Daytime Lipid Metabolism Modulated by CLOCK Gene Is Linked to Retinal Ganglion Cells Damage in Glaucoma

Lipid metabolism is intimately linked to circadian mechanisms and light signaling. Deteriorated photic transduction because of retinal ganglion cell (RGC) loss occurring with glaucoma progression reduces perceived amplitude, causing disruption. To investigate associations RGCs, total cholesterol (TC), its low-density (LDL-C) high-density (HDL-C) fractions, triglycerides (TG) were measured, under a controlled meal regimen, during daytime hours in 114 patients diagnosed primary open-angle (POAG). RGC damage was assessed by high-definition optical coherence tomography (HD-OCT). Analysis eight clock, clock-related, melatonin receptor gene polymorphisms performed on 19 patients. associated changes lipid time-dependent manner. Morning (08:00) values HDL-C (r = 0.613, p < 0.0001) TG 0.568, correlated positively global loss, while LDL-C at 08:00 had weak correlation 0.235; 0.012) but showed strong the evening (20:00) 0.533, 0.0001). The morning–evening gradients (MEGs, 20:00 versus 08:00) TC changed sign from negative positive association exceeding 15% two-eye mean GLV threshold. MEG (LDL-C higher than morning) only POAG CLOCK_3111 TT genotype.