Interaction mechanism between gut-retina axis and eye diseases

Gut microbiome is an important part of maintaining human homeostasis.In recent years, with the rapid development of sequencing technologies such as 16S rRNA and metagenome, people have a deeper and more comprehensive understanding about microorganisms.Studies in animals and humans have confirmed that the gut microbiome is not only involved in the pathological process of systemic diseases such as immune, metabolic and neurological disorders, but is also closely related to eye diseases.Factors such as host high blood glucose, immune disorders, aging, high intraocular pressure can cause gut microbiota dysbiosis and increase gut-blood barrier permeability.Lipopolysaccharide, peptidoglycan and other pathogen-associated molecular patterns enter the systemic circulation through the damaged gut barrier and eventually reach the retina and uveitis where they participate the immune and inflammatory response process.In addition, gut-derived host immune cells or injury-related molecular patterns may exacerbate the ocular inflammatory cascade.At the same time, metabolites of microbiota, including those induced by diet and environment factors, such as bilirubin, bile acids and short-chain fatty acids, are involved in the progression of retinal diseases via regulating immune T cell balance, miRNA expression and retinal cell inflammatory activation.This article aims to review the domestic and foreign studies on gut microbiome in diabetic retinopathy, uveitis, age-related macular degeneration and glaucoma in recent years, and discuss the possible mechanisms of gut microbiome in eye diseases via the gut-retina axis in order to provide some new ideas for further study and treatment of eye diseases.

KEYWORDS：

Gut microbiome;Gut-retina axis;Diabetic retinopathy;Uveitis;Age-related macular degeneration;Glaucoma