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.