To characterize the composition and functional features of the aqueous humor microbiome in common ocular diseases, including myopia, cataract, primary open angle glaucoma (POAG), and Posner-Schlossman syndrome (PSS).

We performed metagenomic sequencing on 176 aqueous humor samples from patients with cataract (n=37), POAG (n=66), PSS (n=35), and myopia patients (n=38, as controls). Taxonomic profiling, functional annotation, and diversity analyses were conducted to characterize microbial communities, with adjustments for age and gender where appropriate. Associations between microbial features and clinical parameters were evaluated using correlation analyses.

We identified 6635 bacterial, 141 archaeal, 96 eukaryotic, and 108 viral operational taxonomic units (OTUs) in the aqueous humor. The microbiome was dominated by Actinomycetota and Pseudomonadota at the phylum level. Compared to myopia controls, POAG and PSS patients showed significantly reduced alpha diversity after age adjustment (P<0.05), whereas cataract patients showed no significant difference. Additionally, we identified disease-specific microbial signatures including enrichment of Cytomegalovirus (CMV) in PSS. Functional analysis revealed enrichment of distinct metabolic pathways. Finally, correlations were observed between microbiota/pathway abundance and clinical phenotype, though none remained significant after multiple testing correction.

This study provides a preliminary characterization of the aqueous humor microbiome in patients with POAG, PSS, cataract, and myopia controls. The identified microbial signatures and functional pathways offer new insights into potential microbiome-mediated mechanisms in ocular pathophysiology and may inform future diagnostic and therapeutic strategies.

To investigate the role of adipokines in primary open angle glaucoma (POAG) by comparing the levels of these molecules in the aqueous humor among POAG patients and cataract patients with or without metabolic disorders.

In this cross-sectional study, aqueous humor samples of 22 eyes of POAG patients (POAG group), 24 eyes of cataract patients without metabolic disorders (cataract group), and 24 eyes of cataract patients with metabolic disorders (cataract+metabolic disorders group) were assessed for 15 adipokines by Luminex bead-based multiplex array. The correlation between aqueous humor adipokines and clinical indicators of POAG was analyzed and compared across the groups.

The analysis revealed that the levels of adiponectin, leptin, adipsin, retinol-binding protein 4 (RBP4), angiopoietin-2, angiopoietin-like protein 4 (ANGPTL4), chemokine (C-C motif) ligand 2 (CCL2), interleukin-8 (IL-8), and interleukin-18 (IL-18) in the aqueous humor of the POAG group were significantly higher than those in the cataract group. Additionally, the level of angiopoietin-2 in the POAG group was higher than in the cataract+metabolic disorders group. However, no significant correlation was found between the levels of adipokines in the POAG group and intraocular pressure (IOP), severity of POAG, or the use of glaucoma medications.

This study demonstrates significant differences in aqueous humor adipokine levels between POAG and cataract patients. The findings suggest that the levels of aqueous humor adipokines may reflect the inflammatory states in POAG and systemic metabolic abnormalities.