade inflammation. Leaky gut is correlated with higher levels of circulating microbial-associated pattern molecules, which trigger the systemic release of potent proinflammatory mediators and stimulate the specific immune cells of the retina, contributing to retinal damage. All these findings suggest that microbiota is closely related to AMD and that it may be targeted in order to influence AMD pathogenesis and/or its clinical course.