The Gut–Eye Axis: Correlation Between the Gut Microbiota and Autoimmune Dry Eye in Individuals With Sjögren Syndrome

Abstract

The impact of gut microbiota on human health, autoimmunity, and disease occurrence has long been recognized since the advancement of metagenomic sequencing technology has enabled a new level of perspective on the human microbiome. Emerging findings also suggest the existence of a gut-eye axis, wherein gut dysbiosis may be a crucial factor affecting the onset and progression of multiple ocular diseases. Sjögren syndrome (SS) is a chronic autoimmune disease mainly affecting the exocrine glands, primarily the lacrimal gland in the eye, resulting in severe dry eye. Although there are currently various treatments for environmental dry eye, the efficacy for SS-related autoimmune dry eye is limited, and new and more effective therapies still need to be explored. The latest studies have demonstrated that the gut microbiota plays a key role in the pathogenesis of autoimmune dry eye. This review describes the effect of gut microbiota on the ocular surface of autoimmune dry eye; introduces the presumable pathways forming the "gut dysbiosis-ocular surface-lacrimal gland axis"; discusses the advantages of restoring intestinal microecology to treat dry eye by fecal microbiota transplantation or probiotics, which are expected to provide perspectives into the correlation between the gut microbiome and dry eye; enhance our understanding of the pathogenesis in autoimmune dry eye; and be useful in the development of future interventions of dry eye by regulating the gut microbiota.

Ocular surface microbiota in patients with varying degrees of dry eye severity

“…Some studies demonstrate that the effectiveness of supplementation with prebiotics or probiotics in reducing DE is associated with improved tear film function and restored OS microbiological activity in patients with DE [38][39] . This may also be an option for future DE treatment, as there have been studies confirming the existence of a gut-eye axis [40][41] . The OS microbiome is an extremely complicated issue that requires extensive research.…”

Visual analysis of autoimmune dry eye studies based on bibliometrics

“…Recently, the study of intestinal flora is in the hot spot. some of them [27] have analyzed the mechanism of xerophthalmia based on intestinal-eye axis, speculated the possible pathway of intestinal microflora imbalance-ocular surface-lacrimal gland axis formation, and discussed the advantages of fecal microflora transplantation or probiotic restoration of intestinal microecology in the treatment of xerophthalmia. After that, the study on the relationship between intestinal flora and xerophthalmia will also become a new research direction.…”

Recommendations for nutritional supplements for dry eye disease: current advances

“…Patients with autoimmune DED often experience damage to ocular surface tissues such as the cornea, conjunctival goblet cells, and lacrimal glands. This damage is frequently associated with alterations in gut microbial diversity and abundance ( Bai et al, 2023 ), which can trigger systemic inflammation and contribute to a range of ocular disorders, including age-related macular degeneration, uveitis, diabetic retinopathy, and glaucoma ( Bai et al, 2023 ; Campagnoli et al, 2023 ).…”