Influence of gut microbiota on eye diseases: an overview

Abstract

The microbiota is a dynamic ecosystem that plays a major role in the host health. Numerous studies have reported that alterations in the intestinal microbiota (dysbiosis) may contribute to the pathogenesis of various common diseases such as diabetes, neuropsychiatric diseases, and cancer. However, emerging findings also suggest the existence of a gut-eye axis, wherein gut dysbiosis may be a crucial factor influencing the onset and progression of multiple ocular diseases, including uveitis, dry eye, macular degeneration, and glaucoma. Currently, supplementation with pre- and probiotics appears is the most feasible and cost-effective approach to restore the gut microbiota to a eubiotic state and prevent eye pathologies. In this review, we discuss the current knowledge on how gut microbiota may be linked to the pathogenesis of common eye diseases, providing therapeutic perspectives for future translational investigations within this promising research field.

Gut Dysbiosis in Ocular Mucous Membrane Pemphigoid

“…There is mounting evidence that the gut microbiome plays a critical role in the development and maturation of the immune system and ocular inflammation ( Kodati and Sen, 2019 ; Mendez et al., 2020 ; Moon et al., 2020 ; Scaglione et al., 2020 ; Napolitano et al., 2021 ). The gut microbiota affects the generation of autoreactive T cells and B cell autoantibody repertoire ( Lee et al., 2011 ; Belkaid and Harrison, 2017 ; Li et al., 2020 ).…”

Do Oral Pathogens Inhabit the Eye and Play a Role in Ocular Diseases?

“…As it is scientifically proven that many systemic diseases manifest in the oral cavity, it is also known that chronic inflammation originating from the oral cavity influence the pathogenesis of diseases at the systemic level [ 61 ]. Several latest studies have strongly suggested the existence of a gut-retinal axis, emphasizing the role of dysbiosis of gut microbiota in the inception and advancement of uveitis [ 62 ], AMD [ 63 ], and glaucoma [ 64 ]. Yet, as early as the 4th century, Hippocrates discussed a case of arthritis healing with the extraction of an infected tooth.…”

Microbiota and Ocular Diseases

“…Oral supplements, antioxidants, minerals, and a diet containing carotenoids have been found in the Age-Related Eye Disease Studies (AREDS and AREDS2) to reduce the risk of AMD progression ( Chew et al., 2015 ). Oral antioxidant supplementation according to AREDS2 is the only intervention that appears to slow the progression of AMD ( Napolitano et al., 2021 ). Recent studies have shown that their efficacy is mediated by intestinal microbiota.…”

“…The selective metabolization of prebiotics in the gut by host microorganisms can purportedly determine the growth and functionality of local bacteria that influence human health ( Napolitano et al., 2021 ). How probiotics modulate the intestinal microbial balance is poorly understood, and the molecular mechanisms have yet to be studied.…”