High-Dose Sucralose Is Associated With Lacrimal Circadian Remodeling, Reduced Immunometabolic Signatures, and Reduced Tear Secretion.

PURPOSE: To determine whether high-dose sucralose (SUC) exposure alters circadian organization of the mouse extraorbital lacrimal gland, immunometabolic pathways, and tear film function using multi-omics and functional assays.

METHODS

Male C57BL/6J mice received SUC (0.72 mg/mL in drinking water) or water under a 12:12 hour light-dark cycle for 30 days. Extraorbital lacrimal glands were collected every 3 hours across 24 hours (n = 3/time point/group) for RNA sequencing and 4D-data-independent acquisition proteomics. Rhythms were identified with JTK_CYCLE, differential expression with DESeq2/MSstats followed by Kyoto Encyclopedia of Genes and Genomes pathway analysis. Oil Red O and CD4/CD8 immunohistochemistry assessed lipid and immune signatures. Tear secretion, tear film breakup time, and corneal fluorescein staining were measured at ZT0, ZT6, ZT12, and ZT18.

RESULTS

SUC increased rhythmic transcripts (3074 to 4600) and proteins (378 to 984), redistributing acrophases (transcript peaks shifted toward ZT3-ZT6; protein peaks toward ZT21-ZT24), indicating clock phase remodeling. Both omics layers converged at the pathway level, showing downshifts in metabolic and immune programs, including complement- and T-cell-related signatures. SUC elevated water intake and body weight without altering glucose tolerance. Functionally, SUC-treated mice showed reduced stimulated tear secretion, whereas tear film breakup time and corneal fluorescein staining did not differ significantly.

CONCLUSIONS

Under this high-exposure paradigm, SUC was associated with lacrimal circadian remodeling, reduced metabolic and immune pathway signatures, and lower stimulated tear secretion, identifying candidate pathways for mechanistic testing without establishing direct causality.