Effects of Sodium Hyaluronate Eye Drops With or Without Preservatives on Ocular Surface Bacterial Microbiota

Abstract

PurposeThis study aimed to determine the composition and diversity of bacterial communities on the ocular surface before and after the intervention with sodium hyaluronate eye drops (with or without preservatives) using 16S rRNA gene amplicon sequencing.MethodsSixteen healthy adults were randomly divided into two groups and treated with sodium hyaluronate eye drops with or without preservatives for 2 weeks. The individuals used the same artificial tears in both eyes. The microbial samples from the conjunctival sac of each participant were collected at baseline and 2 weeks after intervention. The diversity and taxonomic differences among different groups before and after intervention were compared by sequencing the V3–V4 region of the 16S rRNA gene.ResultsThe similarity in the binocular microbial community was high in 1 of the 16 volunteers (Bray-Curtis dissimilarity score < 0.3). At the genus level, 11 bacteria were detected in all samples with an average relative abundance of more than 1%. The bacterial community changed significantly after the use of sodium hyaluronate eye drops (with or without preservatives), whether within individuals or between individuals in different groups (P < 0.05, PERMANOVA). Different dosage forms of sodium hyaluronate eye drops significantly decreased the relative abundance of Flavobacterium caeni and Deinococcus antarcticus, respectively (P < 0.05).ConclusionsHealthy people had a rich diversity of the bacterial microbiota on the ocular surface, but the bacterial communities between the eyes were not completely similar. Irrespective of containing benzalkonium chloride (BAC), sodium hyaluronate eye drops can change the bacterial community on the ocular surface.

Effects of Carboxymethylcellulose Artificial Tears on Ocular Surface Microbiome Diversity and Composition, A Randomized Controlled Trial

“…4 a, 4 b) indicate that neither CMC-AT nor PEG-AT interventions changed the alpha diversity of the OSMs. A randomized controlled study by Zhong et al 32 on 16 healthy adults also found no significant differences in the OSM alpha diversity after two weeks of sodium hyaluronate ATs with or without benzalkonium chloride preservative. Another randomized controlled study on 36 patients by Willis et al 22 found small increases in alpha diversity after one month of saline solution eye washes in DES patients.…”

“… 21 , 22 , 27 , 41 One study found changes in the OSM after topical application of sodium hyaluronate, but only compared preserved and non-preserved solutions. 32 Another study found no changes of the eyelid margin microbiome based on eyedrop preservatives. 42 As a result, there are currently few reasons to choose one AT over another comparable formulation.…”

“… 28 Studies on the eyelid microbiome and OSM have shown that prostaglandin analogues increase beta diversity, topical anesthetics have been shown to decrease Cutibacterium species, and sodium hyaluronate have been shown to decrease abundance of specific bacterial species such as Flavobacterium caeni and Deinococcus antarcticus . 29 – 32 It therefore stands to reason that CMC-ATs may also have measurable effects on the OSM.…”

Exploring the Healthy Eye Microbiota Niche in a Multicenter Study

“…The eSwab was applied on the inferior surface of the eye and moved 2 times “limbus to fornix to limbus”. No fluorescein and anesthetics were used to avoid influences on the eye microbiota [ 27 , 47 ].…”

Role of the ocular surface microbiome in allergic eye diseases

“…As benzalkonium chloride (BAC) is a common preservative in eye drops used for its antimicrobial effects, it has the potential to alter the bacterial composition of the OSM [51]. However, Zhong et al [52] reported that even a 2-week course of topical artificial tear drops with or without preservatives is enough to change the microbial profile of healthy individuals, suggesting that multiple benign agents can hypothetically disturb the delicate composition of the OSM. Given the presumed disruption of ocular surface homeostasis and defense mechanisms with long-term immunosuppressant eye drops (i.e.…”