Cytochrome P450 (CYP) gene mutations are a common predisposition associated with glaucoma. Although the molecular mechanisms are largely unknown, omega-3 polyunsaturated fatty acids (ω-3 PUFA) and their CYP-derived bioactive mediators play crucial roles in the ocular system. Here, we elucidated the proteome and cell-signalling alterations attributed to the main human CYP2C gene deficiency using a homologous murine model (Cyp2c44−/−), and unravelled the effects of acute ω-3 PUFA supplementation in two ocular vascular beds comprising the retrobulbar ophthalmic artery (OA) and retina (R). Male Cyp2c44−/− mice (KO) and their floxed littermates (WT) were gavaged daily for 7 days with 0.01 mL/g of ω-3 PUFA composed of menhaden fish oil. Another group in respective strains served as vehicle-treated controls. OA and R were isolated at day 8 post-treatment (n = 9/group) and subjected to mass spectrometry (MS)-based proteomics and in silico bioinformatics analyses. Cyp2c44−/− resulted in significant detrimental proteome changes associated with compromised vascular integrity and degeneration in the OA and R, respectively. However, notable changes in the OA after ω-3 PUFA intake were associated with the maintenance of intercellular junctional and endothelial cell functions, as well as activation of the fatty acid metabolic pathway in the KO mice. Conversely, ω-3 PUFA supplementation profoundly influenced the regulation of a large majority of retinal proteins involved in the preservation of neuronal and phototransduction activities in WT mice, namely synaptophysin, phosducin and guanylate cyclase-1, while significantly abrogating degenerative processes in the KO mice via the regulation of, namely, synaptotagmin-1 and beta-crystallin B2. In gist, this study demonstrated that dietary supplementation with ω-3 PUFA for a short period of seven days regulated specific neuro-vasculoprotective mechanisms to preserve the functionality of the OA and R in the absence of Cyp2c44. The potential adjunct use of ω-3 PUFA for glaucoma therapy needs further investigation.

Purpose: Cytochrome P450 (CYP) gene mutations are associated with the pathogenesis of glaucoma. Although the molecular mechanisms are largely unknown, omega‐3 polyunsaturated fatty acids (ω3) and the CYP‐derived lipid mediators play significant roles in the neurovascular functions of ocular vascular beds. This study explored the proteome changes attributed to inherent lack of the main murine CYP gene (Cyp2c44) and the effects of acute dietary supplementation with ω3 in the retina (R) and ophthalmic artery (OA) in vivo. Methods: Male mice with targeted deletion of the Cyp2c44 gene (KO) and their floxed littermates (WT) were gavaged daily for 7 days with 0.01 ml/g ω3 composed of menhaden fish oil. Another group in respective strains served as vehicle‐treated controls. R and OA were isolated at day 8 post‐treatment (n = 9/group) and subjected to mass spectrometry (MS)‐based proteomics and in‐silico bioinformatics analyses. Results: Acute ω3 administration elicited significant differential expressions of 56 and 18 proteins in the R and OA, respectively. The KO mice exhibited significant retinal degeneration (p = 1.82 E‐2) and compromised microtubule dynamics (p = 9.46 E‐3), while mitochondrial chain deficiency (p = 3.77 E‐8) and inhibition of molecular transport (p = 5.24 E‐5) were implicated in OA. Remarkably, ω3 supplementation in KO mice resulted in significant changes in the R proteins involved in vision functions, and heightened metabolic activity via glycolysis and AMPK signalling (CRYBB2, ALDOC, ENO2). Noteworthy, ω‐3 had a profound influence on the regulation of OA proteins involved in the inhibition of necrosis, activation of molecular transport and intercellular junctional organization (HSPA8, HK1, YWHAB). Conclusions: In gist, short‐term dietary supplementation with ω3 confers physiologically relevant beneficial effects on the ocular vascular beds via specific neuro‐vasculoprotective signalling mechanisms in the absence of Cyp2c44. The potential adjunct use of ω3 for glaucoma therapy needs further investigation.